Journal articles: 'Nanoparticels'

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Yang, Chun, Feng Yan Ge, Jin Cai Li, Zai Sheng Cai, and Fang Fang Qin. "Silver Nanoparticles with Enhanced Fluorescence Effects on Fluorescein Derivative." Advanced Materials Research 602-604 (December 2012): 187–91. http://dx.doi.org/10.4028/www.scientific.net/amr.602-604.187.

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Silver nanoparticles were prepared by sodium borohydride reduction method for analyzing metal-enhanced fluorescence property. Some variables including the dosage of reagent, reacting temperature and pH value had been investigated. Subsequently, a comparison of metal-enhanced fluorescence efficiency was made between two kinds of fluorescent dyes, namely fluorescein and 6-carboxyfluorescein at different silver concentrations. The experimental results show that the fluorescence of both dyes are remarkably enhanced. It is interesting to note that the increase of emission intensity is stronger than that of their corresponding excitation ones. Furthermore, a 5.038-fold increase in fluorescence for 6-carboxyfluorescein while a 2.506-fold increase for fluorescein are observed. This may attribute to the interaction between dyes and silver nanoparticels.

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Trzaskus, K. W., A. J. B. Kemperman, and D. C. Nijmeijer. "Fouling Behavior of Silver Nanoparticels During Membrane Filtration." Procedia Engineering 44 (2012): 2096–97. http://dx.doi.org/10.1016/j.proeng.2012.09.058.

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Shan, Feng, and Tong Zhang. "Shape and Size Dependent Light Absorption Enhancement of Silver Nanostructures in Organic Solar Cells." Solid State Phenomena 266 (October 2017): 90–94. http://dx.doi.org/10.4028/www.scientific.net/ssp.266.90.

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Metal nanoparticles (MNPs) induced light absorption enhancement using for the improvement of power conversion efficiency of organic solar cells (OSCs) is a new research direction in photovoltaics. However, the device performance influence of the shape and size of MNPs has not been well investigated. In this paper, we focused on the comparison study of the optical absorption enhancement between silver nanospheres (Ag-NSs) and silver nanocubes (Ag-NCs) which are embedded in the active layer of OSCs using finite element method (FEM) simulation. Influence of the structural parameters, including the size and shape of nanoparticels, and their relative distance are systematically discussed. The results indicated that the light absorption enhancement employing Ag-NCs is much higher than that of Ag-NSs in the 300–800 nm wavelength range. Meantime, once the distance between the adjacent nanoparticles is well controlled, the optimal absorption enhancement factor of OSCs can be obtained. As the scattering cross-section of Ag-NCs is much higher than that of Ag-NSs over a broad wavelength range, the optimized light enhancement of Ag-NCs reaches 19 % which is 1.26 times higher than that of Ag-NSs.

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Kilic, Mehmet Emin, and Sakir Erkoc. "Structural Properties of ZnO Nanoparticels and Nanorings: Molecular Dynamics Simulations." Journal of Computational and Theoretical Nanoscience 10, no. 6 (June 1, 2013): 1490–96. http://dx.doi.org/10.1166/jctn.2013.2878.

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Ruan, Li Li, Da Xin Wang, You Wei Zhang, Jiong Xin Zhao, Min Wu Wang, Xiu Fang Zhang, and Nan Liang Chen. "Study on Preparation and Property of Drug Loading of AZM-PCL Nanoparticels." Applied Mechanics and Materials 121-126 (October 2011): 1764–68. http://dx.doi.org/10.4028/www.scientific.net/amm.121-126.1764.

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This study was to prepare polycaprolactone (PCL) nanoparticles. The biodegradable PCL was used as the carrier, and Azithromycin (AZM) was used as the model drug. AZM-PCL nanoparticles (AZM-PCL-NPS) were prepared by desolvation method. The effect of preparation condition: concentration of PCL, molecular weight of PCL, organic solvents, dosage ratio and so on, were specially noted and compared. A homogeneous size distribution and good dispersion were observed, the average diameter was around 70~400 nm, and the distribution index was 0.036~0.136. The drug loading reached 27.69 %, and the efficiency of encapsulation reached as high as 93.25%. The results were better than the other similar researches, this preparation way was successful.

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Wang, X., Z. Yang, Y. Zhang, L. Jing, Y. Zhao, Y. Yan, and K. Sun. "MnO2Supported Pt Nanoparticels with High Electrocatalytic Activity for Oxygen Reduction Reaction." Fuel Cells 14, no. 1 (December 10, 2013): n/a. http://dx.doi.org/10.1002/fuce.201300102.

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A. A. Aljabali, Alaa, Hamid A. Bakshi, Faruck L. Hakkim, Yusuf A. Haggag, Khalid M. Al-Batanyeh, Mazhar S. Al Zoubi, Bahaa Al-Trad, et al. "Albumin Nano-Encapsulation of Piceatannol Enhances Its Anticancer Potential in Colon Cancer Via Downregulation of Nuclear p65 and HIF-1α." Cancers 12, no. 1 (January 1, 2020): 113. http://dx.doi.org/10.3390/cancers12010113.

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Piceatannol (PIC) is known to have anticancer activity, which has been attributed to its ability to block the proliferation of cancer cells via suppression of the NF-kB signaling pathway. However, its effect on hypoxia-inducible factor (HIF) is not well known in cancer. In this study, PIC was loaded into bovine serum albumin (BSA) by desolvation method as PIC–BSA nanoparticles (NPs). These PIC–BSA nanoparticles were assessed for in vitro cytotoxicity, migration, invasion, and colony formation studies and levels of p65 and HIF-1α. Our results indicate that PIC–BSA NPs were more effective in downregulating the expression of nuclear p65 and HIF-1α in colon cancer cells as compared to free PIC. We also observed a significant reduction in inflammation induced by chemical colitis in mice by PIC–BSA NPs. Furthermore, a significant reduction in tumor size and number of colon tumors was also observed in the murine model of colitis-associated colorectal cancer, when treated with PIC–BSA NPs as compared to free PIC. The overall results indicate that PIC, when formulated as PIC–BSA NPs, enhances its therapeutic potential. Our work could prompt further research in using natural anticancer agents as nanoparticels with possible human clinical trails. This could lead to the development of a new line of safe and effective therapeutics for cancer patients.

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Zamorina, S. A., P. V. Khramtsov, M. B. Rayev, V. P. Timganova, M. S. Bochkova, A. I. Nechaev, E. O. Shunkin, O. G. Khaziakhmatova, V. V. Malaschenko, and L. S. Litvinova. "Graphene Oxide Nanoparticels Interaction with Jurkat Cell Line in Cell-IQ System." Doklady Biochemistry and Biophysics 501, no. 1 (November 2021): 438–43. http://dx.doi.org/10.1134/s1607672921060089.

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ZHANG Yang, 张杨, 李学红 LI Xue-hong, and 彭成晓 PENG Cheng-xiao. "Tunable Photoluminescence of ZnO Films with Different Surfaces by The Coating of Au Nanoparticels." Chinese Journal of Luminescence 33, no. 12 (2012): 1299–303. http://dx.doi.org/10.3788/fgxb20123312.1299.

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Droigk, Christine, Marco Maass, and Alfred Mertins. "Direct multi-dimensional Chebyshev polynomial based reconstruction for magnetic particle imaging." Physics in Medicine & Biology 67, no. 4 (February 16, 2022): 045014. http://dx.doi.org/10.1088/1361-6560/ac4c2e.

