Dissertations / Theses: 'Drug Delivery Applications'

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Banerjee, Abhishek. "Functionalizable Biodegradable Polyesters for Drug Delivery Applications." University of Akron / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=akron1335240206.

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Tamames, Tabar Cristina. "Metal-organic frameworks for drug delivery applications." Thesis, Versailles-St Quentin en Yvelines, 2014. http://www.theses.fr/2014VERS0006/document.

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Ce travail de thèse est centré sur l’étude d’un nouveau type de matériau, les solideshybrides cristallins MOFs (ou Metal-Organic Frameworks) comme systèmes devectorisation de médicaments.Tout d’abord, les MOFs ont été synthétisés à l’échelle nanométrique (NP), en utilisant desméthodes biocompatibles, quand possible. Leur cytotoxicité, ainsi que celle de leursligands constitutifs, a été évaluée par le test MTT sur des macrophages murins (J774) etdu carcinome cervical (HeLa). Nous avons pu constater: (i) une faible cytotoxicité desMOFs, comparable à celle d’autres particules commercialisées, (ii) une influenceimportante de la composition du MOF (ordre de toxicité: Fe
In this work, a new type of particles denoted as MOFs or Metal-Organic Frameworks, havebeen studied as a new drug carriers.First, they were synthesised at the nanoscale (NPs) using, when possible, biofriendlymethods. Their cytotoxicity, as well as that from their constitutive linkers, was evaluatedby the MTT test in murine macrophage (J774) and in cervix carcinoma (HeLa) cell lines,observing: (i) a low cytotoxicity of MOFs, comparable with other described particulatedsystems, (ii) a strong influence of the composition (toxicity order: Fe
En este trabajo, se han estudiado un nuevo tipo de partículas denominadas MOFs oMetal-Organic Frameworks como transportadores de fármacos.Primero, se sintetizaron en escala nanométrica (NP) sustituyendo los disolventes tóxicoscuando fuese posible. Se evaluó su citotoxicidad, así como la de sus ligandos, mediante eltest de MTT en las líneas celulares J774 (macrófagos murinos) y en HeLa (carcinoma decérvix), observando: (i) una baja citotoxicidad de los MOFs, comparable a otros sistemasparticulados, (ii) una fuerte influencia de su composición (orden de toxicidad: Fe

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3

Frost, S. J. "Analytical applications of liposomes." Thesis, University of Surrey, 1994. http://epubs.surrey.ac.uk/2745/.

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Liposomes have established roles in drug delivery and cell membrane studies. Amongst other applications; they can also be used as analytical reagents, particularly in immunoassays. Liposomal immunoassays have potential advantages over alternatives; including sensitivity, speed, simplicity and relative reagent stability. The aim of these studies was to develop and evaluate novel examples of these assays. When liposomes entrapped the dye, Sulphorhodamine B, a shift in its maximum absorption wavelength compared to free dye was observed. This was attributed to dimerization of the dye at high concentrations. If the liposomes were disrupted, the released dye was diluted into the external buffer, and the dye's absorption spectrum reverted to that of free dye. After optimization of dye entrapment, immunoassays were developed using these liposomes. Albumin-coated liposomes were used in a model assay to measure serum albumin. This assay employed complement-mediated immunolysis, commonly used in liposomal immunoassays. The liposomes were lysed by anti-albumin and complement, and this could be competitively inhibited by serum albumin. To improve sensitivity, Fab' anti-albumin liposomes were prepared. These enabled measurement of urinary albumin by a complement-mediated immunoassay, but using a sandwich technique. Anti-albumin (intact) liposomes were shown to precipitate on gentle centrifugation after reaction with albumin. They were applied as a solid phase reagent in an heterogeneous immunoassay, using radioimmunoassay for urinary microalbumin as a model assay. Liposomes containing Sulphorhodamine B were also used in a more novel assay; for serum anticardiolipin antibodies. Cardiolipin-containing liposomes were prepared. These were lysable using magnesium ions. Anticardiolipin antibodies (IgG) were found to augment this lysis, enabling their estimation. Similar imprecision and acceptable correlation with a commercial enzyme-linked immunosorbent assay (ELISA) were obtained. The findings demonstrate Sulphorhodamine B release can be used as a marker in homogeneous colorimetric liposomal immunoassays; both in model assays and in potentially more useful clinical biochemistry applications.

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Ostroha, Jamie L. Lowman Anthony M. Dan Nily. "PEG-based degradable networks for drug delivery applications /." Philadelphia, Pa. : Drexel University, 2006. http://dspace.library.drexel.edu/handle/1860%20/842.

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Kumar, Dhiraj. "Co-Functionalised Gold Nanoparticles for Drug Delivery Applications." Thesis, Ulster University, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.649271.

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Benzeval, Ian. "Development of responsive polymers for drug delivery applications." Thesis, University of Bath, 2009. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.500696.

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In this thesis, glucose responsive hydrogels based on cross-linked dextran molecules were studied to determine the diffusion rate of an insulin analogue. Investigations of the interaction between concanavalin A and dextran, both in free solution and in the form of glucose responsive hydrogels were conducted. The free solution results have shown that there is an increase of association constant between concanavalin A and dextran when the molecular mass of the dextran is increased. Free solution viscometric tests have shown that increasing the molecular mass or the concentration of the dextran increases the viscosity. The hydrogels have been shown to form for dextrans of molecular mass 43kD or greater. Experiments conducted with hydrogel membranes in a diffusion cell have shown that the batch to batch reproducibility of hydrogel transport properties is low. However, clear evidence of glucose enhanced transport was obtained and these results were compared with predictions obtained from a theoretical model of gel permeability that accounts for competitive displacement of affinity cross links. Oscillatory rheological tests of gelation mixtures which showed an increase in complex viscosity at the gel point with increasing molecular mass of dextran were in agreement with empirical observations that gels formed from the highest molecular mass dextrans were more physically robust and easier to handle. Swelling rate experiments have shown that the rate of hydration of a hydrogel in the presence of glucose is decreased due to the osmotic pressure of the glucose. This work has shown that the multivalent nature of concanavalin A may not be a necessary pre-requisite for this type of hydrogel due to spatial constraints decreasing the number of potential affinity bonds per tetramer. In-house production of more tightly defined dextrans might be expected to reduce heterogeneity and improve the reproducibility of this type of hydrogel membrane.

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Mitragotri, Samir. "Ultrasound-mediated transdermal drug delivery : mechanisms and applications." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/11263.

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Green, Da'Sean Edward. "Trehalose-Stabilized Polymer Assemblies for Drug Delivery Applications." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu150332742091042.

