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Preparation of ethyl cellulose microcapsules containing perphenazine and polymeric perphenazine based on acryloyl chloride for physical and chemical studies of drug release control [electronic resource]
, Article Polymer International ; Volume 47, Issue 4, pages 413–418, December 1998 ; Pourjavadi, A ; Hashemi, S. A ; Arabi. , H ; Sharif University of Technology
Abstract
The preparation of microcapsules containing perphenazine by solvent evaporation using ethyl cellulose is described. The microparticles are formed after solvent evaporation and polymer precipitation. The drug was dissolved in a polymer solution and emulsified into an aqueous phase to form microcapsules. To study the effects on particle size, encapsulation efficiency and morphology, three different molecular weights of ethyl cellulose (Mw=47000, 71000 and 99000) were used. Covalent bonding of drugs to polymers via hydrolytically or enzymatically cleavable covalent bond was achieved for sustained drug delivery. The release rate of perphenazine from these systems was investigated
Super-hydrophilic characteristic of thermochemically prepared CdS nanocrystals
, Article Physica E: Low-Dimensional Systems and Nanostructures ; Vol. 58 , April , 2014 , pp. 146-152 ; ISSN: 13869477 ; Taghavinia, N ; Babaei, A ; Sharif University of Technology
Abstract
CdS nanocrystals were thermochemically (thermally activated) synthesized thorough the reaction between CdSO4 and Na2S 2O3 in an aqueous solution. Thioglycolic Acid (TGA) was used as the capping agent and catalyst of the reaction. The method was based on heat activated dissociation of Na2S2O3 and controllable release of S and free electrons in the solution. CdS NCs were formed by heating the sample solution at 96 C for 1 h. The results of optical spectroscopy and transmission electron microscopy demonstrated round shape NCs with sizes about 3.0 nm. The nanocrystals were also luminescent and represented a broad emission with a peak located at 515 nm and FWHM of 160 nm. Several samples were...
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...
Modeling and comparison of different simulations for release of amoxicillin from chitosan hydrogels
, Article Polymer - Plastics Technology and Engineering ; Volume 52, Issue 11 , 2013 , Pages 1147-1153 ; 03602559 (ISSN) ; Ramazani S. A., A ; Shafiee, M ; Alemzadeh, I ; Ebrahimi, H ; Sharif University of Technology
2013
Abstract
In this research work, different devices made of glutaraldehyde cross-linked chitosan hydrogels loaded by amoxicillin, have been prepared using freeze-drying method. Effects of system parameters such as cross-linker concentration, pH, and gel structure on the morphology and release behavior of devices have been investigated using standard methods. Morphological studies were performed using SEM instrument and controlled releases are followed via spectrophotometeric method. Reaction of glutaraldehyde with chitosan has been studied using FTIR instrument. SEM micrographs have shown that with increasing cross-linker percentage in hydrogel, pore sizes increased where pore size distribution...
Preparation and evaluation of bioactive and compatible starch based superabsorbent for oral drug delivery systems
, Article Journal of Drug Delivery Science and Technology ; Volume 23, Issue 5 , 2013 , Pages 511-517 ; 17732247 (ISSN) ; Ebrahimi, A. A ; Barzegar, S ; Sharif University of Technology
2013
Abstract
Novel types of highly swelling hydrogels (superabsorbent) were prepared by grafting crosslinked poly acrylic acid-co-2-hydroxyethylmetacrylate (PAA-co-HEMA) chains onto starch through a free radical polymerization method. The effect of grafting variables (i.e., concentration of methylenebisacrylamide (MBA), acrylic acid/2-hydroxy methymetacrylate (AA/HEMA) weight ratio, ammonium persulfate (APS), starch, neutralization percent, were systematically optimized to achieve a hydrogel with a maximum swelling capacity. The superabsorbent (SAP) formation was confirmed by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The controlled-release behavior of...
