Procedure
Separately inject three equal volumes (about 100 µL) of the
Assay preparation and the
Standard preparation into the chromatograph, record the chromatograms, and measure the responses for the major peaks. Calculate the potency, in USP Oxytocin Units per mL, in the portion of Nasal Solution taken by the formula:
C(rU / rS),
in which
C is the concentration, in USP Oxytocin Units per mL, of USP Oxytocin RS in the
Standard preparation; and
rU and
rS are the mean peak responses obtained for oxytocin from the
Assay preparation and the
Standard preparation, respectively.