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

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. (c) 2007 Zhi Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.