Method development for the chromatographic determination of novocainamide in saliva for acetylator phenotype evaluation in humans

Abstract

A method, involving high-performance liquid chromatography with diode-array detection, was developed for the quantitative determination of novocainamide and its metabolite (N-acetylnovocainamide) in saliva. Chromatographic condition of isocratic elution was established with Discovery C18 column, using mobile phase consisting of acetonitrile and 5 mM phosphate buffer, pH 3.0 (28:72 vol.%), containing ion-pair reagent, 5 mM SDS. The interval of determination of novocainamide and its metabolite, N-acetylnovocainamide in saliva was 0.2 - 10 µg/ mL. Validation of the developed method was carried out on indicators of suitability of chromatographic system, selectivity, accuracy, linearity and reproducibility. The possibility of the application of the developed method was demonstrated for the assessment of individual metabolic phenotypes of acetylation of novocainamide in humans by evaluating the level of novocainamide content in saliva within 6 hours after administering a dose of 250 mg. The concentrations of novocainamide determined in saliva reliably differ for fast and slow acetylators.