Packaging and storage
Preserve in tight,light-resistant containers.Store at 25

,excursions permitted between 15

and 30

.
Assay
Transfer about 25mg of Nalorphine Hydrochloride,accurately weighed,to a 250-mLvolumetric flask,dissolve in and dilute with water to volume,and mix.Concomitantly determine the absorbances of this solution and of a Standard solution of
USP Nalorphine Hydrochloride RSin the same medium having a known concentration of about 100µg per mLin 1-cm cells at the wavelength of maximum absorbance at about 285nm,with a suitable spectrophotometer,using water as the blank.Calculate the quantity,in mg,of C
19H
21NO
3·HCl in the Nalorphine Hydrochloride taken by the formula:
0.25C(AU/AS),
in which
Cis the concentration,in µg per mL,of
USP Nalorphine Hydrochloride RSin the Standard solution;and
AUand
ASare the absorbances of the solution of Nalorphine Hydrochloride and the Standard solution,respectively.