title: Rapid and sensitive determination of strychnine and brucine in human urine by capillary electrophoresis with field-amplified sample stacking.
abstract: A simple, rapid, sensitive and low-cost method using capillary electrophoresis (CE) coupled with field-amplified sample stacking (FASS) has been developed and validated for the simultaneous determination of strychnine and brucine residues in human urine. Before sample loading, a water plug (3.5 kPa, 3 s) was injected to contain sample cations and to permit FASS. Electrokinetic injection at a voltage (20 kV, 25 s) was then used to introduce cations. Separation was performed using 20 mM acetate buffer (pH 3.8) with an applied voltage of 20 kV. The calibration curves were linear over a range of 8.00-2.56 infinity 10(2) ng/mL (r = 0.9995) for strychnine and 10.0-3.20 x 10(2) ng/mL (r = 0.9999) for brucine. Extraction recoveries in urine were greater than 79.6 and 82.8% for strychnine and brucine, respectively, with an RSD of less than 4.9%. The detection limits (signal-to-noise ratio 3) for strychnine and brucine were 2.00 and 2.50 ng/mL, respectively. A urine sample from one healthy female volunteer (26 years old, 50 kg) was pretreated and analyzed. Strychnine and brucine levels in urine could be detected 24 h after administration. On these grounds, this method was feasible for application to preliminary screening of trace levels of abused drugs for both doping control and forensic analysis.
authors.affiliation: Department of Pharmaceutical Analysis, School of Pharmacy, Hebei Medical University, 361 East Zhongshan Road, Shijiazhuang City, People's Republic of China.
authors.forename: Junmei
authors.initials: J
authors.lastname: Li
authors.forename: Ye
authors.initials: Y
authors.lastname: Jiang
mesh_terms: D000328:Adult; D002021:Buffers; D002138:Calibration; D053801:Capillary Electrochromatography / Q000379:methods*; D004563:Electrochemistry; D005260:Female; D005554:Forensic Medicine; D006801:Humans; D006863:Hydrogen-Ion Concentration; D011042:Poisons / Q000652:urine*; D012015:Reference Standards; D015203:Reproducibility of Results; D012996:Solutions; D013056:Spectrophotometry, Ultraviolet; D013331:Strychnine / Q000031:analogs & derivatives* / Q000652:urine*; D031461:Strychnos nux-vomica / Q000737:chemistry
chemical_list: D002021:Buffers; D011042:Poisons; D012996:Solutions; C083806:brucine; D013331:Strychnine