A: It meets the requirements for neomycin under Thin-Layer Chromatographic Identification Test á201BNPñ.

B: The retention time of the major peak for prednisolone acetate in the chromatogram of the Assay preparationcorresponds to that of the Standard preparation,as obtained in the Assay for prednisolone acetate.

Mobile phase,Internal standard solution,Standard preparation,and Chromatographic system— Prepare as directed in the Assay for prednisolone acetateunder Neomycin Sulfate and Prednisolone Acetate Ophthalmic Suspension.

Assay preparation— Transfer an accurately weighed portion of Ointment,equivalent to about 1mg of prednisolone acetate,to a suitable container,add 2.0mLof Internal standard solution,dilute with water-saturated chloroform to about 35mL,and shake to dissolve the ointment.Transfer about 5mLof this solution to a suitable container,and evaporate to dryness.Add about 5mLof water-saturated chloroform,and sonicate for 5minutes.Filter,and use the clear solution as the Assay preparation.

Procedure— Proceed as directed for Procedurein the Assay for prednisolone acetateunder 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: in which Cis the concentration,in µg per mL,of USP Prednisolone Acetate RSin the Standard preparation,and RUand RSare the peak response ratios of prednisolone acetate to betamethasone obtained from the Assay preparationand the Standard preparation,respectively.