Optimized and validated spectrophotometric determination of two antifungal drugs in pharmaceutical formulations using an ion-pair complexation reaction

Simple, rapid, cost-effective, sensitive and extractive spectrophotometric methods were developed for the determination of two antifungal drugs (i.e., sertaconazole nitrate (SER) and miconazole nitrate (MCO)) in pure and dosage forms. The methods are based on the formation of ion-pair complexes between the drugs and acid dyes (i.e., bromocresol purple (BCP), bromophenol blue (BPB) and methyl orange (MO)) in acidic buffer solutions. The formed complexes were extracted with chloroform and measured at 410, 416 and 427 nm for SER and at 408, 415 and 426 nm for MCO using BCP, BPB and MO, respectively. The analytical parameters and their effects on the reported systems were investigated. Beer's law was obeyed in the 1.0–20 and 1.0–24 μg mL−1 ranges for SER and MCO, respectively. The composition of the ion pairs was determined to be 1:1. The molar absorptivity, Sandell sensitivity, limits of detection and limits of quantification were calculated. Other method validation parameters, such as precision, accuracy, robustness, ruggedness and selectivity, were satisfactory. The proposed methods have been successfully applied for the analysis of the studied drugs in their pure and dosage forms. Statistical comparison of the results with the reference methods indicated excellent agreement and no significant difference in accuracy and precision.