A simple, rapid, precise, and stability-indicating reversed-phase high-performance liquid chromatographic (RP-HPLC) method was developed and validated for the simultaneous estimation of Fluorometholone (FML) and Gentamicin (GMC) in marketed ophthalmic formulations. Chromatographic separation was achieved on a C18 column using a mobile phase consisting of 20 mM potassium dihydrogen phosphate (KH₂PO₄) buffer and methanol in the ratio of 20:80 (v/v), delivered at an appropriate flow rate with UV detection. FML and GMC were well resolved with retention times of approximately 1.79 min and 2.23 min, respectively. The developed method showed excellent linearity over the concentration range of 5–25 µg/mL for FML and 1–5 µg/mL for GMC, with correlation coefficients (r²) of 0.9995 and 0.9987, respectively. Validation parameters including system suitability, accuracy, precision, robustness, limit of detection (LOD), and limit of quantification (LOQ) were found to be within acceptable limits as per ICH guidelines. Recovery studies confirmed the accuracy of the method, with mean recovery values close to 100% for both drugs. Forced degradation studies under acidic, alkaline, oxidative, and photolytic conditions demonstrated that the method is stability-indicating, as degradation products did not interfere with the quantification of FML and GMC. The assay results of the marketed ophthalmic formulation were within acceptable limits, confirming the applicability of the method for routine quality control and stability testing. The proposed RP-HPLC method is reliable, economical, and suitable for the simultaneous estimation and stability evaluation of Fluorometholone and Gentamicin in combined ophthalmic dosage forms.
Pradeep Kumar Verma1*, B.K Dubey1, Vivek Singh Thakur1, Deepak Basedia2, Sunil Kumar Shah2 (Sun,) studied this question.