光谱法研究吡嗪酰胺与人血清白蛋白的作用机制

Study on interaction mechanism between pyrazinamide and human serum albumin by spectroscopic methods

用荧光光谱法研究了抗结核药物吡嗪酰胺(PZA)与人血清白蛋白(HSA)在不同温度下的相互作用.初步确定PZA对HSA的荧光猝灭机理主要为静态猝灭,并测定了二者之间形成基态化合物的结合常数K和作用位点数n.根据不同温度条件下的热力学函数,确定了PZA与HSA之间的主要作用力是氢键和范德华力.根据Forster非辐射能量转移原理,确定了PZA与HSA的结合距离。

The binding of pyrazinamide （PZA）, generally used as an antitubercular drug, to human serum albumin（HSA） has been investigated by spectroscopy at different temperatures. The quenching mechanism of fluorescence of HSA by PZA was found to be in static quenching procedure. The apparent binding constant Kand binding sites number n were measured by fluorescence quenching method. The thermodynamic parameters obtained from measured data at different temperatures showed that the binding of PZA to HSA involves hydrogen bond and van der Waals interaction. The binding distance between PZA and HSA was determined according to the theory of energy transfer. The effect of PZA on the conformation of HSA was also analyzed by synchronous fluorescence spectrometry and UV absorption spectrometry.