Physical and chemical limitations to preparation of beta radioactive stents by direct neutron activation

Biomaterials. 2003 Feb;24(3):427-33. doi: 10.1016/s0142-9612(02)00355-1.

Abstract

Pure beta emitters are the sources of choice for intracoronary irradiations in restenosis prevention. In this work we reconsidered preparation of low activity 32P sources by ion-implantation of stable 31P into highly biocompatible pure titanium stents, followed by neutron activation. Gamma-spectrometrical analysis has shown that during activations with high thermal neutrons flux production of gamma-active long-lived contaminants is much beyond the dosimetrically acceptable limit, mainly due to the competing (n,p) reactions induced by the fast neutrons on isotopes of the bulk stent material, and to a lesser extent due to (n,gamma) reactions on chemical impurities. A potential applicability of this method for obtaining alternative beta radioactive stents is discussed.

MeSH terms

  • Brachytherapy / instrumentation*
  • Brachytherapy / methods
  • Chromium Radioisotopes
  • Coronary Disease / prevention & control*
  • Coronary Disease / therapy*
  • Gamma Rays
  • Ions
  • Neutrons*
  • Phosphorus Radioisotopes
  • Spectrophotometry
  • Stents*
  • Titanium

Substances

  • Chromium Radioisotopes
  • Ions
  • Phosphorus Radioisotopes
  • Titanium