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9

Roberts, Rose A. "Polymer Nanoparticle Characterization and Applications for Drug Delivery." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/104384.

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Nanoparticle usage continues to increase in everyday products, from cosmetics to food preservation coatings, drug delivery to polymer fillers. Their characterization and synthesis is of utmost importance to ensure safety and improved product quality. Nanoparticles can be sourced naturally or synthetically fabricated. Cellulose nanocrystals (CNCs) are rod-like nanoparticles that can be isolated from nature. Reliable methods of characterization are necessary to ensure quality control. However, their physical characteristics cause challenges for imaging under transmission electron microscopy (TEM) with a high enough resolution for dimensional analysis. Heavy metal staining such as radioactive uranyl acetate is often used to increase contrast and TEM sample substrate preparation techniques often use expensive equipment such as glow discharge in order to prevent CNC agglomeration. A method to reliably produce TEM images of CNCs without using radioactive stains or expensive glow discharge equipment was developed, using a vanadium-based stain branded NanoVan® and bovine serum albumin to keep CNCs dispersed while drying on the TEM substrate. Due to their aspect ratio, there is also concern of toxicity to the lungs. The concentration of CNCs in air in production facilities must be monitored, but there is currently no method tailored to CNCs. A method using UV-vis spectroscopy, dynamic light scattering, TEM, and scanning mobility particle sizer in conjunction with impinger collectors was developed for monitoring aerosolized CNC concentration. Synthetic nanoparticles are often used for controlled drug delivery systems. A new peptide drug termed αCT1 has been shown to interact with cell communication in a way that promotes wound healing, reduces inflammation and scarring, and aids in cancer therapy. However, the peptide�s half-life in the body is estimated to be less than a day, which is not conducive to long-term treatments. Controlling its release into the body over several weeks can decrease the number of doses required, which is especially useful for glioblastoma treatment. Poly(lactic-co-glycolic acid) (PLGA) is often used for drug encapsulation since it hydrolyzes in the body and is biocompatible. Two methods of αCT1 encapsulation in PLGA were explored. It was found that flash nanoprecipitation increased loading of αCT1 in the particles by 1-2 orders of magnitude compared with the double emulsion method. Particles released αCT1 over three weeks and were non-cytotoxic.
PHD

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10

Datt, Ashish. "Applications of mesoporous silica and zeolites for drug delivery." Diss., University of Iowa, 2012. https://ir.uiowa.edu/etd/3442.

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Zeolites and mesoporous silica were used as drug delivery systems for the loading and release of small drug molecules, aspirin and 5-fluorouracil. Different parameters were varied such as aluminum content in the zeolite, effect of distribution of functional groups and the method of surface modification in case of mesoporous silica. The effect of the aforementioned variables was studied on drug loading and release from these microporous and mesoporous systems. The drug loaded materials were extensively characterized using various physical techniques such as powder X-ray diffraction, nitrogen isotherms, infrared spectroscopy, solid state NMR and thermogravimetric analysis. Quantum calculations and molecular dynamics simulations were performed in order to validate the experimental data and also to obtain a molecular level insight of the drugs inside the pores of the host materials. Drug templated synthesis of mesoporous silica was also carried out in the presence of aspirin as the template. The aspirin templated material was characterized by aforementioned techniques and showed a sustained drug release profile.

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11

Crampton, Hannah Louise. "Synthesis and characterization of melamine-based dendrimers with potential biological applications." Thesis, [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2673.

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12

Prausnitz, Mark R. "Electroporation of tissue and cells for drug delivery applications." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/32647.

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13

Ma, Hui. "Nanomaterials for Biological Applications: Drug Delivery and Bio-sensing." ScholarWorks@UNO, 2013. http://scholarworks.uno.edu/td/1647.

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The idea of utilizing nanomaterials in bio-related applications has been extensively practiced during the recent decades. Magnetic nanoparticles (MPs), especially superparamagnetic iron oxide nanoparticles have been demonstrated as promising candidates for biomedicine. A protective coating process with biocompatible materials is commonly performed on MPs to further enhance their colloidal and chemical stability in the physiological environment. Mesoporous hollow silica is another class of important nanomaterials that are extensively studied in drug delivery area for their ability to carry significant amount of guest molecules and release in a controlled manner. In this study, different synthetic approaches that are able to produce hybrid nanomaterials, constituting both mesoporous hollow silica and magnetite nanoparticles, are described. In a two-step approach, pre-synthesized magnetite nanoparticles are either covalently conjugated to the surface of polystyrene beads and coated with silica or embedded/enclosed in the porous shell during a nanosized CaCO3 templated condensation of silica precursors, followed by acid dissolution to generate the hollow structure. It was demonstrated that the hollow interior is able to load large amount of hydrophobic drugs such as ibuprofen while the mesoporous shell is capable of prolonged drug. In order to simplify the fabrication procedure, a novel in-situ method is developed to coat silica surface with magnetite nanoparticles. By refluxing the iron precursor with mesoporous hollow silica nanospheres in polyamine/polyalcohol mixed media, one is able to directly form a high density layer of magnetite nanoparticles on silica surface during the synthesis, leaving reactive amine groups for further surface functionalization such as fluorescence conjugation. This approach provides a convenient synthesis for silica nanostructures with promising potential for drug delivery and multimodal imaging. In addition to nanoparticles, nanowires also benefit the research and development of instruments in clinical diagnosis. Semiconductive nanowires have demonstrated their advantage in the fabrication of lab-on-a-chip devices to detect many charge carrying molecules such as antibody and DNA. In our study, In2O3 and silicon nanowire based field effect transistors were fabricated through bottom-up and top-down approaches, respectively, for ultrasensitive bio- detection of toxins such as ricin. The specific binding and non-specific interaction of nanowires with antibodies were also investigated.

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Marks, Joyann Audrene. "Synthesis and Applications of Cellulose Derivatives for Drug Delivery." Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/75307.

