氯酚类物质测定新方法及其与人血清白蛋白的相互作用

Determination of Chlorophenol and Its Interaction with Human Serum Albumin

建立了氯酚类物质(CPs)新的检测方法,通过光谱学特征,探讨了CPs与人血清白蛋白(HSA)的结合反应机制。以2,4-二氯苯酚(2,4-DCP)为代表,考察了溶液酸度、试剂用量、反应温度和反应时间等因素对CPs-HSA体系荧光猝灭强度的影响。由Stern-Volm er方程求出2,4-DCP与HSA的猝灭常数(Kq)及反应热力学参数。结果表明,方法线性范围为0.075~0.65 mg/L,检出限为0.226μg/L(以2,4-DCP计)。该方法与C18柱固相萃取技术相结合,用于水中CPs的测定,相对标准偏差小于2.9%,加标回收率为96%~106%。对荧光猝灭机理的探讨结果表明,2,4-DCP致HSA内源荧光猝灭以静态猝灭为主。

A new method for the determination of ehlorophenols（CPs） was developed. It was based on the quenching of the fluorescence intensity of human serum albumin（HSA） by ehlorophenols. 2,4-diehlorophenol（2,4-DCP） was selected as the representative of CPs. The reaction mechanism of 2,4- DCP with HSA was studied by fluoreseenee speetrophotometry. The affeets of solution aeidity, reagent dosage, temperat^are and reaction time on the quenehing of fluoreseenee intensity of 2,4-DCP - HSA system were studied. Using the Stern - Volmer equation, the quenching constant （Kq） and the basic thermodynamic parameters of the 2,4-DCP - HSA system were obtained. The linear range of the calibration curve of 2,4-DCP was 0. 075 -0.65 mg/L with a detection limit of 0. 226μg/L. Satisfactory results were obtained when the method was used together with the solid phase extraction（SPE） to determine 2,4-DCP in water sample. The relative standard deviation was less than 2. 9% and the recovery range was 96% - 106% . It was found that the fluorescence quenching mechanism of 2,4-DCP with HSA was mainly a statie quenching.