Impact of Lactic Acid and Genipin Concentration on Physicochemical and Mechanical Properties of Chitosan Membranes

Chitosan is a linear polysaccharide that has a growing interest in several biomedical applications. Due to its poor solubility in water, aqueous organic acids are required to dissolve chitosan. Chitosan-based materials have been widely investigated for several industrial and biomedical applications. It becomes crucial to study the effect of the additives on the chemical, physical, and mechanical properties of chitosan. Here, we present the effect of various material combinations: chitosan, lactic acid and genipin. We intend to study the effect of elevated concentrations of lactic acid on the stability and elasticity of chitosan membranes. Our research also presents the effect of the concentration of genipin crosslinker, a biocompatible natural product, on the properties of chitosan materials. Obtained results show that lactic acid acts as a physical and a chemical crosslinker between chitosan chains, which leads to increase chitosan membrane stretchability thanks to the plasticizing characteristic of lactic acid. Obtained membranes show a high solubility in water that can be avoided by the introduction of genipin as a crosslinker. This significantly reduces the solubility of membranes in aqueous solutions and makes them more stable even under low pH's.