Assay
[NOTEUse low-actinic glassware.
]Transfer a volume of Syrup,equivalent to about 10mg of promazine hydrochloride,to a 250-mLseparator.Proceed as directed in the
Assayunder
Promazine Hydrochloride Oral Solution,beginning with Add water to adjust the volume to about 45mL.Calculate the quantity,in mg,of C
17H
20N
2S·HCl in each mLof the Syrup taken by the formula:
(0.25C/V)(AU/AS),
in which
Cis the concentration,in µg per mL,of
USP Promazine Hydrochloride RSin the Standard solution,
Vis the volume,in mL,of Syrup taken,and
AUand
ASare the absorbances of the solution from the Syrup and the Standard solution,respectively.