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In an effort to produce new derivatives of cellulose for drug delivery applications, methods were developed to regioselectively modify C-6 halo cellulose esters to produce cationic derivatives via nucleophilic substitution. Reaction of C-6 substituted bromo and iodo cellulose with trialkylated amines and phosphines produced new cationic ammonium and phosphonium cellulose derivatives which can be explored as delivery agents for nucleic acids, proteins and other anionic drug molecules. It was anticipated that these new derivatives would not only be capable of complexing anionic drug molecules but would have greatly improved aqueous solubility compared to their precursors. The phosphonium derivatives described in this work are an obvious example of such improved solubility properties. Given the importance of cellulose derivatives in making amorphous dispersions with critical drugs, it has also been important to analyze commercially available polymers for the potential impact in oral drug delivery formulations. To do so pairwise blends of cellulosics and synthetic polymers commonly used as excipients were tested for miscibility using techniques such as DSC, mDSC, FTIR and film clarity. Miscible combinations highlight the potential to use combinations of polymers currently available commercially to provide drug delivery solutions for specific drug formulations. The use of melt extrusion in processing some of these drug/polymer dispersions provides a means of highlighting the capability for the use of these cellulosics in melt extruded amorphous dispersions. This solvent free, high pressure method significantly reduces cost and time and can be applied on a large scale. The analysis of long chain cellulose esters and ultimately the novel omega carboxy esters for melt processability significantly impacts the possibilities available for use of those excellent drug delivery agents on a much larger scale.
Ph. D.

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15

Twyman, Lance James. "The synthesis and applications of dentrimeric molecules." Thesis, University of Kent, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259718.

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Chang, Kai. "Structural modification of poly(n-isopropylacrylamide) for drug delivery applications." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/48947.

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Polymeric biomaterials have become ubiquitous in modern medical devices. ‘Smart’ materials, materials that respond to external stimuli, have been of particular interest for biomedical applications such as drug delivery. Poly(n-isopropylacrylamide) (pNIPAAm) is the best studied thermally responsive, biocompatible, ‘smart’ polymer and has been integrated into many potential drug delivery devices; however, the architectural design of the polymer in these devices is often overlooked. My research focus was the exploration of pNIPAAm architecture for biological applications. Two new biomaterials were synthesized as a result. Architectural modification of linear pNIPAAm was used to synthesize a well-defined homopolymer pNIPAAm with a sharp transition slightly above normal body temperature under isotonic conditions. This polymer required a combination of polymerization and control techniques including controlled radical polymerization, hydrogen bond induced tacticity, and end-group manipulation. The synthesis of this polymer opened up a variety of biomedical possibilities, one of which is the use of these polymers in a novel hydrogel system. Through the use of the controlled linear pNIPAAm synthesized through chain architectural modification, hydrogels with physiological transition temperatures were also synthesized. These hydrogels showed greater shrinking properties than traditional hydrogels synthesized in the same manner and showed physiological mechanical properties. Highly branched pNIPAAm was also optimized for biological applications. In this case, the branching reduced the efficacy of end-groups in transition temperature modification but increased the efficacy of certain copolymers. The resulting biomaterial was incorporated into a nanoparticle drug delivery system. By combining gold nanoparticles with highly branched pNIPAAm, which was designed to entrap small molecule drugs, a hybrid system was synthesized where heating of the nanoparticle through surface plasmon resonance can trigger drug release from the pNIPAAm. This system proved to be easy to synthesize, effective in loading, and controlled in release. As shown from the applications, architectural control of pNIPAAm can open up new possibilities with this polymer for biomedical applications. Small structural changes can lead to significant changes in the bulk properties of the polymer and should be considered in future pNIPAAm based medical devices.

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17

De, Cecco Flavia. "Supramolecular polyelectrolyte complexes as mucoadhesive systems for drug delivery applications." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/13393/.

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The aim of this Thesis was the production and the characterization of a mucoadhesive device for drug delivery applications starting from a blend of two polyelectrolytes: polyacrylic acid (PAA) and branched polyethyleneimine (bPEI). Blends at two different compositions of the two polyelectrolytes (90:10 w/w PAA:bPEI and 80:20 w/w PAA:bPEI) were studied. Films and electrospun nanofibrous mats were fabricated and subjected to two different thermal treatments (100°C for 24h and 130°C for 24h) to crosslink the system. Morphological and thermal properties of the obtained devices were investigated through SEM analysis, TGA and DSC analysis, while FT-IR analysis was performed to get insight into the chemical structure of the blend system and the occurrence of crosslinking reaction. Moreover, gel content and swelling degree was evaluated. The mat with 90:10 w/w PAA:bPEI composition, thermally treated for 24 hours at 130°C was identified as the best system for drug delivery applications. In fact, a good crosslinking degree was achieved in the system (a gel content value of 96% was obtained) that allowed to maintain a good fiber morphology after immersion in water for 24h. This mat was therefore loaded with a 10% w/w of Econazole Nitrate, an antimicotic drug, and subjected to entrapping efficiency tests through HPLC, to investigate how efficiently the drug was loaded in the mat. Results showed that 93% of the initial weight of Econazole Nitrate added in the blend solution was loaded in the fibres. The characterization performed demonstrated that the produced device had suitable properties to work as a drug delivery system.

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Bergstrand, Nill. "Liposomes for Drug Delivery : from Physico-chemical Studies to Applications." Doctoral thesis, Uppsala University, Department of Physical Chemistry, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3390.

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Physico-chemical characterisation of structure and stability of liposomes intended for drug delivery is the central issue in this thesis. In addition, targeted liposomes to be used in boron neutron capture therapy (BNCT) were developed.

Lysolipids and fatty acids are products formed upon hydrolysis of PC-lipids. The aggregate structure formed upon mixing lysolipids, fatty acids and EPC were characterised by means of cryo-TEM. A relatively monodisperse population of unilamellar liposomes was detected in mixtures containing equimolar concentration of the three components.

The interactions between alternative steric stabilisers (PEO-PPO-PEO copolymers) and conventional PC-and pH-sensitive PE-liposomes were investigated. Whereas the PE-liposomes could be stabilised by the PEO-PPO-PEO copolymers, the PC-liposomes showed an enhanced permeability concomitant with the PEO-PPO-PEO adsorption.

Permeability effects induced by different PEG-stabilisers on EPC liposomes were shown to be dependent on the length of the PEG chain but also on the linkage used to connect the PEG polymer with the hydrophobic membrane anchor.

An efficient drug delivery requires, in most cases, an accumulation of the drug in the cell cytoplasm. The mechanism behind cytosolic drug delivery from pH-sensitive liposomes was investigated. The results suggest that a destabilisation of the endosome membrane, due to an incorporation of non-lamellar forming lipids, may allow the drug to be released.

Furthermore, sterically stabilised liposomes intended for targeted BNCT have been characterised and optimised concerning loading and retention of boronated drugs.

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19

Fach, Lars Matthias [Verfasser]. "Protein-based nanoparticles for drug delivery applications / Lars Matthias Fach." Mainz : Universitätsbibliothek Mainz, 2018. http://d-nb.info/116056146X/34.

