ABSTRACT

Two simple, rapid, precise, accurate and robust (HPTLC and RP-HPLC) methods have been established for simultaneous determination of ofloxacin and prednisolone acetate in its combined ophthalmic formulation. HPTLC separation of two drugs was accomplished on a HPTLC aluminum-backed layer of silica gel 60 F254 using n-butanol: methanol: ammonia (60:10:30% V/V/V) as a mobile phase. The densitometric scanning was performed at 275 nm which showed Rf 0.43 for ofloxacin and 0.78 for prednisolone acetate, respectively. RP-HPLC separation of the two drugs was achieved on LC-GC Qualisil BDS C-18 column using mobile phase methanol: acetonitrile: 0.02 M potassium dihydrogen ortho-phosphate anhydrous (50:15:35% V/V/V), pH adjusted to 4.5 with triethylamine. Detection of both drugs was done at 275 nm. Aspirin was used as an internal standard (IS). The retention time for ofloxacin, prednisolone acetate and aspirin (IS), was found to be 4.36 min. and 6.60 min and 3.55 min, respectively. The proposed methods were successfully applied for the determination of both drugs in bulk and in combined ophthalmic formulation. Assay of both these methods were compared using student t-test.