Analysis of blood and urine samples from Macaca mulata for pyronaridine by high-performance liquid chromatography with electrochemical detection.

We describe a high-performance liquid chromatographic method with electrochemical detection for quantifying pyronaridine in rhesus monkey (Macaca mulata) blood and urine samples. The detection limit is 20 ng/ml at a signal-to-noise ratio of 4 in 0.5-ml samples of blood or urine. Blood analysis includes a liquid-liquid extraction and a subsequent solid-phase extraction that removes an interferent present in blood. For urine, a back-extraction is substituted for the solid-phase extraction step. The method uses an analogue of amodiaquine as internal standard, a 10-microns rigid macroporous styrene-divinylbenzene copolymer column and a mobile phase of 1% (v/v) triethylamine in methanol-water (34:66, v/v). The method was applied to samples of blood and urine from a monkey after a single intramuscular dose of pyronaridine tetraphosphate (160 mg as base).