Procedure
Separately inject equal volumes (about 20µL)of the
Standard preparationand the
Assay preparationinto the chromatograph,record the chromatograms,and measure the responses for the major peaks.Calculate the quantity,in mg,of C
9H
13NO
2·HCl in each mLof Ophthalmic Solution taken by the formula:
100(C/V)(rU/rS),
in which
Cis the concentration,in mg per mL,of
USP Phenylephrine Hydrochloride RSin the
Standard preparation,Vis the volume,in mL,of Ophthalmic Solution taken,and
rUand
rSare the peak responses obtained from the
Assay preparationand the
Standard preparation,respectively.