title: Quantification of phosphatidylethanol 16:0/18:1, 18:1/18:1, and 16:0/16:0 in venous blood and venous and capillary dried blood spots from patients in alcohol withdrawal and control volunteers.
abstract: Phosphatidylethanol species (PEths) are promising biomarkers of alcohol consumption. Here, we report on the set-up, validation, and application of a novel UHPLC-ESI-MS/MS method for the quantification of PEth 16:0/18:1, PEth 18:1/18:1, and PEth 16:0/16:0 in whole blood (30 μL) and in venous (V, 30 μL) or capillary (C, 3 punches (3 mm)) dried blood spots (DBS). The methods were linear from 10 (LLOQ) to 2000 ng/mL for PEth 16:0/18:1, from 10 (LLOQ) to 1940 ng/mL for PEth 18:1/18:1, and from 19 (LLOQ) to 3872 ng/mL for PEth 16:0/16:0. Extraction efficiencies were higher than 55% (RSD < 18%) and matrix effects compensated for by IS were between 77 and 125% (RSD < 10%). Accuracy, repeatability, and intermediate precision fulfilled acceptance criteria (bias and RSD below 13%). Validity of the procedure for determination of PEth 16:0/18:1 in blood was demonstrated by the successful participation in a proficiency test. The quantification of PEths in C-DBS was not significantly influenced by the hematocrit, punch localization, or spot volume. The stability of PEths in V-DBS stored at room temperature was demonstrated up to 6 months. The method was applied to authentic samples (whole blood, V-DBS, and C-DBS) from 50 inpatients in alcohol withdrawal and 50 control volunteers. Applying a cut-off value to detect inpatients at 221 ng/mL for PEth 16:0/18:1 provided no false positive results and a good sensitivity (86%). Comparison of quantitative results (Bland-Altman plot, Passing-Bablok regression, and Wilcoxon signed rank test) revealed that V-DBS and C-DBS were valid alternatives to venous blood for the detection of alcohol consumption.
authors.affiliation: Federal Public Service Justice, National Institute of Criminalistics and Criminology, Chaussée de Vilvorde 100, 1120, Brussels, Belgium.
authors.forename: Natalie
authors.initials: N
authors.lastname: Kummer
authors.affiliation: Federal Public Service Justice, National Institute of Criminalistics and Criminology, Chaussée de Vilvorde 100, 1120, Brussels, Belgium.
authors.forename: Ann-Sofie
authors.initials: AS
authors.lastname: Ingels
authors.affiliation: Federal Public Service Justice, National Institute of Criminalistics and Criminology, Chaussée de Vilvorde 100, 1120, Brussels, Belgium.
authors.forename: Sarah M R
authors.initials: SM
authors.lastname: Wille
authors.affiliation: Laboratory of Psychological Medicine and Addictology, ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), Route de Lennik 800, 1070, Brussels, Belgium.
authors.forename: Catherine
authors.initials: C
authors.lastname: Hanak
authors.affiliation: Laboratory of Psychological Medicine and Addictology, ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), Route de Lennik 800, 1070, Brussels, Belgium.
authors.forename: Paul
authors.initials: P
authors.lastname: Verbanck
authors.affiliation: Laboratory of Toxicology, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000, Ghent, Belgium.
authors.forename: Willy E E
authors.initials: WE
authors.lastname: Lambert
authors.affiliation: Federal Public Service Justice, National Institute of Criminalistics and Criminology, Chaussée de Vilvorde 100, 1120, Brussels, Belgium.
authors.forename: Nele
authors.initials: N
authors.lastname: Samyn
authors.affiliation: Laboratory of Toxicology, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000, Ghent, Belgium. christophe.stove@ugent.be.
authors.forename: Christophe P
authors.initials: CP
authors.lastname: Stove
mesh_terms: D000328:Adult; D000368:Aged; D000428:Alcohol Drinking / Q000097:blood*; D015415:Biomarkers / Q000097:blood / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D059788:Dried Blood Spot Testing / Q000379:methods*; D005260:Female; D020404:Glycerophospholipids / Q000097:blood / Q000737:chemistry*; D006801:Humans; D008297:Male; D008875:Middle Aged; D013375:Substance Withdrawal Syndrome / Q000097:blood*; D053719:Tandem Mass Spectrometry / Q000379:methods*; D014838:Volunteers
chemical_list: D015415:Biomarkers; D020404:Glycerophospholipids; C051521:phosphatidylethanol
keywords: Biological samples; Drug monitoring/drug screening; Forensics/toxicology; Sampling