液-液-液三相液相微萃取-高效液相色谱法检测尿样中的安非他明和氯胺酮

建立了液-液-液三相液相微萃取与高效液相色谱联用技术测定尿样中的安非他明和氯胺酮的方法。考察了萃取溶剂、料液相pH值、搅拌速度、萃取时间和接受相HCl浓度等因素对富集因子的影响，得到了萃取溶剂为300 μL甲苯,料液相pH值为11,接受相为1.0 μL 0.1 mol/L HCl,搅拌速度为600 r/min,萃取时间为50 min的最佳实验条件。在该条件下,获得了较高的富集因子；方法的线性范围为安非他明0.01～10 μg/mL,氯胺酮0.01～5 μg/mL,相对标准偏差均小于2%,检测限均为5 ng/mL (S/N=3)。建立的三相液相微萃取方法能有效地去除复杂基体的干扰,有机溶剂消耗少,萃取效率高,是一种有效、灵敏的样品前处理方法,适合于尿样中安非他明和氯胺酮的测定。

Determination of Amphetamine and Ketamine in Human Urines Using High Performance Liquid Chromatography Coupled with Liquid-Liquid-Liquid Phase Microextraction

Liquid-liquid-liquid phase microextraction (LLLME) coupled with high performance liquid chromatography was developed for the determination of amphetamine and ketamine in human urines. The effects of the extraction solvent, the pH value of the donor solution, the stirring rate, the extraction time and HCl concentration in the acceptor phase on the enrichment factors of analytes were investigated. The optimal experimental conditions, 300 microL of toluene as the organic phase, pH 11 of the donor phase, 1.0 microL of 0.1 mol/L HCl as the acceptor phase, 600 r/min of the stirring rate, and 50 min of the extraction time, were obtained. Under the above conditions, high enrichment factors were reached. The linear ranges were from 0.01 to 10 microg/mL for amphetamine, and 0.01 to 5 microg/mL for ketamine. The relative standard deviations were lower than 2%. The limits of detection were 5 ng/mL for the two target compounds at signal-to-noise ratio of 3. The method with little solvent consumption may provide high analyte pre-concentration and excellent sample clean-up, and it is a sensitive and suitable method for the simultaneous determination of above two analytes in human urines.