Radiolabelled nanoparticles for cancer diagnosis

Recently, nanomedicine emerged as one of the most promising branches in biomedical field with the development of new tools for diagnostic and therapeutic purposes such as functionalized nanoparticles for the detection and prevention of cancer. Here, we systematically reviewed different types of radiolabelled nanoparticles for tumor imaging focusing on nuclear medicine applications.A systematic analysis of literature was performed using the following string: "[ALL (label* AND diagnosis AND tumor AND nanoparticle* AND radio*) AND PUBYEAR > 2006]" on PubMed and Scopus, limiting the analysis to English articles and original papers from 2007 to 2018. Seventy-one original papers were included in the analysis, second divided between radiolabelled NPs for SPECT (n = 34) and PET imaging (n = 37).Among 34 original articles that analysed radiolabelled NPs for tumor SPECT imaging, 12 were radiolabelled with indium-111, 6 with iodine (3 with iodine-125; 3 with iodine-131), 14 with Technetium-99m, 1 with lutetium-177, and 1 with rhenium-188. Among 37 original papers regarding radiolabelled NPs for tumor PET imaging, 16 were radiolabelled with copper-64, 5 with fluorine-18, 5 with gallium (4 with gallium-68, 1 with gallium-66), 4 with iodine-124, 1 with titanium 45, 6 with zirconium-89.Several NPs can be engineered to achieve suitable chemistry, physical properties, and morphology, overcoming many limitations of other conventional approaches. By modifying their size, it is possible to increase or decrease their biological half-life and maximize uptake in tumors due to the enhanced permeability and retention effect. It is also possible to bind to their surface different ligands like monoclonal antibodies or peptides to increase their specificity for tumor antigens.