Bacitracin and Polymyxin B Sulfate Topical Aerosol
» Bacitracin and Polymyxin B Sulfate Topical Aerosol is a suspension of Bacitracin and Polymyxin B Sulfate in a suitable vehicle, packaged in a pressurized container with a suitable inert propellant. It contains not less than 90.0 percent and not more than 130.0 percent of the labeled amounts of bacitracin and polymyxin B. It may contain a suitable local anesthetic.
Packaging and storage—
Preserve in pressurized containers, and avoid exposure to excessive heat.
USP Reference standards 
11
—
11—
USP Bacitracin Zinc RS
USP Polymyxin B Sulfate RS
[Note—Prepare the specimen for the following tests and assays as follows. Maintain the container in the inverted position throughout this procedure. Store the container in a freezer at 
70
for 16 to 24 hours. Remove the container from the freezer, promptly puncture the container, and allow the propellant to volatilize. Open the container, and mix the contents. ]
70 for 16 to 24 hours. Remove the container from the freezer, promptly puncture the container, and allow the propellant to volatilize. Open the container, and mix the contents. ]
Thin-layer chromatographic identification test 201BNP—
A portion of the contents of 1 container prepared as directed above and tested as directed for Creams, Lotions, and Ointments meets the requirements.
201BNP—
A portion of the contents of 1 container prepared as directed above and tested as directed for Creams, Lotions, and Ointments meets the requirements.
Water, Method I 921:
not more than 0.5%, an accurately weighed portion of the contents of 1 container, prepared as directed above, being used, and 20 mL of a mixture of toluene and methanol (7:3) being used in place of methanol in the titration vessel.
921:
not more than 0.5%, an accurately weighed portion of the contents of 1 container, prepared as directed above, being used, and 20 mL of a mixture of toluene and methanol (7:3) being used in place of methanol in the titration vessel.
Other requirements—
It meets the requirements for Pressure Test, Minimum Fill, and Leakage Test under Aerosols, Nasal Sprays, Metered-Dose Inhalers, and Dry Powder Inhalers 601.
601.
Assay for bacitracin—
Proceed as directed for bacitracin under Antibiotics—Microbial Assays 81, using an accurately weighed portion of the contents of 1 container, prepared as directed above, equivalent to about 500 USP Bacitracin Units. Transfer to a suitable separator containing about 50 mL of ether, and extract with three 25-mL portions of Buffer No. 1. Combine the buffer extracts in a 100-mL volumetric flask, dilute with Buffer No. 1 to volume, and mix. Add sufficient 0.01 N hydrochloric acid to an accurately measured volume of this solution so that the amount of hydrochloric acid in the Test Dilution will be the same as in the median dose level of the Standard, and quantitatively dilute with Buffer No. 1 to obtain a Test Dilution having a bacitracin concentration assumed to be equal to the median dose level of the Standard.
81, using an accurately weighed portion of the contents of 1 container, prepared as directed above, equivalent to about 500 USP Bacitracin Units. Transfer to a suitable separator containing about 50 mL of ether, and extract with three 25-mL portions of Buffer No. 1. Combine the buffer extracts in a 100-mL volumetric flask, dilute with Buffer No. 1 to volume, and mix. Add sufficient 0.01 N hydrochloric acid to an accurately measured volume of this solution so that the amount of hydrochloric acid in the Test Dilution will be the same as in the median dose level of the Standard, and quantitatively dilute with Buffer No. 1 to obtain a Test Dilution having a bacitracin concentration assumed to be equal to the median dose level of the Standard.
Assay for polymyxin B—
Proceed as directed for polymyxin B under Antibiotics—Microbial Assays 81 Transfer an accurately weighed portion of the contents of 1 container, prepared as directed above, equivalent to about 5000 USP Polymyxin B Units, to a suitable separator containing about 50 mL of ether, and extract with three 25-mL portions of Buffer No. 6. Combine the buffer extracts in a 100-mL volumetric flask, dilute with Buffer No. 6 to volume, and mix. Dilute an accurately measured volume of this solution, quantitatively and stepwise, with Buffer No. 6 to obtain a Test Dilution having a concentration of polymyxin B assumed to be equal to the median dose level of the Standard.
81 Transfer an accurately weighed portion of the contents of 1 container, prepared as directed above, equivalent to about 5000 USP Polymyxin B Units, to a suitable separator containing about 50 mL of ether, and extract with three 25-mL portions of Buffer No. 6. Combine the buffer extracts in a 100-mL volumetric flask, dilute with Buffer No. 6 to volume, and mix. Dilute an accurately measured volume of this solution, quantitatively and stepwise, with Buffer No. 6 to obtain a Test Dilution having a concentration of polymyxin B assumed to be equal to the median dose level of the Standard.
Auxiliary Information—
Please check for your question in the FAQs before contacting USP.
| Topic/Question | Contact | Expert Committee |
|---|---|---|
| Monograph | Ahalya Wise, M.S.
Senior Scientific Liaison 1-301-816-8161 |
(SM12010) Monographs - Small Molecules 1 |
| Reference Standards | RS Technical Services 1-301-816-8129 rstech@usp.org |
USP35–NF30 Page 2296
Pharmacopeial Forum: Volume No. 28(4) Page 1070