Spectrodensitometric determination of clorazepate dipotassium, primidone and chlorzoxazone each in presence of its degradation product.

The present work describes a quantitative thin layer procedure for estimating primidone, clorazepate dipotassium and chlorzoxazone in bulk powders and in dosage forms, each in the presence of its degradation product. The method consists of dissolving the drug in ethanol (for primidone), or methanol (for clorazepate dipotassium and chlorzoxazone) and then spotting this solution on a thin layer of silica gel G254. Quantitation is achieved by comparing the areas under the peaks obtained from scanning the thin layer chromatographic plates in a spectrodensitometer.