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Chowdhury, D. F. "Development of artificial carbon nanotube vesicles for drug delivery applications." Thesis, University of Oxford, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.543555.

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Davidson, Scott. "Bio-inspired silica : development for drug delivery applications and biocompatibility." Thesis, University of Strathclyde, 2016. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=27559.

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The development of a drug delivery system (DDS) is essential to remedy the limitations of free drug molecules. The use of silica as a DDS over other systems (for example, liposomes) can be attributed to it being more robust and versatile. This thesis investigates bio-inspired silica (BIS) and compares it to mesoporous silica nanoparticles (MSN), which have received much attention for drug delivery applications. The BIS synthesis utilised amines to condense silica quicker than MSN, under benign conditions and without the use of hazardous chemicals. With this synthesis method drugs can be loaded in situ and there is potential for amines to have dual function of condensing silica and acting as functionalisation. BIS has also been shown to be more biocompatible than MSN. Due to these reasons it can be argued that BIS has the potential to be a more desirable silica DDS than MSN.Using ibuprofen as a model drug, reaction conditions (e.g. choice of amine additive, synthesis pH and maturation time) were systematically investigated to elucidate their effects upon drug loading and release. BIS synthesised with the amine poly(allylamine hydrochloride) (PAH) (which will henceforth referred to as BIS-PAH) was focused on, as this was the only amine system which released a significant proportion of loaded drug and achieved comparable or improved ibuprofen loading when compared to MCM-41. PAH plays an important role in facilitating the loading of ibuprofen, however if too much is present, release is inhibited greatly. The condensation rate of silica is also an important factor; when condensation rate was increased more drug was able to be released. This is likely due to less of the drug being entrapped within the silica particle and more being phys-adsorbed to the silica surface. Next the use of BIS to deliver hydrocortisone (HC) was investigated. Current treatments for adrenocorticoid insufficiency using hydrocortisone do no mimic the natural circadian variation in levels of blood cortisol. Firstly, the stability of HC during the in situ loading process was measured and data are presented that show that HC must be loaded post-synthesis, to avoid degradation in the reaction mixture. The efficiency of loading was largely unaffected by amine, however, only BIS-PAH allowed for drug release. Longer BIS-PAH maturation times gave lowered loading but the release was improved. Finally, biocompatibility of BIS was also investigated and it was found that, BIS was able to pass through the gut wall into the blood stream, and it was non-haemolytic when compared to MCM-41. There is a potential for bioaccumulation due to silica’s chemical stability. Although the use of BIS for delivery of hydrocortisone was unsuccessful, BIS does have several advantages over MCM-41 (such as quicker synthesis route, involving a one-pot synthesis and drug loading method, simple controllability, lack of hazardous chemicals and superior biocompatibility) and the results presented here show that BIS has similar or improved drug loading and release profiles to MCM-41 when using ibuprofen. With further drug and biocompatibility experiments, these benefits give BIS real potential as a viable DDS to be further investigated.

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Deshmukh, Ameya. "MMP-Degradable Biosensors: Applications in Drug Delivery and Personalized Medicine." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1585925271421393.

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Rodriguez, Lidia Betsabe. "Controlled Release System for Localized and Sustained Drug Delivery Applications." University of Toledo / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1365107103.

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Mehta, Ankit N. "Tampon-like Foam Structures for Bioresponsive Vaginal Drug Delivery Applications." University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1396522494.

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Yan, Huan. "MICRO- AND NANO-MATERIALS FOR DRUG DELIVERY AND BIOIMAGING APPLICATIONS." Kent State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=kent1428155172.

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Kakde, Deepak. "Synthesis, characterisation and applications of new polyesters for drug delivery." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/37381/.

