Corticotropin Zinc Hydroxide Injectable Suspension

Corticotropin zinc hydroxide.
Corticotropin zinc hydroxide [9050-75-3].
» Corticotropin Zinc Hydroxide Injectable Suspension is a sterile suspension of corticotropin adsorbed on zinc hydroxide. Its potency is not less than 80.0 percent and not more than 125.0 percent of the potency stated on the label in USP Corticotropin Units. It contains not less than 1800 µg and not more than 2200 µg of zinc, and not less than 604 µg and not more than 776 µg of anhydrous dibasic sodium phosphate, for each 40 USP Corticotropin Units.
Packaging and storage— Preserve in single-dose or multiple-dose containers, preferably of Type I glass. Store at controlled room temperature.
Labeling— Label it to indicate that it is not recommended for intravenous use and that the suspension is to be well shaken before use. The container label and the package label state the potency in USP Corticotropin Units in each mL.
USP Reference standards 11
USP Ascorbic Acid RS Click to View Structure
USP Corticotropin RS
USP Endotoxin RS
Bacterial endotoxins 85 It contains not more than 3.1 USP Endotoxin Units per USP Corticotropin Unit.
pH 791: between 7.5 and 8.5, determined potentiometrically.
Zinc— Pipet a volume of the well-shaken Injectable Suspension, equivalent to about 6 mg of zinc, into a 125-mL conical flask, and add 2 mL of a buffer mixture containing 5.4 g of ammonium chloride and 26 mL of ammonium hydroxide in each 100 mL. Add 10 mL of water and 2 drops of eriochrome black TS, and titrate with 0.005 M edetate disodium VS to a clear blue endpoint. Perform a blank titration, and make any necessary correction. Each mL of 0.005 M edetate disodium is equivalent to 0.327 mg of Zn.
Anhydrous dibasic sodium phosphate—
Ammonium molybdate reagent— Dissolve 6.4 g of ammonium molybdate in 40 mL of water, and add 50 mL of 10 N sulfuric acid. Mix, and dilute with water to 100 mL. This solution is stable for about 2 weeks.
Stannous chloride reagent— Dissolve 1 g of stannous chloride in 5 mL of hydrochloric acid. Just prior to use, dilute 1 mL of this solution with water to 100 mL.
Standard preparation— Weigh accurately about 275 mg of anhydrous dibasic sodium phosphate (Na2HPO4) into a 1000-mL volumetric flask. Dissolve in and dilute with water to volume. Dilute 10 mL of this solution with water to 100 mL.
Test preparation— Pipet 1 mL of the well-shaken Injectable Suspension into a 25-mL volumetric flask, add 0.1 mL of 10 N sulfuric acid, mix, dilute with water to volume, and again mix.
Procedure— Into separate 100-mL volumetric flasks pipet duplicate 10-mL portions of Test preparation, duplicate 10-mL portions of Standard preparation, and 10 mL of water to provide a blank. Treat each flask as follows. Dilute the contents with water to 60 mL, then add 10 mL of 10 N sulfuric acid, and mix. Add 10 mL of Ammonium molybdate reagent, mix, add 10 mL of water, and again mix. Add slowly, with mixing, 5 mL of Stannous chloride reagent, dilute with water to volume, and mix. Measure the absorbances of the solutions at 10 minutes, accurately timed, after the first addition of the Stannous chloride reagent, at a wavelength of 710 nm, with a suitable spectrophotometer, relative to the blank. Calculate the quantity, in µg, of anhydrous dibasic sodium phosphate in the portion of Injectable Suspension taken by the formula:
25C(AU / AS)
in which C is the concentration, in µg per mL, of Na2HPO4 in the Standard preparation; and AU and AS are the absorbances of the solutions from the Test preparation and the Standard preparation, respectively.
Other requirements— It meets the requirements under Injections 1.
Assay— Add sufficient 0.1 N hydrochloric acid to Injectable Suspension to effect complete solution, and using this in making the Assay preparation, proceed as directed in the Assay under Corticotropin Injection.
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Monograph Thomas A. Sigambris, M.S.
Scientific Liaison
(BIO12010) Monographs - Biologics and Biotechnology 1
Reference Standards RS Technical Services
85 Radhakrishna S Tirumalai, Ph.D.
Principal Scientific Liaison
(GCM2010) General Chapters - Microbiology
USP35–NF30 Page 2773