Journal articles on the topic 'Vetrazin Controlled release Mathematical models'
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Yahya, Ibtihag, Razan Atif, Lina Ahmed, Tahleel Salah Eldeen, Akram Omara, and Megdi Eltayeb. "Polymeric Nanoparticles as Drug Delivery Systems for Controlled Release." Advanced Science, Engineering and Medicine 12, no. 2 (February 1, 2020): 263–70. http://dx.doi.org/10.1166/asem.2020.2495.
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This study focuses on providing a comparative mathematical analysis of drug release from polymeric nanoparticle with different structures to allow in silico prediction of the appropriate and optimal model that applies to the whole drug release and not limited to a part of the process. The drug release data from nanoparticles have been applied using MATLAB software to apply mathematical models such as Zero-order, First-order, Higuchi, Hixson–Crowell, Korsmeyer-Peppas models besides a proposed model called Tanh function. This study results highlight the usefulness of mathematical models, key findings emerge that the Tanh model and First-order model gave the best fits of the parameters data as both model's plots showed high linear correlation (R2 = 0.9781, 0.9448) respectively. Finally, this study concludes that both proposed Tanh function and First-order model shows better performance, giving good results and can be successfully used to characterize drug and applied for prolonged drugs release.
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Manga, Ramya D., and Prateek K. Jha. "Mathematical Models for Controlled Drug Release Through pH-Responsive Polymeric Hydrogels." Journal of Pharmaceutical Sciences 106, no. 2 (February 2017): 629–38. http://dx.doi.org/10.1016/j.xphs.2016.10.019.
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Paolino, Donatella, Andra Tudose, Christian Celia, Luisa Di Marzio, Felisa Cilurzo, and Constantin Mircioiu. "Mathematical Models as Tools to Predict the Release Kinetic of Fluorescein from Lyotropic Colloidal Liquid Crystals." Materials 12, no. 5 (February 26, 2019): 693. http://dx.doi.org/10.3390/ma12050693.
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In this study, we investigated the release kinetic of fluorescein from colloidal liquid crystals made from monoglyceride and different non-ionic surfactants. The crystals were physicochemically characterized and the release experiments were carried out under the sink conditions, while mathematical models were described as extrapolations from solutions of the diffusion equation, in different initial and boundary conditions imposed by pharmaceutical formulations. The diffusion equation was solved using Laplace and Fourier transformed functions for release kinetics from infinite reservoirs in a semi-infinite medium. Solutions represents a general square root law and can be applied for the release kinetic of fluorescein from lyotropic colloidal liquid crystals. Akaike, Schwartz, and Imbimbo criteria were used to establish the appropriate mathematical model and the hierarchy of the performances of different models applied to the release experiments. The Fisher statistic test was applied to obtain the significance of differences among mathematical models. Differences of mathematical criteria demonstrated that small or no significant statistic differences were carried out between the various applied models and colloidal formulations. Phenomenological models were preferred over the empirical and semi-empirical ones. The general square root model shows that the diffusion-controlled release of fluorescein is the mathematical models extrapolated for lyotropic colloidal liquid crystals.
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Mircioiu, Constantin, Victor Voicu, Valentina Anuta, Andra Tudose, Christian Celia, Donatella Paolino, Massimo Fresta, Roxana Sandulovici, and Ion Mircioiu. "Mathematical Modeling of Release Kinetics from Supramolecular Drug Delivery Systems." Pharmaceutics 11, no. 3 (March 21, 2019): 140. http://dx.doi.org/10.3390/pharmaceutics11030140.
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Embedding of active substances in supramolecular systems has as the main goal to ensure the controlled release of the active ingredients. Whatever the final architecture or entrapment mechanism, modeling of release is challenging due to the moving boundary conditions and complex initial conditions. Despite huge diversity of formulations, diffusion phenomena are involved in practically all release processes. The approach in this paper starts, therefore, from mathematical methods for solving the diffusion equation in initial and boundary conditions, which are further connected with phenomenological conditions, simplified and idealized in order to lead to problems which can be analytically solved. Consequently, the release models are classified starting from the geometry of diffusion domain, initial conditions, and conditions on frontiers. Taking into account that practically all solutions of the models use the separation of variables method and integral transformation method, two specific applications of these methods are included. This paper suggests that “good modeling practice” of release kinetics consists essentially of identifying the most appropriate mathematical conditions corresponding to implied physicochemical phenomena. However, in most of the cases, models can be written but analytical solutions for these models cannot be obtained. Consequently, empiric models remain the first choice, and they receive an important place in the review.
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Haidar, Ziyad S. "Mathematical Modeling for Pharmacokinetic Predictions from Controlled Drug Release Nano Systems: A Comparative Parametric Study." Biomedical and Pharmacology Journal 11, no. 4 (December 25, 2018): 1801–6. http://dx.doi.org/10.13005/bpj/1552.
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In the present work, several mathematical models well-known in the literature for simulating drug release kinetics are compared using available experimental data sets obtained in real systems with different drugs and nano-sized carriers. Herein, the χ2 minimization method, is employed concluding that the Korsmeyer-Peppas model provides the best-fit in all cases. Hence, (i) better understanding of the exact mass transport mechanism(s) involved in drug(s) release, and (ii) quantitative prediction of the drug release kinetics, can be computed.
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Abed, Ziaeddin, Samideh Khoei, Behafarid Ghalandari, Jaber Beik, Ali Shakeri-Zadeh, Habib Ghaznavi, and Mohammad-Bagher Shiran. "The Measurement and Mathematical Analysis of 5-Fu Release from Magnetic Polymeric Nanocapsules, following the Application of Ultrasound." Anti-Cancer Agents in Medicinal Chemistry 18, no. 3 (June 4, 2018): 438–49. http://dx.doi.org/10.2174/1871520617666170921124951.
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Objective: To study the effects of ultrasound irradiation on the release profile of 5-fluorouracil (5-Fu) loaded magnetic poly lactic co-glycolic acid (PLGA) nanocapsules. Also, the controlled drug-release behaviour of the nanocapsules was mathematically investigated. Methods: The nanocapsules were synthesized, dispersed in phosphate buffered saline (PBS), transferred to a dialysis bag, and finally, irradiated by various ultrasound parameters (1 or 3MHz; 0.3-1W/cm2; 5-10 minutes). The release profile of the irradiated nanocapsules was recorded for 14 days. To find the in vitro drug release mechanism in the absence and presence of various intensities of ultrasound, the obtained data were fitted in various kinetic models for drug release. Results: The results demonstrated that the ultrasound speeded up the rate of drug release from the nanocapsules. The mathematical analysis illustrated that when the ultrasound intensity is increased, the probability of controlled release behaviour of the nanocapsules is raised. We found that drug release from the irradiated nanocapsules follows an erosion-controlled mechanism with the decrease in the velocity of diffusion. Conclusion: In conclusion, to attain a controlled drug-delivery strategy in the area of cancer therapy, the drug release profile of the nano-carriers may be well-controlled by ultrasound.
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Sempeho, Siafu Ibahati, Hee Taik Kim, Egid Mubofu, and Askwar Hilonga. "Meticulous Overview on the Controlled Release Fertilizers." Advances in Chemistry 2014 (August 28, 2014): 1–16. http://dx.doi.org/10.1155/2014/363071.
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Owing to the high demand for fertilizer formulations that will exhaust the possibilities of nutrient use efficiency (NUE), regulate fertilizer consumption, and lessen agrophysicochemical properties and environmental adverse effects instigated by conventional nutrient supply to crops, this review recapitulates controlled release fertilizers (CRFs) as a cutting-edge and safe way to supply crops’ nutrients over the conventional ways. Essentially, CRFs entail fertilizer particles intercalated within excipients aiming at reducing the frequency of fertilizer application thereby abating potential adverse effects linked with conventional fertilizer use. Application of nanotechnology and materials engineering in agriculture particularly in the design of CRFs, the distinctions and classification of CRFs, and the economical, agronomical, and environmental aspects of CRFs has been revised putting into account the development and synthesis of CRFs, laboratory CRFs syntheses and testing, and both linear and sigmoid release features of CRF formulations. Methodical account on the mechanism of nutrient release centring on the empirical and mechanistic approaches of predicting nutrient release is given in view of selected mathematical models. Compositions and laboratory preparations of CRFs basing on in situ and graft polymerization are provided alongside the physical methods used in CRFs encapsulation, with an emphasis on the natural polymers, modified clays, and superabsorbent nanocomposite excipients.
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Panotopoulos, Grigorios P., and Ziyad S. Haidar. "Mathematical Modeling for Pharmaco-Kinetic and -Dynamic Predictions from Controlled Drug Release NanoSystems: A Comparative Parametric Study." Scientifica 2019 (January 6, 2019): 1–5. http://dx.doi.org/10.1155/2019/9153876.
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Predicting pharmacokinetics, based on the theory of dynamic systems, for an administered drug (whether intravenously, orally, intramuscularly, etc.), is an industrial and clinical challenge. Often, mathematical modeling of pharmacokinetics is preformed using only a measured concentration time profile of a drug administered in plasma and/or in blood. Yet, in dynamic systems, mathematical modeling (linear) uses both a mathematically described drug administration and a mathematically described body response to the administered drug. In the present work, we compare several mathematical models well known in the literature for simulating controlled drug release kinetics using available experimental data sets obtained in real systems with different drugs and nanosized carriers. We employed the χ2 minimization method and concluded that the Korsmeyer–Peppas model (or power-law model) provides the best fit, in all cases (the minimum value of χ2 per degree of freedom; χmin2/d.o.f. = 1.4183, with 2 free parameters or m = 2). Hence, (i) better understanding of the exact mass transport mechanisms involved in drugs release and (ii) quantitative prediction of drugs release can be computed and simulated. We anticipate that this work will help devise optimal pharmacokinetic and dynamic release systems, with measured variable properties, at nanoscale, characterized to target specific diseases and conditions.
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Ghosal, Kajal, and Sarbani Dey Ray. "Alginate/hydrophobic HPMC (60M) particulate systems: new matrix for site-specific and controlled drug delivery." Brazilian Journal of Pharmaceutical Sciences 47, no. 4 (December 2011): 833–44. http://dx.doi.org/10.1590/s1984-82502011000400021.
