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drug-release
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Characterization and antibacterial performance of electrodeposited chitosan–vancomycin composite coatings for prevention of implant-associated infections [electronic resource]
, Article Journal of Materials Science and Engineering: C ; 1 August 2014, Volume 41, Pages 240–248 ; Tamjid, E ; Simchi, A. (Abdolreza) ; Sharif University of Technology
Abstract
Orthopaedic implant-associated infections are one of the most serious complications in orthopaedic surgery and a major cause of implant failure. In the present work, drug-eluting coatings based on chitosan containing various amounts of vancomycin were prepared by a cathodic electrophoretic deposition process on titanium foils. A three-step release mechanism of the antibiotic from the films in a phosphate-buffered saline solution was noticed. At the early stage, physical encapsulation of the drug in the hydrogel network controlled the release rate. At the late stage, however, in vitro degradation/deattachment of chitosan was responsible for the controlled release. Cytotoxicity evaluation of...
Magnetic pH-responsive nanocarrier with long spacer length and high colloidal stability for controlled delivery of doxorubicin
, Article Colloids and Surfaces B: Biointerfaces ; Vol. 116 , April , 2014 , pp. 49-54 ; ISSN: 09277765 ; Hosseini, S. H ; Alizadeh, M ; Bennett, C ; Sharif University of Technology
Abstract
A novel magnetic nanocarrier with long spacer length and high colloidal stability has been prepared for effective delivery of doxorubicin (DOX). First, poly(amidoamine) (PAMAM) dendrimer was grown up onto the surface of superparamagnetic iron oxide nanoparticles to increase the loading amount of amine groups. Then, terminal amine groups were functionalized by polyethylene glycol dimethylester to increase the spacer length. Then anticancer drug DOX was covalently attached onto the system by hydrazone bond to forms a pH-sensitive nanocarrier. This system is designed to combine the advantage of magnetic targeting, high drug loading capacity, and controlled release
Magnetic/pH-sensitive κ-carrageenan/sodium alginate hydrogel nanocomposite beads: Preparation, swelling behavior, and drug delivery
, Article Journal of Biomaterials Science, Polymer Edition ; Vol. 25, issue. 17 , 2014 , p. 1891-1906 ; Rahmani, Z ; Karami, S ; Pourjavadi, A ; Sharif University of Technology
Abstract
This work describes the preparation of magnetic and pH-sensitive beads based on κ-carrageenan and sodium alginate for use as drug-targeting carriers. Physical cross-linking using K+/Ca2+ ions was applied to obtain ionic cross-linked magnetic hydrogel beads. The produced magnetite beads were thoroughly characterized by TEM, SEM/EDS, XRD, FTIR, and VSM techniques. While the water absorbency (WA) of magnetic beads was enhanced by increasing the weight ratio of κ-carrageenan, introducing magnetic nanoparticles caused a decrease in WA capacity from 15.4 to 6.3 g/g. Investigation on the swelling of the hydrogel beads in NaCl, KCl, and CaCl2 solutions revealed the disintegration of beads depending...
Magnetic nanoparticles-loaded PLA/PEG microspheres as drug carriers
, Article Journal of Biomedical Materials Research - Part A ; Vol. 103, issue. 5 , SEP , 2014 , p. 1893-1898 ; Shamshiri, S ; Sharif University of Technology
Abstract
Surface-modified magnetite (Fe3O4) nanoparticles with an average size of 22 nm were prepared. The nanoparticles had a saturation magnetization of 50.7 emu g-1. Then magnetite and drug-loaded microspheres of poly (lactic acid)/poly (ethylene glycol) were prepared at various compositions. The microspheres were spherical in shape and had smooth surface. The diameter size of the microspheres ranged between about 0.2 and 4 μm. Doxorubicin hydrochloride for cancer treatment was the drug that loaded into the microspheres. The prepared microspheres were characterized by FTIR, XRD, VSM, SEM and drug-release measurements. It was found that the drug cumulative release percentage was proportional to...
