Identification—
A:
The retention time of the major peak in the chromatogram of the Assay preparation corresponds to that in the chromatogram of the Standard preparation, as obtained in the Assay.
Assay—
Standard preparation—
Prepare a solution of
USP Mangafodipir Trisodium RS in water having a known concentration of about 2 mg per mL. Transfer 10.0 mL of this solution to a 50-mL volumetric flask, add 5.0 mL of
Phosphate buffer, dilute with water to volume, and mix.
[NOTE—Store under nitrogen to avoid excessive exposure to air and light.
]
Assay preparation—
Transfer an accurately measured volume of Injection, equivalent to about 100 mg of mangafodipir trisodium, to a 50-mL volumetric flask, dilute with water to volume, and mix. Transfer 10.0 mL of this solution to a 50-mL volumetric flask, add 5.0 mL of Phosphate buffer, dilute with water to volume, and mix. [NOTE—Store under nitrogen to avoid excessive exposure to air and light.]
Chromatographic system—
Prepare as directed in the
Assay under
Mangafodipir Trisodium. Chromatograph the
Standard preparation, and record the peak responses as directed for
Procedure: the column efficiency is not less than 1000 theoretical plates; and the tailing factor is not more than 2.3.
Procedure—
Separately inject equal volumes (about 10 µL) of the
Standard preparation and the
Assay preparation into the chromatograph, record the chromatograms, and measure the responses for the major peaks. Calculate the quantity, in mg, of mangafodipir trisodium (C
22H
27MnN
4Na
3O
14P
2) in each mL of the Injection taken by the formula:
250(C/V)(rU / rS),
in which
C is the concentration, in mg per mL, of
USP Mangafodipir Trisodium RS in the
Standard preparation; V is the volume, in mL, of Injection taken to prepare the
Assay preparation; and
rU and
rS are the mangafodipir peak responses obtained from the
Assay preparation and the
Standard preparation, respectively.
191
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