Confirmation of diminazene diaceturate in bovine plasma using electrospray liquid chromatography–mass spectrometry

Diminazene diaceturate is used as a trypanocide for cattle in tropical regions. This paper describes a LC–MS n method to confirm the presence of diminazene in bovine plasma. Bound diminazene in plasma samples was freed with dilute phosphoric acid, then concentrated on a bonded C 18 SPE cartridge. The LC–MS n method utilized electrospray ionization coupled with an ion trap mass spectrometer. Ions observed in MS 2 and MS 3 product ion spectra, as well as those from the MS 1 spectrum, were monitored. The method was validated with plasma samples fortified with diminazene diaceturate (4–100 ng/mL). Diminazene was confirmed in samples fortified with diminazene diaceturate at levels of 6.4 ng/mL or higher.