Assay
Assay preparation
Transfer to a separator an accurately weighed quantity of Injectable Suspension, equivalent to about 50 mg of hydrocortisone, using a total of 25 mL of water to effect the transfer. Extract with four 40-mL portions of chloroform, filtering each portion through chloroform-washed cotton into a 200-mL volumetric flask. Add chloroform to volume, and mix. Pipet 20 mL of this solution into a 100-mL volumetric flask, add chloroform to volume, and mix. Pipet 10 mL of the resulting solution into a glass-stoppered, 100-mL conical flask, evaporate on a steam bath just to dryness, cool, and dissolve the residue in 50.0 mL of alcohol.
Procedure
Proceed as directed for
Procedure under
Assay for Steroids 351. Calculate the quantity, in mg, of C
21H
30O
5 in the portion of Injectable Suspension taken by the formula:
5C(AU / AS).