Assay of Ropinirole Hydrochloride in Pharmaceutical Preparations by Visible Spectrophotometry

Two simple and sensitive direct visible spectrophotometric methods (M₁ and M₂) have been developed for the determination of Ropinirole hydrochloride in bulk and solid dosage forms. These methods are based on the reaction of drug with aromatic aldehydes such as Vanillin or Para dimethyl amino Benzaldehyde (PDAB) in the presence of sulphuric acid in non aqueous medium and formed colored condensation products with an absorption maximum of 560nm for method M₁ and 660nm for method M₂. The Beer's law obeyed in the concentration range of 5-20μg/ml for method M₁ and 25-150μg/ml for method M₂. The proposed methods are validated with respect to accuracy, precision, linearity and limit of detection. The suggested procedures are successfully applied to the determination of the drug in pharmaceutical preparation, with high percentage of recovery, good accuracy and precision. The results of analysis have been validated statistically by repeatability and recovery studies. The results are found satisfactory and reproducible. These methods are applied successfully for the estimation of ropinirole hydrochloride in tablet dosage form without the interference of excipients.