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Cyanocobalamin Co 57 Capsules

Vitamin B12-57Co.
Vitamin B12-57Co [41559-38-0; 13115-03-2].
» Cyanocobalamin Co 57 Capsules contain Cyanocobalamin in which a portion of the molecules contain radioactive cobalt (57Co) in the molecular structure. Each Capsule contains not less than 90.0 percent and not more than 110.0 percent of the labeled amount of 57Co as cyanocobalamin expressed in megabecquerels (microcuries) at the time indicated in the labeling. The cyanocobalamin content is not less than 90.0 percent and not more than 110.0 percent of the labeled amount.
Specific activity: not less than 0.02 MBq (0.5 µCi) per µg of cyanocobalamin.
Packaging and storage— Preserve in well-closed, light-resistant containers, and store in a cold place.
Labeling— Label the Capsules to include the following: the date of calibration; the amount of cyanocobalamin expressed in µg per Capsule; the amount of 57Co as cyanocobalamin expressed in megabecquerels (microcuries) per Capsule at the time of calibration; the expiration date; and the statement “Caution—Radioactive Material.” The labeling indicates that in making dosage calculations, correction is to be made for radioactive decay, and also indicates that the radioactive half-life of 57Co is 270.9 days.
Radionuclide identification— A solution of 1 or more Capsules in water responds to the test for Radionuclide identification under Cyanocobalamin Co 57 Oral Solution.
Disintegration 701: 30 minutes, testing 1 Capsule in 1 N hydrochloric acid maintained at 37 ± 2 as the immersion fluid.
Uniformity of dosage units: meet the requirements.
Procedure for content uniformity— Determine the instrument response of each of 10 Capsules by measurement in a suitable counting assembly and under identical geometric conditions. Calculate the average radioactivity per Capsule. The radioactivity of none of the Capsules differs by more than 10% from the average. The relative standard deviation is less than 3.5%.
Radiochemical purity— Dissolve the contents of 1 Capsule in 1 mL of water, allow to stand for about 10 minutes, and centrifuge. Use the supernatant as the Test solution. It meets the requirements of the test for Radiochemical purity under Cyanocobalamin Co 57 Oral Solution.
Radionuclidic purity— Dissolve the contents of 1 Capsule in 1 mL of water, allow to stand for about 10 minutes, and centrifuge. Use the supernatant. It meets the requirements of the test for Radionuclidic purity under Cyanocobalamin Co 57 Oral Solution.
Content of cyanocobalamin— Determine the content, in µg per Capsule, of cyanocobalamin as directed under Vitamin B12 Activity Assay 171.
Assay for radioactivity— Using a suitable counting assembly (see Selection of a Counting Assembly under Radioactivity 821), determine the radioactivity, in MBq (µCi) per Capsule, of Cyanocobalamin Co 57 Capsules by use of a calibrated system as directed under Radioactivity 821.
Auxiliary Information— Staff Liaison : Andrzej Wilk, Ph.D., Senior Scientific Associate
Expert Committee : (RMI05) Radiopharmaceuticals and Medical Imaging Agents 05
USP29–NF24 Page 576
Pharmacopeial Forum : Volume No. 29(2) Page 397
Phone Number : 1-301-816-8305