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 90.0percent and not more than 130.0percent of the labeled amounts of neomycin and polymyxin B.It contains not less than 90.0percent and not more than 110.0percent 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 á71ñ: meets the requirements.
pHá791ñ: between 2.0and 4.5.
Assay for neomycin— Proceed as directed under Antibiotics—Microbial Assays á81ñ,using an accurately measured volume of Otic Solution diluted quantitatively and stepwise with Buffer No.3to yield a Test Dilutionhaving a concentration assumed to be equal to the median dose level of the Standard (1.0µg of neomycin per mL).
Assay for polymyxin B— Proceed as directed under Antibiotics—Microbial Assays á81ñ,using an accurately measured volume of Otic Solution diluted quantitatively and stepwise with Buffer No.6to yield a Test Dilutionhaving a concentration assumed to be equal to the median dose level of the Standard (10Polymyxin 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 hydrocortisoneunder Neomycin and Polymyxin B Sulfates,Bacitracin Zinc and Hydrocortisone Ophthalmic Ointment.
Assay preparation— Transfer 3.0mLof Otic Solution to a 200-mLvolumetric flask,dilute with a mixture of methanol and water (1:1)to volume,and mix.
Procedure— Proceed as directed for Procedurein the Assay for hydrocortisoneunder Neomycin and Polymyxin B Sulfates,Bacitracin Zinc and Hydrocortisone Ophthalmic Ointment.Calculate the quantity,in mg,of C21H30O5in each mLof the Otic Solution taken by the formula:
(66.67C)(rU/rS),
in which Cis the concentration,in mg per mL,of USP Hydrocortisone RSin the Standard preparation,and rUand rSare the peak responses obtained from the Assay preparationand the Standard preparation,respectively.
Auxiliary Information— Staff Liaison:William W.Wright,Ph.D.,Scientific Fellow
Expert Committee:(PA7)Pharmaceutical Analysis 7
USP28–NF23Page 1358
Phone Number:1-301-816-8335