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Vidarabine Ophthalmic Ointment
» Vidarabine Ophthalmic Ointment contains not less than 90.0 percent and not more than 120.0 percent of the labeled amount of anhydrous vidarabine (C10H13N5O4).
Packaging and storage— Preserve in collapsible ophthalmic ointment tubes.
Sterility 71— It meets the requirements when tested as directed for Membrane Filtration under Test for Sterility of the Product to be Examined.
Minimum fill 755: meets the requirements.
Metal particles— It meets the requirements of the test for Metal Particles in Ophthalmic Ointments 751.
Residual solvents 467: meets the requirements.
(Official January 1, 2007)
Assay—
Mobile phase , Standard preparation, and Chromatographic system—Proceed as directed in the Assay under Vidarabine.
Assay preparation— Transfer an accurately weighed portion of Ophthalmic Ointment, equivalent to about 12 mg of vidarabine, to a 100-mL volumetric flask, add 80 mL of water, and heat on a steam bath for 15 minutes. Shake, and add 10 mL of n-heptane to the hot suspension. Swirl, and cool to room temperature. Remove the n-heptane layer, and discard it. Dilute the aqueous phase with water to volume, and mix.
Procedure— Proceed as directed for Procedure in the Assay under Vidarabine. Calculate the potency, in mg, of C10H13N5O4 per g of the Ophthalmic Ointment taken by the formula:
0.5F(rU / rS)(WS / WU),
in which WU is the amount, in mg, of Ophthalmic Ointment taken; and the other terms are as defined therein.
Auxiliary Information— Staff Liaison : Brian D. Gilbert, Ph.D., Scientist
Expert Committee : (MDANT05) Monograph Development-Antibiotics
USP29–NF24 Page 2252
Phone Number : 1-301-816-8223