Tropes

www.azonano.com 2015 00019.txt.txt

#Plasmons Influence Carbon-Based Nanoparticles for Sensitizing Cancerous Tumors In a study published in EPJ D, physicists have shown now that the production of low energy electrons by radio-sensitizers made of carbon nanostructures hinges on a key physical mechanism referred to as plasmons-collective excitations of so-called valence electrons; a phenomenon already documented in rare metal sensitizers. This reseach was conducted by Alexey Verkhovtsev, affiliated with the MBN Research center in Frankfurt, Germany and A f. Ioffe Physical-Technical Institute in St petersburg, Russia and an international team. Nanoparticle radio-sensitizers are nanoscale compounds, typically composed of rare metals such as coated gold, platinum, or gadolinium. Alternatives sensitizers could be made of carbon-based nanostructures, such as fullerenes or nanotubes, provided they are biocompatible and nontoxic. Previous studies have revealed that gold and platinum nanoparticles produce a large number of electrons via the plasmon excitation mechanism. In the case of a carbon nanoparticle this phenomenon yields electrons with higher energy than pure metals, thus inducing greater biological damage. In this study, the authors analysed the spectra of secondary electrons emitted from a carbon nanoparticle composed of fullerite, a crystalline form of C60 fullerene, irradiated by an ion beam consisting of fast protons. They quantified the electron yield in a broad kinetic energy range, using several different theoretical and numerical approaches. They found that a medium with an embedded carbon nanoparticle results in a number of low energy electrons several times higher than that emitted by pure water. This may lead to the development of novel types of sensitizers composed of metallic and carbon-based parts. Source: http://www. springer. co o

< Back - Next >