Applications of stimuli responsive hydrogels: A textile engineering approach
, Article Journal of the Textile Institute ; Volume 104, Issue 11 , 2013 , Pages 1145-1155 ; 00405000 (ISSN) ; Hemmati Nejad, N ; Pourjavadi, A ; Sharif University of Technology
2013
Abstract
Stimuli responsive hydrogels (SRHs) are smart materials with reversible changes in their properties through the environmental stimulus variations. Although SRHs have been used in various medical applications such as sensors, drug release systems and, etc., they are still being actively researched on other sectors such as functional textiles and smart clothing. One of the best methods to produce textiles with more functionality is smart finishing of textile by surface modifying stimuli responsive hydrogels. In this paper, literatures on SRHs applications, methods and application of some SRHs on textile have been thoroughly discussed
Thermo- and pH-sensitive dendrosomes as bi-phase drug delivery systems
, Article Nanomedicine: Nanotechnology, Biology, and Medicine ; Volume 9, Issue 8 , 2013 , Pages 1203-1213 ; 15499634 (ISSN) ; Fard, A. K ; Abedi, F ; Chegeni, B. K ; Bani, F ; Sharif University of Technology
2013
Abstract
Fully supramolecular dendrosomes (FSD) as bi-phase drug delivery systems are reported in this work. For preparation of FSD, amphiphilic linear-dendritic supramolecular systems (ALDSS) have been synthesized by host-guest interactions between hyperbranched polyglycerol having β-cyclodextrin core and bi-chain polycaprolactone (BPCL) with a fluorescine focal point. Self-assembly of ALDSS in aqueous solutions led to FSD. They were able to encapsulate paclitaxel with a high loading capacity. The dendrosome-based drug delivery systems were highly sensitive to pH and temperature. They were stable at 20-37. °C and pH7-8, but dissociated and released drug at temperatures lower than 20. °C or higher...
Fully supramolecular vesicles as anticancer drug delivery systems
, Article New Journal of Chemistry ; Volume 37, Issue 2 , 2013 , Pages 295-298 ; 11440546 (ISSN) ; Adeli, M ; Yazdi, M ; Sharif University of Technology
2013
Abstract
A supramolecular linear-dendritic copolymer consisting of a polystyrene backbone and hanging hyperbranched polyglycerols was prepared and characterized. Host-guest interactions between β-cyclodextrin incorporated in the core of polyglycerol as a host and aromatic rings of polystyrene as guests lead to the formation of a supramolecular linear-dendritic copolymer. Supramolecules formed micelles in aqueous solutions which were able to encapsulate and transfer paclitaxel with a high loading capacity
PLA microspheres-embedded pva hydrogels prepared by gamma-irradiation and freeze-thaw methods as drug release carriers
, Article International Journal of Polymeric Materials and Polymeric Biomaterials ; Volume 62, Issue 1 , 2013 , Pages 28-33 ; 00914037 (ISSN) ; Dadbin, S ; Frounchi, M ; Sharif University of Technology
2013
Abstract
A drug delivery system based on poly (vinyl alcohol) (PVA) hydrogels containing ibuprofen-loaded poly (lactic acid) (PLA) microspheres was developed to improve the release kinetics of this model drug. Gamma-irradiation and freeze-thawing were applied to prepare poly (vinyl alcohol) hydrogels. Properties and morphology of these composite hydrogels were investigated using FTIR, DSC, and SEM. In vitro release indicated that entrapment of the microspheres into the PVA hydrogels causes a reduction in both the release rate and the initial burst effect. PLA microspheres entrapped into the PVA hydrogels showed more suitable controlled release kinetics for drug delivery
Design of pH-responsive nanoparticles of terpolymer of poly(methacrylic acid), polysorbate 80 and starch for delivery of doxorubicin
, Article Colloids and Surfaces B: Biointerfaces ; Volume 101 , January , 2013 , Pages 405-413 ; 09277765 (ISSN) ; Chan, H. K ; Raval, G ; Abdekhodaie, M. J ; Liu, Q ; Heerklotz, H ; Wu, X. Y ; Sharif University of Technology
2013
Abstract
This work focused on the design of new pH-responsive nanoparticles for controlled delivery of anticancer drug doxorubicin (Dox). Nanoparticles of poly(methacrylic acid)-polysorbate 80-grafted starch (PMAA-PS 80-g-St) were synthesized by using a one-pot method that enabled simultaneous grafting of PMAA and PS 80 onto starch and nanoparticle formation in an aqueous medium. The particles were characterized by FTIR, 1H NMR, TEM, DLS, and potentiometric titration. Dox loading and in vitro release from the nanoparticles were investigated. The FTIR and 1H NMR confirmed the chemical composition of the graft terpolymer. The nanoparticles were relatively spherical with narrow size distribution and...
A correlative model to predict in vivo AUC for nanosystem drug delivery with release rate-limited absorption
, Article Journal of Pharmacy and Pharmaceutical Sciences ; Volume 15, Issue 4 , 2012 , Pages 583-591 ; 14821826 (ISSN) ; Mohammadi, K ; Mohammadi, G ; Valizadeh, H ; Barzegar Jalali, A ; Adibkia, K ; Nokhodchi, A ; Sharif University of Technology
2012
Abstract
Purpose. Drug release from nanosystems at the sites of either absorption or effect biophase is a major determinant of its biological action. Thus, in vitro drug release is of paramount importance in gaining insight for the systems performance in vivo. Methods. A novel in vitro in vivo correlation, IVIVC, model denoted as double reciprocal area method was presented and applied to 19 drugs from 55 nano formulations with total 336 data, gathered from literature. Results. The proposed model correlated the in vitro with in vivo parameters with overall error of 12.4 ± 3.9%. Also the trained version of the model predicted the test formulations with overall error of 15.8 ± 3.7% indicating the...
