Determination of Ethylglucuronide in Oral Fluid by Ultra-Performance Liquid Chromatography-Tandem Mass Spectrometry (original) (raw)

Development and validation of a GC-MS/MS method for the determination of ethylglucuronide in human urine and serum

Annales de Toxicologie Analytique, 2011

Objectives: Ethyl-β-D-6-glucuronide (EtG) is a minor phase-II metabolite of ethanol. The aim of this work was to develop and validate a gas chromatography negative chemical ionization tandem mass spectrometry (GC-NCI-MS/MS) method to measure EtG levels in human urine and serum with both high sensitivity and specificity. Methods: EtG was extracted and purified from 1 mL urine or 0.5 mL serum by solid-phase extraction (SPE) using Mixed-mode Anion-eXchange (Oasis® MAX) extraction cartridges, followed by derivatization with pentafluoropropionic anhydride (PFPA). The analysis was performed in the multiple reaction monitoring (MRM) mode using the transitions m/z 496→163 (for EtG quantification), m/z 347→163 and m/z 496→119 (for identification), and m/z 501→163 for the internal standard EtG-D5. The validation procedure was performed according to the guidelines of the French Society of Analytical Toxicology (SFTA) and the French Committee of Accreditation (COFRAC; LAB GTA 04). Results: Calibration curves were linear in the concentration range of 10 to 10 000 ng/mL and 5 to 1 000 ng/mL in urine and serum, respectively, with a coefficient of correlation (r) above 0.996. The LOD and LOQ values were 5 and 10 ng/mL, respectively, for both matrices. The intra-and inter-day precision (relative standard deviation RSD%) and relative bias were less than 20%. Conclusion: To our knowledge, this is the first report of the application of a GC-MS/MS method for EtG measurement in urine and serum. The LOQ achieved appears to be better than those reported in the literature using other validated analytical techniques. This method could be used routinely for EtG measurement in various clinical and forensic contexts.

Validated method for the determination of ethylglucuronide and ethylsulfate in human urine

Analytical and Bioanalytical Chemistry, 2011

Detection of the alcohol metabolites ethylglucuronide (EtG) and ethylsulfate (EtS) has become routine in many forensic laboratories over the last few years. Most previously published methods using liquid chromatography coupled with electrospray tandem mass spectrometry require a post-chromatographic addition of solvent and/or extensive sample preparation prior to analysis. The aim of the study was to develop a simplified method. To 20 μL urine, internal standard containing EtG-d5 and EtS-d 5 was added and the mixture was treated with elution buffer internal standard. EtG and EtS were separated using a Shimadzu Prominence high performance liquid chromatography (HPLC) system with a C18 separation column (Restek Ultra Aqueous C18, 4.6×150 mm, 5 μm), using isocratic elution with a mobile phase consisting of 10 mM ammonium acetate buffer pH 7 (total run time, 6 min). The compounds were detected using an Applied Biosystems API 5000 liquid chromatography tandem mass spectrometry system (atmospheric pressure chemical ionization, multiple-reaction monitoring mode). The method was fully validated according to international guidelines. The assay was found to be selective for the compounds of interest. It was linear from 0.1 to 10 mg/L for all analytes (R 2 >0.99). Matrix effects studies showed the presence of a slight but consistent ion enhancement (n=10 different urine samples) at low concentrations and no effects at higher concentrations. Accuracy data were between 0.75% and 8.1% bias for EtG and between −5.0% and −11.3% bias for EtS. Precision data were between 4.3% and 6.9% relative standard deviations (RSD) for EtG and between 6.0% and 7.5% RSD for EtS. No instability was observed after repeated freezing and thawing. This fast, reliable, and accurate method enables the detection and quantification of alcohol metabolites in urine. The method is easier to use and more sensitive than previously published methods.