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In recent years, a number of reports have focused on the use of polyesters in drug delivery due to their intrinsic biocompatibility and biodegradability. In this thesis, aliphatic polyesters were synthesized by polycondensation reaction and ring opening polymerization reactions. The properties of the polymers and drug delivery potential of the resultant materials were evaluated. In the polycondensation reactions, a series of aliphatic polyesters of similar molecular weight were synthesized by reacting 1,10-decanediol with different ratios of succinic acid/phenylsuccinic acid and the effects of phenyl group side-chain substitution on polymer properties was investigated. A solvent-free melt polycondensation method using scandium (III) triflate as catalyst at an industrially relevant temperature (120 °C) was used. As the phenyl content increased, the polymers changed from semicrystalline to amorphous in state. The loading capability of polymers was checked by formulating nanoparticles containing coumarin 6 as a fluorescent dye analogue of active drugs. A polymer with a 70/30 ratio of succinic acid and phenylsuccinic acid showed the highest dye loading among the set of materials synthesised. This polymer was found to be degradable over time under selected experimental conditions. Amphiphilic block co-polymers from the PluronicTM class were used to stabilize, in PBS, nanoparticles formed from these polyesters by nanoprecipitation routes. The metabolic activity, cell membrane integrity and lysosomal functions of C3A cells dosed with the polymers were determined to observe the cytocompatibility of the highest dye-loaded nanoparticles. Activity relative to undosed C3A cells was retained at more than 80% in the all of the assays. Imaging of Pluronic coated and uncoated nanoparticles in C3A cells suggested that both types of the nanoparticles were endocytosed in the early stage of the study (within 10 min). The internalization of nanoparticles was increased progressively over the study time. These results indicated the possible utility of the selected polymers in diagnostic and delivery applications. Ring opening polymerization (ROP) reactions were used for the synthesis of a diblock (mPEG-b-PεDL) and a triblock (PεDL-b-PEG-b-PεDL) copolymer from a seven membered ε-decalactone (ε-DL) monomer obtained from renewable sources. A diblock (mPEG-b-PεDL) copolymer was compared with structurally similar mPEG-b-PCL copolymer synthesized via ROP of ε-caprolactone (ε-CL) monomer, which can be considered as a non-renewable monomer. A six membered δ-decalactone (δ-DL) was also used for the synthesis of a diblock copolymer (mPEG-b-PδDL) to compare the reaction kinetics and properties of the copolymers. The copolymers were prepared via bulk polymerisation using 1,5,7-Triazabicyclo[4.4.0]dec-5-ene (TBD) as a metal-free catalyst to replace the conventionally used stannous octoate [Sn(Oct)2]. A higher polymerization efficiency was achived with TBD compared to Sn(Oct)2 catalyst. However, a notable difference in the reaction temperature required for ε-DL and δ-DL polymerization was observed. The comparison with a structural analogue, i.e. ε-CL, demonstrated that the ε-DL polymerization was inhibited due to the presence of the alkyl chain of ε-DL monomer. However, a higher reaction time (12 h for TBD and 24 h for Sn(Oct)2) in CROP of ε-DL was addressed by using microwave based ring opening polymerization (MROP) reaction. The MROP was adopted as a ‘green’ and cheap heating method alternative to conventional heating (CROP) for the synthesis of mPEG-b-PεDL diblock copolymers using TBD as a catalyst. All the reactions were conducted in bulk. The MROP was designed based on the dielectric properties of all the reacting materials, as it was found that ε-DL monomers showed good absorption of MW radiation (tanδ>0.5). Accordingly, MROP resulted in a higher rate of ε-DL polymerization compared to CROP but comparison of the synthesis of mPEG-b-PCL copolymer by MROP indicated that the presence of the alkyl chain in ε-DL monomer significantly reduced the rate of polymerization. The synthesized mPEG-b-PεDL copolymer was investigated as a potential drug delivery vehicle for solubilization and controlled delivery of indomethacin. The indomethacin loading and release from mPEG-b-PεDL micelles (amorphous core) was compared against well-established mPEG-b-PCL micelles (semicrystalline core). The drug-polymer compatibility was also determined through a predictive computational approach to access the drug solubilisation (or drug loading) into hydrated micelles. The micelles were prepared by solvent evaporation method and characterized for size, morphology, indomethacin (IND) loading and release. Both of the micelle formulations showed a uniform distribution of spherical micelles with size <60 nm. However, a significantly higher size of empty mPEG-b- PεDL micelle was observed compared to mPEG-b-PCL micelles. A higher compatibility of the drug was predicted with PCL core as determined by modified Flory-Huggins interaction parameters (sp) using the Hanson solubility parameter (HSP) approach. The compatibility of the drug was determined for both of the segments (hydrophilic and hydrophobic) of the copolymers and found to be in the order of sp (PεDL)> sp (mPEG)> sp (PCL). The predictions suggested that more IND should encapsulate within the micelles with PCL core compared to PDL core, but the IND loading experiments revealed an overall higher loading in PεDL core (6.55 wt%) compared to PCL core (5.39 wt%) (P < 0.05, unpaired student’s t-test). However, consideration of the IND loading per unit volume of the micelles revealed that the PCL cored micelles was able to load 1.5 times more compared to the PεDL cored micelles. This result illustrated the higher compatibility of the IND with PCL core in accordance with the solubility parameter calculations. These data also suggested that the overall higher IND loading in PεDL core was attributable to the amorphous nature of the core which increased the core volume by 1.81 times compared to the PCL core. Drug release studies showed the sustained release pattern from both of the micelle systems although the semicrystalline PCL core (80% drug release in 110 h) was able to release the drug for a longer period compared to PεDL core (80% drug release in 72 h). Cell viability tests demonstrated the cytocompatibility of the mPEG-b-PεDL polymer. The micelles were internalized effectively in the early stages of the study and progressively increased with time. The results of the present thesis suggested that novel aliphatic polyester can be good candidates for the drug delivery applications and further studies can explore the possible applications of these polymers in the biomedical field.

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27

Steiert, Elena [Verfasser]. "Dynamic Protein-based Nanoparticles for Drug Delivery Applications / Elena Steiert." Mainz : Universitätsbibliothek Mainz, 2020. http://d-nb.info/1205821899/34.

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Lee, Ryan Thomas. "Modulation of Keratin Biomaterial Formulations for Controlled Mechanical Properties, Drug Delivery, and Cell Delivery Applications." Miami University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=miami1385549579.

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Hilder, Tamsyn A. "Modelling nanostructures as nano-oscillators for applications in nanomedicine." Access electronically, 2008. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20080918.101103/index.html.

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30

Mazumder, Sonal. "Synthesis and Characterization of Drug-Containing, Polysaccharide-Based Nanoparticles for Applications in Oral Drug Delivery." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/23692.

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Amorphous solid dispersions of polysaccharide-drug nanoparticles were produced by a rapid precipitation process known as flash nanoprecipitation and the formulation process and properties of nanoparticles were investigated. In this thesis, several novel cellulose derivatives and a pullulan derivative were studied. Among these polymers, carboxymethyl cellulose acetate butyrate (CMCAB)-drug nanoparticles were investigated in detail. Previous work has shown that the presence of different chemical groups in CMCAB could aid in complexation with hydrophobic drugs with low solubility, forming an amorphous matrix which can increase the effective solubility and, hence, bioavailability of the drug in physiological conditions. An antibacterial drug and two less soluble anti-viral drugs were selected as model drugs for this study. A separate study was conducted with several other cellulose derivatives like cellulose acetate propionate adipates with two different degree of substitution 0.33 and 0.85 (CAP-Adp 0.33 and CAP-Adp 0.85), cellulose acetate sebacate (CA-320S Se) and butyl pullulan-6-carboxylate (BPC) polymers. The effect of polymer interaction with drug molecule on release of antiviral drugs was studied with these latter polymers.
The purpose of this research was two-fold. First, the methodology for producing drug-polymer nanoparticles with well-defined particle size distributions was developed. Second, the factors affecting drug loading and release properties of these nanoparticles were investigated. The nanoparticles were processed using two methods of solvent removal and drying to investigate their effects on drug loading and particle size: (a) various combinations of rotary vacuum evaporation (rotavap) and acid-induced flocculation were used and (b), dialysis followed by freeze drying. Dynamic light scattering showed particle sizes were between 150-400 nm with polydispersity index values as low as 0.12. The antibiotic drug loading efficiencies ranged from 14-40%, whereas drug loading efficiency as high as 85 % was attained with the antiviral drug. The dissolution studies showed an increase in the solution concentration and release of the amorphous drug nanoparticles. The high glass transition temperature helped to stabilize the drug in an amorphous form, thus increasing the effective solution concentration of the drug in an aqueous medium.

Ph. D.

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31

Cheung, Wai-Han. "Novel steroidal metal complexes with potential pharmaceutical applications." Thesis, Loughborough University, 1992. https://dspace.lboro.ac.uk/2134/27879.

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A study to develop novel lipophilic metal ion complexes based on dihydrocholesterol was undertaken. Steroid ligands functionalised at the 2- and 3- positions were synthesized as possible bidentate ligands for complexation of metal ions. Condensation of 5α-cholestan-3-one with ethyl formate in the presence of base gave 2-hydroxymethylene-5α-cholestan-3-one, and 2- acetyl-5α-cholestan-3-one was obtained by the reaction between 3- trimethylsilyloxy-5α-cholest-2-ene and acetyl chloride. Attempts to synthesize 2,3-dioximino-5α-cholestane from 5α-cholestan-3-one and 2α-hydroxy-5α-cholestan-3-one were unsuccessful. Likewise 2- methylene-5α-cholestan-3-one, which was expected to lead to other bidentate ligands, could not be prepared satisfactorily from 5α-cholestan- 3-one or 3-trimethylsilyloxy-5α-cholest-2-ene.

