Chairat Jai-Ob-Orm. Confirmatory test of urine methamphetamine from dichloromethane layer of chemical reaction test kit by GC/MS . Master's Degree(Forensic Science). Mahidol University. : Mahidol University, 2004.
Confirmatory test of urine methamphetamine from dichloromethane layer of chemical reaction test kit by GC/MS
Abstract:
Methamphetamine is a category I narcotic which is easy to take and become
addicted. The importances of epidemic control are the detection in urine. Nowadays,
dichloromethane layer of chemical reaction test kit, which contains complex
compound of methamphetamine group and tetrabromophenolpthalein ethyl ester, is
directly used to confirm test by Thin Layer Chromatography (TLC). Gas
Chromatograph/Mass Spectrometer (GC/MS) is recommended because it is most
sensitive, specific and reliable. So the purpose of this study is to detect urine
methamphetamine in dichloromethane layer of chemical reaction test kit by GC/MS.
Urine methamphetamine having concentration of 1, 2, 3, 4 and 5
microgram/milliliters were provided to 10 samples per one level concentration.
Methamphetamine recovery was determined by extraction with TBPE,
TBPE+methanol/hydrochloric acid and liquid-liquid method. Percentage recovery
from three methods are not significantly different (P > 0.05). TBPE method, which
gives percentage recovery of 59.63 %, was selected to further use. It is most
convenient and rapid. 200 evidenced human urine samples from Department of
Forensic Medicine, Faculty of Medicine Siriraj Hospital and Scientific Crime
Detection Division were given 100 positive color tests and 100 negative color tests.
They were extracted by TBPE method and confirmed test by GC/MS. True positive
result has 30 cases (30.00%). True negative result has 100 cases (100.00%).
Therefore, the chemical reaction test kit has advantage to screening test. It should be
used to eliminate negative samples. Dichloromethane layer of positive color tests can
be directly used to confirm test by GC/MS.