Vidarabine Ophthalmic Ointment
»Vidarabine Ophthalmic Ointment contains not less than 90.0percent and not more than 120.0percent of the labeled amount of anhydrous vidarabine (C10H13N5O4).
Packaging and storage— Preserve in collapsible ophthalmic ointment tubes.
Sterility á71ñ It meets the requirements when tested as directed for Membrane Filtrationunder Test for Sterility of the Product to be Examined.
Minimum fill á755ñ: meets the requirements.
Metal particles— It meets the requirements of the test for Metal Particles in Ophthalmic Ointments á751ñ.
Assay—
Mobile phase ,Standard preparation,and Chromatographic system—Proceed as directed in the Assayunder Vidarabine.
Assay preparation— Transfer an accurately weighed portion of Ophthalmic Ointment,equivalent to about 12mg of vidarabine,to a 100-mLvolumetric flask,add 80mLof water,and heat on a steam bath for 15minutes.Shake,and add 10mLof 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 Procedurein the Assayunder Vidarabine.Calculate the potency,in mg,of C10H13N5O4per g of the Ophthalmic Ointment taken by the formula:
0.5F(rU/rS)(WS/WU),
in which WUis the amount,in mg,of Ophthalmic Ointment taken;and the other terms are as defined therein.
Auxiliary Information— Staff Liaison:William W.Wright,Ph.D.,Scientific Fellow
Expert Committee:(PA7)Pharmaceutical Analysis 7
USP28–NF23Page 2023
Phone Number:1-301-816-8335