Chitosan and poly(vinyl alcohol) (PVA) were used to form a semi-interpenetrating polymeric network with glutaraldehyde as the cross-linker. The molecular weight and degree of deacetylation of the chitosan were 612 kDa and 72 %, respectively. The chemical bonds formed by the cross-linking reaction and transition of these bonds in different pH media were investigated. The gelation property of the...

We investigated the effect of sustained release of bone morphogenetic protein-2 (BMP-2) from an injectable chitosan gel on osteoblastic differentiation in vitro. We first characterized the release profile of BMP-2 from the gels, and then examined the cellular responses of preosteoblast mouse stromal cells (W-20-17) and human embryonic palatal mesenchymal (HEPM) cells to BMP-2. The release profi...

Nanospheres are being developed for the oral delivery of peptide-based drugs such as insulin. Mucoadhesive, biodegradable, biocompatible, and acid-protective biomaterials are described using a combination of natural polyelectrolytes, with particles formulated through nanoemulsion dispersion followed by triggered in situ gel complexation. Biomaterials meeting these criteria include alginate, dex...

Some physical properties of nanogel particles formed by chitosan ionically cross-linked by tripolyphosphate (TPP) have been studied. Electrokinetic properties and colloidal stability were analyzed as a function of pH and ionic strength of the medium. Chitosan particles showed volume phase transitions (swelling/shrinking processes) when the physicochemical conditions of the medium were changed. ...

Reactive Red 120 was utilized as an affinity dye-ligand to modify the surface of magnetic chitosan microspheres to improve the adsorption capacity for lysozyme. The impact of pH, ionic strength, adsorption time and initial lysozyme concentration on the adsorption of lysozyme from aqueous solutions was investigated. An increased adsorption amount of 116.9 mg/g lysozyme on Reactive Red 120 modifi...

Despite numerous scientific efforts many challenges need to be overcome in the ocular delivery because eyes have special and complex anatomic structures. The main problem with the conventional dosage forms is poor ocular bioavailability due to minimum ocular residence time, because of various anatomical and pathophysiological barriers prevailing in the eye. For this reason, much effort has been...

The goal of the present work was to study the influence of the swelling of chitosan derivatives on the enantioseparation and the separation performance recovery of chiral stationary phases (CSPs) based on these derivatives. Therefore, six chitosan bis(phenylcarbamate)-(n-octyl urea)s were synthesized, which were coated on macroporous 3-aminopropyl silica gel affording new CSPs. Most of the CSPs...

The goal of the present work was to study the influence of the swelling of chitosan derivatives on the enantioseparation and the separation performance recovery of chiral stationary phases (CSPs) based on these derivatives. Therefore, six chitosan bis(phenylcarbamate)-(n-octyl urea)s were synthesized, which were coated on macroporous 3-aminopropyl silica gel affording new CSPs. Most of the CSPs...

Chitosan, a naturally occurring polysaccharide derived from chitin, has been widely applied in drug delivery, tissue regeneration, wound healing, blood coagulation and immunostimulation due to its well-known biocompatibility and biodegradability. Additionally, because of its unique cationic nature and the gel/film/matrix forming capabilities, chitosan has been considered as a promising material...