Quantitation of ethyl glucuronide in serum & urine by gas chromatography - mass spectrometry

Background & objectives: Alcohol misuse has now become a serious public health problem and early intervention is important in minimizing the harm. Biochemical markers of recent and high levels of alcohol consumption can play an important role in providing feedback regarding the health consequences of alcohol misuse. Existing markers are not sensitive to recent consumption and in detecting early relapse. Ethyl glucuronide (EtG), a phase-II metabolite of ethanol is a promising marker of recent alcohol use and can be detected in body fluids. In this study an analytical technique for quantitation of EtG in body fluids using solid-phase extraction (SPE) and gas chromatography (GC) with mass spectrometric detection (MS) was developed and validated. Methods: De-proteinization of serum and urine samples was done with perchloric acid and hydrochloric acid, respectively. Serum samples were passed through phospholipids removal cartridges for further clean up. EtG was isolated using amino propyl solid phase extraction columns. Chromatographic separation was achieved by gas chromatography with mass spectrometry. Results: Limit of detection and limit of quantitation were 50 and 150 ng/ml for urine and 80 and 210 ng/ml for serum, respectively. Signal to noise ratio was 3:1, mean absolute recovery was 80-85 per cent. Significant correlation was obtained between breath alcohol and serum EtG levels (r=0.853) and urine EtG and time since last abuse (r = -0.903) in clinical samples. Interpretation & conclusions: In the absence of other standardized techniques to quantitate EtG in biological samples, this gc -ms method was found to have high throughput and was sensitive and specific.

Demonstration of ethyl glucuronide in dental tissue samples by liquid chromatography/electro-spray tandem mass spectrometry

Journal of Forensic and Legal Medicine

Ethyl glucuronide (EtG) has been studied in various tissues and body fluid for determination of alcohol intake. However, no study, dealing with EtG analysis in dental tissue, was performed so far. In this study, we aimed to demonstrate EtG levels in dental tissue. Michigan Alcohol Screening Test (MAST) was performed to 29 participants. Following the test, cases were divided into three groups as non-hazardous alcohol users, alcohol abusers and 6 controls who verbally declared that they were abstainers. A total of 29 tooth specimens, obtained from participants, was included in the study. These specimens were analyzed using LC/MS/MS. All of the participants included in the study were male. According to the MAST outcomes 14 of the participants were non-hazardous alcohol users, and 9 were alcohol abusers, while 6 patients verbally declared that they were abstainers. Dental tissue analyses revealed EtG levels ranging between EtG<LOD and 23.39pg/mg. EtG levels were observed to be <LO...

A simplified approach for determination of urinary ethyl glucuronide by gas chromatography–mass spectrometry

2021

Urinary ethyl glucuronide (EtG), an alcohol biomarker, plays an essential role in monitoring alcohol abstinence and relapse during treatment for alcohol dependence. Detection of this biomarker has become a routine in many clinical and forensic laboratories over the last few years. Most previously published methods commonly use hyphenated chromatographic techniques along with extensive extraction procedure before analysis. This work aimed to develop and validate an electron impact ionization mode gas chromatography–mass spectrometry method to measure ethyl glucuronide levels in human urine. For its determination, urine samples were dried under a gentle stream of nitrogen, derivatized with N,O-bis(trimethylsilyl) trifluoroacetamide, incubated, and injected into the instrument. The analysis was performed using single quadrupole gas chromatography–mass spectrometry (GC-MS) technology and validation was performed according to the guidelines of the German Society of Toxicology and Forensi...

Determination of ethyl glucuronide in human serum by capillary zone electrophoresis and an immunoassay

Journal of Separation Science, 2009

The determination of ethyl glucuronide (EtG), a marker of recent alcohol consumption, in human serum by hyphenation of capillary ITP (CITP) and CZE is reported. For CITP step, 1610 22 M hydrochloric acid adjusted with e-aminocaproic acid (EACA) to pH 4.4 was used as the leading electrolyte, and 1610 22 M nicotinic acid with EACA, pH 4.4, was used as the terminating electrolyte (TE). All electrolytes contained 0.2% hydroxypropylcellulose to suppress electroosmosis. In CITP, EtG was separated from fast serum macrocomponents chloride, phosphate, lactate, and acetate. Zones of microcomponents including EtG that migrated between acetate and nicotinate were forwarded to the second capillary filled with a BGE identical with the TE. Conductivity detection was used in the CITP step. Sensitive detection in the CZE step was performed using indirect spectrophotometric detection at 254 nm. The assay is based on a 1:5 dilution of serum with deionized water and has a concentration LOD for EtG in diluted sample of 9.8610 29 M. The method was used for the determination of EtG in sera of volunteers consuming alcohol.