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Innovative Magnetic Nanoparticles for PET/MRI Bimodal Imaging.

ABSTRACT: Superparamagnetic iron oxide nanoparticles were developed as positron emission tomography (PET) and magnetic resonance imaging (MRI) bimodal imaging agents. These nanoparticles (NPs), with a specific nanoflower morphology, were first synthesized and simultaneously functionalized with 3,4-dihydroxy-l-phenylalanine (LDOPA) under continuous hydrothermal conditions. The resulting NPs exhibited a low hydrodynamic size of 90 ± 2 nm. The functional groups of LDOPA (-NH₂ and -COOH) were successfully used for the grafting of molecules of interest in a second step. The nanostructures were modified by poly(ethylene glycol) (PEG) and a new macrocyclic chelator MANOTA for further ⁶⁴Cu radiolabeling for PET imaging. The functionalized NPs showed promising bimodal (PET and MRI) imaging capability with high r ₂ and r ₂* (T ₂ and T ₂* relaxivities) values and good stability. They were mainly uptaken from liver and kidneys. No cytotoxicity effect was observed. These NPs appear as a good candidate for bimodal tracers in PET/MRI.

SUBMITTER: Thomas G

PROVIDER: S-EPMC6648431 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Innovative Magnetic Nanoparticles for PET/MRI Bimodal Imaging.

Thomas Guillaume G Boudon Julien J Maurizi Lionel L Moreau Mathieu M Walker Paul P Severin Isabelle I Oudot Alexandra A Goze Christine C Poty Sophie S Vrigneaud Jean-Marc JM Demoisson Fréderic F Denat Franck F Brunotte François F Millot Nadine N

ACS omega 20190205 2

Superparamagnetic iron oxide nanoparticles were developed as positron emission tomography (PET) and magnetic resonance imaging (MRI) bimodal imaging agents. These nanoparticles (NPs), with a specific nanoflower morphology, were first synthesized and simultaneously functionalized with 3,4-dihydroxy-l-phenylalanine (LDOPA) under continuous hydrothermal conditions. The resulting NPs exhibited a low hydrodynamic size of 90 ± 2 nm. The functional groups of LDOPA (-NH<sub>2</sub> and -COOH) were succe ...[more]

PMID: 31459499

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Dataset Information

Innovative Magnetic Nanoparticles for PET/MRI Bimodal Imaging.

Publications

Innovative Magnetic Nanoparticles for PET/MRI Bimodal Imaging.

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