Stability indicating thin-layer chromatographic determination of fexofenadine hydrochloride as bulk drug: Application to forced degradation study

The objective of present work was to develop a validated stability indicating high performance thin layer chromatographic method (HPTLC) for estimation of fexofenadine hydrochloride. The stationary phase used was precoated silica gel aluminium plates 60 F-254 with 250 μm thickness. The mobile phase used for separation was toluene: ethyl acetate: methanol: ammonia (30%) (0.5: 7: 3: 0.6 v/v/v/v) gave a resolved peak at (Rf value of 0.27 ± 0.02). The densitometric quantification was carried out at 220 nm. Fexofenadine hydrochloride was subjected to acid and alkali hydrolysis, oxidation, dry heat treatment and photo degradation. The drug was found to degrade in acidic, alkaline, oxidative and dry heat conditions, but was found to be stable in photolytic conditions. All the peaks of degraded products were separated from the standard drug with significantly different (Rf values as 0.03± 0.02 in acid, 0.06± 0.02 and 0.84± 0.02 in base, 0.06± 0.02 , 0.62± 0.02, 0.64± 0.02 and 0.82± 0.02 in hydrogen peroxide, 0.02± 0.02, 0.68± 0.02 in dry heat conditions). The developed method can effectively separate the drug from its degradation products under accelerated degradation studies, it can be routinely employed as stability indicating method for fexofenadine hydrochloride