QUANTITATIVE-ANALYSIS OF CHLORPHENIRAMINE MALEATE IN COUGH AND COLD DRUGS BY ION-PAIR HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY FOR THE SIMULTANEOUS DETERMINATION OF CHLORPHENIRAMINE AND MALEATE

A simple, rapid and convenient chromatographic method, which permits t he simultaneous determination of chlorpheniramine (CP) and maleate (MA ), recently developed by the authors was applied to the analysis of ch lorpheniramine maleate (CPM) in cough and cold drugs. In this method, a Capcell Pak C-8 column and an isocratic mobile phase containing 15% methanol, 50 mM KH2PO4 and 5 mM tetra-n-butylammonium phosphate as an ion-pair reagent were used. By using the mobile phase adjusted to pH 3 .0 with orthophosphoric acid, fumaric acid, MA, CP, acetaminophen (par acetamol), caffeine, and m- and p-hydroxybenzoic acid as candidates fo r an internal standard were eluted separately within 17 min. Detection was carried out with UV detector at 215 nm. Under the same conditions , five other antihistamines analogous to CPM were also separated. The calibration graphs for CP and MA showed good linearity in the range of 0.5-10 nmol (0.195-3.9 mu g) per 20 mu l injection, respectively. The proposed method was successfully applied to the simultaneous determin ation of CP and MA, i.e., CPM analysis, in commercial cough and cold d rugs which pharmaceutical forms were tablet, granule and syrups.