Solid-phase extraction in amphetamine and methamphetamine analysis of urine.
A systematic evaluation that compares the recoveries of methamphetamine and amphetamine from spiked urine using C8, C18, strong cation exchanger (SCX), and C8-SCX mixed procedures (solid-phase extraction) is reported. Optimized experimental conditions including pH of the sample, solvent composition, and urine concentration for different solid-phase extraction sorbents were studied. The largest recoveries--greater than 86% for methamphetamine and greater than 88% for amphetamine--were achieved with a mixed adsorbent (C8-SCX) and mixed elution solvent CH2Cl2-i-propanol-NH4OH (78:20:2) at pH 6. The concentration of the urine matrix did not affect the extraction efficiency. The detection limits of methamphetamine and amphetamine in urine were obtained at 0.03 and 0.07 micrograms/mL, respectively, using gas chromatographic-mass spectrometric analysis operated in the electron impact mode.
Lee
M R
MR
Department of Chemistry National Chung-Hsing University, Taichung, Taiwan (R.O.C.).
Yu
S C
SC
Lin
C L
CL
Yeh
Y C
YC
Chen
Y L
YL
Hu
S H
SH
D000327:Adsorption; D000661:Amphetamine / Q000652:urine*; D002411:Cation Exchange Resins; D000697:Central Nervous System Stimulants / Q000652:urine*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008694:Methamphetamine / Q000652:urine*
D002411:Cation Exchange Resins; D000697:Central Nervous System Stimulants; D008694:Methamphetamine; D000661:Amphetamine