以溴甲酚紫为电化学探针测定血清白蛋白

常见的蛋白质定量分析方法、电化学行为及其分析应用已有报道．本文基于酸性条件下蛋白质可与溴甲酚紫(BP)结合生成一种超分子复合物，使溴甲酚紫还原峰电流降低，建立了一种测定蛋白质的新方法，并用于测定人血清样品中的白蛋白含量．

Determination of Serum Albumin Using Bromocresol Purple as Electrochemical Probe

An electrochemical quantitative method of protein is developed based on the interaction between bromocresol purple(BP) and proteins. In pH 4.5 Britton-Robinson(B-R) buffer solution,BP has a sensitive reductive peak at -0.518 V( vs. SCE) on the hanging mercury drop electrode. After adding human serum albumin(HSA) to the above solution,the reduction peak current of BP decreased apparently without the shift of the peak potential. The decrease of the reductive peak current of BP is proportional to HSA concentration in the range of 1.0—20.0 mg/L and 20.0—200.0 mg/L with the regression equation ΔI″p=90.87+150.53 c(r =0.997) and ΔI″p=3 063.70+9.05 c(r =0.992),respectively. The binding ratio of HSA with BP is 1:2 and the binding constant βs=1.32×109. The proposed method was applied to determine the content of HSA in blood samples and the results are in accordance with the traditional Coomassie Brilliant Blue G-250 spectrophotometric assay. This method was further applied to the determination of bovine serum albumin,bovine hemoglobin,egg albumin etc. with satisfactory results.