采用分光光度法测定Trp—NO2^-体系的吸收光谱行为,加入表面活性剂Triton X-114胶束后,溶液的吸光度增大,体系得到增敏,由此建立一种快速简便测定L-色氨酸含量的方法.结果表明:色氨酸量在0.2~34.0mg·L^-1范围与其吸光度呈线性关系,其直线回归方程为A=0.777ρ-0.0119,相关系数r=0.994,检出限为0.054mg·L^-1,该方法具有灵敏度高、操作简捷的优点.在优化参数条件下对粮食等多种样品中的L-色氨酸进行分析,结果令人满意.
The absorption spectral behavior of the system Trp-NO2 is studied in Triton X-114 medium. Absorbance of the system increases with the addition of the surfactant micelle Triton X-114, thereby enhances the sensitivity of the system. Based on this, a novel surfactant-sensitized spectrophotometry method for the determination of L-tryptophan has been developed. The results show that under the optimal conditions, the linear range of calibration curve for the determination of L- tryptophan is 0.2-34.0 mg·L^-1 , and the detection limit is 0. 054 mg·L^-1. It has been applied to the determination of L-tryptophan in food samples with satisfactory results.