Specific activity:
not less than 0.02MBq (0.5µCi)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 CautionRadioactive 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 270.9days.
Disintegration á701ñ:
30minutes,testing 1Capsule in 1Nhydrochloric 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 10Capsules 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 1Capsule in 1mLof water,allow to stand for about 10minutes,and centrifuge.Use the supernatant as the
Test solution.It meets the requirements of the test for
Radiochemical purity under
Cyanocobalamin Co 57Oral Solution.
Radionuclidic purity
Dissolve the contents of 1Capsule in 1mLof water,allow to stand for about 10minutes,and centrifuge.Use the supernatant.It meets the requirements of the test for
Radionuclidic purity under
Cyanocobalamin Co 57Oral Solution.
Assay for radioactivity
Using a suitable counting assembly (see
Selection of a Counting Assemblyunder
Radioactivity á821ñ),determine the radioactivity,in MBq (µCi)per Capsule,of Cyanocobalamin Co 57Capsules by use of a calibrated system as directed under
Radioactivity á821ñ.