Sodium Phosphate P 32 Solution

Phosphoric-32P acid, disodium salt.
Dibasic sodium phosphate-32P [7635-46-3].
» Sodium Phosphate P 32 Solution is a solution suitable for either oral or intravenous administration, containing radioactive phosphorus (32P) processed in the form of Dibasic Sodium Phosphate from the neutron bombardment of elemental sulfur. Nonradioactive Dibasic Sodium Phosphate may be added during the processing.
Sodium Phosphate P 32 Solution contains not less than 90.0 percent and not more than 110.0 percent of the labeled amount of 32P as phosphate expressed in megabecquerels (microcuries or millicuries) per mL at the time indicated in the labeling. Other chemical forms of radioactivity are absent.
Packaging and storage— Preserve in single-dose or multiple-dose containers that previously have been treated to prevent adsorption.
Labeling— Label it to include the following: the time and date of calibration; the amount of 32P as phosphate expressed in total megabecquerels (microcuries or millicuries) and in megabecquerels (microcuries or in millicuries) per mL at the time of calibration; the name and quantity of any added preservative or stabilizer; a statement of the intended use, whether oral or intravenous; a statement of whether the contents are intended for diagnostic or therapeutic use; the expiration date; and the statements “Caution—Radioactive Material,” and “Not for intracavitary use.” 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 32P is 14.3 days.
Radionuclide identification—
A: The beta radiation of the Solution, measured according to the procedure set forth under Radioactivity 821, shows a mass absorption coefficient within ±5% of the value found for a specimen of a known standard of the same radionuclide when determined under identical counting conditions and geometry.
B: Its beta-ray and/or bremsstrahlung spectrum is identical to that of a specimen of 32P of known purity showing no distinct photopeaks and no energies greater than 1.710 MeV.
Bacterial endotoxins 85 It contains not more than 175/V USP Endotoxin Unit per mL of the Injection, when compared with the USP Endotoxin RS, in which V is the maximum recommended total dose, in mL, at the expiration date or time.
pH 791: between 5.0 and 6.0.
Radiochemical purity— Place a measured volume, appropriately diluted with phosphoric acid solution (1 in 20) such that it provides a count rate of about 20,000 counts per minute, about 45 mm from the end of a 25- × 300-mm strip of chromatographic paper (see Chromatography 621), and allow to dry. Develop the chromatogram by descending chromatography, using a mixture of tertiary butyl alcohol, water, and formic acid (40:20:5). Allow to dry, and determine the position of the phosphoric acid by spraying the paper with a solution prepared by dissolving 5 g of ammonium molybdate in 100 mL of water and pouring, with constant stirring, into a mixture of 12 mL of nitric acid and 24 mL of water. Determine the position of the radioactivity distribution by scanning with a collimated radiation detector. The radioactivity appears in one band only, corresponding in RF value to the phosphoric acid.
Other requirements— Solution intended for intravenous use meets the requirements under Injections 1, except that the Solution 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— Using a suitable counting assembly (see Assay, Beta-emitting under Radioactivity 821), determine the radioactivity, in MBq (mCi) per mL, of Solution by use of a calibrated system as directed under Radioactivity 821).
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Ian DeVeau, Ph.D.
Director, Veterinary Drugs and Radiopharmaceuticals
(RMI05) Radiopharmaceuticals and Medical Imaging Agents 05
Reference Standards Lili Wang, Technical Services Scientist
85 Radhakrishna S Tirumalai, Ph.D.
Senior Scientist
(MSA05) Microbiology and Sterility Assurance
USP32–NF27 Page 3299