摘要
采用248nm(FKr)激光对色氨酸的水溶液进行了较为详细的研究,得到一些新的实验结果,以前都认为色氨酸水溶液先解后,在330nm和530nm(580nm,pH<5)为色氨酸的两个吸收带,而我们的实验表明,330nm和530nm的吸收分别是C-中心和N-中心的色氨酸中性游离基,且是一对互变异构体。另外,在460nm处色氨酸三线态的吸收也被观测到,并且其衰减动力学为二级反应。而同时光解过程为单光子过程,这意味着三线态接产生P-型荧光的方式衰减激发出的电子至少有一部分直接或间接的来源于三线态。另外以脉冲辐解作为辅助手段,观测到了Trp/NH^(?)在350nm强烈的吸收,在这些实验事实的基础上提出了较为详细的色氨酸水溶液的光解过程。
The photolysis of Trp aqueous solution was studied in detail in our laboratory recently. The absorptions at 330nm and 530nm(580nm, pH<5) were ascribed to carbon-center and nitrogen-center radical respectively. The behaviors of these species at different pH were observed. The ejected electrons are captured largely by Trp itself, giving a new absorption at 350nm. The triplet state of Trp with 460nm absorption decays following second order kinetics and the photolysis process is carried on with single photon. It was suggested that the ejected electrons were related to the triplet state of Trp.
