Ionically Crosslinked Thermoresponsive Chitosan Hydrogels formed In Situ: A Conceptual Basis for Deeper Understanding

Abstract

In situ formation and the performance of ionically crosslinked thermosensitive chitosan‐based hydrogels are presented. Experimental analyses, together with mechanistic descriptions of the events during hydrolysis, are employed to uncover the role of urea and isobutanol as chemical modifiers by comparing three classes of hydrogels formed in chitosan/β‐glycerolphosphate (β‐GP) solutions. Rheological measurements demonstrate that urea caused an increase in gelation time and temperature of chitosan/β‐GP systems, while isobutanol has an inverse effect. Interpretations based on increase in pH and chemical bonding of components in chitosan solutions provide further insight into hydrogel network formation. Urea can hinder the hydrophobic characteristics of chitosan‐based hydrogels, whereas isobutanol has the opposite effect. The shape retaining strategy applied here helps in simulation and interpretation of performance of thermosensitive hydrogels for biomedical purposes.

The Taste of Waste: The Edge of Eggshell Over Calcium Carbonate in Acrylonitrile Butadiene Rubber

“…Nowadays, disposal of polymer wastes in landfills is a serious challenge in the developing countries, for disposed polymer wastes are permanent contaminants to the local environment including soil and water. This underlines the need for the development of biodegradable polymer composites [1][2][3][4][5]. On the other hand, the competitive market demands a delicate balance between the cost and the performance of the new products.…”

The Tunable Porous Structure of Gelatin–Bioglass Nanocomposite Scaffolds for Bone Tissue Engineering Applications: Physicochemical, Mechanical, and In Vitro Properties

“…Polymers are one of the most common materials that have been used for fabrication of tissue engineering scaffolds. Natural polymers (collagen, gelatin, chitosan, etc.) have shown more similarity to the composition of the body following better interaction with cells .…”

Tuning the Mechanical Properties of Multiarm RAFT-Based Block Copolyelectrolyte Hydrogels via Ionic Cross-Linking for 3D Cell Cultures

“…Chitosan is another example of a natural ionic hydrogel system. Chitosan is a cationic polysaccharide derived from the exoskeleton of prawns and other crustaceans. , Kim et al and Moura et al have reported chitosan ionically cross-linking with multivalent anions such as PO 3– ions, in particular, β-glycerolphosphate, to yield highly biocompatible hydrogels. , …”