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This study aimed to obtain site-specific and controlled drug release particulate systems. Some particulates were prepared using different concentrations of sodium alginate (Na-Alg) alone and others were formulated using different proportions of Na-Alg with hydroxypropyl methylcellulose (HPMC) stearoxy ether (60M viscosity grade), a hydrophobic form of conventional HPMC, using diclofenac potassium (DP) by ion-exchange methods. Beads were characterized by encapsulation efficiency, release profile, swelling, and erosion rate. The suitability of common empirical (zero-order, first-order and Higuchi) and semi-empirical (Ritger-Peppas and Peppas-Sahlin) models was studied to describe the drug release profile. The Weibull model was also studied. Models were tested by non-linear least-square curve fitting. A general purpose mathematical software (MATLAB) was used as an analysis tool. In addition, instead of the widely used linear fitting of log-transformed data, direct fitting was used to avoid any sort of truncation or transformation errors. The release kinetics of the beads indicated a purely relaxation-controlled delivery, referred to as case II transport. Weibull distribution showed a close fit. The release of DP from Na-Alg particulates was complete in 5-6 hours, whereas from Na-Alg hydrophobic HPMC particulate systems, release was sustained up to 10 hours. Hydrophobic HPMC with Na-Alg is an excellent matrix to formulate site-specific and controlled drug release particulate systems.
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Khalid, Ikrima, Mahmood Ahmad, Muhammad Usman Minhas, and Muhammad Sohail. "Formulation and in vitro evaluation of mucoadhesive controlled release matrix tablets of flurbiprofen using response surface methodology." Brazilian Journal of Pharmaceutical Sciences 50, no. 3 (September 2014): 493–504. http://dx.doi.org/10.1590/s1984-82502014000300007.
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The objective of the current study was to formulate mucoadhesive controlled release matrix tablets of flurbiprofen and to optimize its drug release profile and bioadhesion using response surface methodology. Tablets were prepared via a direct compression technique and evaluated for in vitro dissolution parameters and bioadhesive strength. A central composite design for two factors at five levels each was employed for the study. Carbopol 934 and sodium carboxymethylcellulose were taken as independent variables. Fourier transform infrared (FTIR) spectroscopy studies were performed to observe the stability of the drug during direct compression and to check for a drug-polymer interaction. Various kinetic models were applied to evaluate drug release from the polymers. Contour and response surface plots were also drawn to portray the relationship between the independent and response variables. Mucoadhesive tablets of flurbiprofen exhibited non-Fickian drug release kinetics extending towards zero-order, with some formulations (F3, F8, and F9) reaching super case II transport, as the value of the release rate exponent (n) varied between 0.584 and 1.104. Polynomial mathematical models, generated for various response variables, were found to be statistically significant (P<0.05). The study also helped to find the drug's optimum formulation with excellent bioadhesive strength. Suitable combinations of two polymers provided adequate release profile, while carbopol 934 produced more bioadhesion.
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Nguyen, Trung Huu, Tran Nguyen Minh An, Mahboob Alam, Duc Hoai Tran, Nghi Tran, and Dung Van Trinh. "Optimization of Pan Coating Process for Increased Efficiency of Controlled-Release Urea Fertilizer." Materiale Plastice 57, no. 4 (January 6, 2021): 333–42. http://dx.doi.org/10.37358/mp.20.4.5433.
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The goal of the research is to develop an experimental mathematical model of pan coating process effect on the biodegradable polymer and to determine optimal process parameters. The polymer solution was conducted with phosphated di-starch phosphate, polyvinyl alcohol, and polyacrylic acid and performed as material coating for the controlled-release urea fertilizer. The image analysis method has been used to determine the particle size distribution, Sauter mean diameter of the particle and layer thickness that is novel. The central composite rotatable design has been selected to determine the regression models of the process, which described the relationship between two objective variables as layer thickness, release time with angle of pan, spray flow, and coating time. The statistical analysis results indicate the fitness of model.
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Kwon, Woo Chang, Moonhee Choi, Kyung Chan Kang, and Dong Hyun Kim. "Evaluation of Ibuprofen/Montmorillonite Nano-Clay Composites as an Oral Drug Delivery System and In-Vitro Drug Release Performance." Journal of Nanoscience and Nanotechnology 21, no. 7 (July 1, 2021): 3651–55. http://dx.doi.org/10.1166/jnn.2021.19167.
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A formulation for controlled delivery of ibuprofen (IBU) involving montmorillonite (MMT) nanoclays has been proposed. The present work has investigated the beneficial effect of MMT in improving controlled delivery of IBU. The intercalation of IBU into the interlayer of MMT was studied under different processing conditions such as reaction time and initial concentration of IBU. To characterize the IBU/MMT composites, X-ray diffraction (XRD) and Fourier transform infrared spectra (FTIR) were performed. The release behavior of IBU from IBU/MMT composites have been investigated under vitro conditions using buffer media of simulated gastric fluid (pH 1.2) and simulated intestinal fluid (pH 7.4) at 37 °C. Controlled release of IBU from IBU/MMT composite has been observed during in vitro release experiments. Different mathematical models were used for fitting our experimental results, among them the best fitting was found for Higuchi equation based on the parabolic diffusion process.
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Li, Linying, Chanhwa Lee, Daniela F. Cruz, Sai Archana Krovi, Michael G. Hudgens, Mackenzie L. Cottrell, and Leah M. Johnson. "Reservoir-Style Polymeric Drug Delivery Systems: Empirical and Predictive Models for Implant Design." Pharmaceuticals 15, no. 10 (October 3, 2022): 1226. http://dx.doi.org/10.3390/ph15101226.
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Controlled drug delivery systems can provide sustained release profiles, favorable pharmacokinetics, and improved patient adherence. Here, a reservoir-style implant comprising a biodegradable polymer, poly(ε-caprolactone) (PCL), was developed to deliver drugs subcutaneously. This work addresses a key challenge when designing these implantable drug delivery systems, namely the accurate prediction of drug release profiles when using different formulations or form factors of the implant. The ability to model and predict the release behavior of drugs from an implant based on their physicochemical properties enables rational design and optimization without extensive and laborious in vitro testing. By leveraging experimental observations, we propose a mathematical model that predicts the empirical parameters describing the drug diffusion and partitioning processes based on the physicochemical properties of the drug. We demonstrate that the model enables an adequate fit predicting empirical parameters close to experimental values for various drugs. The model was further used to predict the release performance of new drug formulations from the implant, which aligned with experimental results for implants exhibiting zero-order release kinetics. Thus, the proposed empirical models provide useful tools to inform the implant design to achieve a target release profile.
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Nikravan, Goolia, Vahid Haddadi-Asl, and Mehdi Salami-Kalajahi. "Stimuli-responsive DOX release behavior of cross-linked poly(acrylic acid) nanoparticles." e-Polymers 19, no. 1 (May 29, 2019): 203–14. http://dx.doi.org/10.1515/epoly-2019-0021.
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AbstractCross-linked poly(acrylic acid) nanoparticles were synthesized via distillation precipitation polymerization of acrylic acid and ethylene glycol dimethacrylate withdifferent molar ratios. Spherical nanoparticles with diameters between 75 and 122 nm were synthesized and exhibited temperature and pH-responsive behaviors. However, this behavior was less pronounced for samples with higher cross-linking degrees. The potential of all nanoparticles as carriers for controlled release of doxorubicin (DOX) anti-cancer drug was examined at pH values of 1.2, 5.3 and 7.4. An obvious alleviation in burst release behavior and the amount of cumulative drug release was seen for all nanoparticles as the pH of the medium and the cross-linking degree of nanoparticle increased. Also kinetics of drug release was studied using mathematical models of zero-order, first-order, Higuchi, Korsmeyer-Peppas and Hixson-Crowell, where Higuchi and Korsmeyer-Peppas models best defined the kinetics of drug release.
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De Negri Atanasio, Giulia, Pier Francesco Ferrari, Roberta Campardelli, Giuseppe Firpo, Patrizia Perego, and Domenico Palombo. "Bevacizumab-Controlled Delivery from Polymeric Microparticle Systems as Interesting Tools for Pathologic Angiogenesis Diseases." Polymers 14, no. 13 (June 26, 2022): 2593. http://dx.doi.org/10.3390/polym14132593.
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This work is a comparative study among three different biocompatible and biodegradable polymers, poly(lactic-co-glycolic acid), poly(ε-caprolactone), and poly(lactic acid), used to produce microparticles for the encapsulation of bevacizumab for drug delivery purposes. All the formulations were produced using the double emulsion water-oil-water evaporation method and characterized in terms of particle mean diameter, particle size distribution, and bevacizumab entrapment efficiency. Bevacizumab cumulative release was taken into consideration to study the dissolution kinetics from the three different polymeric delivery platforms for a period of 50 days at 37 °C in phosphate buffered saline and mathematical models of the drug release kinetic were attempted in order to describe the release phenomena from the different types of the studied microparticles. Finally, cell viability on human endothelial cell line EA.hy926 was studied to define the maximum cytocompatible concentration for each microsystem, registering the mitochondrial functionality through MTS assay.
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K., Prakash Raj, Kathiresan K., and Pandian P. "A Review on Poly-Lactic-Co-Glycolic Acid as a Unique Carrier for Controlled and Targeted Delivery Drugs." Journal of Evolution of Medical and Dental Sciences 10, no. 27 (July 5, 2021): 2034–41. http://dx.doi.org/10.14260/jemds/2021/416.
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In regulated and targeted drug distribution, biodegradable polymers have played a significant portion. Poly-lactic-co-glycolic acid (PLGA) has been an important desirable polymer in tissue engineering to meet a new drug delivery system. PLGAs, show a broad spectrum of erosion cycles and have tuning mechanical characteristics. Poly-lactic-co-glycolic acid (PLGA) has been the most successful polymeric biomaterial for use in controlled drug delivery systems. PLGA has been extensively studied, in particular, in the production of equipment for controlled distribution in industrial and research applications of small molecules, protein, and other macromolecules. PLGA is biocompatible and biodegradable, exhibits a wide range of erosion times, has tunable mechanical properties and most importantly, is a FDA approved polymer. PLGA has many properties such as controlled and sustained release, low cancerinducing, long-standing biomedical applications, biocompatibility with tissues and cells, and prolonged residence time. It is otherwise called as 'Smart Polymer' because improvements are fragile to conduct PLGA that has been widely examined in industrial and academic applications to produce instruments for the target delivery of tiny molecular drugs, proteins, and other large molecules. An introduction about the chemistry, physicochemical properties, manufacturing techniques of the devices, toxicity, and the reason influencing their decrease and release of the drug was given in the present study. Mathematical modelling is a useful tool for identifying, characterizing, and predicting the mechanisms of controlled release. Mathematical modelling applied against the target from PLGA – the devices has been clarified by discussing in the review, by explaining the underlying mathematical models and how this is used. KEY WORDS Biodegradable Polymers, PLGA, Biodegradability, Macromolecules
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Yuan, Gauthier, Hungerford, Ouwerkerk, Fletcher, and Laycock. "Modelling the Controlled Release of Toxins in a Rumen Environment." Proceedings 36, no. 1 (February 12, 2020): 89. http://dx.doi.org/10.3390/proceedings2019036089.