Synthesis of new hybrid nanomaterials: Promising systems for cancer therapy
, Article Nanomedicine: Nanotechnology, Biology, and Medicine ; Volume 7, Issue 6 , 2011 , Pages 806-817 ; 15499634 (ISSN) ; Kalantari, M ; Parsamanesh, M ; Sadeghi, E ; Mahmoudi, M ; Sharif University of Technology
2011
Abstract
Polyrotaxanes consisting of cyclodextrin rings, polyethylene glycol axes and quantum dot (QD) stoppers were synthesized and characterized. The molecular self-assembly of polyrotaxanes led to spindlelike nano-objects whose shape, size and position were dominated by QD stoppers. Due to their well-defined molecular self-assemblies, carbohydrate backbone, high functionality and several types of functional groups together with the high luminescence yield, synthesized hybrid nanostructures were recognized as promising candidates for biomedical applications. The potential applications of the molecular self-assemblies as drug-delivery systems was investigated by conjugation of doxorubicin (DOX) to...
Superparamagnetic iron oxide nanoparticles (SPIONs): Development, surface modification and applications in chemotherapy
, Article Advanced Drug Delivery Reviews ; Volume 63, Issue 1-2 , January–February , 2011 , Pages 24-46 ; 0169409X (ISSN) ; Sant, S ; Wang, B ; Laurent, S ; Sen, T ; Sharif University of Technology
2011
Abstract
At present, nanoparticles are used for various biomedical applications where they facilitate laboratory diagnostics and therapeutics. More specifically for drug delivery purposes, the use of nanoparticles is attracting increasing attention due to their unique capabilities and their negligible side effects not only in cancer therapy but also in the treatment of other ailments. Among all types of nanoparticles, biocompatible superparamagnetic iron oxide nanoparticles (SPIONs) with proper surface architecture and conjugated targeting ligands/proteins have attracted a great deal of attention for drug delivery applications. This review covers recent advances in the development of SPIONs together...
Antibiotic-loaded chitosan–Laponite films for local drug delivery by titanium implants: cell proliferation and drug release studies
, Article Journal of Materials Science: Materials in Medicine ; Volume 26, Issue 12 , December , 2015 ; 09574530 (ISSN) ; Dehghani, M ; Simchi, A ; Sharif University of Technology
Kluwer Academic Publishers
2015
Abstract
Abstract: In this study, chitosan–Laponite nanocomposite coatings with bone regenerative potential and controlled drug-release capacity are prepared by electrophoretic deposition technique. The controlled release of a glycopeptide drug, i.e. vancomycin, is attained by the intercalation of the polymer and drug macromolecules into silicate galleries. Fourier-transform infrared spectrometry reveals electrostatic interactions between the charged structure of clay and the amine and hydroxyl groups of chitosan and vancomycin, leading to a complex positively-charged system with high electrophoretic mobility. By applying electric field the charged particles are deposited on the surface of titanium...
Fabrication and Characterization of a Drug Release System Based on Mesoporous Silica Nanoparticles for Hydrophobic Drugs
,
M.Sc. Thesis
Sharif University of Technology
;
Yaghmaei, Soheila
(Supervisor)
;
Arpanaei, Ayyoob
(Supervisor)
;
Morshedi, Dina
(Co-Advisor)
Abstract
This research aims to develop a drug delivery system based on mesoporous silica nanoparticles (MSNPs) for hydrophobic drugs and evaluating their cytotoxicity. The internal environment of the body is aqueous, while most of effective drugs display poor aqueous solubility, resulting in insufficient bioavailability. Due to their several unique properties, such as a large surface area, tunable pore size, facile surface multi functionalization and excellent biocompatibility, MSNPs are recognized as promising and powerful tools to overcome this hurdle. In the present study, MSNPs were synthesized using template removing method and then were functionalized through grafting procedure. They were...
The Effect of Protein Corona on Doxorubicin Release from the Magnetic Mesoporous Silica Nanoparticles and the Effect of Polyethylene Glycol Coating on drug Delivery System
, M.Sc. Thesis Sharif University of Technology ; Pourjavadi, Ali (Supervisor)
Abstract
The nanoparticles have been widely used in the field of physics, chemistry, electronics and mechanics because of their high surface area. One of their most important applications is in drug delivery systems as smart drug nanocarrier. Magnetic nanoparticles (including Fe2O3, Fe3O4) are the good candidates for this purpose. It is clear that, upon to entrance of nanoparticle into biological media (such as plasma), the surface of nanoparticles were covered by protein layers (protein corona). This layer is very stable and created new surface on the nanoparticles. The protein corona layer intracts with cellular receptors and determines the fate of nanoparticles. Protein corona covers the targeting...
