【摘要】 苯硼酸(PBA)在水溶液中可与顺-1,2-二醇或1,3-二醇形成可逆共价键,常在纳米/水凝胶中用作葡萄糖响应单元或动态交联基团.本文提供了一种快速合成苯硼酸接枝壳聚糖衍生物(CPBA-HPCS)的方法.以羟丙基壳聚糖(HPCS)为原料, 2-(7-偶氮苯并三氮唑)-N,N,N’,N’-四甲基脲六氟磷酸酯(HATU)为缩合剂,在二甲基亚砜(DMSO)中反应1 h即可得到在pH>8.5的水溶液中可溶的CPBA-HPCS.采用傅里叶变换红外光谱(FTIR)和核磁共振波谱(NMR)对该衍生物结构进行验证,并对反应动力学进行了研究,得到了一系列不同取代度的CPBAHPCS,其取代度最高可达0.78.这种新的壳聚糖衍生物在制备智能水凝胶和药物载体方面具有较好的应用前景.更多还原

【Abstract】 Phenylboronic acid(PBA) can form reversible covalent bonds with cis-1,2-diol or 1,3-diol in an aqueous solution, which makes it useful as the glucose-responsive units or dynamic cross-linking groups in nano/hydrogels. In this paper, PBA was efficiently grafted on hydroxypropyl chitosan(HPCS) by employing 2-(7-azabenzotriazol-1-yl)-N,N,N’,N’-tetramethyluronium hexafluorophosphate(HATU) as a coupling reagent in dimethyl sulfoxide(DMSO).The resulting carboxyphenylboronic acid-grafted hydroxypropyl chitosan(CPBA-HPCS) was soluble when pH>8.5, and the structure was characterized and confirmed by Fourier-transform infrared spectroscopy(FTIR) and nuclear magnetic resonance(NMR). In addition, the kinetics of the reaction were studied and a series of CPBA-HPCS with different substitution degrees(up to 0.78) was prepared. This novel chitosan derivative has good application prospects in the preparation of smart hydrogels and drug carriers.更多还原