Simultaneous determination of pyrimethamine, sulfadoxine, mefloquine, and ibuprofen in pharmaceutical formulations by RP-HPLC

A simple and rapid high-performance liquid chromatographic (HPLC) method for simultaneous determination and quantification of pyramethamine, sulfadoxine, mefloquine HCl and ibuprofen was developed. The chromatographic system consisted of a Shimadzu LC-10 AT VP pump, SPD-10 AV VP UV visible detector, and CBM-102 Bus Module integrator. Separation was achieved on a mu Bondapak 125 A, C-18, 10-mu m column at room temperature. The sample was introduced through an injector valve with a 10-mu L sample loop. Acetonitrile/water (50:50, v/v) was used as the mobile phase, with a flow rate of 2 mL/min. The pH was adjusted to 2.6 with phosphoric acid. UV detection was performed at 220 nm. The results obtained showed good agreement with the declared content. Recovery values were from 99.43 to 101.52% for mefloquine (250 mg in Fansimef(A (R)) tablet), from 99.32 to 100.7% for pyrimethamine (25 mg in Fansimef(A (R)) tablet), from 99.29 to 100.21% for sulfadoxine (500 mg in Fansimef(A (R)) tablet), and from 99.96 to 100.04% for ibuprofen (400 mg Dolofen(A (R)) tablet). The proposed method is rapid, accurate, and selective; it may be used for quantitative analysis of pyramethamine, sulfadoxine, mefloquine HCl, and ibuprofen from raw materials, in bulk drugs, and from dosage formulations.