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Abstract Magnetic Particle Imaging is a tomographic imaging technique that measures the voltage induced due to magnetization changes of magnetic nanoparticle distributions. The relationship between the received signal and the distribution of the nanoparticels is described by the system function. A common method for image reconstruction is using a measured system function to create a system matrix and set up a regularized linear system of equations. Since the measurement of the system matrix is time-consuming, different methods for acceleration have been proposed. These include modeling the system matrix or using a direct reconstruction method in time, known as X-space reconstruction. In this work, based on the simplified Langevin model of paramagnetism and certain approximations, a direct reconstruction technique for Magnetic Particle Imaging in the frequency domain with two- and three-dimensional Lissajous trajectory excitation is presented. The approach uses Chebyshev polynomials of second kind. During reconstruction, they are weighted with the frequency components of the voltage signal and additional factors and then summed up. To obtain the final nanoparticle distribution, this result is rescaled and deconvolved. It is shown that the approach works for both simulated data and real measurements. The obtained image quality is comparable to a modeled system matrix approach using the same simplified physical assumptions and no relaxation effects. The reconstruction of a 31 × 31 × 31 volume takes less than a second and is up to 25 times faster than the state-of-the-art Kaczmarz reconstruction. Besides, the derivation of the proposed method shows some new theoretical aspects of the system function and its well-known observed similarity to tensor products of Chebyshev polynomials of second kind.

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Li, Meng, Liqiang Lin, Ruyan Guo, Amar Bhalla, and Xiaowei Zeng. "Numerical investigation of size effects on mechanical behaviors of Fe nanoparticles through an atomistic field theory." Journal of Micromechanics and Molecular Physics 02, no. 03 (September 2017): 1750010. http://dx.doi.org/10.1142/s2424913017500102.

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At nanoscale, the mechanical response of nanoparticles is largely affected by the particle size. To assess the effects of nanoparticle size (e.g., nanoparticle’s volume, cross-sectional area and length) on mechanical behaviors of bcc Fe nanoparticles under compressive loading, an atomistic field theory was introduced in current study. In the theory, atomistic definitions and continuous local density functions of fundamental physical quantities were derived. Through the atomistic potential-based method, the mechanical responses of bcc Fe nanoparticles were analyzed in different sizes. The simulation results reveal that the ultimate stress decreases as Fe nanoparticle’s volume, cross-sectional area or length increases under compressive loading. Nonetheless, the Young’s modulus increases as nanoparticle size increases. In addition, for a fixed finite volume nanoparticle, this study indicates that the ultimate stress will increase as strain rate increases, but Young’s modulus will decrease with increasing strain rate. A loading–unloading study illustrates the energy dissipation due to irreversible structure changes in Fe nanoparticles.

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Wang, Xijun. "The Magnetic Nanoparticle Movement in Magnetic Fluid Characterized by the Laser Dynamic Speckle Interferometry." Journal of Nanomaterials 2014 (2014): 1–7. http://dx.doi.org/10.1155/2014/287813.

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A dual scanning laser speckle interferometry experiment was designed to observe the dynamic behavior of the magnetic fluid actuated by a magnetic field. In order to improve the spatial resolution of the dynamic speckle measurement, the phase delay scanning was used to compensate the additional phase variation which was caused by the transverse scanning. The correlation coefficients corresponding to the temporal dynamic speckle patterns within the same time interval scattering from the nanoparticles were calculated in the experiment on nanoscale magnetic clusters. In the experiment, the speckle of the magnetic nanoparticle fluid movement has been recorded by the lens unmounted CCD within the interferometry strips, although the speckle led to the distinguished annihilation of the light coherence. The results have showed that the nanoparticle fluid dynamic properties appeared synergistically in the fringe speckles. The analyses of the nanoparticle's relative speed and the speckle pattern moving amount in the fringes have proved the nanoparticle’s movement in a laminar flow in the experiment.

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Karatrantos, Argyrios, Yao Koutsawa, Philippe Dubois, Nigel Clarke, and Martin Kröger. "Miscibility and Nanoparticle Diffusion in Ionic Nanocomposites." Polymers 10, no. 9 (September 10, 2018): 1010. http://dx.doi.org/10.3390/polym10091010.

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We investigate the effect of various spherical nanoparticles in a polymer matrix on dispersion, chain dimensions and entanglements for ionic nanocomposites at dilute and high nanoparticle loading by means of molecular dynamics simulations. The nanoparticle dispersion can be achieved in oligomer matrices due to the presence of electrostatic interactions. We show that the overall configuration of ionic oligomer chains, as characterized by their radii of gyration, can be perturbed at dilute nanoparticle loading by the presence of charged nanoparticles. In addition, the nanoparticle’s diffusivity is reduced due to the electrostatic interactions, in comparison to conventional nanocomposites where the electrostatic interaction is absent. The charged nanoparticles are found to move by a hopping mechanism.

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Xuan, Liang, Li-Jiao Tian, Tian Tian, Xue-Meng Wang, Dian-Hai Yang, and Han-Qing Yu. "In situ synthesizing silver nanoparticels by bio-derived gallic acid to enhance antimicrobial performance of PVDF membrane." Separation and Purification Technology 251 (November 2020): 117381. http://dx.doi.org/10.1016/j.seppur.2020.117381.

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Shannahan, Jonathan. "The biocorona: a challenge for the biomedical application of nanoparticles." Nanotechnology Reviews 6, no. 4 (August 28, 2017): 345–53. http://dx.doi.org/10.1515/ntrev-2016-0098.

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AbstractFormation of the biocorona on the surface of nanoparticles is a significant obstacle for the development of safe and effective nanotechnologies, especially for nanoparticles with biomedical applications. Following introduction into a biological environment, nanoparticles are rapidly coated with biomolecules resulting in formation of the nanoparticle-biocorona. The addition of these biomolecules alters the nanoparticle’s physicochemical characteristics, functionality, biodistribution, and toxicity. To synthesize effective nanotherapeutics and to more fully understand possible toxicity following human exposures, it is necessary to elucidate these interactions between the nanoparticle and the biological media resulting in biocorona formation. A thorough understanding of the mechanisms by which the addition of the biocorona governs nanoparticle-cell interactions is also required. Through elucidating the formation and the biological impact of the biocorona, the field of nanotechnology can reach its full potential. This understanding of the biocorona will ultimately allow for more effective laboratory screening of nanoparticles and enhanced biomedical applications. The importance of the nanoparticle-biocorona has been appreciated for a decade; however, there remain numerous future directions for research which are necessary for study. This perspectives article will summarize the unique challenges presented by the nanoparticle-biocorona and avenues of future needed investigation.

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Wang, Shenqing, Xiliang Yan, Gaoxing Su, and Bing Yan. "Cytotoxicity Induction by the Oxidative Reactivity of Nanoparticles Revealed by a Combinatorial GNP Library with Diverse Redox Properties." Molecules 26, no. 12 (June 14, 2021): 3630. http://dx.doi.org/10.3390/molecules26123630.

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It is crucial to establish relationship between nanoparticle structures (or properties) and nanotoxicity. Previous investigations have shown that a nanoparticle’s size, shape, surface and core materials all impact its toxicity. However, the relationship between the redox property of nanoparticles and their toxicity has not been established when all other nanoparticle properties are identical. Here, by synthesizing an 80-membered combinatorial gold nanoparticle (GNP) library with diverse redox properties, we systematically explored this causal relationship. The compelling results revealed that the oxidative reactivity of GNPs, rather than their other physicochemical properties, directly caused cytotoxicity via induction of cellular oxidative stress. Our results show that the redox diversity of nanoparticles is regulated by GNPs modified with redox reactive ligands.

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Shagdarova, Balzhima, Mariya Konovalova, Yuliya Zhuikova, Alexey Lunkov, Vsevolod Zhuikov, Dolgor Khaydapova, Alla Il’ina, Elena Svirshchevskaya, and Valery Varlamov. "Collagen/Chitosan Gels Cross-Linked with Genipin for Wound Healing in Mice with Induced Diabetes." Materials 15, no. 1 (December 21, 2021): 15. http://dx.doi.org/10.3390/ma15010015.

