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Bacitracin Zinc

Bacitracins, zinc complex.
Bacitracins zinc complex [1405-89-6].
» Bacitracin Zinc is the zinc salt of a kind of bacitracin or a mixture of two or more such salts. It has a potency of not less than 40 Bacitracin Units per mg. It contains not less than 2.0 percent and not more than 10.0 percent of zinc (Zn), calculated on the dried basis.
Packaging and storage— Preserve in tight containers, and store in a cool place.
Labeling— Label it to indicate that it is to be used in the manufacture of nonparenteral drugs only. Where it is packaged for prescription compounding, label it to indicate that it is not sterile and that the potency cannot be assured for longer than 60 days after opening, and to state the number of Bacitracin Units per milligram. Where it is intended for use in preparing sterile dosage forms, the label states that it is sterile or must be subjected to further processing during the preparation of sterile dosage forms.
Thin-layer chromatographic identification test 201BNP: meets the requirements.
Sterility 71— Where the label states that it is sterile, it meets the requirements when tested as directed for Membrane Filtration under Test for Sterility of the Product to be Examined, except to use Fluid A to each L of which has been added 20 g of edetate disodium.
pH 791: between 6.0 and 7.5, in a (saturated) solution containing approximately 100 mg per mL.
Loss on drying 731— Dry about 100 mg in a capillary-stoppered bottle in vacuum at 60 for 3 hours: it loses not more than 5.0% of its weight.
Zinc content— [NOTE—The Standard preparations and the Test preparation may be quantitatively diluted with 0.001 N hydrochloric acid, if necessary, to obtain solutions of suitable concentrations, adaptable to the linear or working range of the instrument.]
Standard preparations— Transfer 3.11 g of zinc oxide, accurately weighed, to a 250-mL volumetric flask, add 80 mL of 1 N hydrochloric acid, warm to dissolve, cool, dilute with water to volume, and mix. This solution contains 10 mg of zinc per mL. Further dilute this solution with 0.001 N hydrochloric acid to obtain Standard preparations containing 0.5, 1.5, and 2.5 µg of zinc per mL, respectively.
Test preparation— Transfer about 200 mg of Bacitracin Zinc, accurately weighed, to a 100-mL volumetric flask. Dissolve in 0.01 N hydrochloric acid, dilute with the same solvent to volume, and mix. Pipet 2 mL of this solution into a 200-mL volumetric flask, dilute with 0.001 N hydrochloric acid to volume, and mix.
Procedure— Concomitantly determine the absorbances of the Standard preparations and the Test preparation at the zinc resonance line of 213.8 nm, with a suitable atomic absorption spectrophotometer (see Spectrophotometry and Light-scattering 851), equipped with a zinc hollow-cathode lamp and an air–acetylene flame, using 0.001 N hydrochloric acid as the blank. Plot the absorbances of the Standard preparations versus concentration, in µg per mL, of zinc, and draw the straight line best fitting the three plotted points. From the graph so obtained, determine the concentration, in µg per mL, of zinc in the Test preparation. Calculate the content of zinc, in percent, in the portion of Bacitracin Zinc taken by the formula:
1000C / W,
in which C is the concentration in µg per mL, of zinc in the Test preparation; and W is the weight, in mg, of the portion of Bacitracin Zinc taken.
Residual solvents 467: meets the requirements.
(Official January 1, 2007)
Assay— Proceed with Bacitracin Zinc as directed under Antibiotics—Microbial Assays 81.
Auxiliary Information— Staff Liaison : Brian D. Gilbert, Ph.D., Scientist
Expert Committee : (MDANT05) Monograph Development-Antibiotics
USP29–NF24 Page 235
Pharmacopeial Forum : Volume No. 28(4) Page 1070
Phone Number : 1-301-816-8223