Determination of 17β-estradiol in bovine plasma: development of a highly sensitive technique by ion trap gas chromatography–tandem mass spectrometry using negative chemical ionization

✍ Scribed by Giancarlo Biancotto; Roberto Angeletti; Pietro Traldi; Massimiliano Silvestri; Mauro Saccon; Federico Guidugli

• Publisher: John Wiley and Sons
• Year: 2002
• Tongue: English
• Weight: 141 KB
• Volume: 37
• Category: Article
• ISSN: 1076-5174
• DOI: 10.1002/jms.397

✦ Synopsis

Abstract

A novel approach to the determination of 17β‐estradiol in bovine plasma is presented. The observed enhanced sensitivity is gained by the application of tandem mass spectrometry (MS) fragmentation to a stable, well characterized negative ion produced by chemical ionization (methane as reagent gas). A specific derivatizing reactant is employed (pentafluorobenzyl bromide), combined with bis‐trimethylsilyltrifluoroacetamide, to favor the formation of a diagnostic precursor negative ion. Plasma samples are purified through a C18 solid phase extraction column and derivatized before gas chromatography–MS analysis. The accuracy and the precision of the method, tested over a set of spiked samples, were satisfactory. The limit of detection was found to be 5 pg ml^−1^ and the limit of quantification was fixed at 20 pg ml^−1^. The fragmentation pattern is fully explained and the method is applicable for the official analysis of bovine plasma for the detection of 17β‐estradiol according to the European criteria 256/93 and to the draft SANCO/1805/2000 rev. 3. The quantification of incurred positive samples was performed according to the proposed procedure and compared with the results obtained by standardized radio immuno assay; the estimated concentrations were significantly similar. Copyright © 2002 John Wiley & Sons, Ltd.