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Diabetes mellitus continues to be one of the most common diseases often associated with diabetic ulcers. Chitosan is an attractive biopolymer for wound healing due to its biodegradability, biocompatibility, mucoadhesiveness, low toxicity, and hemostatic effect. A panel of hydrogels based on chitosan, collagen, and silver nanoparticels were produced to treat diabetic wounds. The antibacterial activity, cytotoxicity, swelling, rheological properties, and longitudinal sections of hydrogels were studied. The ability of the gels for wound healing was studied in CD1 mice with alloxan-induced diabetes. Application of the gels resulted in an increase in VEGF, TGF-b1, IL-1b, and TIMP1 gene expression and earlier wound closure in a comparison with control untreated wounds. All gels increased collagen deposition, hair follicle repair, and sebaceous glands formation. The results of these tests show that the obtained hydrogels have good mechanical properties and biological activity and have potential applications in the field of wound healing. However, clinical studies are required to compare the efficacy of the gels as animal models do not reproduce full diabetes pathology.

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Xu, Jicheng, Min Zhang, Ping Cao, Benu Adhikari, and Chaohui Yang. "Microorganisms control and quality improvement of stewed pork with carrots using ZnO nanoparticels combined with radio frequency pasteurization." Food Bioscience 32 (December 2019): 100487. http://dx.doi.org/10.1016/j.fbio.2019.100487.

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Elahi, S. M., A. Taghizadeh, A. Hadizadeh, and L. Dejam. "Effect of Thickness and Annealing on Structural and Optical Properties of Bi2Te3 Thin Films Prepared from Bi2Te3 Nanoparticels." International Journal of Thin Films Science and Technology 3, no. 1 (January 1, 2014): 13–18. http://dx.doi.org/10.12785/ijtfst/030103.

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Mohammed, Tawfik Mahmood. "Mathematical modeling of the electronic structure of Titanium dioxide \((TiO_2 )_6\) nanoparticles." University of Aden Journal of Natural and Applied Sciences 24, no. 2 (March 22, 2022): 519–26. http://dx.doi.org/10.47372/uajnas.2020.n2.a19.

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The calculation of the number of atoms of the given dimensional nanoparticle, composed of different type atoms has been researched in this work. The calculations have been carried out for nanoparticles of titanium dioxide. Theoretical visual models have been configured, and quantum – mechanical calculations have been carried out for \((TiO_2 )_6\) nanoparticle. The calculations for titanium dioxide nanoparticle have been carried out on the basis of Gaussian atomic orbitals. Besides, Gaussian functions have been used as atomic orbitals. The numerical values of unknown coefficients of the linear combination of atomic orbitals of the atoms of the titanium nanoparticle have been found from the solution of Hartree–Fock–Roothaan (HFR) equations.The values of orbital energies, ionization potential, and the total electronic energy of titanium dioxide nanoparticles have been determined. The calculations show that ,titanium dioxide nanoparticle is tough, electrophile, and stable dielectric, material. The effective charge of atoms have been calculated, and the theoretical visual mode of titanium dioxide nanopartical have been constructed.

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Sutthavas, Pichaporn, Matthias Schumacher, Kai Zheng, Pamela Habibović, Aldo Roberto Boccaccini, and Sabine van Rijt. "Zn-Loaded and Calcium Phosphate-Coated Degradable Silica Nanoparticles Can Effectively Promote Osteogenesis in Human Mesenchymal Stem Cells." Nanomaterials 12, no. 17 (August 24, 2022): 2918. http://dx.doi.org/10.3390/nano12172918.

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Nanoparticles such as mesoporous bioactive glasses (MBGs) and mesoporous silica nanoparticles (MSN) are promising for use in bone regeneration applications due to their inherent bioactivity. Doping silica nanoparticles with bioinorganic ions could further enhance their biological performance. For example, zinc (Zn) is often used as an additive because it plays an important role in bone formation and development. Local delivery and dose control are important aspects of its therapeutic application. In this work, we investigated how Zn incorporation in MSN and MBG nanoparticles impacts their ability to promote human mesenchymal stem cell (hMSC) osteogenesis and mineralization in vitro. Zn ions were incorporated in three different ways; within the matrix, on the surface or in the mesopores. The nanoparticles were further coated with a calcium phosphate (CaP) layer to allow pH-responsive delivery of the ions. We demonstrate that the Zn incorporation amount and ion release profile affect the nanoparticle’s ability to stimulate osteogenesis in hMSCs. Specifically, we show that the nanoparticles that contain rapid Zn release profiles and a degradable silica matrix were most effective in inducing hMSC differentiation. Moreover, cells cultured in the presence of nanoparticle-containing media resulted in the highest induction of alkaline phosphate (ALP) activity, followed by culturing hMSC on nanoparticles immobilized on the surface as films. Exposure to nanoparticle-conditioned media did not increase ALP activity in hMSCs. In summary, Zn incorporation mode and nanoparticle application play an important role in determining the bioactivity of ion-doped silica nanoparticles.

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Zhang, Yong, Xiao Jing Zhao, Qiang He, Ye Jun, and Qin Po Niu. "Experimental Study of Nanoparticle as Oil Additives." Advanced Materials Research 230-232 (May 2011): 288–92. http://dx.doi.org/10.4028/www.scientific.net/amr.230-232.288.

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Cu nanoparticles as N32 base oil additives were studied in the paper. The structure of Cu nanoparticlcs was characterized by Transmission Electron Microscopy (TEM) and X-ray powder diffraction spectroscope (XRD). The widely used steel-steel friction system was chosen to test the feasibility and practicality of Cu nanoparticles as bearing lubricant additives. The results show that N32 base oil with 0.5% Cu nanoparticle can improve the test sample contact fatigue life than pure N32 base oil.

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Zhao, Jiling, Chen Wang, Shixing Wang, Libo Zhang, and Bing Zhang. "Selective recovery of Au(III) from wastewater by a recyclable magnetic Ni0.6Fe2.4O4 nanoparticels with mercaptothiadiazole: Interaction models and adsorption mechanisms." Journal of Cleaner Production 236 (November 2019): 117605. http://dx.doi.org/10.1016/j.jclepro.2019.117605.

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M. Tóth, Orsolya, Ákos Menyhárt, Rita Frank, Dóra Hantosi, Eszter Farkas, and Ferenc Bari. "Tissue Acidosis Associated with Ischemic Stroke to Guide Neuroprotective Drug Delivery." Biology 9, no. 12 (December 11, 2020): 460. http://dx.doi.org/10.3390/biology9120460.

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Ischemic stroke is a leading cause of death and disability worldwide. Yet, the effective therapy of focal cerebral ischemia has been an unresolved challenge. We propose here that ischemic tissue acidosis, a sensitive metabolic indicator of injury progression in cerebral ischemia, can be harnessed for the targeted delivery of neuroprotective agents. Ischemic tissue acidosis, which represents the accumulation of lactic acid in malperfused brain tissue is significantly exacerbated by the recurrence of spreading depolarizations. Deepening acidosis itself activates specific ion channels to cause neurotoxic cellular Ca2+ accumulation and cytotoxic edema. These processes are thought to contribute to the loss of the ischemic penumbra. The unique metabolic status of the ischemic penumbra has been exploited to identify the penumbra zone with imaging tools. Importantly, acidosis in the ischemic penumbra may also be used to guide therapeutic intervention. Agents with neuroprotective promise are suggested here to be delivered selectively to the ischemic penumbra with pH-responsive smart nanosystems. The administered nanoparticels release their cargo in acidic tissue environment, which reliably delineates sites at risk of injury. Therefore, tissue pH-targeted drug delivery is expected to enrich sites of ongoing injury with the therapeutical agent, without the risk of unfavorable off-target effects.

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Chandra, Arun, and Nalina C. "Review on nanoparticles technology and applications based on drug delivery." IP International Journal of Comprehensive and Advanced Pharmacology 6, no. 3 (October 15, 2021): 117–20. http://dx.doi.org/10.18231/j.ijcaap.2021.021.

