A Validated HPLC‐PDA Method for Simultaneous Determination of Metronidazole, Miconazole Nitrate, Fluconazole, and Tinidazole: Application in Bulk and in Different Pharmaceutical Dosage Forms

ABSTRACT In this report, an HPLC‐PDA method was developed for the simultaneous detection of fluconazole, tinidazole, metronidazole, and miconazole nitrate in single and combined‐dose tablets. This method systematically investigates important parameters to enhance separation and quantification using HPLC‐PDA. Chromatographic separation was achieved on a Zorbax SB C8 column using a mobile phase mixture of water and isopropyl alcohol (75:25 v/v) at a flow rate of 0.8 mL/min, with a column oven temperature of 35°C, and detection at 210 nm. The asymmetry factors of 1.32, 0.95, 1.06, and 1.31 were observed for metronidazole, miconazole nitrate, fluconazole, and tinidazole, respectively, all within acceptable limits. The run time was less than 8 min. The calibration curve exhibited linearity within the range of 45–135 µg/mL for metronidazole, fluconazole, tinidazole, and 50–300 µg/mL for miconazole nitrate. The method was validated for linearity, precision, accuracy, and specificity. The accuracy results reveal mean recoveries of 100.3%, 100.1%, 99.8%, and 100.6% obtained for metronidazole, miconazole nitrate, fluconazole, and tinidazole, respectively. The method was successfully implemented for the quantitative determination of marketed formulations. The advanced assessment of GAPI, Blue Applicability Grade Index (BAGI), Red Analytical Performance Index (RAPI), Analytical Eco‐Scale, and AGREE demonstrates its increased environmental friendliness and sustainability.