Optimization of hydrophilic interaction liquid chromatographic method for simultaneous determination of cetylpyridinium chloride and benzocaine in lozenges

Abstract

A new Hydrophilic Interaction Liquid Chromatography (HILIC) method was developed for simultaneous determination of cetylpyridinium chloride and benzocaine as active substances in lozenges. Method development included investigation of the influence of the critical chromatographic conditions such as: type of organic modifier, mobile phase strength, ionic strength and pH value of the buffer used in the mobile phase, as well as experimental determination of dominant mechanism of retention. The optimal chromatographic conditions were obtained using bare silica column and a mobile phase consisting of acetonitrile and ammonium formate (50 mM, pH = 4.0) in ratio 80 : 20 V/V. The method was validated in terms of specificity, linearity, accuracy and precision. The validation results indicate that the proposed HILIC method is suitable for quantitative analysis of cetylpyridinium chloride and benzocaine in lozenges.

Keywords

• benzocaine
• cetylpyridinium chloride
• hilic
• lozenges
• retention mechanism