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Chitosan Chloride (chitosan + chloride)
Selected AbstractsTransmission electron microscopy and electron diffraction study of BSA-loaded quaternized chitosan nanoparticlesJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2008A-jun Wan Abstract Chitosan nanoparticles, O -(2-hydroxyl) propyl-3-trimethyl ammonium chitosan chloride (O -HTCC) nanoparticles and bovine serum albumin (BSA) loaded chitosan and O -HTCC nanoparticles of a size (about 200,600 nm) were obtained through the process of ionic gelation between chitosan or O -HTCC and sodium tripolyphosphate (TPP). The physicochemical properties of nanoparticles made from chitosan, O -HTCC, BSA loaded chitosan, and BSA loaded O -HTCC were determined by transmission electron microscopy (TEM), polarized optical microscopy (POM), photon correlation spectroscopy (PCS), and X-ray diffraction (XRD) pattern. Zeta potential was also performed to understand the surface properties of nanoparticles and their ability to bind negatively charged BSA. TEM, POM, and XRD suggested that ionic-gelation process significantly influenced the crystallinity of BSA, and greater chain realignment in the BSA-loaded chitosan and O -HTCC nanoparticles. PCS revealed that BSA-loaded chitosan nanoparticles were bigger than chitosan nanoparticles in size and BSA-loaded O -HTCC nanoparticles were smaller than O-HTCC nanoparticles in size. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008 [source] Chitosan-coated antifungal formulations for nebulisationJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 7 2010Yacoub Y. Albasarah Abstract Objectives, The aim of this study was to produce and characterise amphotericin B (AmB) containing chitosan-coated liposomes, and to determine their delivery from an air-jet nebuliser. Methods, Soya phosphatidylcholine : AmB (100 : 1) multilamellar vesicles were generated by dispersing ethanol-based proliposomes with 0.9% sodium chloride or different concentrations of chitosan chloride. These liposomes were compared with vesicles produced by the film hydration method and micelles. AmB loading, particle size, zeta potential and antifungal activity were determined for formulations, which were delivered into a two-stage impinger using a jet nebuliser. Key findings, AmB incorporation was highest for liposomes produced from proliposomes and was greatest (approximately 80% loading) in chitosan-coated formulations. Following nebulisation, approximately 60% of the AmB was deposited in the lower stage of the two-stage impinger for liposomal formulations, for which the mean liposome size was reduced. Although AmB loading in deoxycholate micellar formulations was high (99%), a smaller dose of AmB was delivered to the lower stage of the two-stage impinger compared to chitosan-coated liposomes generated from proliposomes. Chitosan-coated and uncoated liposomes loaded with AmB had antifungal activities against Candida albicans and C. tropicalis similar to AmB deoxycholate micelles, with a minimum inhibitory concentration of 0.5 µg/ml. Conclusions, This study has demonstrated that chitosan-coated liposomes, prepared by an ethanol-based proliposome method, are a promising carrier system for the delivery of AmB using an air-jet nebuliser, having a high drug-loading that is likely to be effectively delivered to the peripheral airways for the treatment of pulmonary fungal infections. [source] Potential prospects of chitosan derivative trimethyl chitosan chloride (TMC) as a polymeric absorption enhancer: synthesis, characterization and applicationsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 9 2008Jasjeet K. Sahni ABSTRACT In recent years, researchers have been working extensively on various novel properties of polymers to develop increased efficiency of drug delivery and improve bioavailability of various drug molecules, especially macromolecules. Chitosan, a naturally occurring polysaccharide, because of its protonated/polymeric nature, provides effective and safe absorption of peptide and protein drugs. Its transmucosal absorption is, however, limited to acidic media because of its strong intermolecular hydrogen bonds. A new partially quaternized chitosan derivative, N-trimethyl chitosan chloride (TMC), has been synthesized with improved solubility, safety and effectiveness as an absorption enhancer at neutral pH and in aqueous environment. It enhances the absorption, especially of peptide drugs, by reversible opening of tight junctions in between epithelial cells, thereby facilitating the paracellular diffusion of peptide drugs. This derivative thus opens new perspectives as a biomaterial for various pharmaceutical applications/drug delivery systems. This review deals with the potential use of the quaternized chitosan derivative as a permeation enhancer for the mucosal delivery of macromolecular drugs along with its other biomedical applications. [source] Alginate,chitosan complex coacervation for cell encapsulation: Effect on mechanical properties and on long-term viabilityBIOPOLYMERS, Issue 6 2006Limor Baruch Abstract The use of chitosan in complexation with alginate appears to be a promising strategy for cell microencapsulation, due to the biocompatibility of both polymers and the high mechanical properties attributed by the use of chitosan. The present work focuses on the optimization and characterization of the alginate,chitosan system to achieve long-term cell encapsulation. Microcapsules were prepared from four types of chitosan using one- and two-stage encapsulation procedures. The effect of reaction time and pH on long-term cell viability and mechanical properties of the microcapsules was evaluated. Using the single-stage encapsulation procedure led to increase of at least fourfold in viability compared with the two-stage procedure. Among the four types of chitosan, the use of high molecular weight (MW) chitosan glutamate and low MW chitosan chloride provided high viability levels as well as good mechanical properties, i.e., more than 93% intact capsules. The high viability levels were found to be independent of the reaction conditions when using high MW chitosan. However, when using low MW chitosan, better viability levels (195%) were obtained when using a pH of 6 and a reaction time of 30 min. An alginate,chitosan cell encapsulation system was devised to achieve high cell viability levels as well as to improve mechanical properties, thus holding great potential for future clinical application. © 2006 Wiley Periodicals, Inc. Biopolymers 82:570,579, 2006 This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com [source] Application of a fibre-reactive chitosan derivative to cotton fabric as a zero-salt dyeing auxiliaryCOLORATION TECHNOLOGY, Issue 3 2004Sang-Hoon Lim Cotton fabric has been treated with a fibre-reactive chitosan derivative containing quaternary ammonium groups, O -acrylamidomethyl- N -[(2-hydroxy-3-trimethylammonium)propyl]chitosan chloride (NMA-HTCC). Cotton treated with NMA-HTCC has been dyed with direct and reactive dyes without the addition of salt. The colour yield was higher than that on untreated cotton, despite the addition of a large amount salt in the latter case. After dyeing, cotton treated with NMA-HTCC gave better wash fastness than the untreated cotton. The light fastness was however inferior to that on untreated cotton. The antimicrobial activity of cotton treated with NMA-HTCC against Staphylococcus aureus was considerably lower after dyeing, probably due to the antimicrobial effect of the cationic group on NMA-HTCC being blocked by its combination with the anionic dye. [source] | ||||||||||