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32

Leonard, Alex. "Elastin Like Polypeptides as Drug Delivery Vehicles in Regenerative Medicine Applications." Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/5981.

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Elastin like polypeptides (ELPs) are a class of naturally derived biomaterials that are non-immunogenic, genetically encodable, and biocompatible making them ideal for a variety of biomedical applications, ranging from drug delivery to tissue engineering. Also, ELPs undergo temperature-mediated inverse phase transitioning, which allows them to be purified in a relatively simple manner from bacterial expression hosts. Being able to genetically encode ELPs allows for the incorporation of bioactive peptides and functionalization of ELPs. This work utilizes ELPs for regenerative medicine and drug delivery. The goal of the first study was to synthesize a biologically active epidermal growth factor-ELP (EGF-ELP) fusion protein that could aid in the treatment of chronic wounds. EGF plays a crucial role in wound healing by inducing epithelial cell proliferation and migration, and fibroblast proliferation. The use of exogenous EGF has seen success in the treatment of acute wounds, but has seen relatively minimal success in chronic wounds because the method of delivery does not protect exogenous EGF from degradation, or prevent it from diffusing away from the application site. We created an EGF-ELP fusion protein to combat these issues. As demonstrated through the proliferation of human skin fibroblasts in vitro, the EGF-ELP may be able to aid in the treatment of chronic wounds. Furthermore, the ability of the EGF-ELP to self-assemble near physiological temperatures could allow for the formation of drug depots at the wound site and minimize diffusion, increasing the bioavailability of EGF and enhancing tissue regeneration. The objective of the second study was to create an injectable hydrogel platform that does not require conjugation of functional moieties for crosslinking or biological activity. Hydrogels are three-dimensional polymer networks that are able to absorb water and biological fluids without dissolving. Their high water content gives them physical properties similar to soft tissues, making them useful as scaffolds for cell migration and drug delivery vehicles. Injectable hydrogels that crosslink in situ are particularly useful because they can form to the shape of the defect, providing a near perfect fit. However, many hydrogel platforms cannot be crosslinked in situ because cytotoxic crosslinking reagents are required. Additionally, hydrogels typically require the chemical conjugation of crosslinking domains and bioactive peptides to the polymer backbone, adding more steps and time required for hydrogel production. We devised an injectable hydrogel platform that can be synthesized in a single step using photoreactive ELPs as the polymer backbone. Leucine auxotrophic Eshcherichia coli expressed ELPs containing photoleucine, a leucine analog and photoreactive diazirine crosslinker, which is substituted for leucine periodically throughout the ELP sequence. Upon exposure to ultraviolet radiation (~370 nm), photoleucine is able to form covalent crosslinks with amino acid side chains, forming a polymer network for hydrogel formation. Additionally, recombinant growth factors and morphogens can be encoded into the ELP sequence providing a simple method of hydrogel functionalization for regenerative medicine applications. The potential for this platform was demonstrated through in vivo crosslinking of photoreactive ELPs in the expression hosts. Though the production of the photoreactive ELP was not as forthright as originally assumed. The substitution of noncanonical amino acids typically requires the auxotrophic expression hosts to be starved of the amino acid that they are auxotrophic for. A noncanonical analog of said amino acid can then be supplemented into expression media, maximizing incorporation. In this investigation, it was found the addition of photoleucine alone inhibited photoreactive ELP expression. ELP expression only occurred in the presence of photoleucine if valine or leucine was also present in the media. Furthermore, valine was found to aid the production of ELPs as much as leucine. It was postulated the bacterial translational machinery might need to be altered for optimal ELP expression.

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Kulkarni, Harsha Prabhakar Wu Yue. "Synthesis and applications of titania nanotubes drug delivery and ionomer composites /." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2008. http://dc.lib.unc.edu/u?/etd,1649.

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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2008.
Title from electronic title page (viewed Sep. 16, 2008). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Curriculum in Applied and Materials Sciences." Discipline: Applied and Materials Sciences; Department/School: Applied and Materials Sciences.

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Konhäuser, Matthias [Verfasser]. "Dynamic Polysaccharide-based Nanoparticles for Advanced Drug Delivery Applications / Matthias Konhäuser." Mainz : Universitätsbibliothek Mainz, 2020. http://d-nb.info/1202851681/34.

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35

Williamson, Matthew R. "Novel biodegradable fibres for applications in tissue engineering and drug delivery." Thesis, Aston University, 2003. http://publications.aston.ac.uk/11000/.

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The preparation and characterisation of novel biodegradable polymer fibres for application in tissue engineering and drug delivery are reported. Poly(e-caprolactone) (PCL) fibres were produced by wet spinning from solutions in acetone under low shear (gravity flow) conditions. The tensile strength and stiffness of as-spun fibres were highly dependent on the concentration of the spinning solution. Use of a 6% w/v solution resulted in fibres having strength and stiffness of 1.8 MPa and 0.01 GPa respectively, whereas these values increased to 9.9 MPa and 0.1 GPa when fibres were produced from 20% w/v solutions. Cold drawing to an extension of 500% resulted in further increases in fibre strength (up to 50 MPa) and stiffness (0.3 GPa). Hot drawing to 500% further increased the fibre strength (up to 81 MPa) and stiffness (0.5 GPa). The surface morphology of as-spun fibres was modified, to yield a directional grooved pattern by drying in contact with a mandrel having a machined topography characterised by a peak-peak separation of 91 mm and a peak height of 30 mm. Differential scanning calorimetery (DSC) analysis of as-spun fibres revealed the characteristic melting point of PCL at around 58°C and a % crystallinity of approximately 60%. The biocompatibility of as-spun fibres was assessed using cell culture. The number of attached 3T3 Swiss mouse fibroblasts, C2C12 mouse myoblasts and human umbilical vein endothelial cells (HUVECs) on as-spun, 500% cold drawn, and gelatin coated PCL fibres were observed. The results showed that the fibres promoted cell proliferation for 9 days in cell culture and was slightly lower than on tissue culture plastic. The morphology of all cell lines was assessed on the various PCL fibres using scanning electron microscopy. The cell function of HUVECs growing on the as-spun PCL fibres was evaluated.

