铬天青S-Cu(Ⅱ)配合物探针吸光光度法测定蛋白质的研究

Study on spectrophotometric determination of proteins by using chrome azurol SCu(Ⅱ) complex as spectral probe

在pH 5.0 B-R缓冲介质中,蛋白质与铬天青S-Cu（Ⅱ）配合物发生结合反应形成超分子复合物,使体系的最大吸收波长红移了30 nm,由此提出了普通光度法测定蛋白质（BSA）的新方法。最佳条件下,该复合物的最大吸收波长位于620 nm处,表观摩尔吸光系数ε=6.13×105L.mol-1.cm-1,蛋白质（BSA）量在10-60μg/mL范围内遵循比耳定律。方法可直接用于蛋清中蛋白质的测定,回收率为100%-105%。

A new mothod for the determination of proteins by using chrome azurol S-Cu（ Ⅱ ） complex as spectral probe has been established. It is based on the binding interaction of protein with chrome azurol S-Cu（ Ⅱ ） complex in Briton- Robinson buffer at pH 5.0. The binding interaction produces supermolecular complex chrome azurol S-Cu（ Ⅱ ）-BSA with its maximum absorption at 620 nm. The apparent molar absorptivity of this complex is 6.13 × 10^5 L. mol^-1. cm^-1 Beer＇s law is obeyed in the range of 10 - 60 μg/mL for BSA. The method has been applied to the direct determination of proteins in the egg albumin with the recoveries of 100% - 105%.