中空纤维液-液-液微萃取/HPLC分析人尿液中麻黄碱及伪麻黄碱

建立了中空纤维液-液-液微萃取高效液相色谱对人尿液中的麻黄碱和伪麻黄碱进行纯化、分离、富集以及测定的方法。采用中空纤维三相微萃取装置,考察了影响萃取的因素,确定了萃取条件:中空纤维壁上的有机相为正辛醇,以50μL盐酸溶液(pH 2.0)为接受相,在室温下萃取60 min。该条件下麻黄碱和伪麻黄碱的富集倍数分别为180倍和220倍,两者的线性范围分别为0.01～5 mg/L和0.005～0.75 mg/L,相关系数(r)分别为0.998 2、0.997 8,定量下限分别为0.01、0.005 mg/L。该方法使用极少量的有机溶剂,便可有效地对尿样中麻黄碱和伪麻黄碱进行纯化、分离和富集,萃取效率高,可用于尿液中麻黄碱和伪麻黄碱的同时测定。

Determination of Trace Ephedrine and Pseudoephedrine in Urine Sample by Hollow Fiber-Liquid Phase Microextraction and HPLC

A simple and sensitive method based on hollow fiber liquid phase microextraction(HF-LPME) was developed to separate,purify and enrich ephedrine and pseudoephedrine in human urine sample.With HF-LPME device,the extraction conditions were optimized.Under the optimal conditions using n-octyl alcohol as organic phase impregnated in the pores of hollow fiber,and acidic microliter solution(pH 2.0)as acceptor phase,the enrichment factors of 180 for ephedrine and 220 for pseudoephedrine were obtained at room temperature with extraction time of 60 min.The calibration curves were linear in the ranges of 0.01-5 mg/L and 0.005-0.75 mg/L for ephedrine and pseudoephedrine,with their correlation coefficients of 0.998 2 and 0.997 8,respectively.The limits of quantitation(S/N=10) were 0.01 mg/L and 0.005 mg/L,respectively.With the advantages of low organic solvent consumption and high extraction efficiency,the method was suitable for the simultaneous determination of ephedrine and pseudoephedrine in urine sample.