VALIDATED THIN-LAYER CHROMATOGRAPHY/DENSITOMETRY METHOD FOR THE ANALYSIS OF ANTI-ALZHEIMER DRUG IN BULK AND IN CAPSULE FORMULATION

A simple, sensitive and precise Thin-Layer Chromatography (TLC)/Densitometry method has been developed for estimation of Rivastigmine hydrogen tartrate [RVT] in bulk and in capsule formulation. The chromatographic separation was accomplished on aluminium backed precoated silica gel 60 F-254 as the stationary phase using n-Hexane: Ethyl acetate: triethylamine (1.5: 8.5: 0.3 v/v) as mobile phase. The R-F value was observed to be 0.46 +/- 0.02 for RVT when the sports were analyzed densitometrically at 213 nm. The method was linear in the range of 1000-6000 ng band(-1) with coefficient correlation value 0.9990. RVT was subjected to acid, alkali hydrolysis, oxidation, dry heat degradation and photo degradation. The degraded product peaks were well resolved from the pure drug peak with significant difference in their R-F values. Analysis of drug was performed in the presence of degraded samples. The proposed method validated for linearity, accuracy, precision and robustness. The developed TLC-densitometric method can be used as an alternative method for the precise assay of rivastigmine hydrogen tartrate in capsules form because it fulfils the validation criteria of an analytical method designated for quantity control of pharmaceutical preparations.