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This review is about nanocrystal technology and applications of nanocrystals based on drug delivery. Nanocrystal technology is applied to the drug molecules to access for good drug delivery as nano dimensioned carrier. Nanoparticle has at least one dimension smaller than 100 nanometers. The major properties of nanoparticles are increases dissolution velocity by surface area enlargement and increase in saturation solubility. Nanoparticle’s productions are done with different methods such as precipitation method, Milling method, and homogenized method. Nanoparticles has got wide range of applications based on drug delivery such as gastrointestinal tract, brain, tumor cell targeting, respiratory tract, and gene delivery.

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Fan, Xunqin, Shuan Liu, and Ke Ruan. "Application of magnetic nanoparticles Fe304 in the field of orthopedics and medicine." E3S Web of Conferences 271 (2021): 04041. http://dx.doi.org/10.1051/e3sconf/202127104041.

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Magnetic nanoparticle Fe304 have super paramagnetic, biological cell compatibility, low toxicity, antibiosis and bacteriostasis, drug loading, sustained release and thermal effect. Using magnetic nanoparticies Fe304 as magnetic source, magnetic masoporous glass two-dimensional bone framework was synthesized under the action of external magnetic field, which provides growth space for bone repair, cell proliferation and metabolism, and contribute to mineralizing. The same time, The application of graphene, especially magnetic nanoparticles Fe304, in bone materials, bone repair and relatedmedicalfields was discussed.

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Gulomov, Jasurbek, and Rayimjon Aliev. "The Way of the Increasing Two Times the Efficiency of Silicon Solar Cell." Physics and Chemistry of Solid State 22, no. 4 (December 15, 2021): 756–60. http://dx.doi.org/10.15330/pcss.22.4.756-760.

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Increase of the efficiency of the solar cells which are produced in industry, is important. Increase of efficiency of solar cells was identified, when nanoplasmonics phenomenon was formed in solar cell. So, in this article, influence of nanoparticles Pt, Au, Ag and Cu on properties of silicon based solar cell has been studied. When nanoparticle Pt was inclused in silicon based solar cell, its efficiency increased 2.31 times. Optimal radius of nanoparticule Pt was identified to be between 15-25 nm.

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Caballero-Florán, Isaac H., Hernán Cortés, Fabiola V. Borbolla-Jiménez, Carla D. Florán-Hernández, María L. Del Prado-Audelo, Jonathan J. Magaña, Benjamín Florán, and Gerardo Leyva-Gómez. "PEG 400:Trehalose Coating Enhances Curcumin-Loaded PLGA Nanoparticle Internalization in Neuronal Cells." Pharmaceutics 15, no. 6 (May 25, 2023): 1594. http://dx.doi.org/10.3390/pharmaceutics15061594.

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This work proposes a combination of polyethylene glycol 400 (PEG) and trehalose as a surface modification approach to enhance PLGA-based nanoparticles as a drug carrier for neurons. PEG improves nanoparticles’ hydrophilicity, and trehalose enhances the nanoparticle’s cellular internalization by inducing a more auspicious microenvironment based on inhibiting cell surface receptor denaturation. To optimize the nanoprecipitation process, a central composite design was performed; nanoparticles were adsorbed with PEG and trehalose. PLGA nanoparticles with diameters smaller than 200 nm were produced, and the coating process did not considerably increase their size. Nanoparticles entrapped curcumin, and their release profile was determined. The nanoparticles presented a curcumin entrapment efficiency of over 40%, and coated nanoparticles reached 60% of curcumin release in two weeks. MTT tests and curcumin fluorescence, with confocal imaging, were used to assess nanoparticle cytotoxicity and cell internalization in SH-SY5Y cells. Free curcumin 80 µM depleted the cell survival to 13% at 72 h. Contrariwise, PEG:Trehalose-coated curcumin-loaded and non-loaded nanoparticles preserved cell survival at 76% and 79% under the same conditions, respectively. Cells incubated with 100 µM curcumin or curcumin nanoparticles for 1 h exhibited 13.4% and 14.84% of curcumin’s fluorescence, respectively. Moreover, cells exposed to 100 µM curcumin in PEG:Trehalose-coated nanoparticles for 1 h presented 28% fluorescence. In conclusion, PEG:Trehalose-adsorbed nanoparticles smaller than 200 nm exhibited suitable neural cytotoxicity and increased cell internalization proficiency.

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Albarki, Mohammed A., and Maureen D. Donovan. "Uptake of Cationic PAMAM-PLGA Nanoparticles by the Nasal Mucosa." Scientia Pharmaceutica 90, no. 4 (November 25, 2022): 72. http://dx.doi.org/10.3390/scipharm90040072.

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Nanoparticles provide promising advantages in advanced delivery systems for enhanced drug delivery and targeting. The use of a biodegradable polymer such as PLGA (poly lactic-co-glycolic acid) promotes improved nanoparticle safety and, to some extent, provides the ability to modify nanoparticle surface properties. This study compared the effect of altering the surface charge on the translocation of PLGA nanoparticles across excised nasal mucosal tissues. Nanoparticles (average diameter of 60–100 nm) loaded with Nile Red (lipophilic fluorescent dye) were fabricated using a nanoprecipitation method. The effects of nanoparticle surface charge were investigated by comparing the transfer of untreated nanoparticles (negatively charged) and positively charged PLGA nanoparticles, which were modified using PAMAM dendrimer (polyamidoamine, 5th generation). All nanoparticles were able to be transferred in measurable quantities into both nasal respiratory and olfactory mucosae within 30 min. The total nanoparticle uptake was less than 5% of the nanoparticle mass exposed to the tissue surface. The cationic nanoparticles showed a significantly lower transfer into the mucosal tissues where the amount of nanoparticles transferred was 1.8–4-fold lower compared to the untreated negatively charged nanoparticles. The modification of the nanoparticle surface charge can alter the nanoparticle interaction with the nasal epithelial surface, which can result in decreasing the nanoparticle transfer into the nasal mucosa.

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Li, Shidong, Yeap Hung Ng, Hon Chung Lau, Ole Torsæter, and Ludger P. Stubbs. "Experimental Investigation of Stability of Silica Nanoparticles at Reservoir Conditions for Enhanced Oil-Recovery Applications." Nanomaterials 10, no. 8 (August 4, 2020): 1522. http://dx.doi.org/10.3390/nano10081522.

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To be effective enhanced oil-recovery (EOR) agents, nanoparticles must be stable and be transported through a reservoir. However, the stability of a nanoparticle suspension at reservoir salinity and temperature is still a challenge and how it is affected by reservoir rocks and crude oils is not well understood. In this work, for the first time, the effect of several nanoparticle treatment approaches on the stability of silica nanoparticles at reservoir conditions (in the presence of reservoir rock and crude oil) was investigated for EOR applications. The stability of nanoparticle suspensions was screened in test tubes at 70 °C and 3.8 wt. % NaCl in the presence of reservoir rock and crude oil. Fumed silica nanoparticles in suspension with hydrochloric acid (HCl), polymer-modified fumed nanoparticles and amide-functionalized silica colloidal nanoparticles were studied. The size and pH of nanoparticle suspension in contact with rock samples were measured to determine the mechanism for stabilization or destabilization of nanoparticles. A turbidity scanner was used to quantify the stability of the nanoparticle suspension. Results showed that both HCl and polymer surface modification can improve nanoparticle stability under synthetic seawater salinity and 70 °C. Suspensions of polymer-modified nanoparticles were stable for months. It was found that pH is a key parameter influencing nanoparticle stability. Rock samples containing carbonate minerals destabilized unmodified nanoparticles. Crude oil had limited effect on nanoparticle stability. Some components of crude oil migrated into the aqueous phase consisting of amide-functionalized silica colloidal nanoparticles suspension. Nanoparticles modification or/and stabilizer are necessary for nanoparticle EOR application.

