Identification—
Powder a number of Tablets, equivalent to about 25 mg of cortisone acetate, add 25 mL of solvent hexane, and extract for 15 minutes with occasional agitation. Decant and discard the supernatant, then extract the residue with 5 mL of chloroform, with frequent agitation, for 5 minutes. Filter, add 10 mL of methanol to the filtrate, mix, evaporate the solvent on a steam bath with the aid of a current of air, then dry the residue at 105
for 30 minutes: the residue so obtained responds to
Identification test
A under
Cortisone Acetate.
Dissolution 
711
—
Medium:
0.5% of sodium lauryl sulfate solution; 1000 mL.
Apparatus 2:
50 rpm.
Time:
45 minutes.
Standard solution—
Dissolve a suitable quantity of
USP Cortisone Acetate RS, accurately weighed, in the
Dissolution Medium to obtain a solution having a known concentration of about 5.55 µg of cortisone acetate per mL.
Procedure—
Determine the amount of C23H30O6 in solution on filtered portions of the Dissolution Medium, suitably diluted, in 1-cm cells, at the wavelength of maximum absorbance at about 242 nm in comparison with the Standard solution.
Tolerances—
Not less than 75% (Q) of the labeled amount of C23H30O6 is dissolved in 45 minutes.
Uniformity of dosage units 905:
meet the requirements.
PROCEDURE FOR CONTENT UNIFORMITY—
Mobile phase
,
Internal standard solution,
Standard preparation,
Resolution solution, and
Chromatographic system—Proceed as directed in the
Assay.
Test solution—
Place 1 Tablet in a stoppered, 50-mL conical flask, deposit 0.25 mL of water on the tablet, insert the stopper in the flask, and allow to stand for 30 minutes. Add 2.5 mL of isopropyl alcohol, and place the unstoppered flask on a steam bath. Boil gently, if necessary, until the tablet disintegrates, then evaporate the solvent with the aid of a current of air. Remove from the steam bath, add 10.0 mL of Internal standard solution for each 5 mg of cortisone acetate declared, insert the stopper, and sonicate vigorously for 10 minutes. Proceed as directed for the Assay preparation, beginning with “Filter a portion”, to obtain the Test solution.
Procedure—
Proceed as directed in the
Assay but to chromatograph the
Test solution instead of the
Assay preparation. Calculate the quantity, in mg, of cortisone acetate (C
23H
30O
6) in each Tablet taken by the formula:
W(V / 25)(RU / RS),
in which
W is the weight, in mg, of
USP Cortisone Acetate RS taken for the
Standard preparation; V is the volume, in mL, of
Internal standard solution added to the
Test solution; and the other terms are as defined therein.
Assay—
Mobile phase—
Prepare a filtered and degassed mixture of
n-butyl chloride, water-saturated
n-butyl chloride, tetrahydrofuran, methanol, and glacial acetic acid (95:95:14:7:6). Make adjustments if necessary (see
System Suitability under
Chromatography 621).
Internal standard solution—
Prepare a solution of methylparaben in Mobile phase having a concentration of about 0.04 mg per mL.
Standard preparation—
Transfer about 12 mg of
USP Cortisone Acetate RS, accurately weighed, to a glass-stoppered, 50-mL conical flask, add 25.0 mL of
Internal standard solution, and sonicate for 5 minutes. Combine approximately 1 mL of this solution with 3 mL of
Mobile phase to obtain the
Standard preparation.
Resolution solution—
Dissolve a quantity of hydrocortisone acetate in the Standard preparation to obtain a solution containing about 0.1 mg of hydrocortisone acetate per mL.
Assay preparation—
Accurately weigh, then finely powder, not fewer than 20 Tablets. Transfer an accurately weighed portion of the powder, equivalent to about 12 mg of cortisone acetate, to a stoppered conical flask. Add 25.0 mL of Internal standard solution, insert the stopper in the flask, and sonicate vigorously for 5 minutes. Pass a portion through a polytef syringe filter, then combine approximately 1 mL of the filtrate and 3 mL of Mobile phase to obtain the Assay preparation.
Chromatographic system
(see
Chromatography 621)—The liquid chromatograph is equipped with a 254-nm detector and a 4.6-mm × 25-cm column that contains packing L3. The flow rate is about 1 mL per minute. Chromatograph the
Resolution solution, and record the peak responses as directed for
Procedure: the resolution,
R, between cortisone acetate and hydrocortisone acetate is not less than 2.2 (if necessary, add equal parts of
n-butyl chloride and water-saturated
n-butyl chloride to the
Mobile phase to meet this requirement). Chromatograph the
Standard preparation, and record the peak responses as directed for
Procedure: the relative retention times are 0.7 for methylparaben and 1.0 for cortisone acetate; and the relative standard deviation for replicate injections is not more than 2.0%.
Procedure—
Separately inject equal volumes (about 15 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 cortisone acetate (C
23H
30O
6) in the portion of Tablets taken by the formula:
W(RU / RS),
in which
W is the weight, in mg, of
USP Cortisone Acetate RS taken for the
Standard preparation; and
RU and
RS are the peak response ratios of cortisone acetate to the internal standard obtained from the
Assay preparation and the
Standard preparation, respectively.