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Pimelea poisoning in grazing cattle, also known as St George or Marree Disease, has been a long-time pestilence for the pastoral industry throughout arid regions of inland Australia. The causative species Pimelea (Thymelaeaceae), native to Queensland, New South Wales and South Australia, have been confirmed, with the secondary metabolite simplexin, a daphnane orthoester, being extracted and identified as the principal toxin. Despite the lack of effective prevention or treatment for Pimelea poisoning, naïve calves have previously been demonstrated to develop detoxification capability following prolonged low-dose simplexin intake. A variety of composites are being fabricated by encapsulating Pimelea plant material or a crude extract in biodegradable and biocompatible polyesters, aiming to develop a sustained toxin release mechanism. Studies on screening potential rumen microflora able to decompose simplexin during rumen-fluid fermentation are being conducted simultaneously. In this project, a quantification method for simplexin within these biocomposites was developed and validated utilising solid-phase extraction combined with UHPLC-Q-Orbitrap MS/MS. Reliable simplexin measurement in matrices will allow investigations into the material composition, geometry and rumen microorganism’s effects on the controlled release kinetics of simplexin in vitro. The degradation patterns of toxin delivery systems when exposed to simulated rumen environments will also be thoroughly assessed on both microscopic and chemical scales. Mathematical models of the underlying mass transport mechanisms will ultimately be established through approaches ranging from simple empirical correlations to stochastic simulations, which hold the potential to facilitate future design, optimisation, and prediction of other intra-ruminal devices based on biodegradable polymers.
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Zubenko, Denis, Alexander Petrenko, and Sergii Dulfan. "INVESTIGATION OF THE HEATING PROCESSES AND TEMPERATURE FIELD OF THE FREQUENCY-CONTROLLED ASYNCHRONOUS ENGINE BASED ON MATHEMATICAL MODELS." EUREKA: Physics and Engineering 5 (September 17, 2019): 64–72. http://dx.doi.org/10.21303/2461-4262.2019.00960.
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The study of the temperature field of the engine for non-stationary modes is done. A numerical simulation of a non-stationary thermal process using dynamic EHD, the characteristic of the rate of rise of temperatures is done. An increase in the temperature of individual parts in the idle interval, when the power of heat release is significantly reduced, is established, and the reverse of the heat flow through the air gap is established. It is shown that the EHD method, in contrast to the FEM, is self-sufficient, which determines its practical value. In various parts of the speed control range in the implementation of various laws of regulation. At the same time, the main electrical, magnetic and additional losses associated with the fundamental voltage harmonics (FVH), and mechanical losses, as well as additional electrical and magnetic losses associated with the higher voltage harmonics, change. When using serial asynchronous engines as frequency-controlled. Permissible under the conditions of heating power is significantly reduced by the power of serial engines. Depending on the synchronous speed, the reduction is from 10 % to 20 %. Given the additional overheating due to higher voltage harmonics, as well as the deterioration of the cooling conditions when adjusting the rotational speed "down" from the nominal, it seems very relevant.
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Kasiński, Adam, Monika Zielińska-Pisklak, Ewa Oledzka, Grzegorz Nałęcz-Jawecki, Agata Drobniewska, and Marcin Sobczak. "Hydrogels Based on Poly(Ether-Ester)s as Highly Controlled 5-Fluorouracil Delivery Systems—Synthesis and Characterization." Materials 14, no. 1 (December 28, 2020): 98. http://dx.doi.org/10.3390/ma14010098.
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A novel and promising hydrogel drug delivery system (DDS) capable of releasing 5‑fluorouracil (5-FU) in a prolonged and controlled manner was obtained using ε‑caprolactone‑poly(ethylene glycol) (CL-PEG) or rac‑lactide-poly(ethylene glycol) (rac‑LA-PEG) copolymers. Copolymers were synthesized via the ring-opening polymerization (ROP) process of cyclic monomers, ε‑caprolactone (CL) or rac-lactide (rac-LA), in the presence of zirconium(IV) octoate (Zr(Oct)4) and poly(ethylene glycol) 200 (PEG 200) as catalyst and initiator, respectively. Obtained triblock copolymers were characterized by nuclear magnetic resonance (NMR) and gel permeation chromatography (GPC) techniques; the structure and tacticity of the macromolecules were determined. The relationship between the copolymer structure and the reaction conditions was evaluated. The optimal conditions were specified as 140 °C and 24 h. In the next step, CL-PEG and rac-LA-PEG copolymers were chemically crosslinked using hexamethylene diisocyanate (HDI). Selected hydrogels were subjected to in vitro antitumor drug release studies, and the release data were analyzed using zero-order, first-order, and Korsmeyer-Peppas mathematical models. Controlled and prolonged (up to 432 h) 5-FU release profiles were observed for all examined hydrogels with first-order or zero-order kinetics. The drug release mechanism was generally denoted as non-Fickian transport.
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Jusu, Sandra Musu, John David Obayemi, Ali Azeko Salifu, Chukwudalu Clare Nwazojie, Vanessa Obiageli Uzonwanne, Olushola Segun Odusanya, and Winnston Oluwole Soboyejo. "PLGA-CS-PEG Microparticles for Controlled Drug Delivery in the Treatment of Triple Negative Breast Cancer Cells." Applied Sciences 11, no. 15 (July 31, 2021): 7112. http://dx.doi.org/10.3390/app11157112.
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In this study, we explore the development of controlled PLGA-CS-PEG microspheres, which are used to encapsulate model anticancer drugs (prodigiosin (PGS) or paclitaxel (PTX)) for controlled breast cancer treatment. The PLGA microspheres are blended with hydrophilic polymers (chitosan and polyethylene glycol) in the presence of polyvinyl alcohol (PVA) that were synthesized via a water-oil-water (W/O/W) solvent evaporation technique. Chitosan (CS) and polyethylene glycol (PEG) were used as surface-modifying additives to improve the biocompatibility and reduce the adsorption of plasma proteins onto the microsphere surfaces. These PLGA-CS-PEG microspheres are loaded with varying concentrations (5 and 8 mg/mL) of PGS or PTX, respectively. Scanning electron microscopy (SEM) revealed the morphological properties while Fourier transform infrared spectroscopy (FTIR) was used to elucidate the functional groups of drug-loaded PLGA-CS-PEG microparticles. A thirty-day, in vitro, encapsulated drug (PGS or PTX) release was carried out at 37 °C, which corresponds to human body temperature, and at 41 °C and 44 °C, which correspond to hyperthermic temperatures. The thermodynamics and kinetics of in vitro drug release were also elucidated using a combination of mathematical models and the experimental results. The exponents of the Korsmeyer–Peppas model showed that the kinetics of drug release was well characterized by anomalous non-Fickian drug release. Endothermic and nonspontaneous processes are also associated with the thermodynamics of drug release. Finally, the controlled in vitro release of cancer drugs (PGS and PTX) is shown to decrease the viability of MDA-MB-231 cells. The implications of the results are discussed for the development of drug-encapsulated PLGA-CS-PEG microparticles for the controlled release of cancer drugs in treatment of triple negative breast cancer.
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Hurtado, M. González, J. Rieumont Briones, Laura M. Castro González, E. Ortiz Islas, and Inti Zumeta Dube. "Kinetic studies of the release profiles of antiepileptic drug released from a nanostructured TiO2 matrix." JOURNAL OF ADVANCES IN CHEMISTRY 12, no. 4 (December 16, 2016): 4365–73. http://dx.doi.org/10.24297/jac.v12i4.2176.
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In this paper is reported the “in vitro” release kinetic studies of antiepileptic drugs released from an inorganic, titanium oxide (TiO2) porous matrix. In order to determine the drug release mechanism, the experimental values were fitted to different mathematical models: zero-order, firs-order, Higuchi, Hixson-Crowel and Peppas. TiO2 was prepared by the sol-gel method adding valproic acid (VPA) or phenytoine (DHP) during the titanium n-butoxide hydrolysis step. The drug-TiO2 systems were observed by scanning electron microscopy. The “in vitro” release experiments were performed at laboratory scale following the United States Pharmacopeia (USP) standards. The obtained materials have a morphology of nanoparticle agglomerates. The particles have different sizes with some roughness and spherical shape. Peppas model suggests for both systems, that the release mechanism is controlled by two parallel processes. The first one is by diffusion of the drug through the matrix and the second is related to a gradient of constant diffusion by ingress of the solvent in the matrix.
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Permanadewi, Indrasukma, Andri Cahyo Kumoro, Dyah Hesti Wardhani, and Nita Aryanti. "Mathematical Approach for Estimation of Alginate-Iron Salt Solutions Viscosity at Various Solid Concentrations and Temperatures." Current Research in Nutrition and Food Science Journal 9, no. 1 (April 27, 2021): 75–87. http://dx.doi.org/10.12944/crnfsj.9.1.08.
