title: Rapid, simple, and highly sensitive analysis of drugs in biological samples using thin-layer chromatography coupled with matrix-assisted laser desorption/ionization mass spectrometry.
abstract: Rapid and precise identification of toxic substances is necessary for urgent diagnosis and treatment of poisoning cases and for establishing the cause of death in postmortem examinations. However, identification of compounds in biological samples using gas chromatography and liquid chromatography coupled with mass spectrometry entails time-consuming and labor-intensive sample preparations. In this study, we examined a simple preparation and highly sensitive analysis of drugs in biological samples such as urine, plasma, and organs using thin-layer chromatography coupled with matrix-assisted laser desorption/ionization mass spectrometry (TLC/MALDI/MS). When the urine containing 3,4-methylenedioxymethamphetamine (MDMA) without sample dilution was spotted on a thin-layer chromatography (TLC) plate and was analyzed by TLC/MALDI/MS, the detection limit of the MDMA spot was 0.05 ng/spot. The value was the same as that in aqueous solution spotted on a stainless steel plate. All the 11 psychotropic compounds tested (MDMA, 4-hydroxy-3-methoxymethamphetamine, 3,4-methylenedioxyamphetamine, methamphetamine, p-hydroxymethamphetamine, amphetamine, ketamine, caffeine, chlorpromazine, triazolam, and morphine) on a TLC plate were detected at levels of 0.05-5 ng, and the type (layer thickness and fluorescence) of TLC plate did not affect detection sensitivity. In addition, when rat liver homogenate obtained after MDMA administration (10 mg/kg) was spotted on a TLC plate, MDMA and its main metabolites were identified using TLC/MALDI/MS, and the spots on a TLC plate were visualized by MALDI/imaging MS. The total analytical time from spotting of intact biological samples to the output of analytical results was within 30 min. TLC/MALDI/MS enabled rapid, simple, and highly sensitive analysis of drugs from intact biological samples and crude extracts. Accordingly, this method could be applied to rapid drug screening and precise identification of toxic substances in poisoning cases and postmortem examinations.
authors.affiliation: National Research Institute of Police Science, 6-3-1, Kashiwanoha, Kashiwa, Chiba 277-0882, Japan. kuwayama@nrips.go.jp
authors.forename: Kenji
authors.initials: K
authors.lastname: Kuwayama
authors.forename: Kenji
authors.initials: K
authors.lastname: Tsujikawa
authors.forename: Hajime
authors.initials: H
authors.lastname: Miyaguchi
authors.forename: Tatsuyuki
authors.initials: T
authors.lastname: Kanamori
authors.forename: Yuko T
authors.initials: YT
authors.lastname: Iwata
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Inoue
mesh_terms: D000818:Animals; D002855:Chromatography, Thin Layer / Q000191:economics / Q000379:methods*; D006801:Humans; D008099:Liver / Q000378:metabolism; D018817:N-Methyl-3,4-methylenedioxyamphetamine / Q000097:blood* / Q000378:metabolism / Q000652:urine*; D011619:Psychotropic Drugs / Q000097:blood* / Q000378:metabolism / Q000652:urine*; D051381:Rats; D012680:Sensitivity and Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000191:economics / Q000379:methods*; D013997:Time Factors
chemical_list: D011619:Psychotropic Drugs; D018817:N-Methyl-3,4-methylenedioxyamphetamine