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Hydrocortisone Butyrate
(hye'' droe kor' ti sone bue' ti rate).
C25H36O6
Pregn-4-ene-3,20-dione, 11,21-dihydroxy-17-(1-oxobutoxy)-,(11 Cortisol 17-butyrate. 11 » Hydrocortisone Butyrate contains not less than 97.0 percent and not more than 102.0 percent of C25H36O6, calculated on the dried basis.
Packaging and storage
Preserve in well-closed containers.
Clarity of solution
Identification
Solution:
10 µg per mL.
Medium:
methanol.
Absorptivities at 242 nm, calculated on the dried basis, do not differ by more than 3.0%.
Loss on drying
Chromatographic purity
Solution A
Prepare a filtered and degassed solution of 1 g of monobasic potassium phosphate in 1000 mL of water, adjust with 45% potassium hydroxide to a pH of 5.5, and mix. Make adjustments if necessary (see System Suitability under Chromatography
Solution B
Use filtered and degassed acetonitrile.
Mobile phase
Use variable mixtures of Solution A and Solution B as directed for Chromatographic system.
Solvent
Prepare a mixture of acetonitrile and Solution A (80:20).
Standard solution
Dissolve an accurately weighed quantity of USP Hydrocortisone Butyrate RS in Solvent to obtain a solution having a known concentration of about 0.5 mg per mL.
Test solution
Transfer about 50 mg of Hydrocortisone Butyrate, accurately weighed, to a 50-mL volumetric flask, dissolve in and dilute with Solvent to volume, and mix.
Chromatographic system
(see Chromatography
Procedure
Separately inject equal volumes (about 5 µL) of the Test solution and theStandard solution into the chromatograph, record the chromatograms, and measure the areas for the major peaks, disregarding any peak having a percentage of 0.05% or less. Calculate the percentage of each impurity in the portion of Hydrocortisone Butyrate taken by the formula:
100(CS / CU)(ri / rS)
in which CS is the concentration, in mg per mL, of USP Hydrocortisone Butyrate RS in the Standard solution; CU is the concentration, in mg per mL, of Hydrocortisone Butyrate in the Test solution; ri is the peak area for each impurity obtained from the Test solution; and rS is the peak area for hydrocortisone butyrate obtained from the Standard solution: not more than 1.0% of any individual impurity is found; and not more than 2.0% of total impurities is found.
Assay
Mobile phase
Prepare a filtered and degassed mixture of water, acetonitrile, and glacial acetic acid (124:76:1). Make adjustments if necessary (see System Suitability under Chromatography
Solvent
Prepare a mixture of tetrahydrofuran and glacial acetic acid (1000:1).
Diluting solution
Prepare a filtered solution of methanol, water, and glacial acetic acid (500:500:1).
Standard preparation
Dissolve an accurately weighed quantity of USP Hydrocortisone Butyrate RS in Solvent, and dilute quantitatively, and stepwise if necessary, with Solvent to obtain a solution having a known concentration of about 0.1 mg per mL. Transfer 10.0 mL of this solution to a 50-mL volumetric flask, dilute with Diluting solution to volume, and mix.
System suitability solution
Dissolve suitable quantities of propyl 4-hydroxybenzoate and USP Hydrocortisone Butyrate RS in Solvent, and dilute quantitatively, and stepwise if necessary, with Solvent to obtain a solution having known concentrations of about 0.1 mg of each per mL. Transfer 10 mL of this solution to a 50-mL volumetric flask, dilute with Diluting solution to volume, and mix.
Assay preparation
Transfer about 50 mg of Hydrocortisone Butyrate, accurately weighed, to a 50-mL volumetric flask, dissolve in and dilute with Solvent to volume, and mix. Transfer 5.0 mL of this solution to a 50-mL volumetric flask, dilute with Solvent to volume, and mix. Transfer 10.0 mL of this solution to a 50-mL volumetric flask, dilute with Diluting solution to volume, and mix.
Chromatographic system
(see Chromatography
Procedure
Separately inject equal volumes (about 5 µL) of the Standard preparation and the Assay preparation into the chromatograph, record the chromatograms, and measure the responses for the major peaks. Calculate the quantity, in mg, of C25H36O6 in the portion of Hydrocortisone Butyrate taken by the formula:
2500C(rU / rS)
in which C is the concentration, in mg per mL, of USP Hydrocortisone Butyrate RS in the Standard preparation; and rU and rS are the peak responses obtained from the Assay preparation and the Standard preparation, respectively.
Auxiliary Information
Please check for your question in the FAQs before contacting USP.
USP35NF30 Page 3437
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