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Alginate has been widely used in the pharmaceutical industries as tablet binder and disintegrant, release agent and controlled release drug delivery system. Whereas in the food industries, alginate is generally employed as thickener, emulsifier, stabilizer, texturizer, formulation aid, firming agent, flavor adjuvant, and surface-active agent. As one of the important raw materials in the functional food preparation, iron is hard to manage due to its vulnerability to oxidization, degradation and possesses a strong unique aroma. Considering its superior coating and release properties, alginate gel can be the best choice to preserve iron from various undesirable effects. Unfortunately, there has been lack information in the published literature to estimate the effect of temperature, concentration, and stirring time on the mechanical properties of alginate. Although many mathematical models have been developed based on these factors to predict the viscosity of the alginate-Fe solutions used as feed in spray drying application, no clear information have been reported for their accuracy. This study aims to examine four physical models for their suitability in estimating alginate-Fe solution viscosity, namely the Walther, Mark Houwink, Vogel – Tamman – Fulcher (VTF), and Intrinsic models. Prior to model validation, alginate-Fe solutions containing alginate: Fe (2:1) mass ratio were prepared. They were heated to desirable temperatures (30°, 45°, 60°, and 75°C), stirred for various stirring times (0 to 60 minutes), and subjected to viscosity measurement. The results exhibited that the viscosity of alginate-Fe solution with 5% alginate concentration stirred for 15 minutes at 30°C reached 320 cP. Whereas the viscosity of Alginate-Fe solution with 1% (m/m) concentration at the same temperature and stirring time was only 250 cP. This observation suggested that a higher alginate solution concentration leads to a higher the viscosity. As expected, a higher temperature and longer stirring time resulted in the decline of the Alginate-Fe solution viscosity. Although the proposed models demonstrated the similar trend, it can be concluded that the Walther model was proven to be the most accurate model used for the prediction of the Alginate-Fe solution viscosity compared to the other models as shown by its highest R2 value, which was 0.987.
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Jayachandran, Priyanka, Suganya Ilango, Vivekananthan Suseela, Ramalingam Nirmaladevi, Mohammed Rafi Shaik, Mujeeb Khan, Merajuddin Khan, and Baji Shaik. "Green Synthesized Silver Nanoparticle-Loaded Liposome-Based Nanoarchitectonics for Cancer Management: In Vitro Drug Release Analysis." Biomedicines 11, no. 1 (January 14, 2023): 217. http://dx.doi.org/10.3390/biomedicines11010217.
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Silver nanoparticles act as antitumor agents because of their antiproliferative and apoptosis-inducing properties. The present study aims to develop silver nanoparticle-loaded liposomes for the effective management of cancer. Silver nanoparticle-encapsulated liposomes were prepared using the thin-film hydration method coupled with sonication. The prepared liposomes were characterized by DLS (Dynamic Light Scattering analysis), FESEM (Field Emission Scanning Electron Microscope), and FTIR (Fourier Transform Infrared spectroscopy). The in vitro drug release profile of the silver nanoparticle-loaded liposomes was carried out using the dialysis bag method and the drug release profile was validated using various mathematical models. A high encapsulation efficiency of silver nanoparticle-loaded liposome was observed (82.25%). A particle size and polydispersity index of 172.1 nm and 0.381, respectively, and the zeta potential of −21.5 mV were recorded. FESEM analysis revealed spherical-shaped nanoparticles in the size range of 80–97 nm. The in vitro drug release profile of the silver nanoparticle-loaded liposomes was carried out using the dialysis bag method in three different pHs: pH 5.5, pH 6.8, and pH 7.4. A high silver nanoparticle release was observed in pH 5.5 which corresponds to the mature endosomes of tumor cells; 73.32 ± 0.68% nanoparticle was released at 72 h in pH 5.5. Among the various mathematical models analyzed, the Higuchi model was the best-fitted model as there is the highest value of the correlation coefficient which confirms that the drug release follows the diffusion-controlled process. From the Korsmeyer–Peppas model, it was confirmed that the drug release is based on anomalous non-Fickian diffusion. The results indicate that the silver nanoparticle-loaded liposomes can be used as an efficient drug delivery carrier to target cancer cells of various types.
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Musuc, Adina Magdalena, Valentina Anuta, Irina Atkinson, Iulian Sarbu, Vlad Tudor Popa, Cornel Munteanu, Constantin Mircioiu, Emma Adriana Ozon, George Mihai Nitulescu, and Mirela Adriana Mitu. "Formulation of Chewable Tablets Containing Carbamazepine-β-cyclodextrin Inclusion Complex and F-Melt Disintegration Excipient. The Mathematical Modeling of the Release Kinetics of Carbamazepine." Pharmaceutics 13, no. 6 (June 21, 2021): 915. http://dx.doi.org/10.3390/pharmaceutics13060915.
Full textAbstract:
Due to its low solubility, carbamazepine (CBZ) exhibits slow and incomplete release in the gastrointestinal tract and, hence, variable pharmacokinetics and pharmacodynamic effect. Lots of methods have been devised to improve its solubility, the large number of proposed solutions being a sign that the problem is not yet satisfactorily solved. The persistent problem is that predictable release kinetics, an increased rate but within defined limits, are required to avoid high absorption variability. This paper presents a synthesis of a carbamazepine-β-cyclodextrin inclusion complex (CBZ-β-CD), the characterization of the physical mixture, CBZ, β-CD and the CBZ-β-CD inclusion complex using Fourier transform infrared spectroscopy, scanning electron microscopy, simultaneous thermal analysis and X-ray diffraction, formulation of chewable tablets, determination of the dissolution of carbamazepine in medium containing 1% sodium lauryl sulfate (LSS), and in simulated saliva (SS), mathematical modeling of release kinetics. The kinetics of total CBZ release from tablets containing CBZ-β-CD and super-disintegrant F-Melt in both SS and LSS followed two steps: a burst release in the first minutes and a slower release in intervals up to 60 min. The release in the second phase has been well described by the Higuchi and Peppas models, which advocate a controlled release by combined diffusion and with some phenomena of swelling and relaxation of the matrix generated by the crospovidone component of the F-Melt excipient.
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Suksaeree, Jirapornchai, Benjarut Chaichawawut, Muntira Srichan, Noppamon Tanaboonsuthi, Chaowalit Monton, Pattwat Maneewattanapinyo, and Wiwat Pichayakorn. "Applying design of experiments (DoE) on the properties of buccal film for nicotine delivery." e-Polymers 21, no. 1 (January 1, 2021): 566–74. http://dx.doi.org/10.1515/epoly-2021-0064.
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Abstract Design of experiments is used to optimize ratios between deproteinized natural rubber latex, Eudragit® NM 30 D, and pectin for nicotine buccal film with dependent variables as moisture content, moisture uptake, and swelling index in simulated saliva 3 and 5 h. Mathematical models were linear for moisture content and moisture uptake, while swelling index in simulated saliva 3 and 5 h was a quadratic model. Optimized polymer ratio was 0.319:0.362:0.319, respectively. Experimental values were 13.17 ± 0.92%, 3.96 ± 0.84%, 112.58 ± 22.63%, and 124.69 ± 8.01% for dependent variables, respectively. The buccal film showed high swelling at pH 7 and swelling–deswelling behaviors in a water/ethanol environment. The surface pH, weight, and thickness were 8.11, 63.28 ± 6.18 mg, and 219.87 ± 44.28 µm, respectively. Nicotine content was found as 10.22 ± 0.46 mg/4 cm2. Maximum cumulative nicotine release was 9.82 ± 0.94 mg/4 cm2. Kinetic model fitted to the Korsmeyer-Peppas model and release exponent was 0.36, representing that release mechanism was controlled by Fickian diffusion release.
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Concha, Luis, Ana Luiza Resende Pires, Angela Maria Moraes, Elizabeth Mas-Hernández, Stefan Berres, and Jacobo Hernandez-Montelongo. "Cost Function Analysis Applied to Different Kinetic Release Models of Arrabidaea chica Verlot Extract from Chitosan/Alginate Membranes." Polymers 14, no. 6 (March 10, 2022): 1109. http://dx.doi.org/10.3390/polym14061109.
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This work focuses on the mathematical analysis of the controlled release of a standardized extract of A. chica from chitosan/alginate (C/A) membranes, which can be used for the treatment of skin lesions. Four different types of C/A membranes were tested: a dense membrane (CA), a dense and flexible membrane (CAS), a porous membrane (CAP) and a porous and flexible membrane (CAPS). The Arrabidae chica extract release profiles were obtained experimentally in vitro using PBS at 37 °C and pH 7. Experimental data of release kinetics were analyzed using five classical models from the literature: Zero Order, First Order, Higuchi, Korsmeyer–Peppas and Weibull functions. Results for the Korsmeyer–Peppas model showed that the release of A. chica extract from four membrane formulations was by a diffusion through a partially swollen matrix and through a water filled network mesh; however, the Weibull model suggested that non-porous membranes (CA and CAS) had fractal geometry and that porous membranes (CAP and CAPS) have highly disorganized structures. Nevertheless, by applying an explicit optimization method that employs a cost function to determine the model parameters that best fit to experimental data, the results indicated that the Weibull model showed the best simulation for the release profiles from the four membranes: CA, CAS and CAP presented Fickian diffusion through a polymeric matrix of fractal geometry, and only the CAPS membrane showed a highly disordered matrix. The use of this cost function optimization had the significant advantage of higher fitting sensitivity.
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El-Kady, Abeer M., and Mohammad M. Farag. "Bioactive Glass Nanoparticles as a New Delivery System for Sustained 5-Fluorouracil Release: Characterization and Evaluation of Drug Release Mechanism." Journal of Nanomaterials 2015 (2015): 1–11. http://dx.doi.org/10.1155/2015/839207.
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Bioactive glass nanoparticles were synthesized and tested for the first time as a new delivery system for sustained 5-fluorouracil (5-FU) release. They were characterized by TEM, DTA, TGA, and FT-IR. The porosity % and specific surface area of glass nanoparticles were 85.59% and 378.36 m2/g, respectively. Thein vitrobioactivity evaluation confirmed that bioactive glass disks prepared from these nanoparticles could induce hydroxyapatite layer over their surfaces in simulated body fluid. Thein vitrodrug release experiment indicated that glass nanoparticles could serve as long-term local delivery vehicles for sustained 5-FU release. The release profile of 5-FU showed an initial fast release stage followed by a second stage of slower release. The initial burst release of 5-FU in the first day was about 23% (28.92 mg·L−1) of the total amount of loaded 5-FU, while the final cumulative percentage of the 5-FU released after 32 days was about 45.6% (57.31 mg·L−1) of the total amount of loaded 5-FU. The application of different mathematical models indicated that 5-FU was released by diffusion controlled mechanism and suggested that its release rate was dependent on glass particles dissolution, changes of surface area as well as diameter of glass particles, and concentration of loaded drug.
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Kotsur, Julia M., and Elena V. Flisyuk. "Modern polymers in prolonged release tablet technology." Pharmacy Formulas 2, no. 1 (March 28, 2020): 36–43. http://dx.doi.org/10.17816/phf21267.
