Packaging and storage—
Preserve in single-dose or in multiple-dose containers, preferably of Type I glass.
Labeling—
Label it to indicate that the Injection is not to be used if it is darker than slightly yellow, or is discolored in any other way.
Identification—
It responds to the
Thin-Layer Chromatographic Identification Test 
201
, 5 µL of the clear supernatant being used to prepare the
Assay preparation in the
Assay and 5 µL of the stock solution being used to prepare the
Standard preparation in the
Assay being applied to the plate, and a solvent system consisting of a mixture of ethyl acetate, methanol, and ammonium hydroxide (22:2:1) being used to develop the chromatogram.
Other requirements—
It meets the requirements under
Injections 1.
Assay—
Assay preparation—
Transfer an accurately measured volume of Injection, equivalent to about 500 mg of procainamide hydrochloride, to a 500-mL volumetric flask, dilute with methanol to volume, and mix. Transfer 5.0 mL of this stock solution to a 100-mL volumetric flask, reserving the remainder of the stock solution for the
Identification test. Dilute with
Mobile phase to volume, and mix.
Procedure—
Proceed as directed for
Procedure in the
Assay under
Procainamide Hydrochloride. Calculate the quantity, in mg, of C
13H
21N
3O·HCl in each mL of the Injection taken by the formula:
10,000(C / V)(rU / rS),
in which
C is the concentration, in mg per mL, of
USP Procainamide Hydrochloride RS in the
Standard preparation, V is the volume, in mL, of Injection taken, and
rU and
rS are the peak responses obtained from the
Assay preparation and the
Standard preparation, respectively.
