Isosorbide Dinitrate Chewable Tablets
» Isosorbide Dinitrate Chewable Tablets contain not less than 90.0 percent and not more than 110.0 percent of the labeled amount of C6H8N2O8.
Packaging and storage— Preserve in well-closed containers.
USP Reference standards 11
USP Diluted Isosorbide Dinitrate RS Click to View Structure
Identification— Chewable Tablets respond to the Identification test under Isosorbide Dinitrate Tablets. Where separation of interferences is required, use the technique given under the Identification test for Isosorbide Dinitrate Extended-release Capsules.
Uniformity of dosage units 905: meet the requirements.
Buffer solution, Mobile phase, Internal standard solution, Standard preparation, and Chromatographic system— Prepare as directed in the Assay under Diluted Isosorbide Dinitrate.
Assay preparation— Weigh and finely powder not fewer than 20 Chewable Tablets. Transfer an accurately weighed portion of the powder, equivalent to about 12.5 mg of isosorbide dinitrate, to a dry, 50-mL volumetric flask, add about 30 mL of Mobile phase, and shake the mixture by hand immediately, to prevent clumping. If clumping persists, disperse with the aid of sonication, or break the aggregates with a stirring rod, or warm on a steam bath while keeping the flask stoppered, or allow the flask to stand until the clumps dissipate. [note—If clumping still continues, discard the mixture, and instead disperse an accurately weighed test portion in 15 mL of a 1 in 10 dilution of Buffer solution in water by heating on a steam bath for 1 hour with frequent shaking, then add 15 mL of methanol. ] Shake for 30 minutes. Add 8.0 mL of Internal standard solution, cool to room temperature, add 8 mL of a 1 in 10 dilution of Buffer solution in water, dilute with Mobile phase to volume, and mix. Pass a portion through a microporous membrane filter.
Procedure— Proceed as directed for Procedure in the Assay under Diluted Isosorbide Dinitrate. Calculate the quantity, in mg, of C6H8N2O8 in the portion of Chewable Tablets taken by the formula:
50C(RU / RS)
in which C is the concentration, in mg per mL, of isosorbide dinitrate from the USP Diluted Isosorbide Dinitrate RS taken for the Standard preparation; and RU and RS are the ratios of the peak responses obtained from the Assay preparation and the Standard preparation, respectively.
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Monograph Sujatha Ramakrishna, Ph.D.
Senior Scientific Liaison
(SM22010) Monographs - Small Molecules 2
Reference Standards RS Technical Services
USP35–NF30 Page 3589
Pharmacopeial Forum: Volume No. 31(5) Page 1376