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
Synthesis and characterization of a novel (salep phosphate)-based hydrogel as a carrier matrix for fertilizer release
, Article Reactive and Functional Polymers ; Volume 72, Issue 10 , 2012 , Pages 667-672 ; 13815148 (ISSN) ; Doulabi, M ; Soleyman, R ; Sharif, S ; Eghtesadi, S. A ; Sharif University of Technology
Elsevier
2012
Abstract
Salep phosphate modified biopolymers with different phosphate contents were prepared via reacting salep (a multi-component polysaccharide obtained from dried tubers of certain natural terrestrial orchids) with a solution of primary and secondary sodium phosphates under basic conditions in a semidry process. Structural characterization of salep phosphates were carried out by 31P NMR, FT-IR spectra and TGA curves. Determination of the phosphate content in samples was done by a standard spectrophotometric method. Then, novel (salep phosphate)-based hydrogels were synthesized by graft copolymerization of acrylic acid (AA) monomer onto salep phosphate backbones. Effect of the phosphate contents...
Chitosan-surface modified poly(lactide-co-glycolide) nanoparticles as an effective drug delivery system
, Article 2011 18th Iranian Conference of Biomedical Engineering, ICBME 2011, 14 December 2011 through 16 December 2011 ; December , 2011 , Pages 109-114 ; 9781467310055 (ISBN) ; Moztarzadeh, F ; Mozafari, M ; Asgari, S ; Shokri, S ; Alhosseini, S. N ; Sharif University of Technology
2011
Abstract
Since there have been many difficulties in clinical administration of anticancer drugs due to their poor solubility & targeting, development of new biodegradable Nano-carriers can provide good solutions to overcome the most of recent problems to obtain a better controlled release and targeted delivery of drugs with better efficiency and less side-effects. Acidic pH is regarded as a phenotypic characteristic of cancer tumors. Under this acidic condition, it is known that the surface charge of Chitosan-modified nano-particles become more positive. On the other hand, cancer cells are negatively charged. It is worth mentioning that by loading of anticancer drugs into this novel system, a strong...
Preparation of acrylated agarose-based hydrogels and investigation of their application as fertilizing systems
, Article Journal of Applied Polymer Science ; Volume 122, Issue 4 , November , 2011 , Pages 2424-2432 ; 00218995 (ISSN) ; Sadat Afjeh, S ; Seidi, F ; Salimi, H ; Sharif University of Technology
2011
Abstract
In this study, we attempt to synthesize novel acrylated agarose (ACAG)-based hydrogels with three different crosslinking densities. Acrylate groups were inserted onto agarose (AG) backbone through homogeneous reaction of acrylic monomers with AG backbone. Hydrogels were synthesized through radical copolymerization of a mixture of acrylic acid and 2-hydroxyethyl acrylate with ACAG in aqueous solution using ammonium persulfate as an initiator. Infrared spectroscopy (FTIR) was carried out to confirm the chemical structure of the hydrogel. Moreover, morphology of the samples was assessed by scanning electron microscopy. The equilibrium swelling capacities of synthesized hydrogels were evaluated...
UV-prepared salep-based nanoporous hydrogel for controlled release of tetracycline hydrochloride in colon
, Article Journal of Photochemistry and Photobiology B: Biology ; Volume 102, Issue 3 , March , 2011 , Pages 232-240 ; 10111344 (ISSN) ; Pourjavadi, A ; Ghavami, S ; Soleyman, R ; Jafarpour, F ; Sharif University of Technology
2011
Abstract
A highly swelling nanoporous hydrogel (NPH) was synthesized via UV-irradiation graft copolymerization of acrylic acid (AA) onto salep backbone and its application as a carrier matrix for colonic delivery of tetracycline hydrochloride (TH) was investigated. Optimized synthesis of the hydrogel was performed by the classic method. The swelling behavior of optimum hydrogel was measured in different media. The hydrogel formation was confirmed by Fourier transform infrared spectroscopy (FTIR) and thermo-gravimetric analysis (TGA/DTG/DTA). The study of the surface morphology of hydrogels using SEM showed a nanoporous (average pore size: about 350 nm) structure for the sample obtained under...
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...
