Preparation of Coordination Compound of Carboxymethyl

Carboxymethyl chitooligosaccharidesGd(Ⅲ) coordination compound(CM-COS-Gd) was synthesized by reaction of carboxymethyl chitooligosaccharides with Gd(NO3)3 and characterized by IR spectroscopy 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.