Determination of diminazene in plasma by high-performance liquid chromatography.

An analytical method is described for determining diminazene levels in plasma of cattle. Diminazene is reduced to 4-aminobenzamidine which is extracted and assayed by high-performance ion pair reverse phase partition chromatography. 3,4-Dimethoxybenzamidine served as an internal standard. Diminazene levels as low as 0.1 microgram per ml were detected.