Iron Oxide Nanoradiomaterials: Combining Nanoscale Properties with Radioisotopes for Enhanced Molecular Imaging

Abstract

The combination of the size-dependent properties of nanomaterials with radioisotopes is emerging as a novel tool for molecular imaging. There are numerous examples already showing how the controlled synthesis of nanoparticles and the incorporation of a radioisotope in the nanostructure offer new features beyond the simple addition of different components. Among the different nanomaterials, iron oxide-based nanoparticles are the most used in imaging because of their versatility. In this review, we will study the different radioisotopes for biomedical imaging, how to incorporate them within the nanoparticles, and what applications they can be used for. Our focus is directed towards what is new in this field, what the nanoparticles can offer to the field of nuclear imaging, and the radioisotopes hybridized with nanomaterials for use in molecular imaging.

68Ga-Sienna+ for PET-MRI Guided Sentinel Lymph Node Biopsy: Synthesis and Preclinical Evaluation in a Metastatic Breast Cancer Model

“…Sienna+ is a clinically approved SPIO and CE-marked device used in several clinical trials in conjunction with a magnetometer for intrasurgical SLN guidance 32. 68 Ga was chosen due to its availability from a GMP-grade generator, its short half-life ideal for SLN imaging, and the possibility of using a chelate-free approach that allows for simple GMP compatible radiolabelling 33-35. Sienna+ nanoparticles were labelled with 68 Ga without a chelator in a fast and efficient way.…”

Iron oxide nanoparticles as multimodal imaging tools

“…a tumor in case of 18 F-FDG that consumes more glucose than a healthy tissue. 53 Using IONP, it was possible to bring several improvement to the standard PET/SPECT imaging method by: (i) binding different radio-tracers to IONP [18F]uorodeoxyglucose (FDG), copper-61/64, gallium-66/68, zirconium-89, and iodine-124 for PET, 54 and 99mTc, 125I, 111I, 125I and 131I for SPECT, [54][55][56] that increase radio-tracer lifetime and targeting efficacy, 55 (ii) enabling simultaneous anatomical and functional imaging by combining PET/SPEC with MRI, taking advantage of the MRI contrasting ability of IONP, (iii) enlarging the SPECT/ PET imaging capacity to a therapeutic activity through the use of a theranostic IONP probe that can trigger drugs delivery, immunotherapy, hyperthermia, or photodynamic therapy. 19,57 In addition, PET/SPECT lead to high detection sensitivity, e.g.…”

Molecular Imaging with 68Ga Radio-Nanomaterials: Shedding Light on Nanoparticles

“…Non-radioactive precursors and the radioisotope are combined to yield intrinsically radiolabeled nanoparticles. Optimal nanoparticle synthetic conditions and careful isotope selection ensure radioisotope incorporation within the core of the nanoparticle [32]. This …”

“…Even though passive accumulation of NPs in the tumor site has proven to be a valuable method for imaging angiogenesis, active targeting of cancerous cells by means of tumor targeting moieties substantially increases probe specificity providing better quality images. Kim et al [96] conjugated PEG-coated 68 Ga-NOTA-IONPs with oleanolic acid (OA), a novel tumor targeting molecule, to specifically target HT-29 cancer cells in a murine model [32]. Functional amines in PEG coating enabled tumor targeting moiety (oleanolic acid) and chelating agent for 68 Ga (NOTA) incorporation.…”