Pipette tip solid-phase extraction and gas chromatography - mass spectrometry for the determination of methamphetamine and amphetamine in human whole blood.
Methamphetamine and amphetamine were extracted from human whole blood samples using pipette tip solid-phase extraction (SPE) with MonoTip C(18) tips, on which C(18)-bonded monolithic silica gel was fixed. Human whole blood (0.1 mL) containing methamphetamine and amphetamine, with N-methylbenzylamine as an internal standard, was mixed with 0.4 mL of distilled water and 50 microL of 5 M sodium hydroxide solution. After centrifugation, the supernatant was extracted to the C(18) phase of the tip (pipette tip volume, 200 microL) by 25 repeated aspirating/dispensing cycles using a manual micropipettor. Analytes retained in the C(18) phase were eluted with methanol by five repeated aspirating/dispensing cycles. After derivatization with trifluoroacetic anhydride, analytes were measured by gas chromatography - mass spectrometry with selected ion monitoring in the positive-ion electron impact mode. Recoveries of methamphetamine and amphetamine spiked into whole blood were more than 87.6 and 81.7%, respectively. Regression equations for methamphetamine and amphetamine showed excellent linearity in the range of 0.5-100 ng/0.1 mL. The limits of detection for methamphetamine and amphetamine were 0.15 and 0.11 ng/0.1 mL, respectively. Intra- and interday coefficients of variation for both stimulants were not greater than 9.6 and 13.8%, respectively. The determination of methamphetamine and amphetamine in autopsy whole blood samples is presented, and was shown to validate the present methodology.
Hasegawa
Chika
C
Department of Legal Medicine, Showa University School of Medicine, 1-5-8 Hatanodai, Tokyo 142-8555, Japan.
Kumazawa
Takeshi
T
Lee
Xiao-Pen
XP
Marumo
Akemi
A
Shinmen
Natsuko
N
Seno
Hiroshi
H
Sato
Keizo
K
D000661:Amphetamine / Q000097:blood*; D053593:Forensic Toxicology; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D008694:Methamphetamine / Q000097:blood*
D008694:Methamphetamine; D000661:Amphetamine