Benzatropine Tablets
Action and use
Anticholinergic.
Definition
Benzatropine Tablets contain Benzatropine Mesilate.
Content of benzatropine mesilate, C21H25NO,CH4O3S
90.0 to 110.0% of the stated amount.
Identification
Tests
Tropine
Carry out the method for thin-layer chromatography, Appendix III A, using the following solutions.
15 volumes of 13.5m ammonia and 75 volumes of ethanol (96%).
Any spot corresponding to tropine in the chromatogram obtained with solution (1) is not more intense than the spot in the chromatogram obtained with solution (2).
Uniformity of content
Tablets containing less than 2 mg and/or less than 2% w/w of Benzatropine Mesilate comply with the requirement stated under Tablets using the following method of analysis.
Carry out the method for liquid chromatography, Appendix III D, using the following solutions.
35 volumes of octylamine phosphate buffer pH 3.0 and 65 volumes of acetonitrile.
Calculate the content of C21H25NO,CH4O3S in each tablet using the declared content of C21H25NO,CH4O3S in benzatropine mesilate BPCRS.
Assay
Weigh and powder 30 tablets. To a quantity of the powder containing 50 mg of Benzatropine Mesilate add 50 mL of water and shake for 15 minutes. Add 10 mL of a 50% w/v solution of sodium hydroxide and an excess of sodium chloride and extract with successive quantities of 50, 25, 25 and 25 mL of ether. Extract the combined ether layers with successive quantities of 25, 25, 25 and 15 mL of 2m hydrochloric acid, dilute the combined extracts to 100 mL with 2m hydrochloric acid, mix and filter if necessary. Measure the absorbance of the resulting solution at the maximum at 258 nm, Appendix II B. Calculate the content of C21H25NO,CH4O3S from the absorbance obtained by repeating the operation using 50 mg of benzatropine mesilate BPCRS in place of the powdered tablets and from the declared content of C21H25NO,CH4O3S in benzatropine mesilate BPCRS.