Stability indicating HPTLC determination of pimozide in bulk and pharmaceutical dosage form

A simple, selective, precise and stability indicating high-performance liquid chromatographic method was developed and validated for the determination of pimozide in bulk and pharmaceutical dosage form. The method employed aluminium plates precoated with silica gel 60F-254 as the stationary phase. The solvent system consisted of toluene:acetone:ammonia (5:5:0.1 v/v/v). Compact spot was observed with Rf value 0.55±0.0052. Densitometric analysis of pimozide was carried out in the reflectance mode at 285 nm. Good linear relationship was obtained in the concentration range 80 to 360 ng/spot. The method was validated for specificity, accuracy, precision and robustness. The limit of detection and quantification were 8.855 ng/spot and 26.834 ng/ spot, respectively. Pimozide was subjected to acid and alkali hydrolysis, oxidation, photolysis and thermal degradation. The drug undergoes degradation under acid and base. The proposed HPTLC method can be applied for identification and quantitative determination of pimozide in bulk and tablet dosage form.