Determination of sedative-hypnotics in human hair by micropulverized extraction and liquid chromatography/quadrupole-Orbitrap mass spectrometry

作者：Miyaguchi Hajime^*

来源：Analytical Methods, 2014, 6(15): 5777-5783.

DOI：10.1039/c4ay00505h

A method was developed for quantification of 13 major sedative-hypnotics in human hair by liquid chromatography/high-resolution accurate mass spectrometry. A hair sample (5 mg) was micropulverized with 3.0 mol L-1 aqueous ammonium phosphate (pH 8.4). Liquid-liquid extraction was carried out twice with acetonitrile; the organic layer was concentrated and then reconstituted with 50 mu L of 0.1% formic acid in 10% acetonitrile, and then filtered. The filtrate (10 mu L) was analyzed with a Q Exactive (TM) hybrid mass spectrometer coupled with a liquid chromatograph. Using multiplexed selected ion monitoring mode, the quadrupole mass filter of the Q Exactive (TM) successfully eliminated large interferences, which enabled detection of the small peaks of the analytes. The tower limits of quantification (LLOQ) were 1.0 pg mg(-1) for brotizolam, diazepam, N-desmethyldiazepam, estazolam, flunitrazepam, nitrazepam, triazolam, ramelteon and zolpidem, and 4.0 pg mg(-1) for alprazolam, N-desmethylfludiazepam, etizolam and zopiclone. The accuracy and precision of the repeated analyses for all the analytes met FDA guidelines at three concentrations (LLOQ, 100 pg mg(-1) and 2.0 ng mg(-1)). The developed method was applied to hair samples from four patients with sleep disorders. Daily uses of brotizolam (8.8 pg mg(-1)), ethyl loflazepate (443 pg mg(-1) as desmethylfludiazepam), flunitrazepam (46.0 pg mg(-1)) and zolpidem (10.2 ng mg(-1)) were detected for Donor A. Occasional uses of etizolam (below the LLOQ) and zolpidem (60.0 pg mg(-1)) were detected for Donor B. The occasional use of etizolam (4.9 pg mg(-1)) was detected for Donor C. The concentration of zopiclone in the gray hair of Donor D was >10 ng mg(-1) in black hair and 187 pg mg(-1) in white hair.

• 出版日期2014-8-7