壳聚糖仿生黏合剂的一步原位制备及性能研究

One-Step in situ Preparation and Properties of Chitosan-Based Bioadhesive

邻苯二酚可赋予组织黏合剂优异的耐湿黏附能力。利用一步原位法,仅需壳聚糖(CS)的Fe^(3+)溶液与3,4-二羟基苯甲醛(DBA)溶液的机械混合,通过CS与DBA之间的席夫碱反应、Fe^(3+)与DBA之间的氧化配位作用,即可实现黏合剂的快速制备。所得黏合剂表现出可控的成胶时间、黏合强度、流变性质以及优异的表面适应性与稳定性。较传统的席夫碱-还原法,一步原位法可获得更优异的黏合强度(48.8 kPa),且制备时长缩短至几分钟,为新型黏合剂的快速制备提供了重要途径。

In this paper,through the novel one-step strategy,once mechanical mixing between chitosan polymer(dissolved in Fe^(3+)solution with predetermined concentration,termed as CS-Fe)and 3,4-dihydroxybenzaldehyde(DBA)solution was completed,a brown hydrogel(termed as CS-DBA-Fe)could be instantly prepared in situ as results of Schiff base reaction between CS and DBA,plus oxidation-coordination interaction between Fe^(3+)and catechol groups.Multiple interactions,including coordination bond,covalent bond,hydrogen bond,π-πandπ-cation interaction inside the CS-DBA-Fe crosslinking system were achieved simultaneously,leading to drastic versatile adhesion.What’s more,the obtained hydrogels also exhibited various merits,including tunable gelation time,adhesion strength and rheological properties,as well as outstanding surface adaptability and stability,rendering it a promising candidate of tissue adhesion materials for emergent situation.Lastly,though several traditional methods like reductive amination strategy(RA strategy)were developed,they usually involve prolonged reaction time,harsh reaction conditions and complicated purifying procedures.Herein,hydrogels prepared by RA strategy(termed as CCS-Fe)were used as the benchmark to further evaluate the adhesion strength of CS-DBA-Fe adhesives.Compared with the RA strategy,adhesives obtained by this method not only had better bonding strength(up to 48.8 kPa),and the preparation time was greatly shortened(from 72 h to less than 10 min).The one-step in-situ preparation of tissue adhesive provides an important alternative for the facile preparation of biomimetic tissue adhesives.