Combination of hollow fiber-based liquid-phase microextraction with sweeping techniques in micellar electrokinetic chromatography for the determination of Strychnos alkaloids in human urine

Abstract

A new method for the enrichment of Strychnos alkaloids in biological samples via liquid-phase microextraction (LPME) based on porous polypropylene hollow fibers in combination with on-line sweeping in micellar electrokinetic chromatography was developed. The calibration curve was linear over the range of 20–200 ng mL −1 for both strychnine and brucine in human urine sample. The detection limits (S/N = 3:1) for strychnine and brucine were 1 ng mL −1 and 2 ng mL −1, respectively. The LPME-sweeping method has been successfully applied to the analysis of strychnine and brucine in real urine samples.