【摘要】 采用时间分辨荧光法,以铕离子为荧光探针,依据Eu3+-La3+-LMX-SDS稀土共发光体系,建立了测定洛美沙星(LMX)含量的新方法。研究了配合物的紫外及荧光光谱,分析了配合物的发光机理,考察了溶液pH值、缓冲溶液种类及反应试剂加入量对配合物荧光强度的影响。在优化的实验条件下,配合物荧光强度和洛美沙星浓度呈线性关系,相关系数为0.999 0,线性范围为5.0×10-7~1.0×10-5mol/L。方法的检出限为6.8×10-8mol/L,对5.0×10-6mol/L的洛美沙星溶液测定11次,RSD为0.6%。将该方法用于尿液中洛美沙星含量的测定,回收率为94%~104%。更多还原

【Abstract】 A time-resolved fluorometric method for the determination of lomefloxacin(LMX) based on columinescence effect of Eu3+-La3+-LMX-SDS(sodium dodecyl sulfate) system was developed using europium ion as fluorescent probe.UV and fluorescence spectra of the complexes were studied and the luminescence mechanism was discussed.In the complex of Eu3+-LMX-SDS,LMX absorbs UV light at 283 nm and transfers the energy to Eu3+,that is,intramolecular energy transfer occurring.In pH 6.8 hexamethylene tetramine(HMTA)-HCl buffer,Eu3+-LMX-SDS complex gives characteristic emission of Eu3+ at 616 nm,and the emission intensity can be enhanced greatly in the presence of La3+.The experimental conditions,including pH value and type of buffer,concentration of reaction reagents were investigated.The best conditions were obtained by using 3.0×10-6 mol/L Eu3+,2.5×10-4 mol/L SDS and 1.0×10-5 mol/L La3+ in pH 6.8 buffer.Under the optimum conditions,a good linearity was obtained between the fluorescence intensity and LMX concentration in the range of 5.0×10-7-1.0×10-5 mol/L.The linear regression equation was ΔI=-37.08+7.435c(×10-7 mol/L) with a correlation coefficient of 0.999 0.The detection limit was 6.8×10-8 mol/L and RSD for 5.0×10-6 mol/L LMX solution(n=11) was 0.6%.Effect of some coexisted ions on fluorescence intensity of the system was also investigated.The method was applied in the determination of LMX in urine samples with recoveries between 94% and 104%.更多还原