A spectrophotometric method for the determination of buclizine hydrochloride using the charge-transfer spectrum of buclizine iodine complex

A simple and sensitive spectrophotometric method is described for the determination of buclizine hydrochloride in bulk and tablets form. The method is based on the formation Of charge-transfer complex between buclizine,as n-donor, and iodine, as a acceptor, which measured spectrophotometrically at 295 and 355 nm. A Job's plot indicated a 1:1 complex between the drug and iodine and Beer's law was obeyed in a concentration range of 4-30 mu g ml(-1). A more detailed investigation of the complex was made with respect to its association constant and the free energy change. The method is simple and sensitive and has been applied successfully to the analysis of laboratory-made tablets without any interference from the tablet excipients. To validate the method, the results obtained were compared statistically with a newly developed UV-derivative spectrophotometric method. The charge-tra nsf er method was favored due to its higher sensitivity, cheap coast and available equipments.