Background: Liquid chromatography linked to tandem mass spectrometry (LC/MS/MS) provides the ability to identify a range of benzodiazepines in accordance with European Union criteria and is an attractive method for the confirmation of benzodiazepines following immunoassay screening.
Methods: An LC/MS/MS method to detect and quantitate the six most common benzodiazepines/metabolites (diazepam, nitrazepam, nordiazepam, oxazepam, temazepam and 7-aminonitrazepam) was developed together with a qualitative screening method for a further 11 benzodiazepines/metabolites. These methods were used for confirmation of 250 urine samples submitted for routine drug screening by immunoassay for benzodiazepines (100 samples positive for a benzodiazepine, assay cut-off >200 microsg/L).
Results: The lower limits of detection and quantitation were less than 2.5 and 5 microg/L for the six most common benzodiazepines. Recoveries ranged between 97% and 102% and calibration curves were linear to at least 4000 microg/L (r = 0.99). Intra and inter-assay imprecision were <10% (n = 10) and <20% (n = 15), respectively. Confirmation of benzodiazepines using LC/MS/MS was achieved for 89% of the immunoassay-positive urine samples. Of the immunoassay-negative urine samples, 31% of these demonstrated a benzodiazepine using LC/MS/MS.
Conclusion: The validated LC/MS/MS method developed is effective for the confirmation of immunoassay screening results for benzodiazepines. The lower limit of detection and assay specificity offers a longer window of detection and more detailed clinical information compared with immunoassay screening.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1258/acb.2009.009172 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Phosphorylation of Bok at Ser-8 blocks its ability to suppress IPR-mediated calcium mobilization.
Cell Commun Signal
January 2025
Department of Pharmacology, SUNY Upstate Medical University, Syracuse, NY, 13210, USA.
Background: Bok is a poorly characterized Bcl-2 protein family member with roles yet to be clearly defined. It is clear, however, that Bok binds strongly to inositol 1,4,5-trisphosphate (IP) receptors (IPRs), which govern the mobilization of Ca from the endoplasmic reticulum, a signaling pathway required for many cellular processes. Also known is that Bok has a highly conserved phosphorylation site for cAMP-dependent protein kinase at serine-8 (Ser-8).
View Article and Find Full Text PDFMetabolically activated and highly polyfunctional intratumoral VISTA regulatory B cells are associated with tumor recurrence in early-stage NSCLC.
Mol Cancer
January 2025
Department of Medical and Surgical Sciences for Children and Adults, University of Modena and Reggio Emilia, via Campi, 287, Modena, 41125, Italy.
B cells have emerged as central players in the tumor microenvironment (TME) of non-small cell lung cancer (NSCLC). However, although there is clear evidence for their involvement in cancer immunity, scanty data exist on the characterization of B cell phenotypes, bioenergetic profiles and possible interactions with T cells in the context of NSCLC. In this study, using polychromatic flow cytometry, mass cytometry, and spatial transcriptomics we explored the intricate landscape of B cell phenotypes, bioenergetics, and their interaction with T cells in NSCLC.
View Article and Find Full Text PDFQuantitative proteomic analysis unveils a critical role of VARS1 in hepatocellular carcinoma aggressiveness through the modulation of MAGI1 expression.
Mol Cancer
January 2025
Department of Cell Biology, Physiology, and Immunology, University of Córdoba, CIBER Pathophysiology of Obesity and Nutrition (CIBERobn), Córdoba, 14004, Spain.
Background: Hepatocellular carcinoma (HCC) genetic/transcriptomic signatures have been widely described. However, its proteomic characterization is incomplete. We performed non-targeted quantitative proteomics of HCC samples and explored its clinical, functional, and molecular consequences.
View Article and Find Full Text PDFPseudocitrobacter cyperus, a novel bacterial species recovered from Cyperus alternifolius in Egypt.
BMC Microbiol
January 2025
Microbiology and Immunology Department, October University for Modern Sciences and Arts (MSA), Giza, Egypt.
Background: Strain Cyp38S was isolated as an endophyte from the plant Cyperus alternifolius, collected along the banks of the River Nile in 2019. Preliminary analysis tentatively identified Cyp38S as belonging to the genus Pseudocitrobacter.
Methods: The preliminary identification of Cyp38S was performed using the VITEK2 identification system, MALDI-TOF-MS, and 16S rRNA gene sequencing.
Indication of the sensitivity of Pinaceae species growing in Eastern Central Europe to ground-level ozone pollution.
Environ Sci Pollut Res Int
January 2025
Slovak Hydrometeorological Institute, Jeséniova 17, Bratislava, 833 15, Slovakia.
This study focused on testing the response of the assimilation apparatus of evergreen Pinaceae species to increasing levels of oxidative stress simulated in manipulative experiments. Needles were collected from mature individuals of Pinus mugo, Pinus cembra, Pinus sylvestris, Abies alba, and Picea abies at the foothill (FH) and alpine treeline ecotone (ATE) in the High Tatras (Western Carpathians). The injury index (INX), quantified by the modified electrolyte leakage (EL) method, indicated severe needle damage due to exposure to extremely high levels of O.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!