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Maghoul, Amir, Ali Rostami, Samiyeh Matloub, and Amin Pourrezaei. "Design Considerations Influencing Optical Response in Gold Spherical Nanoparticles." Journal of Nano Research 46 (March 2017): 1–11. http://dx.doi.org/10.4028/www.scientific.net/jnanor.46.1.

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In this article, the relations between extinction cross section and Gold nanoparticle's parameters such as dimensions have been investigated. In this work, the extinction cross section of the core-shell nanoparticles is analyzed by changing the shell material and its thickness. By this, the interesting results such as shifting resonant peak in optical response are obtained. Moreover, a new model of nanostructure is proposed in which the resonant peak of extinction cross section can be controlled by adding silicon nanoparticles and impurity in the shell. This method can be used for tuning of the scattering properties of the core-shell nanoparticle. In the following, we demonstrate that the effective epsilon properties can be used for tuning of the desired optical response in the combinational structure of the spherical nanoparticles. At the end, the effective relative epsilon is also calculated for the selected structures. The operational frequency band is selected from 300 (THz) to 900 (THz).

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Bao, Lingling, Chaoyang Zhong, Pengfei Jie, and Yan Hou. "The effect of nanoparticle size and nanoparticle aggregation on the flow characteristics of nanofluids by molecular dynamics simulation." Advances in Mechanical Engineering 11, no. 11 (November 2019): 168781401988948. http://dx.doi.org/10.1177/1687814019889486.

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Molecular dynamics simulation is used to investigate the flow characteristics of Cu–Ar nanofluids considering the influence of nanoparticle size and nanoparticle aggregation. Nanofluids viscosity is calculated by equilibrium molecular dynamics based on Green–Kubo equation. Results demonstrate that the viscosity of nanofluids decreases with the increase of nanoparticle size. In addition, nanoparticle aggregation results in the increase of the nanofluids viscosity. Compared with nanoparticle size, nanoparticle aggregation has a larger impact on viscosity. Nanofluids flowing in parallel-plate nanochannels are simulated. The velocity profiles are studied through three nanoparticle sizes (11.55, 14.55, and 18.33 Å) and four nanoparticle aggregate configurations. Results show that the velocity profile of 14.55 Å nanoparticle size is larger than that of other two nanoparticle sizes. As for four nanoparticles, the nanoparticles clustering as a line leads to the maximum velocity profile, while the nanoparticles clustering as a cube causes the minimum velocity profile. Compared with viscosity, nanoparticle aggregation has a greater effect on the velocity profile. When the nanoparticles are evenly distributed, the influence of viscosity on velocity profiles is dominant. Otherwise, the aggregation, aggregate configuration, and distribution of nanoparticles have a dominant impact on the flow characteristics of nanofluids.

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Olinger, Alexander D., Eric J. Spangler, P. B. Sunil Kumar, and Mohamed Laradji. "Membrane-mediated aggregation of anisotropically curved nanoparticles." Faraday Discussions 186 (2016): 265–75. http://dx.doi.org/10.1039/c5fd00144g.

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Using systematic numerical simulations, we study the self-assembly of elongated curved nanoparticles on lipid vesicles. Our simulations are based on molecular dynamics of a coarse-grained implicit-solvent model of self-assembled lipid membranes with a Langevin thermostat. Here we consider only the case wherein the nanoparticle–nanoparticle interaction is repulsive, only the concave surface of the nanoparticle interacts attractively with the lipid head groups and only the outer surface of the vesicle is exposed to the nanoparticles. Upon their adhesion on the vesicle, the curved nanoparticles generate local curvature on the membrane. The resulting nanoparticle-generated membrane curvature leads in turn to nanoparticle self-assembly into two main types of aggregates corresponding to chain aggregates at low adhesion strengths and aster aggregates at high adhesion strength. The chain-like aggregates are due to the fact that at low values of adhesion strength, the nanoparticles prefer to lie parallel to each other. As the adhesion strength is increased, a splay angle between the nanoparticles is induced with a magnitude that increases with increasing adhesion strength. The origin of the splay angles between the nanoparticles is shown to be saddle-like membrane deformations induced by a tilt of the lipids around the nanoparticles. This phenomenon of membrane mediated self-assembly of anisotropically curved nanoparticles is explored for systems with varying nanoparticle number densities, adhesion strength, and nanoparticle intrinsic curvature.

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Leizou, Kaywood Elijah, and Muhammad Aqeel Ashraf. "GREEN SYNTHESIS APPROACH, CHARACTERIZATION, AND APPLICATIONS OF MgO NANO PARTICLES USING CURRY LEAF (MURRAYA KOENIGII)." Acta Scientifica Malaysia 6, no. 1 (2022): 06–09. http://dx.doi.org/10.26480/asm.01.2022.06.09.

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Nanotechnology has emerged as a state-of-the-art and cutting-edge technology with multifarious applications in a wide array of fields. The goal of this study was to create magnesium oxide nanoparticles using an aqueous extract of curry leaves (murraya koenigii or bergera koenigii). The morphology, elemental content, shape, and size of the produced MgO nanoparticles were determined using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy analysis (EDX). According to the SEM data, the MgO nanoparticle forms were well disseminated, with a spherical shape and particle sizes ranging from 20 to 100 nm. While the EDX pattern infers the sample’s elemental composition, the average occurrence of Mg was 32.45 percent. Plant extracts were used to successfully produce MgO nanoparticlse, which is an essential alternative technique because it is non-toxic, biocompatible, and environmentally benign.

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Michelakaki, Irini, Nikos Boukos, Dimitrios A. Dragatogiannis, Spyros Stathopoulos, Costas A. Charitidis, and Dimitris Tsoukalas. "Synthesis of hafnium nanoparticles and hafnium nanoparticle films by gas condensation and energetic deposition." Beilstein Journal of Nanotechnology 9 (June 27, 2018): 1868–80. http://dx.doi.org/10.3762/bjnano.9.179.

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In this work we study the fabrication and characterization of hafnium nanoparticles and hafnium nanoparticle thin films. Hafnium nanoparticles were grown in vacuum by magnetron-sputtering inert-gas condensation. The as deposited nanoparticles have a hexagonal close-packed crystal structure, they possess truncated hexagonal biprism shape and are prone to surface oxidation when exposed to ambient air forming core–shell Hf/HfO2 structures. Hafnium nanoparticle thin films were formed through energetic nanoparticle deposition. This technique allows for the control of the energy of charged nanoparticles during vacuum deposition. The structural and nanomechanical properties of the nanoparticle thin films were investigated as a function of the kinetic energy of the nanoparticles. The results reveal that by proper adjustment of the nanoparticle energy, hexagonal close-packed porous nanoparticle thin films with good mechanical properties can be formed, without any additional treatment. It is shown that these films can be patterned on the substrate in sub-micrometer dimensions using conventional lithography while their porosity can be well controlled. The fabrication and experimental characterization of hafnium nanoparticles is reported for the first time in the literature.

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Chow, James C. L., and Sama Jubran. "Depth Dose Enhancement in Orthovoltage Nanoparticle-Enhanced Radiotherapy: A Monte Carlo Phantom Study." Micromachines 14, no. 6 (June 10, 2023): 1230. http://dx.doi.org/10.3390/mi14061230.