Full textAbstract:
Currently, the delivery systems of second and third generation are of particular interest among pharmaceutical forms. Second generation pharmaceutical forms include systems with prolonged release of the active substance, third generation pharmaceutical forms include systems with controlled release. A slow continuous release of a medicinal substance may be achieved by using special excipients or by using special technologies.
For the production of tablets with prolonged release, the most common are special excipients, namely, polymers and their compositions.
The use of polymers as carriers of pharmaceutical substances used to program the kinetic frequency and location of the release is known since the middle of XX century [9]. To date, significant progress has been made in the use of polymers to prolong the release: the influence and interaction of polymers and drugs have been studied, the mechanisms of drug release have been studied, ways of programming release kinetics using various properties of polymers, etc.
In the article the modern state in the field of technology of tablets with prolonged release is considered. Advantages of prolonged release, mathematical models for description of drug forms with prolonged release are described. Technologies of tablets with prolonged release, types of delivery systems and mechanisms of release of an active pharmaceutical ingredient are considered.
The article presents modern polymers that are used in the technology of tablets with prolonged release. The classification of polymers in relation to water and to physiological liquids is presented.
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Evteev, A. V., N. V. Gorbunova, O. S. Larionova, and A. V. Bannikova. "THEORETICAL SUBSTANTIATION OF DIRECT TRANSPORT OF BIOLOGICALLY ACTIVE COMPONENTS IN CONDITIONS OF MODELED GASTROINTESTINAL TRACT." Food systems 1, no. 2 (July 11, 2018): 21–28. http://dx.doi.org/10.21323/2618-9771-2018-1-2-21-28.
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In this paper, the results of studies on the release of biological active compounds from their encapsulated forms under conditions of enzymatic hydrolysis in vitro are presented. In the phase of the model «small intestine» swelling of the capsules and their subsequent decay occurs, which allows to speak about the controlled release of encapsulated bioactive components. It was revealed that almost 90 % of the residual quantity of essential ingredients was released from the capsules in the model phase of the artificial «small intestine». At the end of the experiment, the capsules released all the encapsulated biologically active substances, regardless of the content of fish oil and phenolic compounds in them. It was noted that the poly-capsules had the greatest propensity to withstand the aggressive environment of the «model stomach» and concentrate in themselves the maximum amount of biologically active substances. Mathematical modeling confirms the direct transport of biologically active compounds and the role of the swelling of capsules in the release of biologically active compounds. two mathematical models describing the classical theory of diffusion from capsules and incorporating the material relaxation coefficient demonstrate a combination of empirical and theoretical approaches in controlling the properties of encapsulated biologically active substances. the obtained data are promising in the field of development of improved and functional food products, as well as the dry ingredients and concentrates
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Hasan, Ikramul, Shovan Paul, Sharmin Akhter, Navid Jubaer Ayon, and Md Selim Reza. "Evaluation and Optimization of Influence of Permeability Property and Concentration of Polymethacrylic Polymers on Microspheres of Metformin HCl." Dhaka University Journal of Pharmaceutical Sciences 12, no. 2 (January 12, 2014): 131–41. http://dx.doi.org/10.3329/dujps.v12i2.17611.
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Metformin HCl microspheres were prepared with the aim of increasing its bioavailability and decreasing gastrointestinal side effects by means of sustained action. Eudragit RSPO and Eudragit RLPO, polymers of different permeability characteristics were used to prepare different microspheres. Emulsification solvent evaporation technique using acetone as the internal phase and liquid paraffin as the external phase was the method of choice. Six formulations were prepared using two polymers. The effect of drug loading and polymeric property on the surface morphology, entrapment efficiency, particle size and release characteristics of the microspheres were examined. FTIR and DSC studies established compatibility of the drug with the polymers. SEM studies clearly revealed the effect of drug loading and polymeric nature on the surface morphology of the microspheres. Entrapment efficiencies were within 77.09-97.11% and particle size of all the batches were in the acceptable range. Release data were treated with different mathematical kinetic models. The drug release profile showed that Eudragit RSPO and Eudragit RLPO have opposite effect on drug release. On the other hand, increase in drug loading results in increased drug release. Kinetic modeling of in vitro dissolution profiles revealed that the drug release mechanism varies from diffusion controlled to anomalous type. Dhaka Univ. J. Pharm. Sci. 12(2): 131-141, 2013 (December) DOI: http://dx.doi.org/10.3329/dujps.v12i2.17611
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Khan, Muhammad Umar Aslam, Saiful Izwan Abd Razaq, Hassan Mehboob, Sarish Rehman, Wafa Shamsan Al-Arjan, and Rashid Amin. "Antibacterial and Hemocompatible pH-Responsive Hydrogel for Skin Wound Healing Application: In Vitro Drug Release." Polymers 13, no. 21 (October 27, 2021): 3703. http://dx.doi.org/10.3390/polym13213703.
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The treatment of successive skin wounds necessitates meticulous medical procedures. In the care and treatment of skin wounds, hydrogels produced from natural polymers with controlled drug release play a crucial role. Arabinoxylan is a well-known and widely available biological macromolecule. We produced various formulations of blended composite hydrogels (BCHs) from arabinoxylan (ARX), carrageenan (CG), and reduced graphene oxide (rGO) using and cross-linked them with an optimal amount of tetraethyl orthosilicate (TEOS). The structural, morphological, and mechanical behavior of the BCHs samples were determined using Fourier-transform infrared spectroscopy (FT-IR), Scanning electron microscope (SEM), mechanical testing, and wetting, respectively. The swelling and degradation assays were performed in phosphate-buffered saline (PBS) solution and aqueous media. Maximum swelling was observed at pH 7 and the least swelling in basic pH regions. All composite hydrogels were found to be hemocompatible. In vitro, silver sulfadiazine release profile in PBS solution was analyzed via the Franz diffusion method, and maximum drug release (87.9%) was observed in 48 h. The drug release kinetics was studied against different mathematical models (zero-order, first-order, Higuchi, Hixson–Crowell, Korsmeyer–Peppas, and Baker–Lonsdale models) and compared their regression coefficient (R2) values. It was observed that drug release follows the Baker–Lonsdale model, as it has the highest value (0.989) of R2. Hence, the obtained results indicated that, due to optimized swelling, wetting, and degradation, the blended composite hydrogel BCH-3 could be an essential wound dressing biomaterial for sustained drug release for skin wound care and treatment.
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Hosoya, Hitomi, Andrey S. Dobroff, Wouter H. P. Driessen, Vittorio Cristini, Lina M. Brinker, Fernanda I. Staquicini, Marina Cardó-Vila, et al. "Integrated nanotechnology platform for tumor-targeted multimodal imaging and therapeutic cargo release." Proceedings of the National Academy of Sciences 113, no. 7 (February 2, 2016): 1877–82. http://dx.doi.org/10.1073/pnas.1525796113.
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A major challenge of targeted molecular imaging and drug delivery in cancer is establishing a functional combination of ligand-directed cargo with a triggered release system. Here we develop a hydrogel-based nanotechnology platform that integrates tumor targeting, photon-to-heat conversion, and triggered drug delivery within a single nanostructure to enable multimodal imaging and controlled release of therapeutic cargo. In proof-of-concept experiments, we show a broad range of ligand peptide-based applications with phage particles, heat-sensitive liposomes, or mesoporous silica nanoparticles that self-assemble into a hydrogel for tumor-targeted drug delivery. Because nanoparticles pack densely within the nanocarrier, their surface plasmon resonance shifts to near-infrared, thereby enabling a laser-mediated photothermal mechanism of cargo release. We demonstrate both noninvasive imaging and targeted drug delivery in preclinical mouse models of breast and prostate cancer. Finally, we applied mathematical modeling to predict and confirm tumor targeting and drug delivery. These results are meaningful steps toward the design and initial translation of an enabling nanotechnology platform with potential for broad clinical applications.
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Yee Kuen, Cha, and Mas Jaffri Masarudin. "Chitosan Nanoparticle-Based System: A New Insight into the Promising Controlled Release System for Lung Cancer Treatment." Molecules 27, no. 2 (January 12, 2022): 473. http://dx.doi.org/10.3390/molecules27020473.
Full textAbstract:
Lung cancer has been recognized as one of the most often diagnosed and perhaps most lethal cancer diseases worldwide. Conventional chemotherapy for lung cancer-related diseases has bumped into various limitations and challenges, including non-targeted drug delivery, short drug retention period, low therapeutic efficacy, and multidrug resistance (MDR). Chitosan (CS), a natural polymer derived from deacetylation of chitin, and comprised of arbitrarily distributed β-(1-4)-linked d-glucosamine (deacetylated unit) and N-acetyl-d-glucosamine (acetylated unit) that exhibits magnificent characteristics, including being mucoadhesive, biodegradable, and biocompatible, has emerged as an essential element for the development of a nano-particulate delivery vehicle. Additionally, the flexibility of CS structure due to the free protonable amino groups in the CS backbone has made it easy for the modification and functionalization of CS to be developed into a nanoparticle system with high adaptability in lung cancer treatment. In this review, the current state of chitosan nanoparticle (CNP) systems, including the advantages, challenges, and opportunities, will be discussed, followed by drug release mechanisms and mathematical kinetic models. Subsequently, various modification routes of CNP for improved and enhanced therapeutic efficacy, as well as other restrictions of conventional drug administration for lung cancer treatment, are covered.
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Adepu, Shivakalyani, Hongrong Luo, and Seeram Ramakrishna. "Heparin-Tagged PLA-PEG Copolymer-Encapsulated Biochanin A-Loaded (Mg/Al) LDH Nanoparticles Recommended for Non-Thrombogenic and Anti-Proliferative Stent Coating." International Journal of Molecular Sciences 22, no. 11 (May 21, 2021): 5433. http://dx.doi.org/10.3390/ijms22115433.
