四环素猝灭聚酰胺-胺荧光机理及用于测定四环素含量

Fluorescence Quenching of Polyamidoamine Induced by Tetracycline and Determination of Tetracycline

在pH 1. 0的溶液中,四环素对聚酰胺-胺(PAMAM)的荧光有显著的猝灭作用,结合紫外-可见光谱研究发现,动态猝灭、静态猝灭和能量转移猝灭共同导致了PAMAM的荧光猝灭现象。且四环素浓度在0. 000 25~0. 125 mg/mL范围内与lg(F0/F)(F0是加入四环素前PAMAM的荧光强度,F是加入猝灭剂四环素后PAMAM的荧光强度)存在线性关系,回归方程为lg(F0/F)=11. 808c+0. 002 9 (c为四环素浓度,mg/mL),相关系数为0. 999 4,据此建立了一种通过猝灭PAMAM的荧光来定量测定四环素的方法。方法已被成功用于尿样中四环素的测定,加标回收率在96%~102%之间,方法检出限为12. 5 ng/mL。荧光猝灭法测定尿样中四环素的灵敏度高、检出限低、回收率高,能满足尿样中痕量四环素的测定要求。

In the solution of pH 1.0,tetracycline had a significantly quenching effect on the fluorescence of polyamidoamine(PAMAM).A nonlinear Stern-Volmer(S-V)plot and UV-visible spectra suggested that dynamic quenching,static quenching,and energy transfer quenching were responsible for the fluorescence quenching of PAMAM.And the concentration of tetracycline had a linear relationship with lg(F0/F)(F0 is the fluorescence intensity of PAMAM without tetracycline,F is the fluorescence intensity of PAMAM with tetracycline)in the range of 0.000 25~0.125 mg/mL.Its regression equation is lg(F0/F)=11.808c+0.002 9(c is the concentration of tetracycline,mg/mL)with acorrelation coefficient of 0.999 4.A method for determining of tetracycline was established based on the fluorescence quenching effect and had been successfully used for the determination of tetracycline in urine samples.The standard recovery rate of the method is in the range of 96%~102%and the detection limit is 12.5 ng/mL.The determination of tetracycline content in urine samples by a fluorescence quenching has high sensitivity,low detection limit and high recovery rate and the method can meet the determination demands of trace tetracycline in urine samples.