Assessment of MEKC suitability for residue drug monitoring on pharmaceutical manufacturing equipment

The suitability of micellar electrokinetic chromatography for the simultaneous trace determination of several compounds (sulfamethoxazole, trimethoprim, sulfanilic acid, sulfanilamide, 3,4,5-trimethoxybenzoic acid and nonoxynol-9) was assessed. The mixture was separated within 14 min at an applied voltage of 22 kV by using 30 mM phosphate electrolyte, containing 10 mM SDS, adjusted to pH 7.8. Under optimized separation conditions acceptable levels of linearity, precision and accuracy were obtained for all compounds. The method could be used as part of a cleaning validation study when assaying trace levels of co-trimoxazole drug, some of its decomposition products and detergent in the swab samples collected from pharmaceutical manufacturing equipment, after cleaning.