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Background: This study was to examine the depth dose enhancement in orthovoltage nanoparticle-enhanced radiotherapy for skin treatment by investigating the impact of various photon beam energies, nanoparticle materials, and nanoparticle concentrations. Methods: A water phantom was utilized, and different nanoparticle materials (gold, platinum, iodine, silver, iron oxide) were added to determine the depth doses through Monte Carlo simulation. The clinical 105 kVp and 220 kVp photon beams were used to compute the depth doses of the phantom at different nanoparticle concentrations (ranging from 3 mg/mL to 40 mg/mL). The dose enhancement ratio (DER), which represents the ratio of the dose with nanoparticles to the dose without nanoparticles at the same depth in the phantom, was calculated to determine the dose enhancement. Results: The study found that gold nanoparticles outperformed the other nanoparticle materials, with a maximum DER value of 3.77 at a concentration of 40 mg/mL. Iron oxide nanoparticles exhibited the lowest DER value, equal to 1, when compared to other nanoparticles. Additionally, the DER value increased with higher nanoparticle concentrations and lower photon beam energy. Conclusions: It is concluded in this study that gold nanoparticles are the most effective in enhancing the depth dose in orthovoltage nanoparticle-enhanced skin therapy. Furthermore, the results suggest that increasing nanoparticle concentration and decreasing photon beam energy lead to increased dose enhancement.

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Chavanpatil, Mahesh D., Ayman Khdair, and Jayanth Panyam. "Nanoparticles for Cellular Drug Delivery: Mechanisms and Factors Influencing Delivery." Journal of Nanoscience and Nanotechnology 6, no. 9 (September 1, 2006): 2651–63. http://dx.doi.org/10.1166/jnn.2006.443.

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Polymeric nanoparticles have demonstrated enormous potential as cellular drug delivery vehicles. Nanoparticles improve drug's stability as well as its availability and retention at the target intracellular site of action. Therapeutic efficacy of nanoparticles can be further enhanced by conjugating specific ligands to nanoparticle surface. Ligand conjugation can also be used to favorably modify the intracellular disposition of nanoparticles. A number of ligands are available for this purpose; use of a specific ligand depends on the target cell, the material used for nanoparticle formulation, and the chemistry available for ligand-nanoparticle conjugation. Cellular drug delivery using nanoparticles is also affected by clearance through the reticuloendothelial system. In this paper, we review the recent progress on our understanding of physicochemical factors that affect the cellular uptake of nanoparticles and the different cellular processes that could be exploited to enhance nanoparticle uptake into cells.

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Nakamura, Michihiro. "Biomedical applications of organosilica nanoparticles toward theranostics." Nanotechnology Reviews 1, no. 6 (December 1, 2012): 469–91. http://dx.doi.org/10.1515/ntrev-2012-0005.

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AbstractNanoparticles for biomedical applications have several advantages as multifunctional agents. Among various types of nanoparticles for biomedical applications, silica nanoparticles have characteristic positioning due to their inherent property. The recent development of silica nanoparticles is creating a new trend in nanomedicine. A novel type of silica nanoparticle, organosilica nanoparticle, is both structurally and functionally different from the common (inorgano)silica nanoparticle. The organosilica nanoparticles are inherent organic-inorganic hybrid nanomaterials. The interior and exterior functionalities of organosilica nanoparticles are useful for their multifunctionalization. Biomedical applications of organosilica nanoparticles are leading to a wide range of nanomedical fields such as basic biomedical investigations and clinical applications. Multifunctionalizations peculiar to organosilica nanoparticles enable the creation of novel imaging systems and therapeutic applications. In this review, I will introduce differences between (inorgano)silica nanoparticles and organosilica nanoparticles, and then focus on biomedical applications of organosilica nanoparticles toward theranostics.

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Bertholon, Isabelle, Gilles Ponchel, Denis Labarre, Patrick Couvreur, and Christine Vauthier. "Bioadhesive Properties of Poly(alkylcyanoacrylate) Nanoparticles Coated with Polysaccharide." Journal of Nanoscience and Nanotechnology 6, no. 9 (September 1, 2006): 3102–9. http://dx.doi.org/10.1166/jnn.2006.418.

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Development of bioadhesive nanoparticles is of great interest to improve drug absorption through the intestinal barrier. Various Polysaccharide-coated poly(alkylcyanoacrylate) nanoparticles were prepared. The bioadhesive properties of the nanoparticles coated with dextran or chitosan in end-on or side-on conformation were evaluated with an ex-vivo adsorption experiment on rat intestine. Results show that diffusion of nanoparticles in mucus layer was governed by the nanoparticle diameter and isotherms of adsorption were influenced by the nature of polysaccharide used. High amount of nanoparticles coated with chitosan can be entrapped in the mucus layer even at low nanoparticle concentration in suspension. When nanoparticle concentration increased, a pseudo-plateau was reached. In the case of dextran-coated nanoparticles, linear increase of adsorption was observed and no saturation phenomenon was highlighted over the range of nanoparticle concentration used in this study. These results suggested that interactions involved in bioadhesion mechanism depended on the nature of polysaccharide. Electrostatic interactions are enhanced between chitosan-coated nanoparticles and glycoproteins of mucus leading to a saturated adsorption phenomenon whereas dextran-coated nanoparticles interacted by non-electrostatic interactions with mucus resulting in a non-saturated phenomenon. Polysaccharides grafted at the nanoparticle surface in the brush conformation appeared more favorable to promote interactions of nanoparticles with glycoproteins of mucus in comparison with the more compact loop conformation of polysaccharide chains.

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Zhang, Tiantian, Michael J. Murphy, Haiyang Yu, Hitesh G. Bagaria, Ki Youl Yoon, Bethany M. Neilson, Christopher W. Bielawski, Keith P. Johnston, Chun Huh, and Steven L. Bryant. "Investigation of Nanoparticle Adsorption During Transport in Porous Media." SPE Journal 20, no. 04 (August 20, 2015): 667–77. http://dx.doi.org/10.2118/166346-pa.

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Summary Nanoparticles (diameter of approximately 5 to 50 nm) easily pass through typical pore throats in reservoirs, but physicochemical attraction between nanoparticles and pore walls may still lead to significant retention. We conducted an extensive series of nanoparticle-transport experiments in core plugs and in columns packed with crushed sedimentary rock, systematically varying flow rate, type of nanoparticle, injection-dispersion concentration, and porous-medium properties. Effluent-nanoparticle-concentration histories were measured with fine resolution in time, enabling the evaluation of nanoparticle adsorption in the columns during slug injection and post-flushes. We also applied this analysis to nanoparticle-transport experiments reported in the literature. Our analysis suggests that nanoparticles undergo both reversible and irreversible adsorption. Effluent-nanoparticle concentration reaches the injection concentration during slug injection, indicating the existence of an adsorption capacity. Experiments with a variety of nanoparticles and porous media yield a wide range of adsorption capacities (from 10–5 to 101 mg/g for nanoparticles and rock, respectively) and also a wide range of proportions of reversible and irreversible adsorption. Reversible- and irreversible-adsorption sites are distinct and interact with nanoparticles independently. The adsorption capacities are typically much smaller than monolayer coverage. Their values depend not only on the type of nanoparticle and porous media, but also on the operating conditions, such as injection concentration and flow rate.

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Murei, A., K. Pillay, and A. Samie. "Syntheses, Characterization, and Antibacterial Evaluation of P. grandiflora Extracts Conjugated with Gold Nanoparticles." Journal of Nanotechnology 2021 (December 24, 2021): 1–10. http://dx.doi.org/10.1155/2021/8687627.

