Neomycin and Polymyxin B Sulfates and Hydrocortisone Otic Solution
» Neomycin and Polymyxin B Sulfates and Hydrocortisone Otic Solution is a sterile solution containing the equivalent of not less than 90.0 percent and not more than 130.0 percent of the labeled amounts of neomycin and 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 solvents.
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 2.0 and 4.5.
Assay for neomycin— Proceed as directed under Antibiotics—Microbial Assays 81, using an accurately measured volume of Otic Solution diluted quantitatively and stepwise with Buffer No. 3 to yield a Test Dilution having a concentration assumed to be equal to the median dose level of the Standard (1.0 µg of neomycin per mL).
Assay for polymyxin B— Proceed as directed under Antibiotics—Microbial Assays 81, using an accurately measured volume of Otic Solution diluted quantitatively and stepwise with Buffer No. 6 to yield a Test Dilution having a concentration assumed to be equal to the median dose level of the Standard (10 Polymyxin B Units per mL). Add to each test dilution of the Standard a quantity of Neomycin Standard, dissolved in Buffer No. 6, to obtain the same concentration of neomycin present in the Test Dilution.
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 Solution to a 200-mL volumetric flask, dilute with a mixture of methanol and water (1:1) to volume, and mix.
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 Solution 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 3063
Chromatographic Column—
Chromatographic columns text is not derived from, and not part of, USP 32 or NF 27.