Radioactive isotopes of Indium and their applications

Book Chapter

Summary *

There exist two indium isotopes in nature. In addition, 65 short-lived isotopes and isomeric states of indium can be artificially obtained. However, few of these radionuclides have found important applications. This chapter includes a description of the commonly used production methods, the principal features of these isotopes and their applications. The revision essentially focuses in the most frequently used isotope: 111In. Indeed, 111In plays important roles in medical applications as well as in solid state physics. In medicine, this isotope is widely used since 1970 for labeling radiopharmaceuticals for the imaging or treatment of cancer and other ailments. The wide range of 111In radiopharmaceuticals includes blood cells, antibodies, peptides, analogs of hormones and organic molecules, among others. Moreover, the two successive gamma-rays emitted by 111In are used to study solid state materials using the Perturbed Angular Correlations (PAC) technique. Through the measurement of the hyperfine interactions, it is possible to characterize the atomic environment of 111In. Representative studies include surface characterization, point defects in metals, semiconductors and insulators, identification of phases in specific compounds, gas diffusion in metals and hydrogenation of intermetallic compounds. There are also reported 111In- PAC applications in biological systems, including DNA dynamics, stability of drug carriers and protein structure. In order to give the reader a complete comprehension of the properties and applications of indium isotopes, the scientific concepts underlying these subjects are presented. In this way, certain topics of physics and biology are briefly explained. Among the first ones, the disintegration mechanisms, the common methods to produce radioisotopes and the features of different nuclear reactions are included. Concerning the biomedical concepts, a brief description of the diagnostic and therapeutic radiopharmaceutical is presented. Information provided by the agent in SIGEVA