Standard preparation— Prepare as directed in the test for Limit of nandroloneunder Nandrolone Decanoate Injection.

Test preparation— Transfer an accurately measured volume of Injection,equivalent to about 50mg of nandrolone phenpropionate,to a 10-mLvolumetric flask,dilute with acetone to volume,and mix.

Procedure— Proceed as directed for Procedurein the test for Limit of nandroloneunder Nandrolone Decanoate Injection.

Isoniazid reagent— Dissolve 500mg of isoniazid in about 250mLof methanol,add 0.63mLof hydrochloric acid,dilute with methanol to 500.0mL,and mix.

Standard preparation— Transfer about 25mg of USP Nandrolone Phenpropionate RS,accurately weighed,to a 100-mLvolumetric flask,dissolve in chloroform,dilute with chloroform to volume,and mix.Transfer 5.0mLof this solution to a 50-mLvolumetric flask,dilute with chloroform to volume,and mix.

Assay preparation— Transfer an accurately measured volume of Injection,equivalent to about 50mg of nandrolone phenpropionate,to a 200-mLvolumetric flask,dilute with chloroform to volume,and mix.Transfer 5.0mLof this solution to a 50-mLvolumetric flask,dilute with chloroform to volume,and mix.

Procedure— Transfer 5.0mLeach of the Standard preparation,of the Assay preparation,and of chloroform to provide the blank,to separate 10-mLvolumetric flasks,dilute each flask with Isoniazid reagentto volume,and mix.Allow the flasks to stand for 1hour with occasional shaking.Concomitantly determine the absorbances of the solutions in 1-cm cells at the wavelength of maximum absorbance at about 380nm,with a suitable spectrophotometer,against the blank.Calculate the quantity,in mg,of C27H34O3in each mLof the Injection taken by the formula: in which Cis the concentration,in µg per mL,of USP Nandrolone Phenpropionate RSin the Standard preparation,Vis the volume,in mL,of Injection taken,and AUand ASare the absorbances of the solutions from the Assay preparationand the Standard preparation,respectively.