用胭脂红酸极谱分析法测定人血清白蛋白的研究

在pH值为4.0的Britton-Robinson(B-R)缓冲溶液中,胭脂红酸在滴汞电极上-0.54V(vs.SCE)处有一个灵敏的极谱还原峰,加入人血清白蛋白(HSA)后,两者之间发生结合反应形成复合物,其还原峰电位不变,而还原峰电流明显下降。峰电流的降低与蛋白质浓度在一定范围内成正比,优化了结合反应条件和电化学测定条件,建立了测定血清白蛋白的电化学分析新方法,应用于人血清白蛋白的测定,线性范围为2.0～70.0mg·L-1。考察了共存物质的影响,并应用于人血清样品中蛋白质含量的测定,结果与传统的考马斯亮蓝G-250光度法一致。本方法简便、准确、灵敏,选择性和重复性好。

Determination of serum albumin with carminic acid by polarographic

In pH 4.0 Britton-Robinson (B-R) buffer solution carminic acid has a well-defined second order derivative linear sweep polarographic wave at -0.54 V(vs.SCE) and the addition of human serum albumin(HSA) to the carminic acid solution resulted in the decrease of the peak current without the change of peak potential, which indicates that they can interact with each other to form a supermolecular complex. The reaction conditions were optimized. Under the optimal conditions the decrease of the peak current was proportional to the concentration of proteins. Taking HSA as an example, the effects of some coexistent substances on the determination were studied. This new electrochemical method was further applied to the determination of total amounts of proteins in human serum samples with satisfactory results and the results agree with those of the routine spectrophotometric method of Coomassie brilliant blue G-250. So this new method is of highly selectivity, simplicity and repeatablility.