Radiolabeled nanomaterial for cancer diagnostics and therapeutics: principles and concepts

Abstract

In the last three decades, radiopharmaceuticals have proven their effectiveness for cancer diagnosis and therapy. In parallel, the advances in nanotechnology have fueled a plethora of applications in biology and medicine. A convergence of these disciplines has emerged more recently with the advent of nanotechnology-aided radiopharmaceuticals. Capitalizing on the unique physical and functional properties of nanoparticles, radiolabeled nanomaterials or nano-radiopharmaceuticals have the potential to enhance imaging and therapy of human diseases. This article provides an overview of various radionuclides used in diagnostic, therapeutic, and theranostic applications, radionuclide production through different techniques, conventional radionuclide delivery systems, and advancements in the delivery systems for nanomaterials. The review also provides insights into fundamental concepts necessary to improve currently available radionuclide agents and formulate new nano-radiopharmaceuticals.

Keywords: Cancer; Nano-radiopharmaceuticals; Nanotechnology; Radiolabeled nanomaterial; Radionuclides.

Fig. 1

Schematic representation of the underlying nuclear decay that results in production of α, ß-, ß + , Auger electron, and γ radioactive emissions. EC = electron capture, IC = internal conversion

Fig. 2

Schematic representation of SPECT (left) and PET (right) imaging

Fig. 3

Schematic representation of a cyclotron

Fig. 4

Schematic representation of a fission reaction

Fig. 5

Schematic representation of neutron activation

Fig. 6

Schematic representation of a generator

Fig. 7

Schematic representation of the bystander (left panel), self-dose (middle panel), and crossfire effect (right panel) effects of radionuclide therapy

Fig. 8

Schematic representation of various methods of direct radiolabeling nanomaterial, i.e., physical interaction, chemical adsorption, neutron/proton beam activation, coprecipitation, radioisotope exchange, and radiohalogenation

Fig. 9

Schematic representation of some methods of indirect radiolabeling of nanomaterials, i.e., entrapment and use of bifunctional chelators