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Background. With the recent increase in antibiotic resistance to conventional antibiotics, gold nanoparticles, and medicinal plants, extracts present an interesting alternative. Objectives. This study aimed to synthesize, characterize, and evaluate Pyrenacantha grandiflora Baill extracts and gold nanoparticle conjugates against pathogenic bacteria. Methods. We synthesized gold nanoparticles by chemical and biological methods. The nanoparticles were characterized by the use of UV-visible spectrophotometry, followed by transmission electron microscopy (TEM) and energy-dispersive X-ray analysis (EDX). Gold nanoparticles were conjugated to plant extracts and analyzed with a Fourier-transform infrared spectroscope (FTIR). We determined the antimicrobial activity of the conjugates using well diffusion and the microdilution assays. Results. The UV–visible spectra of gold nanoparticles showed a synthesis peak at 530 nm. FTIR analysis indicated functional biomolecules that were associated with plant extract conjugated gold nanoparticles; the formation of C–H group and carbonyl (C=O) groups, –OH carbonyl, and C≡C groups were also observed. Biologically synthesized nanoparticles were star-shaped when observed by TEM with an average size of 11 nm. Gold nanoparticles synthesized with P. grandiflora water extracts showed the largest zone of inhibition (22 mm). When the gold nanoparticles synthesized by the biological method were conjugated with acetone extracts of P. grandiflora, MIC as low as 0.0063 mg/mL was observed against beta-lactamase producing K. pneumonia. The activity of acetone extracts was improved with chemically synthesized gold nanoparticles particularly when beta-lactamase producing E. coli and MRSA were used as test organisms. A synergistic effect was observed against all tested bacteria, except for MRSA when gold nanoparticles were conjugated with acetone extract. Conclusion. Overall, P. grandiflora tuber extracts conjugated with gold nanoparticles showed a very good antibacterial activity that improved both plant extract and gold nanoparticle’s individual activity.

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Osaci, Mihaela, and Matteo Cacciola. "Influence of the magnetic nanoparticle coating on the magnetic relaxation time." Beilstein Journal of Nanotechnology 11 (August 12, 2020): 1207–16. http://dx.doi.org/10.3762/bjnano.11.105.

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Colloidal systems consisting of monodomain superparamagnetic nanoparticles have been used in biomedical applications, such as the hyperthermia treatment for cancer. In this type of colloid, called a nanofluid, the nanoparticles tend to agglomeration. It has been shown experimentally that the nanoparticle coating plays an important role in the nanoparticle dispersion stability and biocompatibility. However, theoretical studies in this field are lacking. In addition, the ways in which the nanoparticle coating influences the magnetic properties of the nanoparticles are not yet understood. In order to fill in this gap, this study presents a numerical simulation model that elucidates how the nanoparticle coating affects the nanoparticle agglomeration tendency as well as the effective magnetic relaxation time of the system. To simulate the self-organization of the colloidal nanoparticles, a stochastic Langevin dynamics method was applied based on the effective Verlet-type algorithm. The Néel magnetic relaxation time was obtained via the Coffey method in an oblique magnetic field, adapted to the local magnetic field on a nanoparticle.

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Johnston, Stuart T., Matthew Faria, and Edmund J. Crampin. "An analytical approach for quantifying the influence of nanoparticle polydispersity on cellular delivered dose." Journal of The Royal Society Interface 15, no. 144 (July 2018): 20180364. http://dx.doi.org/10.1098/rsif.2018.0364.

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Nanoparticles provide a promising approach for the targeted delivery of therapeutic, diagnostic and imaging agents in the body. However, it is not yet fully understood how the physico-chemical properties of the nanoparticles influence cellular association and uptake. Cellular association experiments are routinely performed in an effort to determine how nanoparticle properties impact the rate of nanoparticle–cell association. To compare experiments in a meaningful manner, the association data must be normalized by the amount of nanoparticles that arrive at the cells, a measure referred to as the delivered dose. The delivered dose is calculated from a model of nanoparticle transport through fluid. A standard assumption is that all nanoparticles within the population are monodisperse, namely the nanoparticles have the same physico-chemical properties. We present a semi-analytic solution to a modified model of nanoparticle transport that allows for the nanoparticle population to be polydisperse. This solution allows us to efficiently analyse the influence of polydispersity on the delivered dose. Combining characterization data obtained from a range of commonly used nanoparticles and our model, we find that the delivered dose changes by more than a factor of 2 if realistic amounts of polydispersity are considered.

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Johnstone, Sharon, Steven Ansell, Sherwin Xie, Lawrence Mayer, and Paul Tardi. "The Use of Radioactive Marker as a Tool to Evaluate the Drug Release in Plasma and Particle Biodistribution of Block Copolymer Nanoparticles." Journal of Drug Delivery 2011 (July 7, 2011): 1–9. http://dx.doi.org/10.1155/2011/349206.

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Diblock copolymer nanoparticles encapsulating a paclitaxel prodrug, Propac 7, have been used to demonstrate the usefulness of a nonmetabolizable radioactive marker, cholesteryl hexadecyl ether (CHE), to evaluate nanoparticle formulation variables. Since CHE did not exchange out of the nanoparticles, the rate of clearance of the CHE could be used as an indicator of nanoparticle stability in vivo. We simultaneously monitored prodrug circulation and carrier circulation in the plasma and the retention of CHE relative to the retention of prodrug in the plasma was used to distinguish prodrug release from nanoparticle plasma clearance. Nanoparticles labelled with CHE were also used to evaluate accumulation of nanoparticles in the tumour. This marker has provided relevant data which we have applied to optimise our nanoparticle formulations.

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Hou, Qi Qi, Xiao Ming Pan, and Wei Zheng. "The Study of New Type of Double Metal Nanofluids Suspension Stability." Applied Mechanics and Materials 440 (October 2013): 54–60. http://dx.doi.org/10.4028/www.scientific.net/amm.440.54.

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This paper made two types metal nanoparticles whose laws of motion had bigger different into ethylene glycol became a new type of double metals nanofluids coolant, and through theoretical analysis and experimental observations to research the different of aggregation properties with single metal nanofluids coolant. Research results of theoretical analysis showed that particles motion laws were the important element of nanoparticle aggregation, because of differences in movement, as the same conditions, double metals nanoparticles had the advantage of aggregation number and equivalent diameter of poly group better than single metal nanoparticles. Experimental results showed that through light beam transmittance test, we knew that the transmitting light degree of homogeneity of double metal nanofluids coolant was better than single metal nanofluids coolants; through contrast TME photos, we got nanoparticle aggregation state of three types of metal nanoparticles, and knew the otherness of nanoparticle aggregation state between double metal nanoparticles and Cu nanoparticles and Ag nanoparticles. This paper provides a scientific attempt to solve nanoparticles aggregation.

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Almehmady, Alshaimaa M., Khalid M. El-Say, Manal A. Mubarak, Haneen A. Alghamdi, Njood A. Somali, Alaa Sirwi, Rahmah Algarni, and Tarek A. Ahmed. "Enhancing the Antifungal Activity and Ophthalmic Transport of Fluconazole from PEGylated Polycaprolactone Loaded Nanoparticles." Polymers 15, no. 1 (December 31, 2022): 209. http://dx.doi.org/10.3390/polym15010209.

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Fungal eye infections are caused mainly by an eye injury and can result in serious eye damage. Fluconazole (FLZ), a broad-spectrum antifungal agent, is a poorly soluble drug with a risk of hepatotoxicity. This work aimed to investigate the antifungal activity, ocular irritation, and transport of FLZ-loaded poly (ε-caprolactone) nanoparticles using a rabbit eye model. Three formulation factors affecting the nanoparticle’s size, zeta potential, and entrapment efficiency were optimized utilizing the Box-Behnken design. Morphological characteristics and antifungal activity of the optimized nanoparticles were studied. The optimized nanoparticles were loaded into thermosensitive in situ hydrogel and hydroxypropylmethylcellulose (HPMC) hydrogel ophthalmic formulations. The rheological behavior, in vitro release and in vivo corneal transport were investigated. Results revealed that the percentage of poly (ε-caprolactone) in the nanoparticle matrix, polymer addition rate, and mixing speed significantly affected the particle size, zeta potential, and entrapment efficiency. The optimized nanoparticles were spherical in shape and show an average size of 145 nm, a zeta potential of −28.23 mV, and a FLZ entrapment efficiency of 98.2%. The antifungal activity of FLZ-loaded nanoparticles was significantly higher than the pure drug. The developed ophthalmic formulations exhibited a pseudoplastic flow, prolonged the drug release and were found to be non-irritating to the cornea. The prepared FLZ pegylated nanoparticles were able to reach the posterior eye segment without eye irritation. As a result, the developed thermosensitive in situ hydrogel formulation loaded with FLZ polymeric nanoparticles is a promising drug delivery strategy for treating deep fungal eye infections.

