Determination of buprenorphine in raw material and pharmaceutical products using ion-pair formation

Abstract

A simple and sensitive extractive spectrophotometric method has been described for the determination of buprenorphine either in raw material or in pharmaceutical formulations. The developed method is based on the formation of a colored ion-pair complex (1:1 drug/dye) of buprenorphine and bromocresol green (BCG) in buffer pH 3 and extracting in chloroform. The extracted complex shows absorbance maxima at 415 nm. Beer's law is obeyed in the concentration range of 1.32-100.81 μg mL?1. The proposed method has been applied successfully for the determination of drug in commercial sublingual tablets and injectable dosage form. No significant interference was observed from the excipients commonly used as pharmaceutical aids with the assay procedure.