Radiolabeled Dendrimers as Potential PET Agents for Molecular Imaging of Tumor Angiogenesis

Abstract

Introduction: Angiogenesis is a normal physiological process that plays an imperative role during tumor development. We believe that the development of a non-invasive imaging technique targeting angiogenesis can provide a better understanding of this important process. Positron emission tomography (PET) -a highly sensitive imaging technique can offer accurate degree of disease quantification. The phenomenon of enhanced permeability and retention effect (EPR effect) is now becoming the gold standard in cancer targeting drug designing. Dendrimers have the ability to exhibit EPR effect for targeted therapeutic/drug delivery approach. Therefore, molecular imaging of tumor angiogenesis using radio-labeled dendrimers is expected to broaden the possibilities for drug development. Body:In the present chapter, the significance of performing conjugation chemistry of bifunctional chelators quality control parameters of the radiolabeled dendrimer conjugates in vitro stability, animal biodistribution, radiation dosimetry and molecular imaging of animal tumor model after injecting radiotracer have also been discussed in detail. Conclusion:Conjugation of the radio-metal complexes to larger molecules like dendrimers has created a new domain of research in the field of biomedical applications. Therefore, it has been proposed to develop new effective targeting moieties suitable for radiolabeling with PET tracers so as to perform molecular imaging studies.

Controlled-Release Nanosystems with a Dual Function of Targeted Therapy and Radiotherapy in Colorectal Cancer

“…Radiolabeled nanoparticles have been conjugated to target specific molecules and have mainly been employed as agents for diagnosis, as well as studies for biokinetics of new devices based on nanoparticles that comprise radiopharmaceuticals, drug/gene delivery systems, or plasmonic photothermal therapy enhancers. The most common radionuclides for PET imaging are gallium-68 ( 68 Ga), fluorine-18 ( 18 F), carbon-11 ( 11 C), and copper-64 ( 64 Cu), and the most common SPECT imaging radionuclides include technetium-99m ( 99m Tc) and indium-111 ( 111 In) [ 95 , 96 ].…”

“…The general structure of radiolabeled nanoparticles presents the following main components: inner core, targeting biomolecule (BM) (with high affinity for target epitopes), pharmacokinetic-modifying (PKM) linker, bifunctional coupling or chelating agent (BFC), and a radiotracer group, Figure 5 [ 95 , 96 ].…”