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Neomycin Sulfate and Dexamethasone Sodium Phosphate Cream
» Neomycin Sulfate and Dexamethasone Sodium Phosphate Cream contains the equivalent of not less than 90.0 percent and not more than 135.0 percent of the labeled amount of neomycin, and the equivalent of not less than 90.0 percent and not more than 110.0 percent of the labeled amount of dexamethasone phosphate (C22H30FO8P).
Packaging and storage— Preserve in collapsible tubes or in tight containers.
Identification—
A: It meets the requirements for neomycin under Thin-Layer Chromatographic Identification Test 201BNP.
B: The Assay preparation, prepared as directed in the Assay for dexamethasone phosphate, meets the requirements for the Identification test under Dexamethasone Sodium Phosphate Cream.
Minimum fill 755: meets the requirements.
Residual solvents 467: meets the requirements.
(Official January 1, 2007)
Assay for neomycin— Proceed with Cream as directed in the Assay under Neomycin Sulfate Cream.
Assay for dexamethasone phosphate—
Alcohol–aqueous phosphate buffer, 0.05 M Phosphate buffer, Mobile phase, Standard preparation, and Chromatographic system— Prepare as directed in the Assay under Dexamethasone Sodium Phosphate Cream.
Assay preparation— Using an accurately weighed portion of Cream, prepare as directed in the Assay under Dexamethasone Sodium Phosphate Cream.
Procedure— Proceed as directed for Procedure in the Assay under Dexamethasone Sodium Phosphate Cream. Calculate the quantity, in mg, of dexamethasone phosphate (C22H30FO8P) in the portion of Cream taken by the formula:
0.1C(rU / rS).
Auxiliary Information— Staff Liaison : Brian D. Gilbert, Ph.D., Scientist
Expert Committee : (MDANT05) Monograph Development-Antibiotics
USP29–NF24 Page 1494
Pharmacopeial Forum : Volume No. 28(4) Page 1154
Phone Number : 1-301-816-8223