Separation and determination of ketoprofen, methylparaben and propylparaben in pharmaceutical preparation by micellar electrokinetic chromatography.

Simple micellar electrokinetic chromatographic (MEKC) method was developed for the determination of ketoprofen as the active substance and methylparaben and propylparaben as preservatives in a semisolid pharmaceutical preparation. Separation was carried out with a fused silica capillary and UV detection at 200nm. Optimized background electrolyte was 50mM tricine buffer containing 30mM sodium dodecyl sulfate as surfactant and 15% (v/v) of methanol. Single separation took about 13min. No statistically significant differences were found when comparing the results with those of RP-HPLC method reported in literature.