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Drug-eluting stents have been widely implanted to prevent neointimal hyperplasia associated with bare metal stents. Conventional polymers and anti-proliferative drugs suffer from stent thrombosis due to the non-selective nature of the drugs and hypersensitivity to polymer degradation products. Alternatively, various herbal anti-proliferative agents are sought, of which biochanin A (an isoflavone phytoestrogen) was known to have anti-proliferative and vasculoprotective action. PLA-PEG diblock copolymer was tagged with heparin, whose degradation releases heparin locally and prevents thrombosis. To get a controlled drug release, biochanin A was loaded in layered double hydroxide nanoparticles (LDH), which are further encapsulated in a heparin-tagged PLA-PEG copolymer. LDH nanoparticles are synthesized by a co-precipitation process; in situ as well as ex situ loading of biochanin A were done. PLA-PEG-heparin copolymer was synthesized by esterification reaction, and the drug-loaded nanoparticles are coated. The formulation was characterized by FTIR, XRD, DSC, DLS, and TEM. In vitro drug release studies, protein adhesion, wettability, hemocompatibility, and degradation studies were performed. The drug release was modeled by mathematical models to further emphasize the mechanism of drug release. The developed drug-eluting stent coating is non-thrombogenic, and it offers close to zero-order release for 40 days, with complete polymer degradation in 14 weeks.
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Ahmed, Nusrat, Ikramul Hasan, Mohammad Saifuddin, Jakir Ahmed Chowdhury, and Md Selim Reza. "Formulation and Optimization of Carbamazepine Microspheres by 2 Factor 2 Level Central Composite Design." Bangladesh Pharmaceutical Journal 19, no. 2 (August 12, 2016): 152–60. http://dx.doi.org/10.3329/bpj.v19i2.29273.
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The present investigation was designed to prepare controlled release microspheres of carbamazepine using two polymers of different solubility and permeability characteristics, Ethocel standard 45 premium and Eudragit RL 100. The drug release profile was optimized with the aid of design of experiments (DoE). Microspheres of combined polymers were designed according to 22 factorial central composite design (CCD), taking drug loading and polymeric ratio as the independent variables. Total thirteen batches were prepared. The dependent variables were percentage of drug released in 3 hours and 6 hours and mean dissolution time (MDT). The regression parameters of the developed model and graphical interpretation for each response with statistical significance were calculated by using Minitab 17. The relationship between the experimental variables and responses were evaluated by generating response surface plots. Increased amount of Eudragit RL 100 had impact on surface morphology of prepared microspheres. It produced larger holes on the surface due to its higher permeability characteristics. Polynomial mathematical models generated for various response variables using multiple linear regression analysis, were found to be statistically significant (p < 0.05). One optimum formulation (O1) was selected based on USP specification and the second optimum formulation (O2) was selected for the maximization of MDT (hours). Batch O1 showed 22.85 % and 48.78 % drug release after 3 and 6 hours, respectively which were found to be in close agreement with those predicted by the mathematical model. Another optimum formulation, batch O2 showed MDT as 160.61 hours.Bangladesh Pharmaceutical Journal 19(2): 152-160, 2016
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Chudoba, Dorota, Monika Jażdżewska, Katarzyna Łudzik, Sebastian Wołoszczuk, Ewa Juszyńska-Gałązka, and Mikołaj Kościński. "Description of Release Process of Doxorubicin from Modified Carbon Nanotubes." International Journal of Molecular Sciences 22, no. 21 (November 5, 2021): 12003. http://dx.doi.org/10.3390/ijms222112003.
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The article discusses the release process of doxorubicin hydrochloride (DOX) from multi-wall carbon nanotubes (MWCNTs). The studies described a probable mechanism of release and actions between the surface of functionalized MWCNTs and anticancer drugs. The surface of carbon nanotubes (CNTs) has been modified via treatment in nitric acid to optimize the adsorption and release process. The modification efficiency and physicochemical properties of the MWCNTs+DOX system were analyzed by using SEM, TEM, EDS, FTIR, Raman Spectroscopy and UV-Vis methods. Based on computer simulations at pH 7.4 and the experiment at pH 5.4, the kinetics and the mechanism of DOX release from MWNT were discussed. It has been experimentally observed that the acidic pH (5.4) is appropriate for the efficient release of the drug from CNTs. It was noted that under acidic pH conditions, which is typical for the tumour microenvironment almost 90% of the drug was released in a relatively short time. The kinetics models based on different mathematical functions were used to describe the release mechanism of drugs from MWCNTs. Our studies indicated that the best fit of experimental kinetic curves of release has been observed for the Power-law model and the fitted parameters suggest that the drug release mechanism of DOX from MWCNTs is controlled by Fickian diffusion. Molecular dynamics simulations, on the other hand, have shown that in a neutral pH solution, which is close to the blood pH, the release process does not occur keeping the aggregation level constant. The presented studies have shown that MWCNTs are promising carriers of anticancer drugs that, depending on the surface modification, can exhibit different adsorption mechanisms and release.
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Malasiya, Rahul, and Tarkeshwar P. Shukla. "Formulation development and evaluation of gastroretentive mucoadhesive tablets of glimepiride using natural polymers." Journal of Drug Delivery and Therapeutics 10, no. 4-s (August 15, 2020): 153–59. http://dx.doi.org/10.22270/jddt.v10i4-s.4264.
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Glimepiride, a third-generation sulfonylurea is poorly soluble anti-diabetic drug. Currently, the use of natural gums and mucilage is of increasing importance in pharmaceutical formulations as valuable drug excipients. Natural plant-based materials are economic, free of side effects, biocompatible and biodegradable. The development of mucoadhesive sustained release drug delivery system is recommended in order to enhance the bioavailability. A mucoadhesive tablets were developed using the natural polymer sodium alginate and gum tragacanth. Mucoadhesion is a complex phenomenon which involves wetting, adsorption and interpenetration of polymer chains. The tablets of glimepiride were prepared by direct compression method. Pre-compression parameters were evaluated. The tablets were evaluated for post-compression parameters such as thickness, hardness, average weight, friability and In vitro release studies. All the compositions were resulted in adequate pharmacopoeial limits. The varying concentration of polymers was found to affect on in-vitro drug release and mucoadhesive strength. In vitro drug release of gastro retentive tablet of glimepiride shown that the formulation F5 was found to be the best formulation as it releases 98.78%. Glimepiride in a sustain release manner for an extended period of time (up to 12 hrs). The release data was fitted to various mathematical models such as higuchi, korsmeyer-peppas, first order and zero order to evaluate the kinetics and mechanism of the drug release. Prepared tablets of glimepiride may prove to be a potential candidate for safe and effective controlled drug delivery over an extended period of time for gastro retentive drug delivery system.
Keywords: Glimepiride, Gastro retentive, Anti-diabetic drug, Direct compression method
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Pepic, Dragana, Darinka Andjelkovic, Marija Nikolic, Svetlana Grujic, and Jasna Djonlagic. "Optimization of preparation conditions of poly(ε-caprolactone) microspheres for controlled release of carbamazepine." Chemical Industry 64, no. 6 (2010): 491–502. http://dx.doi.org/10.2298/hemind101117073p.
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Poly (?-caprolactone), PCL, is an aliphatic polyester suitable for controlled drug release due to its biodegradability, biocompatibility, non-toxicity and high permeability to many therapeutic drugs. This study investigates the effect of the preparation parameters on the size and the morphology of the PCL microspheres and on the release profile of carbamazepine from these microspheres. The PCL microspheres were prepared using oil-in-water (o/w) emulsion solvent evaporation method with the poly(vinyl alcohol), PVA, as the emulsion stabilizer. The influence of the stirring rate applied during the emulsion formation, the homogenization time and the emulsifier concentration on diameter and size distribution of the microspheres was analyzed by scanning electron microscope (SEM). The initial emulsion was formed applying high stirring rates of 10000, 18000 and 23000 rpm, for homogenization times: 5, 10 and 15 min. The diameter was strongly influenced by the stirring rate, and the average particle size decreased from 9.2 to 2.8 ?m with the increase of the stirring rate. Increasing the amount of PVA in the water phase from 0.2 to 1 mass% improved stabilization of the oil droplets and led to a slight decrease of the average particle diameter. Drug-loaded microspheres were prepared by the same technique using different amounts of carbamazepine (10 and 15 mass%), under given conditions (1 mass% PVA, stirring rate of 18000 rpm for a period of 5 min of emulsion formation). Additionally, microspheres were prepared by applying low stirring rate of 1000 rpm with 10 and 15 mass% of the drug. The SEM analysis showed that microspheres created with 18000 rpm stirring rate, had average diameters of 3-4 ?m, and the microspheres prepared with 1000 rpm stirring rate were larger than 100 ?m. It was also observed that, in the case of the large microspheres, carbamazepine was deposited on their surfaces, while the small microspheres had smooth surfaces without observable drug crystals. The encapsulation efficiency and the release behavior of the carbamazepine were examined using high performance liquid chromatography-ultraviolet spectroscopy (HPLC-UV). The drug encapsulation efficiencies were in the range from 69 to 81%, and were increasing with the increase of the amount of carbamazepine in both series. In vitro release experiments were carried out in the phosphate buffer solution (pH 7) at 37?C. The release rate was influenced by the microspheres size and morphology. The larger microspheres released more carbamazepine (85-95%) compared to the small ones (50-65%) for the same period. This behavior was attributed to the different drug distribution in the PCL matrix. Different mathematical models were used to describe drug release kinetics. It was concluded that the mechanism of the carbamazepine release from the microspheres was diffusion-controlled, independent on the type of microspheres. The kinetic parameters showed that the release of carbamazepine was slower from the smaller microspheres, probably as a result of more even distribution of the drug in the polymer matrix.
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Ansary, Johura, Amit Kumar Chaurasiya, and KM Bashirul Huq. "Formulation and evaluation of metformin HCl floating microspheres." Asian Journal of Medical and Biological Research 1, no. 3 (February 23, 2016): 396–405. http://dx.doi.org/10.3329/ajmbr.v1i3.26445.
