茜素红与蛋白质分子Langmuir吸附聚集反应研究

Langmuir aggregation of alizarin red in protein macromolecule

在pH4.3的B-R缓冲体系中,用微相吸附-光谱修正技术[1]研究了茜素红(ARS)与牛血清白蛋白(BSA)、人血清白蛋白(HSA)的结合反应。其吸附结合常数分别为:KBSA-ARS=3.950×104,KHSA-ARS=4.377×104。染料与蛋白的最大结合数分别为NARS∶NBSA=9∶1,NARS∶NHSA=7∶1。经光谱修正技术计算结合产物的实际摩尔吸光系数分别为εBSA-ARS(537nm)=2.517×104L.mol-1.cm-1,εHSA-ARS(519nm)=2.051×104L.mol-1.cm-1,检出限BSA为19mg/L,HSA为23mg/L。经探讨该结合反应机理符合Langmuir吸附聚集反应方程。

The microphase adsorption-spectral correction （MPASC） technique is described and applied to the study on the interaction of Alizarin red （ARS） with two proteins： bovine serum albumin （BSA） and human serum albumin （HSA） at pH 4.3 Britton-Robinson buffer solution. The results show that the adsorption ratios of ARS to proteins are NARS ： NRSA = 9 ： 1, NARS ： NHAS = 7 ： 1, the adsorption constants are KARS-BSA = 3 . 346 ×10^4, KARS-HAS = 4. 483 ×10^4 respectively and the real molar absorptivities are measured to be εBSA-ARS（537 am） = 2.517 ×10^4L/（mol·cm）, εBSA-ARS （519 nm）= 2.051 ×10^4L/（mol·cm）. The detection limits are 19 mg/L for BSA, and 23 mg/L for HSA. The aggregation of ARS in protein has been applied to the analysis of samples with satisfactory results.