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Angelos, Sarah Ann. "Molecular machines supported on mesoporous silica nanoparticles for drug delivery applications." Diss., Restricted to subscribing institutions, 2009. http://proquest.umi.com/pqdweb?did=1835827851&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.

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37

Mäe, Maarja. "Rational modifications of cell-penetrating peptides for drug delivery : Applications in tumor targeting and oligonucleotide delivery." Doctoral thesis, Stockholms universitet, Institutionen för neurokemi, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-8374.

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High molecular weight biomolecules are becoming important in the development of new therapeutics. However, their size and nature creates a major limitation for their application – poor penetration through biological membranes. A new class of peptides, cell-penetrating peptides (CPPs), has shown the capability to transport various macromolecules inside the cells. However, there are at least two limiting factors for successful application of CPPs: the lack of cell-type specificity and restricted bioavailability resulting from endocytic uptake of CPPs and entrapment in endosomal compartments. This thesis aims at designing delivery vehicles for therapeutic substances. In papers I-III, the CPPs have been rationally modified in order to achieve in vivo selectivity towards cancer cells. The first two papers employ tumor homing peptides as targeting moieties coupled to the N-termini of CPPs. In the third paper, a CPP is C-terminally prolonged with a matrix metalloproteinase 2 (MMP-2) specific cleavage site followed by an inactivating amino acid sequence. In tissues overexpressing MMP-2, i. e. in proximity to cancer, the CPP is activated after proteolytic removal of the inactivating sequence, thus the cargo can be transported inside the cells. In paper IV, several CPPs have been N-terminally modified with a stearyl moiety and applied for the delivery of splice-correcting oligonucleotides. We show that stearyl-TP10 is as effective in oligonucleotide delivery as Lipofectamine™ 2000. Moreover, stearyl-TP10 has preserved efficacy in serum and is not toxic to cells. In conclusion, the rational modifications of CPPs greatly potentiate their application in cargo delivery both in vitro and in vivo.

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38

Lin, Wan-Hua. "Cellulose Aerogel Monoliths and Microparticles and Their Applications in Drug Delivery System." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1515433467041194.

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39

Choi, Sungmoon. "Fluorescent noble metal nanodots for biological applications." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37195.

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Commercial organic dyes are widely used for cellular staining due to their small size, high brightness, and chemical functionality. However, their blinking and photobleaching are not ideal for studying dynamics inside live cells. An improvement over organics and much larger quantum dots, silver nanodots (Ag NDs) exhibit low cytotoxicity and excellent brightness and photostability, while retaining small size. We have utilized ssDNA hairpin structures to encapsulate Ag NDs with excellent spectral purity, high concentration, and good chemical and photophysical stability in a variety of biological media. Multi-color staining of fixed and live cells has been achieved, suggesting the promise of Ag NDs as good fluorophores for intracellular imaging. The great brightness and photostability of Ag nanodots indicate that they might be outstanding imaging agents for in vivo studies when encapsulated in delivery vehicles. In addition, Ag NDs can be optically modulated, resulting in increased sensitivity within high backgrounds. These good characteristics are combined with delivery vehicles such as PLGA and nanogels. After encapsulation, Ag nanodots still retain their good photophysical properties and modulation. It might be useful for in vivo applications in the near future

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40

Helfrich, Marcus Robert. "Preliminary investigations into the development of novel layered phosphonic acid vesicles for targeted drug delivery applications /." view abstract or download file of text, 2002. http://wwwlib.umi.com/cr/uoregon/fullcit?p3045088.

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Thesis (Ph. D.)--University of Oregon, 2002.
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 184-193). Also available for download via the World Wide Web; free to University of Oregon users. Address: http://wwwlib.umi.com/cr/uoregon/fullcit?p3045088.

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Engstrand, Johanna. "Designing star-like block-copolymers as compartmentalized nanostructures for drug delivery applications." Thesis, Uppsala University, Department of Materials Chemistry, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-119971.

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This thesis describes syntheses and characterization of star-like amphiphilic block copolymers consisting of poly(ethylene glycol) (PEG) as the hydrophilic block,polycarbonate as the hydrophobic block and an amine-containing dendrimer as the core molecule. The macromolecules were synthesized by either a convergent or adivergent approach that includes tandem click reactions and ring opening polymerizations (ROP) of methyl trimethyl carbonates (MTC) with differentfunctionalities. The ROP of MTC monomers was performed using organocatalysts that allow mild reaction condition and reasonable molecular weight distribution(PDI~1.3). These synthetic approaches provide the resultant polymers with three different conformations, which are; mikto-arm type, comb-block with short PEGbrushes, and linear block with long PEG chain. The star-like polymers that were synthesized were all water soluble and most of them formed nano aggregates inwater. Different morphologies were observed in AFM study depending on the polymer conformation. Interestingly, some of them had indications pointing towards alower critical solution temperature.

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42

Perelman, Loren Avery. "Macromolecular coatings on porous silicon applications in drug delivery, biosensing, and composites /." Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2008. http://wwwlib.umi.com/cr/ucsd/fullcit?p3290779.

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Thesis (Ph. D.)--University of California, San Diego, 2008.
Title from first page of PDF file (viewed February 5, 2008). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references.

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43

Argyo, Christian. "Tailoring properties of multifunctional Mesoporous Silica nanoparticles for controlled drug delivery applications." Diss., Ludwig-Maximilians-Universität München, 2014. http://nbn-resolving.de/urn:nbn:de:bvb:19-183268.

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44

Hasan, Mohammad Nazmul. "Developing Glycopeptide based nanocarriers by ring opening polymerization for drug delivery applications." Thesis, Uppsala universitet, Institutionen för kemi - Ångström, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-233891.

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Synthetic glycopeptides have attracted much interest in the biomedical field due to their structural similarities to the natural glycopeptides or glycoproteins. It is still difficult to synthesize glycopeptides with greater efficiency and ring opening polymerization remains an effective way to do so. Proteoglycans are a special class of glycoproteins with glycosaminoglycan chains. In this study, I tried to do controlled ring opening polymerization of Hyaluronic acid derivatives with smaller to higher molecular weight while avoiding side reactions. It is challenging to work with higher molecular weight molecules and do a click reaction in water effectively. Making nanopolymers with a desired size, studies of the characteristics, and how to build nanocarriers for drug delivery application was the focus of this work. Polymeric characteristics, e.g., modification and polymer formation were studied by nuclear magnetic resonance technique; Particle size was studied by dynamic light scattering and the loading of rhodamine B encapsulated into the polymer was measured by confocal imaging technique.

