Gas chromatography chemical ionization mass spectrometric analysis of diminazene in plasma

Abstract

A quantitative and sensitive method was developed for the determination of diminazene in plasma. The assay involves the reduction of diminazene to 4‐aminobenzamidine and 4‐hydrazinobenzamidine. The latter is further reduced to give an additional mole of 4‐aminobenzamidine which is extracted, acetylated and condensed with hexafluoroacetylacetone to form a volatile derivative that is subsequently analyzed by gas chromatography chemical ionization mass spectrometry. 4‐Aminobenzylamidine was synthesized and used as an internal standard. The method is reproducible and its sensitivity limit using 1 ml of plasma is 0.1 μg diminazene ml−1. This sensitivity limit is sufficient to detect plasma levels in cattle following therapeutic doses of the drug. Copyright © 1978 Heyden & Son Ltd