羧甲基壳寡糖与钆配合物的制备

Preparation of Coordination Compound of Carboxymethyl Chitooligosaccharides and Gadolinium Nitroxide

用羧甲基壳寡糖(CM-COS)与硝酸钆反应,制备了羧甲基壳寡糖与钆的配合物(CM-COS-Gd)。用红外光谱、热重分析等测试手段对配合物进行了表征。讨论了溶液的酸碱度、反应时间和物料比对配合物形成的影响,对CM-COS-Gd的配位机理进行了初步研究。结果表明,不仅CM-COS中的羧基参与了配位,氨基上的氮原子和羟基氧原子也参与了配位。CM-COS-Gd和CM-COS相比,热稳定性有所增加。

Carboxymethyl chitooligosaccharides-Gd（Ⅲ ） coordination compound（CM-COS-Gd） was syn- thesized by reaction of carboxymethyl chitooligosaccharides with Gd（NO3 ）3 and characterized by IR spec- troscopy and thermogravimetric analyses （TGA）. The effects of pH, reaction time and Gd（NO3）3 dose on the formation of coordination compound were investigated, and the coordination mechanism was also studied. Results showed that Gd（ Ⅲ） was coordinated with -NH2, -OH, -COOH of carboxymethyl chitooligosaccharides. Compared with carboxymethyl chitooligosaccharides, the thermostability of carboxymethyl chitooligosaccharides-Gd（ Ⅲ ） coordination compound was high.