人血清蛋白-丙酮(乙醇)体系的荧光光谱及共振散射光谱特性

采用双池法研究了pH＝7．4Tris-HCl-丙酮(或乙醇)-HSA体系的荧光光谱及共振散射光谱。实验表明，丙酮对HSA在325nm处的荧光产生猝灭效应，其根本原因是丙酮的分子吸收。乙醇使HSA在325nm处的荧光增强，系由于乙醇破坏了HSA的高级结构，Trp残基暴露于HSA的表面并形成氢键所致。在pH=4．8NaAC-HAC缓冲溶液中，丙酮体积分数大于30％或乙醇体积分数大于40％时，HSA分子因高级结构被破坏而互相聚集，导致470nm处的共振散射急剧增强。

Fluorescence and Resonance Scattering Spectral Behavior of HSA-Acetone(Ethanol) Systems

The fluorescence and resonance scattering spectra of Tris-HCl-acetone (or ethanol)-HSA(human serum albumin) system(pH=7.4) were studied by a double-cell method. The results demonstrate the fluorescence quenching effect of acetone on the HSA system at 325 nm primarily due to the molecular absorption of acetone. The fluorescence intensity of HSA system at 325 nm was observerved enhanced by addition of ethanol. It could be explained in term of the destruction of high structures of HSA by ethanol and the formation of H-bondings from Trp exposed on the HSA surface. The destructed HSA species could be congregated in NaAC-HAC buffer solution of pH=4.8, when the concentration of acetone is >30% or that of ethanol is >40%. The congregation of HSA hurriedly enhances the resonance scattering intensity of the system at 470 nm.