Glutaraldehyde-crosslinked O-carboxymethyl chitosan-gum Arabic coacervates: Characteristics versus complexation acidity

Glutaraldehyde-crosslinked O-carboxymethyl chitosan (O-CMC)-gum Arabic (GA) coacervates were characterized against coacervation acidity. As the coacervation pH increased from 3.0 to 6.0, the crosslinking degree of the coacervates and its sensitivity to glutaraldehyde concentration variation declined gradually, but the elasticity increased markedly. Crosslinking improved the structure compactness and thermal stability of the coacervates and high coacervation pH favored the increase of the two parameters, but a reverse trend was observed regarding swelling ratio in the simulated gastric fluid. It was concluded that glutaraldehyde-crosslinked O-CMC-GA coacervates with required properties could be tailored by selecting an appropriate complexation acidity.