synthesis, Characterisation and Radiolabelling of Nanoparticles for applications in Medical imaging
Abstract
Nanoparticles for medical applications are on the verge of having a major impact
in modern medicine. They can be radiolabelled with a range of radionuclides and the
accumulation in the target tissues can be observed by positron emission tomography
(PET) or single photon emission computed tomography (SPECT) imaging, which can
be combined with other imaging modalities such as magnetic resonance imaging
(MRI). The colloidal and structural stability of radiolabelled nanoparticles is crucial to
achieve targeting and an appropriate biodistribution in vivo. This work focuses on the
development of radiolabelling methodologies for nanoparticles to enhance their
stability for SPECT and PET imaging.
The chemical and magnetic properties of superparamagnetic iron oxide
nanoparticles (SPIONs) are attractive for biomedical applications. Combining the use
of SPIONs as MRI contrast agents with PET or SPECT isotopes can overcome some
limitations. Chelator free approaches have been used to synthesise SPIONs that show
good colloidal stability with hydrodynamic sizes of ca. 73 and 58 nm. The SPIONs
were radiolabelled with technetium-99m to give a SPECT/MRI contrast agent. This
method reduces the number of radiochemical synthesis steps required and would
allow rapid adoption into clinical pathways.