Technetium (99mTc) medronic acid explained

Technetium (^99mTc) medronic acid is a pharmaceutical product used in nuclear medicine to localize bone metastases^[1] as well as other diseases that can alter the natural turn-over in the bone by bone scintigraphy.^[2]

Chemistry

The drug is a complex of medronic acid (MDP, methylene diphosphonate), the simplest bisphosphonate, with technetium-99m (^99mTc), a radionuclide that emits gamma rays. The exact structure of the complex is not known.^[3]

Manufacture

^99mTc-MDP must be prepared in a radiopharmacy. It is usually supplied as a "cold kit" to which radioactive ^99mTc from a generator is added. Kit composition may vary between suppliers, but contents typically includes medronic acid, stannous chloride dihydrate and sometimes ascorbic acid.^[4] Pertechnetate, eluted from the generator is added to the kit vial, which is swirled and left to stand. The labelling efficiency, an indication of how much ^99mTc remains in pertechnetate form rather than bound to the MDP, can be measured using chromatography.^{[5] [6] [7] [8]}

External links

• Web site: Technetium Tc 99m medronate . U.S. National Library of Medicine . Drug Information Portal .

Notes and References

1. Uematsu T, Yuen S, Yukisawa S, Aramaki T, Morimoto N, Endo M, Furukawa H, Uchida Y, Watanabe J . 6 . Comparison of FDG PET and SPECT for detection of bone metastases in breast cancer . AJR. American Journal of Roentgenology . 184 . 4 . 1266–73 . April 2005 . 15788608 . 10.2214/ajr.184.4.01841266 .
2. http://dailymed.nlm.nih.gov/dailymed/getFile.cfm?id=8073&type=pdf&name=19b726a5-c744-46ab-b33d-7e86bbd84b5e FDA Label: MDP Multidose Utilipack
3. http://www.genome.jp/dbget-bin/www_bget?dr+D02029 KEGG Drug: D02029
4. Web site: List of labelling kits for the preparation of a technetium-99m labelled bone scanning agent. Human Health Campus. IAEA. 3 March 2017.
5. Web site: MDP Bracco. Bracco Diagnostics. 3 March 2017.
6. Web site: Kit for the Preparation of Technetium Tc 99m Medronate for Injection. Pharmalucence. 3 March 2017.
7. Web site: TechneScan MDP Kit for the Preparation of Technetium Tc 99m Medronate Package Insert. Mallinckrodt Medical. 3 March 2017.
8. Mather SJ, Ellison D . Reduction-mediated technetium-99m labeling of monoclonal antibodies . Journal of Nuclear Medicine . 31 . 5 . 692–7 . May 1990 . 2341907 .