Spectroscopic Studies on Cu2+ and Ca2+ Binding with Glycosaminoglycans

[摘要] A general spectroscopic method is described for studies on the complex formation between metal ions and ligands, and is applied to Cu2+ and Ca2+ binding to glycosaminoglycans. The order of binding constants for both ions is heparin > dermatan sulfate > chondroitin sulfate. The electrostatic forces are shown to be the predominant factor in the interaction. The 2- to 3-fold higher affinity for Cu2+ than for Ca2+ is obtained for heparin and dermatan sulfate, but little difference for chondroitin sulfate. These results are explained as chelation of both carboxyl and sulfate groups to Cu2+ in former cases. The difference of binding constants among glycosaminoglycans is related to proposed various biological functions of the biopolymers.

[学科分类] 化学（综合）