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.