模拟酶催化荧光法测定没食子酸丙酯

Determination of Trace Propyl Gallate by Catalytic Fluorescence with Mimetic Enzyme

以pH值=10.1 NH_(4)Cl-NH_(3)·H_(2)O为缓冲溶液,牛血红蛋白催化L-酪氨酸和H_(2)O_(2)反应产生荧光,而没食子酸丙酯对体系的荧光有猝灭作用,据此建立一种测定微量没食子酸丙酯的新方法。在优化的实验条件下,没食子酸丙酯含量在0.00417~0.117 mg/L范围内与体系406 nm处的荧光强度降低值呈良好的线性关系,其线性回归方程为ΔF=10781ρ+270.67(ρ的单位为mg/L),相关系数(R)为0.9949,检出限为5.4×10^(-4)mg/L。该方法用于测定食用油中没食子酸丙酯的含量,测定结果的RSD为2.5%~3.1%,回收率为99.3%~105.2%。

Bovine hemoglobin can catalyze the reaction of L-tyrosine-H_(2)O_(2)to produce a fluorescence in pH value=10.1 NH_(3)·H_(2)O-NH_(4)Cl buffer solution and the system's fluorescence is quenched by propyl gallate,a new method for detecting propyl gallate was developed.Under the optimal conditions,the decreased fluorescence intensity at 406 nm is in proportion to the concentration of propyl gallate in the range of 0.00417~0.117 mg/L,with the linear regression equation ofΔF=10781ρ+270.67(the unit of ρis mg/L),the correlation coefficient of 0.9949,and the detection limit of 5.4×10^(-4)mg/L.The method was applied to determine the propyl gallate in edible oil,with the RSD of 2.5%~3.1%,and the recovery of 99.3%~105.2%.