Determination of ethyl glucuronide in human serum by capillary zone electrophoresis and an immunoassay
Autor: | Balthasar Jung, Wolfgang Thormann, Jitka Caslavska |
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Rok vydání: | 2009 |
Předmět: |
Adult
Male Adolescent Alcohol Drinking Filtration and Separation Glucuronates Sensitivity and Specificity Analytical Chemistry chemistry.chemical_compound Young Adult Capillary electrophoresis Ethyl glucuronide Blood serum medicine Protein precipitation Humans Sample preparation Solid phase extraction Immunoassay Chromatography medicine.diagnostic_test Electrophoresis Capillary Reproducibility of Results Middle Aged chemistry Female Quantitative analysis (chemistry) |
Zdroj: | Journal of separation science. 32(20) |
ISSN: | 1615-9314 |
Popis: | Ethyl glucuronide (EtG) is a marker of recent alcohol consumption. For the optimization of the analysis of EtG by CZE with indirect absorbance detection, the use of capillaries with permanent and dynamic wall coatings, the composition of the BGE, and various sample preparation procedures, including dilution with water, ultrafiltration, protein precipitation, and SPE, were investigated. Two validated screening assays for the determination of EtG in human serum, a CZE-based approach and an enzyme immunoassay (EIA), are described. The CZE assay uses a coated capillary, 2,4-dimethylglutaric acid as an internal standard, and a pH 4.65 BGE comprising 9 mM nicotinic acid, epsilon-aminocaproic acid and 10% v/v ACN. Proteins are removed via precipitation with ACN prior to analysis and the LOQ is 0.50 mg/L. The EIA is based upon commercial reagents which are promoted for the determination of urinary EtG. Krebs-Ringer solution containing 5% BSA is used as a calibration matrix. All samples are ultrafiltered prior to analysis of the ultrafiltrate on a Mira Plus analyzer. Assay calibration ranged between 0 and 2 mg/L and the upper reference limit was determined to be 0.05 mg/L. Both assays proved to be suitable for the analysis of samples from different individuals. For EtG levels above 0.50 mg/L, good agreement was observed for the comparison of the results of the two methods. |
Databáze: | OpenAIRE |
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