Study and Preparation of Coated Drug by PEG Biopolymer (PEGylation) for Release Controlling
, M.Sc. Thesis Sharif University of Technology ; Vossoughi, Manoochehr (Supervisor) ; Sarbolouki, Mohammad Nabi (Supervisor)
Abstract
In the first part of this work, citric acid monomer was selected to produce dendrimer through the divergent method using logical conditions (for controlling its functional groups) on the base of poly (ethylene glycol) as the core. Triblock copolymers (ABA-type) of citric acid and poly (ethylene glycol) (PCA-PEG-PCA) as biocompatible compounds were synthesized in four different molecular weights and applied as nanocarriers. The structure definition of the molecules and nanoparticles were carried out using different spectroscopy methods. Diameter of the synthesized copolymers was investigated using dynamic light scattering (DLS) experiments and transmission electron microscopy (TEM) and it was...
Fabricate of Novel Drug Vector Based on Metallic Nanoparticles and Study of its Effects on Cell Line
, Ph.D. Dissertation Sharif University of Technology ; Vosoughi, Manouchehr (Supervisor) ; Alemzadeh, Iran (Supervisor)
Abstract
Application of nanoparticles in targeted delivery and controlled drug release is recently highly attracted especially in cancer therapy. In this study with the aim of developing a novel drug vector based on metallic nanoparticles, gold nanoparticles with their unique characteristics were used to design a vector for targeted anti-cancer drug delivery to tumor. First, gold nanoparticles were chemically synthesized therough sodium citrate and sodium brohydrate reductions with average diameters of 22 and 11 nm, respectively. Then, the activated poly ethylene glycol (PEG) and activated folic acid were conjugated to the lysine-capped gold nanoparticles. Subsequently, the widely used anticancer...
Fabrication and Characterization of PVA/PLA Composites
, M.Sc. Thesis Sharif University of Technology ; Frounchi, Masoud (Supervisor) ; Dadbin, Susan (Supervisor)
Abstract
Poly (vinyl alcohol) (PVA) hydrogel is a biocompatible material, which has been widely applied in drug delivery applications. Microspheres, nanospheres, and other types of particle-based drug delivery vehicles have proven capacity for long-term release. There is growing interest to overcoming the inherent pharmacological limitations of hydrogels by formulating particulate systems into the hydrogel matrix to form new delivery platforms. We here describe a simple composite system based on poly (vinyl alcohol) (PVA) hydrogels containing entrapped drug-loaded poly (lactic acid) (PLA) microspheres for controlled delivery over extended period of time. Gamma-Irradiation and freeze-thawing was...
Magnetic Nanocomposites Based on Bio-Degradable Polylactic Acid
, M.Sc. Thesis Sharif University of Technology ; Frounchi, Masoud (Supervisor)
Abstract
In this work, magnetite (Fe3O4) nanoparticles with an average siz21.9nm
modified by oleic acid were prepared by the coprecipitation method, which can linked well with organic molecules because of the presence of C-O-C on their surface. Then magnetic poly(lactic acid) (PLA)/ poly(ethylene glycol) (PEG) microspheres were prepared by the single emulsion solvent evaporation technology. The incorporation of magnetit nanoparticles and dox into the PLA matrix was confirmed by FTIR. XRD and VSM confirmed the existence of MNPs in the microspheres which maintained superparamagnetic behavior with a saturation magnetization of 50.69 emu/g.Electron microscopy SEM showed that the magnetic microspheres...
modified by oleic acid were prepared by the coprecipitation method, which can linked well with organic molecules because of the presence of C-O-C on their surface. Then magnetic poly(lactic acid) (PLA)/ poly(ethylene glycol) (PEG) microspheres were prepared by the single emulsion solvent evaporation technology. The incorporation of magnetit nanoparticles and dox into the PLA matrix was confirmed by FTIR. XRD and VSM confirmed the existence of MNPs in the microspheres which maintained superparamagnetic behavior with a saturation magnetization of 50.69 emu/g.Electron microscopy SEM showed that the magnetic microspheres...
