Radiolabelled nanoparticles for nanotoxicology studies

(Nanowerk News) The rapidly accelerating use of nanoparticles in consumer products is causing considerable concern because of known and documented health problems associated with exposure of humans to some particulate materials and because nanoparticles have been proven to be able to penetrate biological barriers and cellular structures in a way that larger particles cannot. Thus, various initiatives are now being taken to address the question of safety of nanoparticles, and the study of the toxic potential of nanoparticles has given rise to the field of "nanotoxicology".
Nanoparticles are extremely difficult to detect and quantify once distributed in a material or biological system. A way to overcome this problem, at least for laboratory studies, is to label them so that they can unambiguously be traced in subsequent studies.
One method of labelling is based on fluorescence; another one, which offers many benefits in terms of easy detection methods and high sensitivity, is to label the nanoparticles with an appropriate radioisotope. This may be achieved by irradiating them with a proton or deuteron beam produced by a cyclotron (a type of particle accelerator). This procedure requires specialised knowledge and equipment, controlled laboratory space, and careful safety considerations.
This paper ("Radiolabelling of engineered nanoparticles for in vitro and in vivo tracing applications using cyclotron accelerators "), compiled by a team of scientists working in the European Commission Joint Research Centre, Institute for Health and Consumer Protection (JRC-IHCP), together with collaborators from external research organisations, describes and discusses a variety of cyclotron-based methods that can be used to radiolabel nanoparticles, and presents selected results obtained by the authors in their laboratories on a number of different nanoparticles types, suitable for a range of different in vitro and in vivo tracing studies of relevance to the field of nanotoxicology.
Details are presented of a direct ion-beam activation technique, developed by the cyclotron team of the JRC-IHCP with its MC40 Cyclotron, and capable of activating industrially manufactured nanoparticles, as well as methods based on radiochemical synthesis, spark ignition technology, and a cyclotron-driven neutron activator. The spark ignition technique was developed by collaborating scientists at the Helmholtz Zentrum Muenchen (Comprehensive Pneumology Center, Institute of Lung Biology and Disease), and the neutron activator was designed by Advanced Accelerator Applications-AAA (France) together with the Centro Ricerche Casaccia, ENEA (Italy), and constructed and tested at JRC-IHCP.
Source: European Commission Joint Research Centre, Institute for Health and Consumer Protection (JRC-IHCP)