Application of a stability-indicating TLC method for the quantitative determination of Levocetirizine in pharmaceutical dosage forms

A sensitive, selective, precise and stability-indicating thin layer chromatographic method of analysis for Levocetirizine both as a bulk drug and in formulation was developed and validated. The method employed TLC aluminium plates precoated with silica gel 60 F-254 as the stationary phase and the solvent system consisted of ethyl acetate: methanol: ammonia (9: 2.5: 1.5 v/v/v). This system was found to give compact spots for Levocetirizine (Rf value of 0.50 ± 0.02). Levocetirizine was subjected to acid and alkali hydrolysis, oxidation, photo and neutral degradation. The peak of the degradation product was well resolved from the pure drug and had significantly different Rf value. Densitometric analysis of Levocetirizine was carried out in the absorbance mode at 230 nm. The linear regression analysis data for the calibration plots showed a good linear relationship over the concentration range of 200-1200 ng/spot. The mean values of the correlation coefficient, slope and intercept were 0.9904 ± 1.53, 2.8899 ± 0.998 and 802.6 ± 0.982 respectively. The method was validated for precision, robustness and recovery. The limit of detection (LOD) and limit of quantitation (LOQ) was 100 and 200 ng/spot respectively. Statistical analysis showed that the method is repeatable and selective for the estimation of Levocetirizine. Since the method can separate the drug from its degradation products, it can be used to monitor stability. Keywords: Degradation; Levocetirizine; TLC; stability-indicating.