Degradation of chitosan and chemically modified chitosan by viscosity measurements

Abstract

Chitosan and chitosan-grafted-acrylamide were subjected to degradation in the presence and absence of a degrading agent at 378C by measuring the viscosity of polymer solutions. Extracts from the fresh rat droppings were used as the degrading agent to simulate the environmental degrading conditions. Results of this study indicated that the concentrations of acetic acid in solution and chemical modifications of chitosan affected the degradation both in the presence as well as in the absence of a degrading agent. Reduction in viscosity was used to study the degradation. Chitosan was stable up to sixteen days of immersion in acetic acid without the degrading agent, but it readily underwent degradation in the presence of a degrading agent. Chitosan-grafted-acrylamide also followed the same trend, but the extent of reduction in viscosity was much less than pure chitosan, indicating that the chemical modification has improved the stability of the polymer.

Freeze-casting porous chitosan ureteral stents for improved drainage

“…Chitosan is the material of choice for this first exploration of a freeze-cast, porous stent design because it offers additional parameters for the custom-design of scaffold properties: such as the molecular weight and degree of deacetylation. [48][49][50][51][52][53][54] Another advantage is that it is a naturally antimicrobial [55,56] and biodegradable [57][58][59] material, properties that reduce and possibly prevent biofilm formation, preventing stone formation by surface degradation, enable controlled drug release and enhance penetration, [60][61][62][63][64][65] and the selfremoval of the stent [66][67][68].…”

Near-Infrared Fluorescence Imaging for Noninvasive Trafficking of Scaffold Degradation

“…The implanted scaffolds are eventually degraded and replaced by vascularized tissues over time, and the rate of scaffold degradation and tissue formation inside the scaffold must be equivalent for successful outcomes45. Many efforts have focused on monitoring scaffold degradation behaviors by measuring changes in mechanical properties67, and molecular weight68, matrix weight9, morphology6, viscosity10; however, most of these methods require sacrifice of numerous animals at various time points, which often leads to inaccurate conclusions, as there can be broad batch-to-batch and animal-to-animal variations.…”

Development of a Cross-Linked Polysaccharide ofLigusticum wallichii– Squid Skin Collagen Scaffold Fabrication and Property Studies for Tissue-Engineering Applications

“…7 Ligusticum wallichii polysaccharide could improve degradation of the composite scaffold, high degree of covalent crosslinking enhanced stability of the network in scaffolds. [46].…”