Reaction of gelatin and chitosan with water soluble carbodiimides

Authors: Taylor, Maryann; Bumanlag, Lorelie; Latona, Nicholas - Nick; Brown, Eleanor - Ellie; Liu, Cheng Kung

Submitted to: Journal of American Leather Chemists Association
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/27/2016
Publication Date: 2/1/2017
Citation: Taylor, M.M., Bumanlag, L.P., Latona, N.P., Brown, E.M., Liu, C. 2017. Reaction of gelatin and chitosan with water soluble carbodiimides. Journal of American Leather Chemists Association. 112(2):52-58.

Interpretive Summary: The feasibility of using chemical and enzyme treatments on protein and carbohydrate waste products for the purpose of making products with unique functional properties has previously been demonstrated. In recent research, we investigated the widely reported 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) which has been used to crosslink proteins for purpose of making biomaterials. Both gelatin and chitosan had reactivity with EDC however when the gelatin and chitosan were reacted together in the presence of the carbodiimide (EDC), the physical properties (gel strength, melting point and viscosity) improved significantly over the protein and carbohydrate when they were reacted separately, resulting in unique products. In this continuing study, less expensive, commercially available, water-soluble and environmentally-safe multifunctional carbodiimides were reacted with gelatin, chitosan, and with mixtures of gelatin and chitosan for the purpose of making biopolymers. The physical properties and the molecular weight distribution of gel products will be reported, as well as results of analysis to investigate whether these reaction products fluoresce. Preliminary results indicate reactivity similar to use of EDC. These studies will lead to a better understanding of the reactivity of carbodiimides and the optimal conditions for developing appropriate products.

Technical Abstract: Earlier research from this laboratory has demonstrated the feasibility of using chemical and enzymatic treatments on protein and carbohydrate waste products for the purpose of making fillers to enhance the properties of leather. In our ongoing studies, we examined the reactivity of various concentrations of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) with gelatin, chitosan and combinations of both, and found that both gelatin and chitosan had reactivity with EDC. Moreover, when the gelatin and chitosan were reacted together in the presence of the carbodiimide, the physical properties improved significantly over those of the protein and carbohydrate when reacted separately. In this continuing study, less expensive, commercially available, water-soluble and environmentally-safe multifunctional carbodiimides were reacted with gelatin, chitosan and mixtures of gelatin and chitosan for the purpose of making biopolymers. The physical properties, molecular weight distribution of gel products will be reported, as well as epi-fluorescent imaging. Initial results indicate reactivity similar to EDC. These studies should lead to a better understanding of the reactivity of carbodiimide and optimal conditions for developing appropriate products.