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The purpose of the present investigation was the preparation and evaluation of gastro-retentive floating drug delivery system for anti-diabetic drug metformin hydrochloride that would retain the drug in stomach and continuously release the drug in controlled manner up to a predetermined time leading to improve bioavailability. The microspheres were prepared by oil-in-oil emulsion solvent evaporation technique using ethyl cellulose, methacrylic acid copolymer (Eudragit RS100, Eudragit RSPO and Eudragit RLPO). The dried floating microspheres were evaluated for percentage yield (%), actul drug content (%), drug entrapment efficiency, floating behavior, scanning electron microscopy and in vitro drug release studies. The microspheres were found spherical, porous and free flowing with a size range. Compatibility studies were performed by fourier transform infra-redand (FTIR) and differential thermal analysis (DTA) techniques. The DTA and FTIR data stated that drug and excipient were compatible. In-vitro release kinetics were studied in different mathematical release models following the zero order, Higuchi and Korsemeyer to find out the linear relationship and release rate of drug. The drug might be released by both diffusion and erosion as the correlation coefficient (R2) best fitted with Korsemeyer model and release exponent (n) was 0.45-0.89. In most cases good in vitro floating behavior was observed and a broad variety of drug release pattern was achieved by variation of the polymer which optimized to match target release profile. The developed floating microspheres of metformin hydrochloride may be used in clinic for prolonged drug release in stomach for at least 8 hrs, thereby improving the bioavailability and patient compliance.Asian J. Med. Biol. Res. December 2015, 1(3): 396-405
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Trofin, Marin-Aurel, Stefania Racovita, Silvia Vasiliu, Ana-Lavinia Vasiliu, and Marcela Mihai. "Porous Crosslinked Zwitterionic Microparticles Based on Glycidyl Methacrylate and N-Vinylimidazole as Possible Drug Delivery Systems." International Journal of Molecular Sciences 23, no. 23 (November 30, 2022): 14999. http://dx.doi.org/10.3390/ijms232314999.
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Crosslinked porous microparticles have received great attention as drug delivery systems lately due to their unique set of properties: the capability to form various polymer–drug combinations, low immunogenicity, patient compliance and ability to release drugs in a delayed or controlled manner. Moreover, polymers with betaine groups have shown some unique features such as antifouling, antimicrobial activity, biocompatibility and strong hydration properties. Herein, novel porous zwitterionic microparticles were prepared in two stages. The first step involves the synthesis of porous microparticles based on glycidyl methacrylate, N-vinylimidazole and triethyleneglycol dimethacrylate using the suspension polymerization technique, the second step being the synthesis of zwitterionic porous microparticles by polymer–analogous reaction in presence of sodium monochloroacetate as betainization agent. Both types of microparticles were characterized structurally and morphologically by FT-IR spectroscopy, energy dispersive X-ray analysis, scanning electron microscopy, dynamic vapors sorption and mercury porosimetry. The tetracycline loading into crosslinked and zwitterionic microparticles was also performed, the maximum tetracycline loading capacities being 87 mg/g and 135 mg/g, respectively. The drug release mechanism, elucidated by various mathematical models, is controlled by both diffusion and swelling processes as a function of the zwitterionic and/or porous microparticle structure. Both types of microparticles presented antibacterial activity against the two reference strains used in this study: Escherichia coli and Staphylococcus aureus.
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Hamedi, Hamid, Sara Moradi, Alan E. Tonelli, and Samuel M. Hudson. "Preparation and Characterization of Chitosan–Alginate Polyelectrolyte Complexes Loaded with Antibacterial Thyme Oil Nanoemulsions." Applied Sciences 9, no. 18 (September 19, 2019): 3933. http://dx.doi.org/10.3390/app9183933.
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Biomedical industries are attempting to utilize natural materials, as they are bio-compatible, non-toxic, and show bioactive properties, like antimicrobial activity. In this study, natural polyelectrolyte complexed chitosan/alginate films (PECs) were prepared via a casting/solvent evaporation technique, and their characteristics and drug release properties were investigated. PEC films made with two different overall polymer contents, 0.4 and 1 w/v%, were loaded with thyme oil nanoemulsion as drug carrier. The structure of the films was studied by FTIR and optical and scanning electron microscopy. Prepared PEC films had good mechanical and water vapor permeability properties. Release of the thyme oil from the pH-sensitive PEC films (TM-PEC) was detected and followed by UV spectroscopy. The results indicated that the drug release rate of TM-PEC films was the fastest when the chitosan content was 1 %w/v, and various mathematical models were analyzed for investigating the drug release mechanism. Antibacterial tests were performed by counting the number of surviving gram-negative and gram-positive bacteria. The in vitro test indicated the limitation Escherichia coli (E. coli) and Staphylococcus aureus (S.aureus) growth in the presence of TM-PEC films. The MTT test showed more cell viability of the TM-PEC film in comparison with that of the PEC film without TM. Based on the measured physical and antibacterial properties, the chitosan–alginate PEC films loaded with antibacterial essential oils can be considered for biomedical applications, such as wound dressings or controlled release systems.
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Padinjarathil, Himabindu, Srikrishna Mudradi, Rajalakshmi Balasubramanian, Carmelo Drago, Sandro Dattilo, Nikhil K. Kothurkar, and Prasanna Ramani. "Design of an Antibiotic-Releasing Polymer: Physicochemical Characterization and Drug Release Patterns." Membranes 13, no. 1 (January 12, 2023): 102. http://dx.doi.org/10.3390/membranes13010102.
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Conventional drug delivery has its share of shortcomings, especially its rapid drug release with a relatively short duration of therapeutic drug concentrations, even in topical applications. Prolonged drug release can be effectively achieved by modifying the carrier in a drug delivery system. Among the several candidates for carriers studied over the years, poly (ether ether ketone), a biocompatible thermoplastic, was chosen as a suitable carrier. Its inherent hydrophobicity was overcome by controlled sulfonation, which introduced polar sulfonate groups onto the polymer backbone. Optimization of the sulfonation process was completed by the variation of the duration, temperature of the sulfonation, and concentration of sulfuric acid. The sulfonation was confirmed by EDS and the degree of sulfonation was determined by an NMR analysis (61.6% and 98.9%). Various physical properties such as morphology, mechanical strength, and thermal stability were studied using scanning electron microscopy, tensile testing, and thermogravimetric analysis. Cytotoxicity tests were performed on the SPEEK samples to study the variation in biocompatibility against a Vero cell line. The drug release kinetics of ciprofloxacin (CP) and nalidixic acid sodium salt (NA)-loaded membranes were studied in deionized water as well as SBF and compared against the absorbance of standardized solutions of the drug. The data were then used to determine the diffusion, distribution, and permeability coefficients. Various mathematical models were used to fit the obtained data to establish the order and mechanism of drug release. Studies revealed that drug release occurs by diffusion and follows zero-order kinetics.
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Casalini, Tommaso, and Giuseppe Perale. "From Microscale to Macroscale: Nine Orders of Magnitude for a Comprehensive Modeling of Hydrogels for Controlled Drug Delivery." Gels 5, no. 2 (May 15, 2019): 28. http://dx.doi.org/10.3390/gels5020028.
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Because of their inherent biocompatibility and tailorable network design, hydrogels meet an increasing interest as biomaterials for the fabrication of controlled drug delivery devices. In this regard, mathematical modeling can highlight release mechanisms and governing phenomena, thus gaining a key role as complementary tool for experimental activity. Starting from the seminal contribution given by Flory–Rehner equation back in 1943 for the determination of matrix structural properties, over more than 70 years, hydrogel modeling has not only taken advantage of new theories and the increasing computational power, but also of the methods offered by computational chemistry, which provide details at the fundamental molecular level. Simulation techniques such as molecular dynamics act as a “computational microscope” and allow for obtaining a new and deeper understanding of the specific interactions between the solute and the polymer, opening new exciting possibilities for an in silico network design at the molecular scale. Moreover, system modeling constitutes an essential step within the “safety by design” paradigm that is becoming one of the new regulatory standard requirements also in the field-controlled release devices. This review aims at providing a summary of the most frequently used modeling approaches (molecular dynamics, coarse-grained models, Brownian dynamics, dissipative particle dynamics, Monte Carlo simulations, and mass conservation equations), which are here classified according to the characteristic length scale. The outcomes and the opportunities of each approach are compared and discussed with selected examples from literature.
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Scomoroscenco, Cristina, Mircea Teodorescu, Adina Raducan, Miruna Stan, Sorina Nicoleta Voicu, Bodgan Trica, Claudia Mihaela Ninciuleanu, et al. "Novel Gel Microemulsion as Topical Drug Delivery System for Curcumin in Dermatocosmetics." Pharmaceutics 13, no. 4 (April 7, 2021): 505. http://dx.doi.org/10.3390/pharmaceutics13040505.
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Gel microemulsion combines the advantages of the microemulsion, which can encapsulate, protect and deliver large quantities of active ingredients, and the gel, which is so appreciated in the cosmetic industry. This study aimed to develop and characterize new gel microemulsions suitable for topical cosmetic applications, using grape seed oil as the oily phase, which is often employed in pharmaceuticals, especially in cosmetics. The optimized microemulsion was formulated using Tween 80 and Plurol® Diisostearique CG as a surfactant mix and ethanol as a co-solvent. Three different water-soluble polymers were selected in order to increase the viscosity of the microemulsion: Carbopol® 980 NF, chitosan, and sodium hyaluronate salt. All used ingredients are safe, biocompatible and biodegradable. Curcumin was chosen as a model drug. The obtained systems were physico-chemically characterized by means of electrical conductivity, dynamic light scattering, polarized microscopy and rheometric measurements. Evaluation of the cytotoxicity was accomplished by MTT assay. In the final phase of the study, the release behavior of Curcumin from the optimized microemulsion and two gel microemulsions was evaluated. Additionally, mathematical models were applied to establish the kinetic release mechanism. The obtained gel microemulsions could be effective systems for incorporation and controlled release of the hydrophobic active ingredients.
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Kapil Jalodiya, Sourabh Jain, and Karunakar Shukla. "Formulation and evaluation of gastro-retentive floating tablets of terbinafine." GSC Biological and Pharmaceutical Sciences 13, no. 1 (November 30, 2020): 257–66. http://dx.doi.org/10.30574/gscbps.2020.13.1.0310.
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Gastro-retentive dosage forms enable prolonged and continuous input of the drug to the upper parts of the gastrointestinal tract and improve the bioavailability of medications those are characterized by a narrow absorption window. The purpose of this research was to develop a novel gastro retentive drug delivery system based on direct compression method for sustained delivery of active agent to improve the bioavailability, reduce the number of doses and to increase patient compliance. Gastro retentive floating tablets of terbinafine were prepared by direct compression method using altered concentrations of HPMC K4, HPMC K15 and PVP K30 as polymers. The prepared tablets of terbinafine were evaluated tablet hardness, uniformity of weight, friability, uniformity of content, in vitro buoyancy test, swelling index, in vitro dissolution study and stability study. All the compositions were resulted in adequate Pharmacopoeial limits. Compatibility studies was execution during FTIR shown that there was absence of probable chemical interaction between pure drug and excipients. The varying concentration of gas generating agent and polymers was found to affect on in-vitro drug release and floating lag time. In vitro drug release of floating gastro retentive tablet of terbinafine shown that the formulation F5 was found to be the best formulation as it releases 96.22% terbinafine in a controlled manner for an extended period of time (up to 480 min). The release data was fitted to various mathematical models such as Higuchi, Korsmeyer-Peppas, First order and Zero order to evaluate the kinetics and mechanism of the drug release. Prepared floating tablets of terbinafine may prove to be a potential candidate for safe and effective controlled drug delivery over an extended period of time for gastro retentive drug delivery system.
