Yttrium radioisotope

Yttrium is a light, silver-colored metal which is stable in air up to 400 C and inflammable at 500°C, producing YjOj. Yttrium also reacts with O2 in water to release H2, preferably at pH > 6. The stable (natural) yttrium isotope is Y, and there are 19 unstable isotopes and 18 isomers. The yttrium radioisotope with the longest half-life (106.6 days) is Y. Y appears... 

The curves in Figure 10 were drawn from a composite of many observations made in the course of metabolic studies including radioisotopes of yttrium and the 14 lanthanide elements administered as chlorides. These experiments were performed at the Crocker Laboratory, University of California, in the years 1943 to 1957 under the general direction of J. G. Hamilton, K. G. Scott, and P. W. Durbin. Some of the information was presented in Laboratory Progress Reports, but much is unpublished. 

Dobson, E. L., Gofman, J. W., Jones, H. B., Kelly, L. S. and Walker, L. A. (1949). Studies with colloids containing radioisotopes of yttrium, zirconium, columbium and lanthanum. II. The controlled selective localization of radioisotopes of yttrium, zirconium and columbium in the bone marrow, liver, and spleen, J. Lab. Clin. Med. 34, 305. 

Several clinical trials have evaluated (or continue to evaluate) monoclonal antibodies to which a radioactive tag has been conjugated. These are usually employed as potential anti-cancer agents. The rationale is selective delivery of the radioactivity directly to the tumour site. Most of the radioisotopes being evaluated are /i-emitters these include I and I (iodine), Re and Re (rhenium) and (yttrium). The medium-energy radioactivity these emit is capable of penetrating... 

Radioisotopes are also used in radiation therapy to treat cancer. The goal in radiation therapy is to kill malignant cells, while protecting healthy tissue from radiation effects. Radioisotopes such as yttrium-90, a beta emitter, may be placed directly in the tumor. Alternatively, the diseased tissue may be subjected to beams of gamma radiation. Cobalt-60 used in radiation therapy is prepared by a series of transmutations ... 

Ibritumomab is a murine IgGi anti-CD20 antibody, the parent of the engineered chimeric antibody rituximab, a monoclonal antibody with mouse variable and human constant regions. It induces apoptosis and has antiproliferative effects. Ibritumomab tiuxetan (Zevalin) is composed of the monoclonal antibody ibritumomab, the linking chelator tiuxetan, and the radioisotope yttrium (1). 

Radioimmunotherapy. The recent approval of the anti-CD20 radioimmunoconjugates I-tositumomab (Bexxar) and °Y-ibritumomab tiuxetan (Zevalin) has provided clinicians with a novel treatment option for patients with indolent NHLs. Both I-tositumomab and °Y-ibritumomab tiuxetan are mouse antibodies linked to a radioisotope, either iodine 131 I) or yttrium 90 Y). 

A radioisotope battery is one of the choice for energy source of meteorological obseiwation and development of undersea and space[l]. We have considered a strontium-90 (half-life 28.8y) heat-source model of a radioisotope battery and improved it in two aspects—radiation dose reduction and improvement of thermal conductivity—adding graded structure to the model[2]. The present study reports the dose reduction of bremsstrahlung photons from -ray of - "Sr and its daughter nuclide yttrium-90. The calculation was carried out by a continuous energy Monte Carlo code, MCNP 4A[3]. 

Strontium radioisotopes in milk can be determined by making use of an ion exchange procedure. The milk sample is allowed to stand for 2 weeks to achieve a sufficient accumulation. Citrate and both yttrium and strontium carriers are added. The solution is applied onto a column of cation then anion exchangers. Strontium and yttrium are retained on the cation and anion exchangers, respectively. Yttrium is washed out from the anion exchanger with hydrochloric acid and precipitated as yttrium oxalate. After weighing the precipitate and determining the chemical yield the activity of the °Y is measured. In the presence of the yttrium oxalate is dissolved in concentrated nitric acid, and yttrium is extracted with tributyl phosphate. Lanthanum-140 remains in the aqueous phase. Yttrium is back-washed with nitric acid and precipitated as its oxalate. In an unfavorable case, i.e., when the amount of exceeds by several orders that of °Sr, the above separation procedure has to be repeated. 

J.K. Christie, J. Malik, A. Tilocca, Bioactive glasses as potential radioisotope vectors for in situ cancer therapy investigating the structural effects of yttrium. Phys. Chem. Chem. Phys. 13(39), 17749-17755 (2011)... 

J.K. Christie, A. Tilocca, Integrating biological activity into radioisotope vectors molecular dynamics models of yttrium-doped bioactive glasses. J. Mater. Chem. 22(24), 12023-12031... 

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