Assay
Mobile phase,Internal standard solution,Standard preparation,and Chromatographic system
Prepare as directed in theAssay underHydrocortisone Valerate.
Assay preparation
Transfer an accurately weighed quantity of Ointment,equivalent to about 1mg of hydrocortisone valerate,to a screw-capped tube.Add 8.0mLof a mixture of methanol and water (3:1),and swirl to disperse.Heat in a steam bath until melted (about 30seconds),swirl again,and allow to cool at room temperature.Add 2.0mLofInternal standard solution,and mix.Centrifuge for 5minutes,and filter the supernatant,if necessary,to obtain a clear solution.
Procedure
Proceed as directed in the
Assay under
Hydrocortisone Valerate.Calculate the quantity,in mg,of hydrocortisone valerate (C
26H
38O
6)in the portion of Ointment taken by the formula:
0.01C(RU/RS),
in which the terms are as defined therein.