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 40Bacitracin Units per mg.It contains not less than 2.0percent and not more than 10.0percent 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 60days 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 á201BNPñ: meets the requirements.
Sterility á71ñ— Where the label states that it is sterile,it meets the requirements when tested as directed for Membrane Filtrationunder Test for Sterility of the Product to be Examined,except to use Fluid Ato each liter of which has been added 20g of edetate disodium.
pHá791ñ: between 6.0and 7.5,in a (saturated)solution containing approximately 100mg per mL.
Loss on drying á731ñ— Dry about 100mg in a capillary-stoppered bottle in vacuum at 60for 3hours: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 0.001Nhydrochloric acid,if necessary,to obtain solutions of suitable concentrations,adaptable to the linear or working range of the instrument.]
Standard preparations— Transfer 3.11g of zinc oxide,accurately weighed,to a 250-mLvolumetric flask,add 80mLof 1Nhydrochloric acid,warm to dissolve,cool,dilute with water to volume,and mix.This solution contains 10mg of zinc per mL.Further dilute this solution with 0.001Nhydrochloric acid to obtain Standard preparationscontaining 0.5,1.5,and 2.5µg of zinc per mL,respectively.
Test preparation— Transfer about 200mg of Bacitracin Zinc,accurately weighed,to a 100-mLvolumetric flask.Dissolve in 0.01Nhydrochloric acid,dilute with the same solvent to volume,and mix.Pipet 2mLof this solution into a 200-mLvolumetric flask,dilute with 0.001Nhydrochloric acid to volume,and mix.
Procedure— Concomitantly determine the absorbances of the Standard preparationsand the Test preparationat the zinc resonance line of 213.8nm,with a suitable atomic absorption spectrophotometer (see Spectrophotometry and Light-scattering á851ñ),equipped with a zinc hollow-cathode lamp and an air–acetylene flame,using 0.001Nhydrochloric acid as the blank.Plot the absorbances of the Standard preparationsversus 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 Cis the concentration in µg per mL,of zinc in the Test preparation;and Wis the weight,in mg,of the portion of Bacitracin Zinc taken.
Assay— Proceed with Bacitracin Zinc as directed under Antibiotics—Microbial Assays á81ñ.
Auxiliary Information— Staff Liaison:William W.Wright,Ph.D.,Scientific Fellow
Expert Committee:(PA7)Pharmaceutical Analysis 7
USP28–NF23Page 215
Pharmacopeial Forum:Volume No.28(4)Page 1070
Phone Number:1-301-816-8335