title: The homogeneity testing of EtG in hair reference materials: a high-throughput procedure using GC-NCI-MS.
abstract: The validation of a robust quantification procedure for EtG in hair using GC-NCI-MS is presented. Aqueous extraction is followed by complete lyophylization of the extract and derivatization with pentafluoropropionic anhydride (PFPA) under controlled temperature and duration. Clean-up of extracts was dispensable and standard single quadrupole MS displayed sufficient selectivity and sensitivity. The method displayed a wide linearity range and enabled LOD of 0.68 pg/mg, LOQ of 2.4 pg/mg, and precision below 8.12%. Since EtG was seen to display prolonged stability in the aqueous extracts and after derivatization with PFPA this straightforward procedure allows a routine throughput of large quantities of samples with little proneness to procedural scatter of results. The method was applied to demonstrate the homogeneity of two hair reference materials with mean EtG contents of 8.48 pg/mg and 22.0 pg/mg. Aside from the application in homogeneity studies of hair reference materials predominantly in the concentration range of 10-50 pg/mg the method was also designed for daily routine quantification of real-world sample with regard to drinking behavior assessment.
authors: Division of Trace Analysis, Department of Analytical Chemistry, Federal Institute for Materials Research and Testing (BAM), Richard-Willstätter-Strasse 11, 12489 Berlin, Germany.
authors: Bettina
authors: B
authors: Mönch
authors: Roland
authors: R
authors: Becker
authors: Christian
authors: C
authors: Jung
authors: Irene
authors: I
authors: Nehls
mesh_terms: D000704:Analysis of Variance; D005466:Fluorocarbons; D053593:Forensic Toxicology; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D005965:Glucuronates / Q000032:analysis*; D006197:Hair / Q000737:chemistry*; D006801:Humans; D057230:Limit of Detection; D016014:Linear Models; D013048:Specimen Handling
chemical_list: D005466:Fluorocarbons; D005965:Glucuronates; C068048:pentafluoropropionic anhydride; C093924:ethyl glucuronide