ISSN 2321-807X 839 | Page December 13, 2013 Kinetic and Conventional Spectrophotometric Determination of Bumadizone in its Tablets via Oxidative Coupling with 3-Methyl-2- Benzothiazolinone Hydrazone M. I. Walash, F. Belal, M. M. Tolba, M. I. Halawa* Department of Analytical Chemistry, Faculty of Pharmacy, University of Mansoura , 35516, Mansoura, Egypt. mwalash@yahoo.com. Department of Analytical Chemistry, Faculty of Pharmacy, University of Mansoura , 35516, Mansoura, Egypt. ffbelal@yahoo.com. Department of Analytical Chemistry, Faculty of Pharmacy, University of Mansoura , 35516, Mansoura, Egypt. manar2kareem@yahoo.com. Department of Analytical Chemistry, Faculty of Pharmacy, University of Mansoura , 35516, Mansoura, Egypt. m_halawa88@hotmail.com. Abstract: Two simple, sensitive and accurate spectrophotometric methods have been developed for the determination of bumadizone in bulk drug and its tablets. Both methods based on the oxidative coupling reaction with 3-methyl-2- benzothiazolinone hydrazone hydrochloride (MBTH) and measuring the absorbance of the developed colors by direct or kinetic spectrophotometric method. Upon treatment of a mixture of the chromogenic reagent and drug with cerium (IV) ammonium sulfate (method I) or ferric chloride (method I), a red or violet color was developed immediately or after 30 minutes measurable at 557 nm for method I or II, respectively. The absorbance-concentration plots were rectilinear over the ranges of 1-10 μg/mL (r = 0.9999) for method I and 2-16 μg/mL (r = 0.9998) for method II. The detection limits were 0.15 and 0.27 μg/mL & the quantitation limits were 0.46 and 0.84 μg/mL for methods I and II, respectively. Different experimental parameters affecting the development and stability of the reactions products were studied and optimized. The proposed methods were applied successfully to the determination of bumadizone in its tablets, and the results obtained were in good agreement with those obtained using a comparison method. Key words: Bumadizone; MBTH, Kinetic; Oxidative coupling; Pharmaceutical analysis. Council for Innovative Research Peer Review Research Publishing System Journal: Journal of Advances in Chemistry Vol. 5, No. 1 editor@cirworld.com www.cirworld.com , member.cirworld.com