Uniformity of dosage units 
905
:
meet the requirements for
Weight Variation with respect to tetracycline hydrochloride and to novobiocin sodium and for
Content Uniformity with respect to prednisolone.
Procedure for content uniformity for prednisolone—
Mobile phase
,
Internal standard solution, and
Chromatographic system—Prepare as directed in the
Assay under
Prednisolone.
Test preparation—
Transfer 1 Tablet to a suitable container, add 7 mL of diluted methanol (2 in 7) for each 1.5 mg of prednisolone in the Tablet, based on the labeled amount, and allow to stand for 90 minutes, occasionally agitating gently to ensure that the Tablet disintegrates. For each 1.5 mg of prednisolone, add 3.0 mL of
Internal standard solution, 12 mL of water-saturated chloroform, and about 10 glass beads. Securely close the container, and shake by mechanical means for 30 minutes. Carefully open the container, add 0.5 mL of sodium carbonate solution (1 in 4), reclose the container, and shake by mechanical means for 5 minutes. Centrifuge, remove the upper layer by aspiration, discarding the aspirated liquid, and retain the clear chloroform layer (
Test preparation).
Procedure—
Proceed as directed for
Procedure in the
Assay under
Prednisolone. Calculate the quantity, in mg, of prednisolone (C
21H
28O
5) in the Tablet taken by the formula:
0.015C(RU / RS),
in which the terms are as defined therein.
Limit of 4-epianhydrotetracycline 226—
To an accurately weighed quantity of finely powdered Tablets, equivalent to about 250 mg of tetracycline hydrochloride, add 10 mL of 0.1 N hydrochloric acid, and adjust with 6 N ammonium hydroxide to a pH of 7.8. Transfer this solution with the aid of
EDTA Buffer to a 50-mL volumetric flask, dilute with
EDTA Buffer to volume, and mix. Use this solution, without delay, as the
Test Solution: not more than 2.0% is found.
Assay for prednisolone—
Mobile phase
,
Internal standard solution, and
Chromatographic system—Prepare as directed in the
Assay under
Prednisolone.
Standard preparation—
Transfer about 10 mg of
USP Prednisolone RS, accurately weighed, to a 100-mL volumetric flask, add 20.0 mL of
Internal standard solution, and swirl to dissolve. Dilute with water-saturated chloroform to volume, and mix. Transfer 15.0 mL of this solution to a suitable container, add 7 mL of diluted methanol (2 in 7), securely close the container, and shake by mechanical means for 30 minutes. Carefully open the container, add 0.5 mL of sodium carbonate solution (1 in 4), reclose the container, and shake by mechanical means for 5 minutes. Centrifuge, remove the upper layer by aspiration, discarding the aspirated liquid, and retain the clear chloroform layer (
Standard preparation).
Assay preparation—
Weigh and finely powder not less than 20 Tablets. Transfer an accurately weighed portion of the powder, equivalent to about 1.5 mg of prednisolone, to a suitable container containing about 10 glass beads. Add 3.0 mL of Internal standard solution, 12 mL of water-saturated chloroform, and 7 mL of diluted methanol (2 in 7), securely close the container, and shake by mechanical means for 30 minutes. Carefully open the container, add 0.5 mL of sodium carbonate solution (1 in 4), reclose the container, and shake by mechanical means for 5 minutes. Centrifuge, remove the upper layer by aspiration, discarding the aspirated liquid, and retain the clear chloroform layer (Assay preparation).
Procedure—
Proceed as directed for
Procedure in the
Assay under
Prednisolone. Calculate the quantity, in mg, of prednisolone (C
21H
28O
5) in the portion of Tablets taken by the formula:
0.015C(RU / RS),
in which the terms are as defined therein.
