Neomycin Sulfate and Prednisolone Acetate Ointment
» Neomycin Sulfate and Prednisolone Acetate Ointment contains the equivalent of not less than 90.0 percent and not more than 135.0 percent of the labeled amount of neomycin, and not less than 90.0 percent and not more than 110.0 percent of the labeled amount of prednisolone acetate (C23H30O6).
Packaging and storage Preserve in collapsible tubes or in tight containers, protected from light.
USP Reference standards 11
USP Neomycin Sulfate RS
USP Prednisolone Acetate RS
A: It meets the requirements for neomycin under Thin-Layer Chromatographic Identification Test 201BNP.
B: The retention time of the major peak for prednisolone acetate in the chromatogram of the Assay preparation corresponds to that of the Standard preparation, as obtained in the Assay for prednisolone acetate.
Minimum fill 755: meets the requirements.
Water, Method I 921: not more than 1.0%, 20 mL of a mixture of toluene and methanol (7:3) being used in place of methanol in the titration vessel.
Assay for neomycin Proceed with Ointment as directed in the Assay under Neomycin Sulfate Ointment.
Assay for prednisolone acetate
Mobile phase, Internal standard solution, Standard preparation, and Chromatographic system Prepare as directed in the Assay for prednisolone acetate under Neomycin Sulfate and Prednisolone Acetate Ophthalmic Suspension.
Assay preparation Transfer an accurately weighed portion of Ointment, equivalent to about 1 mg of prednisolone acetate, to a suitable container, add 2.0 mL of Internal standard solution, dilute with water-saturated chloroform to about 35 mL, and shake to dissolve the ointment. Transfer about 5 mL of this solution to a suitable container, and evaporate to dryness. Add about 5 mL of water-saturated chloroform, and sonicate for 5 minutes. Filter, and use the clear solution as the Assay preparation.
Procedure Proceed as directed for Procedure in the Assay for prednisolone acetate under Neomycin Sulfate and Prednisolone Acetate Ophthalmic Suspension. Calculate the quantity, in mg, of prednisolone acetate (C23H30O6) in the portion of Ointment taken by the formula:
0.04C(RU / RS)in which C is the concentration, in µg per mL, of USP Prednisolone Acetate RS in the Standard preparation, and RU and RS are the peak response ratios of prednisolone acetate to betamethasone obtained from the Assay preparation and the Standard preparation, respectively.
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USP35NF30 Page 4031Pharmacopeial Forum: Volume No. 28(4) Page 1165