Packaging and storage—
Preserve in single-dose or in multiple-dose containers,preferably of Type Ior Type IIglass.
Labeling—
Where necessary,label it to indicate that it is to be diluted before use.
Identification—
The retention time of the major peak in the chromatogram of the
Assay preparationcorresponds to that of the
Standard preparationobtained as directed in the
Assay.
pHá791ñ:
between 3.0and 6.5,determined potentiometrically in a solution prepared by adding 5mLof water and 1drop of saturated potassium chloride solution to 5mLof the Injection.
Assay—
Assay preparation—
Transfer an accurately measured volume of Injection,equivalent to about 7.5mg of nitroglycerin,to a 100-mLvolumetric flask,dissolve in and dilute with Mobile phaseto volume,and mix.
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
3H
5N
3O
9in the portion of Injection taken by the formula:
100C(rU/rS),
in which
Cis the concentration,in mg per mL,of nitroglycerin in the
Standard preparation,and
rUand
rSare the peak responses of nitroglycerin obtained from the
Assay preparationand the
Standard preparation,respectively.