title: Direct determination of diazepam and its glucuronide metabolites in human whole blood by μElution solid-phase extraction and liquid chromatography-tandem mass spectrometry.
abstract: A μElution solid-phase extraction (SPE) liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for simultaneous determination of diazepam, nordiazepam, oxazepam, oxazepam glucuronide, temazepam and temazepam glucuronide in human whole blood is presented. 200 μL of whole blood samples were loaded onto a Waters Oasis HLB 96-well μElution SPE plate using 75 μL of methanol as the elution solvent, and the eluents were injected into an Eclipse XDB C18 column. No hydrolysis, solvent transfer, evaporation or reconstitution was involved in the sample preparation procedures. Tandem mass spectrometric detection with Turbo Ion Spray was conducted via multiple reaction monitoring (MRM) under positive ionization mode. The method was validated and proved to be accurate (accuracy within 93-108%), precise (intra-day RSD<9.9% and inter-day RSD<7.2%) and sensitive with limits of detection (LOD) in the range of 0.05-0.25 ng/mL for all the compounds. Extraction recoveries were in the range of 31-80% for all the analytes. This method demonstrated to be reproducible and reliable. The applicability of the method was demonstrated by analysis of several forensic cases involving diazepam and its metabolites.
authors: Shanghai Institute of Forensic Science, Shanghai Key Laboratory of Crime Scene Evidence, Shanghai 200083, China.
authors: Rong
authors: R
authors: Wang
authors: Xin
authors: X
authors: Wang
authors: Chen
authors: C
authors: Liang
authors: Chunfang
authors: C
authors: Ni
authors: Lingjuan
authors: L
authors: Xiong
authors: Yulan
authors: Y
authors: Rao
authors: Yurong
authors: Y
authors: Zhang
mesh_terms: D002853:Chromatography, Liquid; D003975:Diazepam / Q000097:blood*; D053593:Forensic Toxicology / Q000379:methods; D006801:Humans; D006993:Hypnotics and Sedatives / Q000097:blood*; D057230:Limit of Detection; D003708:Nordazepam / Q000097:blood; D010076:Oxazepam / Q000031:analogs & derivatives / Q000097:blood; D015203:Reproducibility of Results; D052616:Solid Phase Extraction / Q000379:methods*; D053719:Tandem Mass Spectrometry; D013693:Temazepam / Q000031:analogs & derivatives / Q000097:blood
chemical_list: D006993:Hypnotics and Sedatives; C026256:oxazepam glucuronide; C072757:temazepam glucuronide; D003708:Nordazepam; D010076:Oxazepam; D013693:Temazepam; D003975:Diazepam
keywords: 96-Well μElution plate solid-phase extraction; Diazepam; Diazepam glucuronides; Human whole blood; LC–MS/MS