meso-2,3-Dimercaptosuccinic acid,99mTc complex.

Packaging and storage— Preserve in single-dose containers,at a temperature between 15and 30.Do not freeze or store above 30.Protect from light.

Labeling— Label it to include the following,in addition to the information specified for Labelingunder Injections á1ñ:the time and date of calibration;the amount of 99mTc as labeled succimer expressed as total megabecquerels (microcuries or millicuries)and concentration as megabecquerels (microcuries or millicuries)per mLat the time of calibration;the expiration date and time;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 99mTc is 6.0hours.In addition,the labeling states that it is not to be used if discoloration or particulate matter is observed.[NOTE—Abeyond-use time of 30minutes shall be stated on the label upon constitution with Sodium Pertechnetate Tc 99m Injection.]

USP Reference standards á11ñ— USP Endotoxin RS.

Bacterial endotoxins á85ñ— The limit of endotoxin content is not more than 175/VUSP Endotoxin Unit per mLof the Injection,when compared with the USP Endotoxin RS,in which Vis the maximum recommended total dose,in mL,at the expiration date or time.

pHá791ñ: between 2.0and 3.0.

Radiochemical purity— Activate a 65-×95-mm silicic acid thin-layer chromatographic plate by heating at 100-110for 30minutes.Cool over silica gel and immediately apply 1µLof Injection,appropriately diluted,if necessary,to a radioactive concentration of 18.5to 370MBq (0.5to 10mCi)per mL,about 17mm from one end of the chromatographic plate,and allow to dry.Develop the chromatogram over a period of about 30to 45minutes by ascending chromatography,using n-butanol saturated with 0.3Nhydrochloric acid,and air-dry.Determine the radioactive distribution by scanning the chromatogram with a suitable collimated radiation detector.Not less than 85%of the total radioactivity is found as succimer at an RFbetween 0.45and 0.70.Hydrolyzed 99mTc is located at the origin (RF0to 0.15)and the unbound 99mTc is located at the solvent front (RF1.0).

Biological distribution— Inject intravenously between 3.7MBq and 92.5MBq (100µCi and 2500µCi)of Injection,in a volume of 0.2to 0.25mL,into the caudal vein of each of three 125-g to 225-g anesthetized Sprague-Dawley female rats.Clamp the opening of the urethra with a hemostat.Sacrifice the animals 1hour after the injection,and carefully remove the kidneys,bladder,and liver and spleen of each as threeseparate organs by dissections.Place each organ and the remaining carcass (excluding the tail)in separate,suitable counting containers,and determine the radioactivity,in counts per minute,in each container with an appropriate detector,using the same counting geometry.Determine the percentage of administered radioactive dose in each organ:not less than 40%of the administered radioactive dose is found in the kidneys and a ratio of not less than 6:1of the administered dose is found in the ratio kidneys/(liver and spleen),in not fewer than two of the animals.

Other requirements— It meets the requirements of the tests for Radionuclide identificationand Radionuclidic purityunder Sodium Pertechnetate Tc 99m Injection.It meets also the requirements under Injections á1ñ,except that it may be distributed or dispensed prior to completion of the test for Sterility,the latter test being started on the day of final manufacture,and except that it is not subject to the recommendation on Volume in Container.

Assay for radioactivity á821ñ— Using a suitable counting assembly (see Selection of a Counting Assembly),determine the radioactivity,in MBq (µCi)per mL,of Injection by use of a calibrated system.

Expert Committee:(RMI)Radiopharmaceuticals and Medical Imaging Agents

USP28–NF23Page 1864

Phone Number:1-301-816-8305