基于氨基化碳量子点荧光增强测定氨苄青霉素

摘要

采用水热法制备碳量子点,通过碳量子点与氨水反应使其表面氨基化,氨苄青霉素与氨基化碳量子点作用后,使其荧光显著增强,由此建立测定药物中氨苄青霉素的荧光光度法.在比色管中依次加入0.016 mol·L-1氨基化碳量子点溶液1.00 mL和样品溶液0.45 mL,pH 7.0三酸缓冲溶液1 mL,用水定容至5 mL,室温下反应30 min后,在激发波长340 nm、发射波长433 nm处测量溶液相对荧光强度(F/F0,F、F0分别为加入与不加入氨基化碳量子点时体系的荧光强度).氨苄青霉素质量浓度在2.0×10-6～9.0×10-5mol· L-1内与体系的相对荧光强度呈线性关系,检出限(3S/N)为1.2×10-6mol·L-1.加标回收率为99.0％～109％,测定值的相对标准偏差(n=5)小于2.0％.%Carbon quantum dots were prepared by hydrothermal method and amination on the surface by reaction with aqueous ammonia.After interaction with ampicillin,the fluorescence intensity of amino-functional carbon quantum dots (N-CQDs) was enhanced significantly.Base on this fact,a method for determination of ampicillin by fluorophotometry was established.In a colorimetric test tube,1.00 mL of 0.016 mol · L-1 N-CQDs solution,0.45 mL of sample solution,1 mL of Britton Robinson buffer solution (pH 7.0) were added successively,and the solution was diluted up to 5 m L.After reaction for 30 min at room temperature,the relative fluorescence intensity (F/F0) was measured at excitation wavelength of 340 nm and emission wavelength of 433 nm.F,F0 were the fluorescence intensity of the solution with and without the addition of N-CODs.Linear relationship was found between relative fluorescence intensity and concentration of ampicillin in the range of 2.0 × 10-6-9.0 × 10-5 mol · L-1,with detection limit (3S/N) of 1.2 × 10-6 mol · L-1.Values of recovery obtained by standard addition method in the range of 99.0％-109％ and RSDs (n=5) were less than 2.0％.