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45

Madeira, do Ó. João. "Applications of glycopolymer libraries as protein aggregation modulators and drug delivery systems." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/38014/.

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The biopharmaceutical market has been on the rise for the past two decades and is expected to continue to excel, currently presenting a growing rate of more than double than conventional pharma. Traditionally this growth has been hindered by multiple formulation issues such as poor bioavailability and poor stability. Consequently, the drive to optimise the stability of protein drug candidates via formulation impels the need for development of novel excipients. Novel glycopolymer excipients were reported to confer improved protein stability in selected cases. Nonetheless,their structure-function relationship and wider applicability remain largely unknown. Here we report the synthesis of glycopolymers with different molecular architectures based on mannose, galactose, arabinose, N-acetyl glucosamine, lactose and trehalose, and nvestigate their utility as excipients for the solution formulation of a monoclonal antibody (mAb). In this thesis work the physical stability of selected antibodies was measured as the unfolding transition temperature (Tm) and aggregation onset temperature (Tagg), as a function of glycopolymer properties, such as the nature of sugar repeating unit, macromolecular architecture and concentration. Results show that, in contrast to the stabilising effect of the corresponding mono- and di-saccharide constituents, both linear and 4-arm star glycopolymers generally destabilised the antibody, decreasing both Tm and Tagg. Accelerated stability studies of a concentrated mAb solution followed the same trend, where an increasing glycopolymer:mAb molar ratio generally decreased the percentage monomer(i.e. increased soluble aggregates). Importantly, trehalose-based glycopolymers further generated visible aggregates that could not be predicted from Tm or Tagg data. The data demonstrate a complex interplay of sugar chemistry and solution concentration of synthetic glycopolymers on their modulation of protein conformational stability and aggregation propensity. The mechanisms involved in protein:glycopolymer interaction, both in solution and dry state were further investigated, thus unravelling the behaviour reported in terms of protein stabilisation. Finally, the glycopolymers were studied as drug delivery systems, acting as solubility enhancers for hydrophobic species in aqueous solutions, through the use of extrinsic fluorescent dyes.

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46

Edward, Jonathan M. (Jonathan Mark). "Commercial potential for thermal & magnetic sensitive polymer in drug delivery applications." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/45958.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2008.
Includes bibliographical references (leaves 75-80).
Thermal and magnetically sensitive polymers are a new class of materials with unique properties suitable for applications in drug delivery. Specifically, these polymers can be combined with a drug reservoir to make a drug delivery device that can be triggered externally. Such a device could be implanted subcutaneously and allow for temporal control of drug release and localized delivery. Current experiments have shown that a prototype device is capable of delivering both small and large molecule drugs. Attractive medical applications for this technology were discovered and their respective markets examined. Additionally, the scientific literature and intellectual property in this field were analyzed for competing technologies that would hinder development of this invention. Novel attributes of this technology were also identified and specific competitive advantages made evident. To facilitate the commercialization of this novel technology, a business model has been proposed that identifies possible risks and provides strategies for overcoming them. Using this model, a timeline for future research and development has been constructed that traces the technology from its current state to a final product that can be launched commercially. The requirements for regulatory approval have also been investigated and a plausible manufacturing process has been established. Furthermore, a cost model and pricing analysis has been conducted to determine if a viable business proposition around this technology can be made.
by Jonathan M. Edward.
M.Eng.

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47

Helm, Eric. "Solute Partitioning in Elastin-like Polypeptides: A Foundation for Drug Delivery Applications." Cleveland State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=csu1450790146.

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48

Wen, Amy M. "Engineering Virus-Based Nanoparticles for Applications in Drug Delivery, Imaging, and Biotechnology." Case Western Reserve University School of Graduate Studies / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=case1452954511.

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49

Fenn, Spencer Lincoln. "Seaweed to Sealant : Multifunctional Polysaccharides for Regenerative Medicine and Drug Delivery Applications." ScholarWorks @ UVM, 2017. http://scholarworks.uvm.edu/graddis/697.

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Pneumothorax, or a collapsed lung, is a serious medical condition resulting when air or fluid escapes the lung into the chest cavity and prevents the lung from inflating. Few viable means of sealing the damaged and leaking tissues are currently available, leading to longer hospital stays, multiple interventions, and increasing costs of care. The motivation of this dissertation is to engineer a novel polysaccharide-based therapeutic surgical sealant, which can be utilized to seal trauma-induced damage to the outer lining of the lung, i.e. pleura, preventing or reversing lung collapse to restore normal breathing function. The use of polysaccharides, such as alginate and hyaluronan, has become increasingly prevalent in biomedical and tissue engineering applications due to the ability to add functionality through chemical modification, allowing for tunable mechanical and physical properties. These hydrophilic polymer chains can be crosslinked to form hydrogels, which can retain large volumes of water and can mimic the properties of tissues found within the body. In this work, polysaccharide hydrogel sealants were engineered with well-regulated gelation and mechanical properties, and further modified to achieve adhesion to biological tissues. This was accomplished by mimicking the mechanical and physical properties of the complex tissues, and crosslinking the hydrogels in situ using a visible light-initiated system. Methacrylated alginate and oxidized alginate were successfully synthesized and utilized to fabricate adhesive sealant patches, which can adhere and seal damaged tissues in vivo. Methacrylation was implemented to allow covalent photo-crosslinking between adjacent polymer chains in solution. Here, a novel anhydrous chemistry was developed to allow for precise control over the degree of methacrylation and thus tune the mechanical properties of the resulting hydrogels by modulating the number of crosslinkable side-groups attached to the polysaccharide chain. To increase the adhesive properties of the resulting hydrogels, oxidation of the polysaccharide chain was subsequently implemented to form functional aldehyde groups capable of protein interactions through the formation of imine bonds on biological tissue surfaces. To test the performance of this multifunctional material, burst pressure testing was executed, revealing the relationship between the two distinct chemical modifications performed and the mechanical and adhesive properties of the resulting sealant. In addition, methacrylated alginate was utilized to synthesize therapeutic, drug-encapsulating hydrogel nanoparticles, which when incorporated within the polysaccharide-based surgical sealant allow for local drug release. The ability to control drug release at the site of application further broadens the potential uses of this surgical sealant patch and will be discussed further within this dissertation.

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Fan, Dongmei. "Mesoporous silicon/biopolymer composities for orthopedic tissue engineering and drug delivery applications." [Fort Worth, Tex.] : Texas Christian University, 2008. http://etd.tcu.edu/etdfiles/available/etd-12192008-090502/unrestricted/fan.pdf.

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Dissertations / Theses on the topic 'Drug Delivery Applications'

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