应用荧光光谱法研究了苯丙胺与牛血清白蛋白(BSA)相互反应的机理。结果表明:由于两者的相互反应,导致BSA的荧光有显著猝灭,且证明这一猝灭过程为静态猝灭,其结合点数(n)约为2。根据分子间的相互作用力与相关热力学参数间的相互关系,结合苯丙胺和BSA相互作用的焓变(ΔH)和熵变(ΔS)均大于0,可推断两者的相互作用力主要是疏水作用力。从同步荧光光谱可知:由于两者之间的反应,BSA的荧光强度显著降低,其分子中的酪氨酸和色氨酸的特征峰均产生紫移现象,氨基酸残基的亲水性减弱,疏水性增强,并推测苯丙胺与BSA的结合点位于色氨酸残基上。

Mechanism of interaction between amphetamine (APTM) and bovine serum albumin (BSA) was studied by fluorospectroscopy. It was shown that fluorescence quenching of BSA was observed due to its reaction with APTM, and the fluorescence quenching process was attributed to static quenching. Number of binding sites (n) was found to be 2. On the basis of the force of interaction between the molecules and correlation among the thermodynamic parameters, as well as the fact that values of ΔH and ΔS of the interaction between APTM and BSA were all >0, it was deduced that the force of the reaction was mainly due to hydrophobic action. It was found by synchronous fluorospectroscopic study, that as a result of interaction between the 2 compounds, significant decrease of fluorescence intensity of BSA, and hypsochromic shift of characteristic peaks of tyrosin and tryptophan in BSA molecules were observed, leading to enhancement of hydrophobicity and decrease of hydrophilicity of the remaining radicals of amino acids, and it was also inferred that binding sites of APTM with BSA were located at the remaining radical of tryptophan.