Abstract: Objective: To design and synthesize dialdoxylose, a glutaraldehyde analogue which is expected to have a low toxicity, and to characterize its performance in crosslinking chitosan in 1% acetic acid solution. Methods: Dialdoxylose was obtained by sodium periodate oxidation and deprotection of monoacetone glucose and used to form crosslinked chitosan gels. The gel strength, fluid properties, water activity and thermal stability of chitosan gels were analyzed by texture profile analysis (TPA), low field-nuclear magnetic resonance (NMR) spectroscopy and differential scanning calorimetry (DSC). Results: It was found that dialdoxylose exhibited two structures in water, (α,β) and (β,β), with a ratio of 44.4:65.6. The hardness, viscosity and water-holding capacity of the chitosan gel crosslinked with 0.002 g/mL dialdoxylose were highest. Conclusion: Dialdoxylose has an obvious crosslinking effect on chitosan, which is greatly affected by its concentration. The results of this study are of theoretical guiding significance for the development of new low-toxicity small-molecule crosslinking agents.

Key words: crosslinking; chitosan; gel; dialdoxylose