Chemometric Approach for RP-HPLC Determination of Azithromycin, Secnidazole, and Fluconazole Using Response Surface Methodology

This paper demonstrates a chemometric-assisted RP-HPLC method for the simultaneous determination of azithromycin, secnidazole, and fluconazole using water:methanol (63:37% v/v) as mobile phase at a flow rate of 1.2mL center dot min(-1). The separation of the three drugs was achieved on an Xterra RP-18 column (250x4.6mm ID, 5 mu M) and the detection of the eluents was realized on a diode array detector at 210nm wavelength. The combined effects of % methanol (organic phase) and flow rate, each at three levels influencing the chromatographic efficiency were investigated and optimized employing central composite design. Under the optimal condition, the percent relative standard deviations for precision study were in the range of 0.2-0.7% and 0.5-1.2% for standard and formulation, respectively. The limits of detection were 12.5, 0.62, and 1.7 mu g center dot mL(-1) and limits of quantification were found 37.5, 1.86, and 5.1 mu g center dot mL(-1) for azithromycin, secnidazole, and fluconazole, respectively. Consequently, the method has been effectively applied to their direct determination in the commercial formulation (combi-kit).