Packaging and storage—
Preserve in tight containers, and store at controlled room temperature.
Expiration date—
The expiration date is not later than two years from the date of manufacture.
Labeling—
Label it to include the following: the amount of 14C, expressed in MBq (or µCi) per Capsule at the time of calibration; the expiration date; the total radioactivity per container; and the statement, “Caution—Radioactive material.”
Radionuclide identification 
821
—
A solution of 1 or more Capsules in 1 N hydrochloric acid when tested using a liquid scintillation counter produces beta emission having a 49 keV mean and a 156 keV max.
Dissolution 711—
Medium:
simulated gastric fluid TS; 500 mL.
Apparatus 1:
50 rpm.
Time:
10 minutes.
Procedure—
Determine the background levels of 14C with a 1-mL portion of the solution under test using a liquid scintillation counter.
Tolerances:
not less than 80% (Q) of the labeled amount of 14C is dissolved in 10 minutes.
Radionuclidic purity 821—
Determine the radionuclidic purity of a solution of 1 or more Capsules in water using a liquid scintillation counter: not less than 99.9% of the radioactivity is present as C 14.
Radiochemical purity—
Adsorbent:
0.25-mm layer of chromatographic cellulose.
Test solution—
Open 2 Capsules and place them in a suitable container, add 8 mL of methanol, and mix.
Reference solution:
40 mg of urea per mL, in water.
Application volume:
20 µL of the Test solution and 4 µL of the Reference solution.
Developing solvent system:
n-butanol saturated with water.
Procedure—
Proceed as directed for
Thin-Layer Chromatography under
Chromatography 621. Locate the spots on the plate by spraying with Ehrlich's reagent. Determine the radioactivity distribution with a suitable radiation detector (see
Radioactivity 821), and obtain the
RF value: the
RF value of the principal spot from the
Test solution corresponds to that obtained from the
Reference solution, and the radioactivity of the
14C band is not less than 90% of the total radioactivity.
Assay for radioactivity 821—
Prepare a solution of 1 or more Capsules in 1 N hydrochloric acid. Using a liquid scintillation counter, determine the radioactivity, in MBq (or mCi) per mL by use of a calibrated system.
Auxiliary Information—
Staff Liaison :
Andrzej Wilk, Ph.D., Senior Scientific Associate
Expert Committee : (RMI05) Radiopharmaceuticals and Medical Imaging Agents 05
USP29–NF24 Page 385
Pharmacopeial Forum : Volume No. 27(2) Page 2126
Phone Number : 1-301-816-8305
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