Assay
Alcohol-isooctane and Isooctane-alcohol
Shake equal volumes of 90 percent alcohol and isooctane in a separator for 10 to 15 minutes, and allow to separate. Withdraw the layers into separate containers, designating the lower layer as alcohol-isooctane and the upper layer as isooctane-alcohol.
Assay preparation
Transfer an accurately measured volume of Injection, equivalent to about 5 mg of desoxycorticosterone acetate, to a separator containing 50 mL of Isooctane-alcohol. Extract with six 20-mL portions of Alcohol-isooctane, receiving the extracts in a 250-mL volumetric flask, dilute with Alcohol-isooctane to volume, and mix. Pipet 10 mL of this solution into a glass-stoppered, 50-mL conical flask, evaporate on a steam bath with the aid of a gentle current of air just to dryness, and dissolve the residue in 20.0 mL of alcohol.
Procedure
Proceed as directed for
Procedure under
Assay for Steroids
351
. Calculate the quantity, in mg, of C
23H
32O
4 in each mL of the Injection taken by the formula:
0.5(C / V)(AU / AS),
in which
V is the volume, in mL, of Injection taken.