» Betaxolol Tablets contain an amount of Betaxolol Hydrochloride equivalent to not less than 90.0 percent and not more than 110.0 percent of the labeled amount of betaxolol hydrochloride (C18H29NO3·HCl).
Packaging and storage Preserve in tight containers.
Labeling Label the Tablets to state both the content of the betaxolol active moiety and the content of betaxolol hydrochloride used in formulating them.
Identification The retention time of the major peak in the chromatogram of the Assay preparation corresponds to that in the chromatogram of the Standard preparation, as obtained in the Assay.
Medium: 0.01 N hydrochloric acid; 500 mL.
Apparatus 2: 50 rpm.
Time: 30 minutes.
Procedure Determine the amount of C18H29NO3·HCl dissolved by employing UV absorption at the wavelength of maximum absorbance at about 274 nm on filtered portions of the solution under test in comparison with a Standard solution having a known concentration of USP Betaxolol Hydrochloride RS in the same Medium. A 5-cm pathlength cell may be used for lower dosage levels.
Tolerances Not less than 80% (Q) of the labeled amount of C18H29NO3·HCl is dissolved in 30 minutes.
Uniformity of dosage units 905: meet the requirements.
Procedure for content uniformity Place 1 Tablet in a volumetric flask of appropriate size to obtain a concentration, based on the labeled amount of betaxolol hydrochloride per Tablet, of about 0.1 mg per mL when diluted. Add an amount of 0.1 N hydrochloric acid equal to about 70% of the volume of the flask, shake by mechanical means until dissolved, dilute with 0.1 N hydrochloric acid to volume, and mix. Filter the mixture, discarding the first 20 mL of the filtrate. Concomitantly determine the absorbances of the clear filtrate and of a Standard solution of USP Betaxolol Hydrochloride RS in 0.1 N hydrochloric acid having a known concentration of about 0.1 mg per mL, in 1-cm cells, at the wavelength of maximum absorbance at about 274 nm, using 0.1 N hydrochloric acid as the blank. Calculate the quantity, in mg, of betaxolol hydrochloride (C18H29NO3·HCl) in the Tablet taken by the formula:
(CV)(AU / AS)in which C, is the concentration, in mg per mL, of USP Betaxolol Hydrochloride RS in the Standard solution; V is the volume, in mL, of 0.1 N hydrochloric acid used to dissolve the Tablet; and AU and AS are the absorbances of the solution from the Tablet and the Standard solution, respectively.
Mobile phase Prepare a filtered mixture of 0.025 M pH 6.0 ammonium phosphate buffer, acetonitrile, and methanol (35:35:30). Mix, and degas under vacuum while stirring. Make adjustments if necessary (see System Suitability under Chromatography 621).
Diluent Prepare a mixture of acetonitrile and water (1:1).
Standard preparation Dissolve an accurately weighed quantity of USP Betaxolol Hydrochloride RS in Diluent to obtain a solution having a known concentration of about 2 mg per mL.
Assay preparation Dissolve not fewer than 20 Tablets in an appropriate accurately measured volume of Diluent so that the final concentration, based on the labeled amount per Tablet, is about 2 mg of betaxolol hydrochloride per mL. Sonicate until the Tablets are disintegrated. Cool to room temperature, dilute with Diluent to volume, mix, and filter. Use the clear filtrate as the Assay preparation.
Chromatographic system (see Chromatography 621) The liquid chromatograph is equipped with a 273-nm detector and a 4.6-mm × 15-cm column that contains packing L1. The flow rate is about 1.5 mL per minute. Chromatograph the Standard preparation, record the chromatogram, and measure the peak response as directed for Procedure: the tailing factor is not more than 3.0, and the relative standard deviation for replicate injections is not more than 2.0%.
Procedure Separately inject equal volumes (about 10 µL) of the Standard preparation and the Assay preparation, record the chromatograms, and measure the responses for the major peaks. Calculate the quantity, in mg, of betaxolol hydrochloride (C18H29NO3·HCl) in each Tablet taken by the formula:
(CV/N)(rU / rS)in which C is the concentration, in mg per mL, of USP Betaxolol Hydrochloride RS in the Standard preparation; V is the volume of Diluent used to dissolve the Tablets; N is the number of Tablets taken; and rU and rS are the betaxolol peak responses obtained from the Assay preparation and the Standard preparation, respectively.
Auxiliary Information Please check for your question in the FAQs before contacting USP.Chromatographic Column
USP32NF27 Page 1668Pharmacopeial Forum: Volume No. 27(4) Page 2703
Chromatographic columns text is not derived from, and not part of, USP 32 or NF 27.