False identification of urinary ephedrine as methamphetamine by gas chromatography/mass spectrometry with a DB-17 column.
A 17-year-old motorcyclist was killed in a traffic accident. The urine sample collected at autopsy was screened by the Toxi-Lab system; it showed a possible presence of either methamphetamine (MA) or ephedrine (Eph). Gas chromatography-mass spectrometry (GC-MS) was carried out for a trifluoroacetyl (TFA)-derivatized sample after extraction with an Extrelut column. A peak was detected at the same retention time as that of the authentic Eph by GC-MS with a DB-17 wide-bore column; the mass spectrum of the peak was, however, very similar to that of MA. The presence of Eph and absence of MA were proved by GC-MS using a DB-1 column. The Eph in the urine was further confirmed by high performance liquid chromatography (HPLC)-MS using an ODS column. By the REMEDi HS system, Eph and methylephedrine were determined in the urine, and their concentrations (hydrochloride salt) were 0.752 and 2.13 micrograms/ml, respectively. Ethanol was detected as well in the blood (1.55 mg/ml) and urine (2.01 mg/ml) by a pulse heating method. Nicotine, caffeine and dihydrocodeine were also qualitatively detected in the urine by Toxi-Lab, HPLC-MS and REMEDi HS systems. The present case warned that urinary Eph can be misidentified as MA by GC-MS with an intermediately polar column after TFA derivatization.
Takayasu
T
T
Department of Legal Medicine, Kanazawa University Faculty of Medicine, School of Medicine, Japan.
Ohshima
T
T
Ohtsuji
M
M
Takayama
N
N
Kondo
T
T
Lin
Z
Z
Sato
Y
Y
Minamino
T
T
D000063:Accidents, Traffic; D000293:Adolescent; D002851:Chromatography, High Pressure Liquid; D004809:Ephedrine / Q000652:urine*; D005189:False Positive Reactions; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D008694:Methamphetamine / Q000652:urine*
D008694:Methamphetamine; D004809:Ephedrine