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Ward, Sophia A., Roy N. Kirkwood, Kate J. Plush, Sadikalmahdi Abdella, Yunmei Song, and Sanjay Garg. "Development of a Novel Vaginal Drug Delivery System to Control Time of Farrowing and Allow Supervision of Piglet Delivery." Pharmaceutics 14, no. 2 (January 31, 2022): 340. http://dx.doi.org/10.3390/pharmaceutics14020340.
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The swine industry has evolved significantly in the recent decades, but this has come at considerable expense to piglet survival. Breeding sows for greater prolificacy has been accompanied by a greater proportion of piglets being born underweight, of lower vigor, and higher susceptibility to early mortality. Inducing sows to farrow during working hours has the potential to increase piglet survivability, but non-therapeutic injectable products are often discouraged on farms. We aimed to design and develop a novel vaginal drug delivery system (NVDDS) that could reliably trigger luteolysis and induce parturition. To achieve this, two vaginal tablets containing the luteolytic agent cloprostenol were formulated to be inserted together: one would release constituents immediately on insertion (immediate release; IR) and the other would release cloprostenol in a controlled manner (controlled release; CR). The two formulations (IR and CR) were evaluated for drug release, swelling and bio-adhesion in conditions simulating the sow vaginal environment. The IR tablet released the drug completely for 5 min whereas the CR tablet took 5 h to release 50% of the drug. Furthermore, the release kinetics were evaluated by fitting the dissolution profiles into different mathematical models. Both IR and CR tablets were best fitted by the Makoid–Banakar model which assumes release by summation of different mechanisms. The performance of the optimized formulations was studied in vivo with 161 Large White x Landrace sows of varying parity (0–5). The sows were assigned to five groups. Group 1 (SI) received a single vulval injection of cloprostenol at 0700 h (n = 32), group 2 (SDI) received the same dose split in two parts, at 0700h and 1300h (n = 33). Group 3 (IRT) animals were administered an IR tablet at 0700h (n = 32), while group 4 (IRCRT) received both IR and CR tablets at 0700 h (n = 33). Group 5 was untreated and served as a control (n = 32). The interval to farrowing was longer (p < 0.001) for controls than for treated sows, but there were no differences among cloprostenol treatments for timing of farrowing. The finding confirms the efficacy of the NVDDS for induction of farrowing in sows.
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Patle, Bharti, Vivek Jain, Shradha Shende, and Prabhat Kumar Jain. "Formulation Development and Evaluation of Sustain Release Gastroretentive Floating Tablets of Prochlorperazine Dimaleate." Journal of Drug Delivery and Therapeutics 9, no. 4-s (August 15, 2019): 445–50. http://dx.doi.org/10.22270/jddt.v9i4-s.3353.
Full textAbstract:
Floating drug delivery systems are the gastroretentive forms that precisely control the release rate of target drug to a specific site which facilitate an enormous impact on health care. The purpose of this research was to develop a novel gastro retentive drug delivery system based on direct compression method for sustained delivery of active agent to improve the bioavailability, reduce the number of doses and to increase patient compliance. Gastro retentive floating tablets of Prochlorperazine dimaleate (PCZ) were prepared by direct compression method using altered concentrations of HPMC K4, HPMC K15 and PVP K30 as polymers. The prepared tablets of PCZ were evaluated for hardness, thickness, friability, weight variation, drug content uniformity, buoyancy lag time, total floating time, in-vitro dissolution study, etc. All the compositions were resulted in adequate Pharmacopoeial limits. Compatibility studies was execution during FTIR shown that there was absence of probable chemical interaction between pure drug and excipients. The varying concentration of gas generating agent and polymers was found to affect on in-vitro drug release and floating lag time. In vitro drug release of floating gastro retentive tablet of PCZ shown that the formulation F9 was found to be the best formulation as it releases 98.89% in a controlled manner for an extended period of time (up to 12 hrs). The release data was fitted to various mathematical models such as Higuchi, Korsmeyer-Peppas, First order and Zero order to evaluate the kinetics and mechanism of the drug release. The optimized formulation (F9) showed no significant change in physical appearance, drug content, floating lag time, in vitro dissolution studies after 75%±5% RH at 40±20C relative humidity for 6 months. Prepared floating tablets of PCZ may prove to be a potential candidate for safe and effective controlled drug delivery over an extended period of time for gastro retentive drug delivery system.
Keywords: Prochlorperazine dimaleate, Floating tablet, Gastro retentive, Total floating time.
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Al-Arjan, Wafa Shamsan, Muhammad Umar Aslam Khan, Hayfa Habes Almutairi, Shadia Mohammed Alharbi, and Saiful Izwan Abd Razak. "pH-Responsive PVA/BC-f-GO Dressing Materials for Burn and Chronic Wound Healing with Curcumin Release Kinetics." Polymers 14, no. 10 (May 11, 2022): 1949. http://dx.doi.org/10.3390/polym14101949.
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Polymeric materials have been essential biomaterials to develop hydrogels as wound dressings for sustained drug delivery and chronic wound healing. The microenvironment for wound healing is created by biocompatibility, bioactivity, and physicochemical behavior. Moreover, a bacterial infection often causes the healing process. The bacterial cellulose (BC) was functionalized using graphene oxide (GO) by hydrothermal method to have bacterial cellulose-functionalized-Graphene oxide (BC-f-GO). A simple blending method was used to crosslink BC-f-GO with polyvinyl alcohol (PVA) by tetraethyl orthosilicate (TEOS) as a crosslinker. The structural, morphological, wetting, and mechanical tests were conducted using Fourier-transform infrared spectroscopy (FTIR), Scanning electron microscope (SEM), water contact angle, and a Universal testing machine (UTM). The release of Silver-sulphadiazine and drug release kinetics were studied at various pH levels and using different mathematical models (zero-order, first-order, Higuchi, Hixson, Korsmeyer–Peppas, and Baker–Lonsdale). The antibacterial properties were conducted against Gram-positive and Gram-negative severe infection-causing pathogens. These composite hydrogels presented potential anticancer activities against the U87 cell line by an increased GO amount. The result findings show that these composite hydrogels have physical-mechanical and inherent antimicrobial properties and controlled drug release, making them an ideal approach for skin wound healing. As a result, these hydrogels were discovered to be an ideal biomaterial for skin wound healing.
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Husseini, Ghaleb A., and William G. Pitt. "The Use of Ultrasound and Micelles in Cancer Treatment." Journal of Nanoscience and Nanotechnology 8, no. 5 (May 1, 2008): 2205–15. http://dx.doi.org/10.1166/jnn.2008.225.
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The high toxicity of potent chemotherapeutic drugs like Doxorubicin (Dox) limits the therapeutic window in which they can be applied. This window can be expanded by controlling the drug delivery in both space and time such that non-targeted tissues are not adversely affected. Recent research has shown that ultrasound (US) can be used to control the release of Dox and other hydrophobic drugs from polymeric micelles in both time and space. It has also been shown using an in vivo rat tumor model that Dox activity can be enhanced by ultrasound in one region, while in an adjacent region there is little or no effect of the drug. In this article, we review the in vivo and in vitro research being conducted in the area of using ultrasound to enhance and target micellar drug delivery to cancerous tissues. Additionally, we summarize our previously published mathematical models that attempt to represent the release and re-encapsulation phenomena of Dox from Pluronic® P105 micelles upon the application of ultrasound. The potential benefits of such controlled chemotherapy compels a thorough investigation of the role of ultrasound (US) and the mechanisms by which US accomplishes drug release and/or enhances drug potency. Therefore we will summarize our findings related to the mechanism involved in acoustically activated micellar drug delivery to tumors.
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Khan, Muhammad Umar Aslam, Iqra Iqbal, Mohamed Nainar Mohamed Ansari, Saiful Izwan Abd Razak, Mohsin Ali Raza, Amna Sajjad, Faiza Jabeen, Mohd Riduan Mohamad, and Norhana Jusoh. "Development of Antibacterial, Degradable and pH-Responsive Chitosan/Guar Gum/Polyvinyl Alcohol Blended Hydrogels for Wound Dressing." Molecules 26, no. 19 (September 30, 2021): 5937. http://dx.doi.org/10.3390/molecules26195937.
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The present research is based on the fabrication preparation of CS/PVA/GG blended hydrogel with nontoxic tetra orthosilicate (TEOS) for sustained paracetamol release. Different TEOS percentages were used because of their nontoxic behavior to study newly designed hydrogels’ crosslinking and physicochemical properties. These hydrogels were characterized using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and wetting to determine the functional, surface morphology, hydrophilic, or hydrophobic properties. The swelling analysis in different media, degradation in PBS, and drug release kinetics were conducted to observe their response against corresponding media. The FTIR analysis confirmed the components added and crosslinking between them, and surface morphology confirmed different surface and wetting behavior due to different crosslinking. In various solvents, including water, buffer, and electrolyte solutions, the swelling behaviour of hydrogel was investigated and observed that TEOS amount caused less hydrogel swelling. In acidic pH, hydrogels swell the most, while they swell the least at pH 7 or higher. These hydrogels are pH-sensitive and appropriate for controlled drug release. These hydrogels demonstrated that, as the ionic concentration was increased, swelling decreased due to decreased osmotic pressure in various electrolyte solutions. The antimicrobial analysis revealed that these hydrogels are highly antibacterial against Gram-positive (Staphylococcus aureus and Bacillus cereus) and Gram negative (Pseudomonas aeruginosa and Escherichia coli) bacterial strains. The drug release mechanism was 98% in phosphate buffer saline (PBS) media at pH 7.4 in 140 min. To analyze drug release behaviour, the drug release kinetics was assessed against different mathematical models (such as zero and first order, Higuchi, Baker–Lonsdale, Hixson, and Peppas). It was found that hydrogel (CPG2) follows the Peppas model with the highest value of regression (R2 = 0.98509). Hence, from the results, these hydrogels could be a potential biomaterial for wound dressing in biomedical applications.