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Hydrocortisone
(hye'' droe kor' ti sone).
» Hydrocortisone contains not less than 97.0 percent and not more than 102.0 percent of C21H30O5, calculated on the dried basis.
Packaging and storage
Preserve in well-closed containers. Store at 25
Identification
B:
Ultraviolet Absorption
Solution:
10 µg per mL.
Medium:
methanol.
Absorptivities at 242 nm, calculated on the dried basis, do not differ by more than 2.5%.
Loss on drying
Residue on ignition
Chromatographic purity
Mobile phase
Prepare a filtered and degassed mixture of butyl chloride, tetrahydrofuran, methanol, glacial acetic acid, and water (890:56:28:24:0.4), and sonicate to dissolve. Make adjustments if necessary (see System Suitability under Chromatography
Diluting solution
Prepare a solution of butyl chloride, tetrahydrofuran, methanol, and glacial acetic acid (81.5:10:8:0.5).
Standard solution
Prepare a solution in Diluting solution containing 40 µg of USP Hydrocortisone RS per mL. Sonicate for about 5 minutes.
Test solution
Transfer 20 mg of Hydrocortisone to a 10-mL volumetric flask, dissolve in Diluting solution, add Diluting solution to volume to obtain a solution having a known concentration of about 2.0 mg per mL, and sonicate for about 5 minutes.
Chromatographic system (see Chromatography
Procedure
Separately inject equal volumes (about 5 µL) of the Standard solution, the Diluting solution, and the Test solution into the chromatograph, record the chromatograms, and measure the responses for all the peaks, ignoring artifact peaks. Calculate the percentage of impurities in the portion of Hydrocortisone taken by the formula:
1000(C/W)(ri / rS)
in which C is the concentration, in mg per mL, of USP Hydrocortisone RS in the Standard solution; W is the weight, in mg, of Hydrocortisone taken; ri is the response of each individual impurity peak in the Test solution; and rS is the response of the major peak obtained from the Standard solution: not more than 0.5% of any individual impurity and not more than 2.0% of total impurities is found.
Assay
Mobile phase
Prepare a filtered and degassed mixture of water, acetonitrile, and methanol (50:25:25). Make adjustments if necessary (see System Suitability under Chromatography
Diluent
Prepare a mixture of methanol and water (1:1).
Internal standard solution
Prepare a solution of propylparaben in methanol having a concentration of about 1 mg per mL.
Standard stock solution
Dissolve an accurately weighed quantity of USP Hydrocortisone RS in methanol to obtain a solution having a known concentration of about 1 mg per mL.
Standard preparation
Transfer 2.0 mL of Standard stock solution and 2.0 mL of Internal standard solution to a 50-mL volumetric flask, dilute with Diluent to volume, and mix.
Assay preparation
Transfer about 50 mg of Hydrocortisone, accurately weighed, to a 50-mL volumetric flask, dissolve in and dilute with methanol to volume, and mix. Transfer 2.0 mL of this solution and 2.0 mL of Internal standard solution to a 50-mL volumetric flask, dilute with Diluent to volume, and mix.
Chromatographic system (see Chromatography
Procedure
Separately inject equal volumes (about 10 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 C21H30O5 in the portion of Hydrocortisone taken by the formula:
1250C(RU / RS)
in which C is the concentration, in mg per mL, of USP Hydrocortisone RS in the Standard preparation; and RU and RS are the ratios of the peak response of hydrocortisone to that of propylparaben 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 3429
Pharmacopeial Forum: Volume No. 29(5) Page 1506
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