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Foster, Shelby L., Katie Estoque, Michael Voecks, Nikki Rentz, and Lauren F. Greenlee. "Removal of Synthetic Azo Dye Using Bimetallic Nickel-Iron Nanoparticles." Journal of Nanomaterials 2019 (March 19, 2019): 1–12. http://dx.doi.org/10.1155/2019/9807605.

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Bimetallic nanoparticles comprised of iron (Fe) and nickel (Ni) were investigated for the removal of an azo dye contaminant in water. Morphology (core shell and alloy) and metal molar ratio (Ni2Fe10, Ni5Fe10, and Ni10Fe10) were tested as key nanoparticle properties. The shelf life of the nanoparticles was tested over a 3-week period, and the effect of initial nanoparticle concentration on dye removal was evaluated. The highest initial nanoparticle concentration (1000 mg/L) showed consistent Orange G removal and the greatest extent of dye removal, as compared to the other tested concentrations (i.e., 750 mg/L, 500 mg/L, and 250 mg/L) for the same nanoparticle morphology and metal molar ratio. The metal molar ratio significantly affected the performance of the core shell morphology, where overall dye removal was found to be 66%, 89%, and 98% with an increasing molar ratio (Ni2Fe10 → Ni5Fe10 → Ni10Fe10). In contrast, the overall removal of the dye for all molar ratios of the alloy nanoparticles only resulted in a variability of ±0.005%. When stored in water for 3 weeks, core shell nanoparticles lost reactivity with an average>17% loss in removal with each passing week. However, the alloy nanoparticles were able to continually remove Orange G from solution after 3 weeks of storage to ~97% when used at a starting nanoparticle concentration of 1000 mg/L. Overall, the Ni2Fe10, Ni5Fe10, and Ni10Fe10 alloy nanoparticles with a starting nanoparticle concentration of 1000 mg/L resulted in the greatest dye removal of 97%, 99%, and 98%, respectively. Kinetic rate models were used to analyze dye removal rate constants as a function of nanoparticle properties. Kinetic rate models were seen to differ from core shell (first-order kinetics) to alloy morphology (second-order kinetics). Alloy nanoparticles resulted in as high as X kinetic rate constant, and core shell nanoparticles resulted in as high as XX kinetic rate constant. Metal leaching from the nanoparticles was investigated; alloy nanoparticles resulted in leaching of 3% Fe and 5% Ni which is similar to core shell leaching of 3.2% Fe and 4.3% Ni from the Fe10Ni10 nanoparticles.

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Markova, I. N., M. B. Piskin, I. Z. Zahariev, E. Hristoforou, V. L. Milanova, D. I. Ivanova, and L. B. Fachikov. "Influence of the Support on the Morphology of Co-Sn, Ni-Sn, Co-Ni Nanoparticles Synthesized Through a Borohydride Reduction Method Applying a Template Technique." REVIEWS ON ADVANCED MATERIALS SCIENCE 55, no. 1 (April 1, 2018): 82–91. http://dx.doi.org/10.1515/rams-2018-0031.

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Abstract Intermetallic (Co-Sn, Ni-Sn, Co-Ni) nanoparticles have been synthesized through a borohydride reduction with NaBH4 in aqueous solutions of the chloride salts of Co, Ni, Sn at room temperature using a template technique with a carbon support. As a result nanocomposite materials have been obtained in situ. The ratio of the metallic components has been chosen according the phase diagrams of the relevant binary (Co-Sn, Ni-Sn, Co-Ni) systems: Co:Sn=35:65, Ni:Sn=45:55, Co:Ni=50:50. As carbon supports have been used graphite and carbon powder. To avoid the nanoparticle’s aggregation b-cyclodextrin has been added to the reaction solutions. To study the influence of the supports used on the morphology, specific surface area, elemental and phase composition of the synthesized intermetallic nanoparticles and their carbon nanocomposites SEM, EDS, BET, and XRD investigation techniques have been used. The particle’s morphology varies with the different supports, but in the all cases it is typical for alloyed materials. The nanoparticles are different in shape and size and exhibit a tendency to aggregate. The last-one is due to the unsaturated nanoparticle’s surface and the existing magnetic forces. Regardless of the elemental composition, the nanosized particles are characterized by a relatively high specific surface area (SSA). The Ni-Sn nanoparticle have the largest SSA (80 m2/g), while the Co-Sn particles have the lowest SSA (69 m2/g). The use of a carrier modifies the SSA of the resulting nanocomposites differently depending on the size and shape of the carrier’s particles. The studies conducted on the intermetallic nanoparticles synthesized with various carriers demonstrate that the particle’s morphology, size, and specific surface area for the different supports are suitable for use as catalysts, electrode materials in Li-ion batteries and as magnetic materials for biomedical applications.

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Cagliani, Roberta, Francesca Gatto, and Giuseppe Bardi. "Protein Adsorption: A Feasible Method for Nanoparticle Functionalization?" Materials 12, no. 12 (June 21, 2019): 1991. http://dx.doi.org/10.3390/ma12121991.

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Nanomaterials are now well-established components of many sectors of science and technology. Their sizes, structures, and chemical properties allow for the exploration of a vast range of potential applications and novel approaches in basic research. Biomedical applications, such as drug or gene delivery, often require the release of nanoparticles into the bloodstream, which is populated by blood cells and a plethora of small peptides, proteins, sugars, lipids, and complexes of all these molecules. Generally, in biological fluids, a nanoparticle’s surface is covered by different biomolecules, which regulate the interactions of nanoparticles with tissues and, eventually, their fate. The adsorption of molecules onto the nanomaterial is described as “corona” formation. Every blood particulate component can contribute to the creation of the corona, although small proteins represent the majority of the adsorbed chemical moieties. The precise rules of surface-protein adsorption remain unknown, although the surface charge and topography of the nanoparticle seem to discriminate the different coronas. We will describe examples of adsorption of specific biomolecules onto nanoparticles as one of the methods for natural surface functionalization, and highlight advantages and limitations. Our critical review of these topics may help to design appropriate nanomaterials for specific drug delivery.

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Rani N., Usha, Pavani P, and Prasad Rao P. T. S. R. K. "GREEN SYNTHESIS OF MANGANESE OXIDE NANOPARTICLES USING KIGELIA AFRICANA (LAM.) BENTH. AQUEOUS ROOT EXTRACT AND INFLUENCE ON CHICKPEA (CICER ARIETINUM LINN.) SEED GERMINATION AND PLANT GROWTH." Indian Drugs 59, no. 04 (June 1, 2022): 34–39. http://dx.doi.org/10.53879/id.59.04.13009.

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Use of different seed priming treatments improves seed germination and thus increases plant growth and yield potential. Eco-friendly, cost-effective, simple, and effective seed treatments need to be developed for a high-consuming crop like chickpea (Cice rarietinum Lin.). In the present study, manganese oxide nanoparticles were synthesized using an aqueous extract of roots of Kigelia africana (Lam.) Benth and used as nano priming agents for chickpea seeds. The synthesized nanoparticles were found to have rod-like morphology with heterogeneous size distribution. The nanoparticle’s average size was found to be 67 nm with a metal content of 52.04 %. The sprout’s emergence was found to be high in nanometal-treated chickpea seeds than in untreated and metal treated seeds. The seedling rate after ten days of sowing was found to be high in nanoparticle-treated seeds. The nanometal treatment shows low mean germination time, high germination rate, root length and shoot length of the chickpea compared to untreated samples. The present study results demonstrates that seed priming with manganese oxide nanoparticles could enhance seed germination and growth through an eco-friendly and sustainable nanotechnological approach.

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Journal articles on the topic 'Nanoparticels'

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