Packaging and storage—
Preserve in single-dose containers, preferably of Type I glass, protected from light.
Labeling—
Label containers of Injection intended for intravascular injection to direct the user to discard any unused portion remaining in the container.
Identification—
A:
The IR absorption spectrum of the test specimen, a zinc sulfide cell having a thickness of 0.01 to 0.02 mm being used, exhibits maxima only at the same wavelength as that of a similar preparation of
USP Ioversol RS.
B:
Heat about 1 mL in a crucible: violet vapors are evolved.
Heavy metals, Method I 
231
—
Standard solution—
Into a 50-mL color-comparison tube pipet 2 mL of Standard Lead Solution (20 µg of Pb), and dilute with water to 5 mL.
Test solution—
Into a 50-mL color-comparison tube, pipet a volume of Injection, equivalent to 1 g of ioversol, and dilute with water to 5 mL.
Procedure—
For each of the tubes containing the Standard solution and the Test solution, adjust with 1 N acetic acid or 6 N ammonium hydroxide to a pH between 3.0 and 4.0, using short-range pH indicator paper as external indicator. Add 5.0 mL of ferrous sulfate solution (1 in 1000), dilute with water to 40 mL, and mix. Add 1.2 mL of thioacetamide-glycerin base TS and 2 mL of pH 3.5 Acetate Buffer, allow to stand for 5 minutes, and view downward over a white surface: the color of the solution from the Test solution is not darker than that of the solution from the Standard solution, treated in the same manner. The limit is 20 µg per g.
Other requirements—
It meets the requirements under
Injections 1.
Related compounds—
Test solution—
Dilute an accurately measured volume of Injection with water to obtain a solution containing 1 mg of ioversol per mL.
Procedure—
Separately inject equal volumes (about 50 µL) of the
Standard solution and the
Test solution into the chromatograph, record the chromatograms, and measure the peak responses. Calculate the percentage of each ioversol related compound in the volume of Injection taken by the formula:
100(CS / CU)(rU / rS),
in which
CS is the concentration, in mg per mL, of
USP Ioversol Related Compound A RS or
USP Ioversol Related Compound B RS in the
Standard solution; CU is the concentration, in mg per mL, of Ioversol in the
Assay preparation; rU is the peak response obtained from the
Test solution; and
rS is the average peak response obtained from the
Standard solution. Not more than 0.15% of ioversol related compound A and not more than 1.5% of ioversol related compound B are found.
Assay—
Transfer an accurately measured volume of Injection, equivalent to about 0.5 g of ioversol, to a glass-stoppered, 125-mL conical flask, add 12 mL of 5 N sodium hydroxide, 20 mL of water, and 1 g of powdered zinc, connect the flask to a reflux condenser, and reflux for 30 minutes. Cool the flask to room temperature, rinse the condenser with 20 mL of water, disconnect the flask from the condenser, and filter the mixture. Rinse the flask and filter thoroughly, adding the rinsings to the filtrate. Add 40 mL of 2 N sulfuric acid, and titrate immediately with 0.05 N silver nitrate VS, determining the endpoint potentiometrically, using a silver-silver chloride double junction reference electrode and a silver billet electrode. Each mL of 0.05 N silver nitrate is equivalent to 13.45 mg of C18H24I3N3O9.
