Spectrophotometric Estimation of Betaxolol Spectrophotometric Estimation of Betaxolol Spectrophotometric Estimation of Betaxolol Spectrophotometric Estimation of Betaxolol Spectrophotometric Estimation of Betaxolol Hydrochloride in Bulk Powder and its Dosage Forms Hydrochloride in Bulk Powder and its Dosage Forms Hydrochloride in Bulk Powder and its Dosage Forms Hydrochloride in Bulk Powder and its Dosage Forms Hydrochloride in Bulk Powder and its Dosage Forms

A simple and sensitive spectrophotometric method has been developed for determination of betaxolol hydrochloride in bulk powder, and its pharmaceutical dosage forms. In the proposed method, betaxolol is oxidized with sodium periodate, to liberate formaldehyde, which is determined in situ, using acetyl acetone in the presence of ammonium acetate. A yellow coloured chromogen was obtained having absorption maxima at 405 nm. The method is found to be linear in the concentration range of 5-30 µg/ml, with a regression co-efficient of 0.9997. No significant difference was found between the proposed method and official method, when one tailed and two tailed t-test are applied. Various reaction parameters such as concentration of sodium hydroxide and sodium periodate, time required for oxidation, reagent concentration, and time for maximum colour intensity were optimized. The method was validated, and can be used successfully to assay betaxolol in bulk powder, and its pharmaceutical dosage forms viz. ophthalmic solutions. Betaxolol, potent adrenergic blocker 1 is structurally related to metoprolol. Chemically 2-3 it is 1-(4-(cyclopropylmethoxy) ethyl) phenoxy)-3-isopropylaminopropan-2-ol hydrochloride. It is used in glaucoma and ocular hypertension, as one drop of 0.5% solution twice daily 4 . The recommended starting dosage for mild to moderate hypertension is 10 to 20 mg per day in a single oral dose 5 . A dose of 10 mg per day should be used in elderly and patients with severe renal diseases. The ophthalmic solution of betaxolol hydrochloride is official in the United States Pharmacopoeia, and assayed by high performance liquid chromatographic method 3 . Literature survey reveals that betaxolol is estimated in pharmaceuticals and biological fluids by HPLC 6-12 and spectropotometric methods 13 . In the proposed investigation, an attempt has been made to develop a simple, economical, accurate, and reproducible spectrophotometric method for estimation of betaxolol in pharmaceutical formulation. In the proposed method, betaxolol hydrochloride is first neutralized with sodium hydroxide, and the librated base is oxidized with sodium periodate to produce formaldehyde 14 . The reaction mixture, on treatment with acetyl acetone in presence of ammonium acetate, gives yellow coloured product having maximum absorbance at 405 nm. The proposed method was successfully applied for