Could glutaric acid (GA) replace glutaraldehyde in the preparation of biocompatible biopolymers with high mechanical and thermal properties?

In the field of natural and/or synthetic polymer preparation and stabilization, glutaraldehyde is the most commonly used cross-linker. Glutaraldehyde is focused by several scientists due its ease of cross-linking ability through the formation of Schiff base type of compound. Though glutaraldehyde cross-linked product has several advantages, the main drawback lies with the toxicity and poor mechanical stability. The poor mechanical strength of glutaraldehyde cross-linked product is due to the bonding pattern (-C=N-) between glutaraldehyde and amine group containing compound, where, there is a large energy barrier to rotation associated with groups joined by double bond. This is the time to search for an alternative cross-linker which will provide a non-toxic and mechanically stable biopolymer material. In order to achieve the requisite property, in the present study, we have chosen glutaric acid (oxidized form of glutaraldehyde) and studied its interaction with chitosan and type-I collagen. The chemistry behind the interaction and the characteristics of the biopolymer material obtained upon cross-linking suggests that non-covalent interactions play a major role in deciding the property of the said materials and its suitability for biomedical applications.