Neomycin and Polymyxin B Sulfates and Hydrocortisone Otic Suspension
» Neomycin and Polymyxin B Sulfates and Hydrocortisone Otic Suspension is a sterile suspension containing the equivalent of not less than 90.0 percent and not more than 130.0 percent of the labeled amounts of neomycin and of polymyxin B. It contains not less than 90.0 percent and not more than 110.0 percent of the labeled amount of hydrocortisone. It may contain one or more suitable buffers, dispersants, and preservatives.
Packaging and storage— Preserve in tight, light-resistant containers. The containers or individual cartons are sealed and tamper-proof so that sterility is assured at time of first use.
Sterility 71: meets the requirements.
pH 791: between 3.0 and 7.0.
Assay for neomycin and Assay for polymyxin B— Using an accurately measured volume of Otic Suspension, freshly mixed and free from air bubbles, proceed as directed in the Assay for neomycin and the Assay for polymyxin B under Neomycin and Polymyxin B Sulfates and Hydrocortisone Otic Solution.
Assay for hydrocortisone—
Mobile phase, Standard preparation, and Chromatographic system— Prepare as directed in the Assay for hydrocortisone under Neomycin and Polymyxin B Sulfates, Bacitracin Zinc and Hydrocortisone Ophthalmic Ointment.
Assay preparation— Transfer 3.0 mL of Otic Suspension, freshly mixed and free from air bubbles, to a 200-mL volumetric flask, dilute with a mixture of methanol and water (1:1) to volume, and mix. Filter the solution, rejecting the first 10 mL of the filtrate.
Procedure— Proceed as directed for Procedure in the Assay for hydrocortisone under Neomycin and Polymyxin B Sulfates, Bacitracin Zinc and Hydrocortisone Ophthalmic Ointment. Calculate the quantity, in mg, of C21H30O5 in each mL of the Otic Suspension taken by the formula:
(66.67C)(rU / rS)
in which C is the concentration, in mg per mL, of USP Hydrocortisone RS in the Standard preparation; and rU and rS are the peak responses obtained from the Assay preparation and the Standard preparation, respectively.
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Ahalya Wise, M.S.
Scientist
1-301-816-8161		 (MDANT05) Monograph Development-Antibiotics
Reference Standards Lili Wang, Technical Services Scientist
1-301-816-8129
RSTech@usp.org
71 Radhakrishna S Tirumalai, Ph.D.
Senior Scientist
1-301-816-8339		 (MSA05) Microbiology and Sterility Assurance
USP32–NF27 Page 3064
Chromatographic Column—
Chromatographic columns text is not derived from, and not part of, USP 32 or NF 27.