利用荧光光度法测定食品中蛋白质的含量;实验以六偏磷酸钠为稳定剂,巯基乙酸为修饰剂水相合成了具有优异光学性质的CdS量子点.基于CdS与牛血清白蛋白(BsA)反应后,荧光强度显著增强,建立了CdS荧光光度法测定蛋白质的新方法;体系的荧光强度与BSA浓度在0.001 43～0.250 mg·mL-1范围内呈良好的线性关系,线性方程为F=5444.301 03+43.32739c,相关系数r=0.9966,检出限为0.0014mg·mL-1;该法用于牛奶、蛋清中蛋白质含量的测定,并与标准方法(双缩脲法)做对照,结果满意.%Determination of protein content by fluorometry was carried out. In this experiment, CdS quantum dots(QDs)that have special spectral properties were prepared with sodium hexametaphosphate as stabilizer and mercapto acetic acid as modifier by hydrothermal synthesis method. Based on the increase in fluorescence intensity after CdS reacted with bovine serum albumin (BSA), a new method for the determination of protein was established. Results show that the fluorescence intensity of system has a good linear relationship with the concentration of BSA in the range of 0. 001 43～0. 250 mg · mL-1, and the linear equation was F=5 444. 301 03+43. 327 39c, relation coefficient (r) was 0. 996 6, the limit of detection was 0. 001 4 mg · mL-1. The method has been used for the determination of protein in milk and egg, and compared with the standard method (biuret method),and the results were satisfactory.
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