title: Simultaneous determination of carisoprodol and meprobamate in human hair using solid-phase extraction and gas chromatography/mass spectrometry of the trimethylsilyl derivatives.
abstract: Carisoprodol (CSP) is a musculoskeletal relaxant whose active metabolite is meprobamate (MPB). This drug has recently been noticed to be abused as an inexpensive alternative to illicit drugs in Korea. A method using solid-phase extraction (SPE) and gas chromatography/mass spectrometry (GC/MS) was developed for the determination of CSP and MPB in human hair. Hair samples (30 mg) were washed with distilled water and acetone, cut into small fragments (<1 mm), incubated in 1.0 M HCl overnight at 50 degrees C, and then adjusted to pH 6.5. The drugs were extracted from the resulting hydrolyzed solutions using a SPE column. The eluents were evaporated to dryness, then derivatized using N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) with 1% trimethylchlorosilane (TMCS) at 120 degrees C for 30 min. The derivatized extract (1 microL) was injected into the GC/MS system. Recoveries were in the range of 91.5-93.1% for CSP and 85.5-93.0% for MPB. The linear ranges were 0.5-10.0 ng/mg for both CSP and MPB with good correlation coefficients (r(2) = 0.995). The intra-day precision and accuracy ranged from 1.5 to 9.3% and -17.5 to 3.6%, respectively, and the inter-day precision and accuracy ranged from 3.9 to 6.2% and -15.0 to -3.9%, respectively. The limits of detection for CSP and MPB were 0.13 and 0.12 ng/mg, respectively. The applicability of the method was proven by analyzing a hair sample from an authentic abuser.
authors.affiliation: Drug Analysis Laboratory, Forensic Science Division, Supreme Prosecutors' Office, Seoul, Korea.
authors.forename: Jin Young
authors.initials: JY
authors.lastname: Kim
authors.forename: Moon Kyo
authors.initials: MK
authors.lastname: In
authors.forename: Ki-Jung
authors.initials: KJ
authors.lastname: Paeng
authors.forename: Bong Chul
authors.initials: BC
authors.lastname: Chung
mesh_terms: D000328:Adult; D002328:Carisoprodol / Q000032:analysis* / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006197:Hair / Q000737:chemistry*; D006801:Humans; D008297:Male; D008620:Meprobamate / Q000032:analysis* / Q000737:chemistry; D009125:Muscle Relaxants, Central / Q000032:analysis* / Q000737:chemistry; D015813:Substance Abuse Detection / Q000379:methods*; D014297:Trimethylsilyl Compounds / Q000737:chemistry
chemical_list: D009125:Muscle Relaxants, Central; D014297:Trimethylsilyl Compounds; D002328:Carisoprodol; D008620:Meprobamate