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
Dendritic magnetite decorated by pH-responsive PEGylated starch: A smart multifunctional nanocarrier for the triggered release of anti-cancer drugs
, Article RSC Advances ; Volume 5, Issue 60 , Jun , 2015 , Pages 48586-48595 ; 20462069 (ISSN) ; Mazaheri Tehrani, Z ; Hosseini, S. H ; Sharif University of Technology
Royal Society of Chemistry
2015
Abstract
In the present study, we designed a pH-responsive drug nanocarrier based on polyamidoamine-modified Fe3 O4 nanoparticles coated by PEGylated starch-co-poly(acrylic acid). This carrier was used for the controlled release of doxorubicin as an anticancer drug model. The purpose of using the polyethylene glycol moiety is to generate a biostable nanocarrier in blood stream as it has been reported widely in the pharmaceutical literature. The use of a poly(acrylic acid) segment also provided pH-sensitivity to the polymer. Besides, the magnetic nanoparticles facilitate the cancer cell targeting with an external magnetic field located near the tumor site. This carrier was...
Alginate-based biodegradable superabsorbents as candidates for diclofenac sodium delivery systems
, Article Journal of Applied Polymer Science ; Volume 118, Issue 4 , 2010 , Pages 2015-2023 ; 00218995 (ISSN) ; Zeidabadi, F ; Barzegar, Sh ; Sharif University of Technology
2010
Abstract
Novel types of highly swelling hydrogels were prepared by grafting crosslinked polyacrylamide-co-poly-2-acrylamido-2-methylpropane sulfonic acid (PAAm-co-PAMPS) chains onto sodium alginate (Na-Alg) through a free radical polymerization method. The superabsorbent formation was confirmed by Fourier transform infrared spectroscopic (FTIR). The controlled release behavior of diclofenac sodium (DS) from superabsorbent polymer was factinvestigated, and shown that the release profiles of DS from superabsorbent polymer were slow in simulated gastric fluid (SGF, pH 1.2) over 3 h, but nearly all of the initial drug content was released in simulated intestinal fluid (SIF, pH 7.4) within 21 h after...
Synthesis of folate-modified, polyethylene glycol-functionalized gold nanoparticles for targeted drug delivery
, Article Journal of Dispersion Science and Technology ; Volume 31, Issue 4 , 2010 , Pages 492-500 ; 01932691 (ISSN) ; Vosoughi, M ; Alamzadeh, I ; Tavakoli, A ; Sharif University of Technology
Abstract
The chemical synthesis and in vitro drug delivery response of folate-modified, polyethylene glycol-functionalized gold nanoparticles were studied. Lysine-capped gold nanoparticles were first prepared. Subsequently, the widely used anticancer agent doxorubicin (DOX) was successfully attached to the surface of folate-modified, polyethylene glycol-functionalized gold nanoparticles. Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM) were used to confirm the functionalization and conjugation steps in the chemical synthesis. The DOX-loading efficiency determined by UV-vis spectrometer was 80%. Drug release experiments displayed a controlled-release behavior...
Folate-receptor-targeted delivery of doxorubicin using polyethylene glycol-functionalized gold nanoparticles
, Article Industrial and Engineering Chemistry Research ; Volume 49, Issue 4 , 2010 , Pages 1958-1963 ; 08885885 (ISSN) ; Vossoughi, M ; Alemzadeh, I ; Sharif University of Technology
Abstract
Doxorubicin-loaded nanocarriers were produced employing folate-modified polyethylene glycol (PEG)-functionalized gold nanoparticles for targeted delivery to positive folate-receptor cancer cells. Doxorubicin and folate were, respectively, conjugated to activated-folate and activated-PEG. The conjugates formed doxorubicin nanocarrier with an average size of 12 nm in diameter. The drug release response of functionalized gold nanoparticles was characterized by an initial rapid drug release followed by a controlled release. The doxorubicin nanocarriers showed higher cytotoxic effect on folate-receptor-positive cells (KB cells) than folatereceptor-negative cells (A549 cells). Cell viability in...