Synthesis and characterization of semi-conductive nanocomposite based on hydrolyzed collagen and in vitro electrically controlled drug release study
, Article Polymer (United Kingdom) ; Volume 76 , October , 2015 , Pages 287-294 ; 00323861 (ISSN) ; Doroudian, M ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
In this study, a semi-conductive nanocomposite for electrically controlled drug delivery is introduced. Hydrolyzed collagen known as a naturally abundant polypeptide was modified with polycaprolactone. This modification changed the mechanical properties of the hydrolyzed-collagen. A hydrogel compound was synthesized through radical co-polymerization of acrylic acid on the backbone of this biocompatible polymer in the presence of a crosslinker. The reaction parameters affecting the water absorbency of the hydrogel were optimized using Taguchi method. In situ polymerization of aniline, incorporated conductive nanofiber pathways throughout the hydrogel matrix. 1H NMR, TGA, AFM, SEM, FTIR,...
Diffusional release of a dispersed solute from a cylindrical polymeric matrix into an infinite external volume
, Article Applied Mathematics and Computation ; Volume 259 , May , 2015 , Pages 676-685 ; 00963003 (ISSN) ; Abdekhodaie, M. J ; Sharif University of Technology
Elsevier Inc
2015
Abstract
Numerical and analytical exact solutions of diffusional release from a cylindrical polymeric matrix into an infinite medium have been developed in which the initial solute loading (A) is greater than solubility limit (Cs). Also, the effects of boundary layers on the drug release rate have been studied. The numerical solution is valid for any initial drug loading whereas analytical solution can be used for high values of drug loading. Comparisons have been made between numerical and analytical exact solutions in upper and lower bounds (A/Cs蠑1 and A/Cs→1) and previously presented approximate solution. The presented results validate the proposed numerical solution
The effect of protein corona on doxorubicin release from the magnetic mesoporous silica nanoparticles with polyethylene glycol coating
, Article Journal of Nanoparticle Research ; Volume 17, Issue 4 , April , 2015 ; 13880764 (ISSN) ; Tehrani, Z. M ; Mahmoudi, N ; Sharif University of Technology
Kluwer Academic Publishers
2015
Abstract
In the present work, biocompatible superparamagnetic iron oxide nanoparticles coated by mesoporous silica were used as drug nanocarriers for doxorubicin (Dox; an anticancer drug) delivery. In biological media, the interaction of protein corona layer with the surface of nanoparticles is inevitable. For this reason, we studied the effect of protein corona on drug release from magnetic mesoporous silica nanoparticles (MMSNs) in human plasma medium. Besides, we used hydrophilic and biocompatible polymer, polyethylene glycol (PEG), to decrease protein corona effects. The results showed the increased Dox release from PEGylated MMSNs compared with bare MMSNs. This result indicated that the coating...
Controlled release of doxorubicin from electrospun PEO/chitosan/graphene oxide nanocomposite nanofibrous scaffolds
, Article Materials Science and Engineering C ; Volume 48 , March , 2015 , Pages 384-390 ; 09284931 (ISSN) ; Aboutalebi Anaraki, N ; Irani, M ; Roshanfekr Rad, L ; Shamshiri, S ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
Polyethylene oxide (PEO)/chitosan (CS)/graphene oxide (GO) electrospun nanofibrous scaffolds were successfully developed via electrospinning process for controlled release of doxorubicin (DOX). The SEM analysis of nanofibrous scaffolds with different contents of GO (0.1, 0.2, 0.5 and 0.7 wt.%) indicated that the minimum diameter of nanofibers was found to be 85 nm for PEO/CS/GO 0.5% nanofibers. The π-π stacking interaction between DOX and GO with fine pores of nanofibrous scaffolds exhibited higher drug loading (98%) and controlled release of the DOX loaded PEO/CS/GO nanofibers. The results of DOX release from nanofibrous scaffolds at pH 5.3 and 7.4 indicated strong pH dependence. The...
Evaluation of Controlled Drug Release Chitosan-based Coatings on Titanium Implants: Microstructure, Bioactivity and Biocompatibility
, Ph.D. Dissertation Sharif University of Technology ; Simchi, Abdolreza (Supervisor)
Abstract
Implant-associated infections are one of the most serious complications in orthopaedic and trauma surgery as it may result in poor functional outcome, implant failure, chronic osteomyelitis or even death. Great concerns have been taken to reduce implant-associated infections through progressing in operating standards, minimizing the possibility of contamination during surgery, reducing the establishment of infection by perioperative antibiotic prophylaxis, and confining of pathogenic strains by patient isolation. In spite of these preventions, the percentage of postoperative infections is still rising. Composite coatings with bone-bioactivity and drug-eluting capacity are considered as...