在pH 6.0的磷酸二氢钾-磷酸氢二钠缓冲溶液中,一定浓度的溴化十六烷基三甲基铵(CTMAB)与曙红(EY)反应,使其荧光强度剧增,当在EY-CTMAB中加入有机磷农药后,溶液在激发波长316 nm,发射波长550 nm处体系的荧光强度明显降低,且降低程度与有机磷农药的加入量呈线性关系.在优化的试验条件下,线性范围为0.024~0.56 mg·L-1,检出限(3S/N)为0.03 mg·L-1.该方法已用于小米和土壤中有机磷农药残留总量的检测,回收率在90.4%~100.4%之间,相对标准偏差(n=11)在2.61%~4.14%.

In a phosphate buffer of pH 6.0,the fluorescence intensity of eosin Y (EY) was significantly enhanced by the presence of definite amount of CTMAB when measured at the wavelengths of 316 nm (λex) and 550 nm (λem).Upon addition of an appropriate amount of organophosphorus pesticides (OPP′s),the fluorescence intensity of the EY-CTMAB system was decreased.Linear relationship between the magnitude of decrease in fluorescence intensity and mass concentration of OPP′s in the range of 0.024 to 0.56 mg·L-1,with detection limit (3S/N) of 0.03 mg·L-1.In the test for recovery by standard addition method using samples of rice and soil as matrixes,values of recovery in the range from 90.4% to 100.4% were found,with values of RSD′s (n=5) in the range of 2.61%-4.14%.