羧甲基壳聚糖-Cu(Ⅱ)配合物与牛血清白蛋白作用机理研究

Study on interaction mechanism of carboxymethyl chitosan-Cu(Ⅱ)complex with bovine serum albumin

用光谱学和电化学方法,研究了含不同Cu2+含量的羧甲基壳聚糖铜配合物(CMC-Cu)与牛血清白蛋白(BSA)之间的相互结合机理。通过荧光法确定了CMC-Cu对血清白蛋白的荧光猝灭机制为静态猝灭,计算出在室温下该结合反应的结合常数和结合位点数与配合物中Cu2+含量有关。紫外光谱显示,CMC-Cu的紫外光谱在加入BSA后表现减色效应和明显的蓝移,而BSA的紫外光谱在加入CMC-Cu后表现减色效应和明显的红移。电化学研究发现:CMC-Cu的氧化还原电流随着BSA的加入而明显降低,氧化还原峰电位差增大,表明BSA与血清白蛋白发生反应,生成比较稳定的复合物。以上结论证明CMC-Cu在体内能够被BSA存储和转运。

The interaction between carboxymethyl chitosan-copper complex with different Cu2＋amount and bovine serum albumin（ BSA） was studied by spectrum and cyclic voltammetry methods. Results showed that complex quenched the BSA fluorescence and it was static quenching,the binding constant and the number of binding sites were related to the content of Cu2＋. UV absorbance of complex decreased and the peaks had blue-shift after adding BSA,and the UV absorbance of BSA decreased and the peaks had redshift after adding complex,which indicated that there was a complex formed between complex and BSA; the redox current of complex decreases obviously and the redox peak potential difference increases adding BSA,which indicated that a reaction happend between complex and BSA,and generated more stable complexes.