Iron Oxide Colloidal Nanoclusters as Theranostic Vehicles and Their Interactions at the Cellular Level

• Published in: Nanomaterials (Basel, Switzerland) Vol. 8; no. 5; p. 315
• Main Authors: Kostopoulou, Athanasia, Brintakis, Konstantinos, Fragogeorgi, Eirini, Anthousi, Amalia, Manna, Liberato, Begin-Colin, Sylvie, Billotey, Claire, Ranella, Anthi, Loudos, George, Athanassakis, Irene, Lappas, Alexandros
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 09.05.2018; MDPI
• Subjects: Animal models; Biocompatibility; Biodistribution; cell interactions; Cell proliferation; Chemical Sciences; Contrast agents; Cytotoxicity; Exploitation; Ferrimagnetism; Health care; Hyperthermia; Immune system; In vivo methods and tests; Inflammation; Iron oxides; Liver; magnetic nanoclusters; Magnetic resonance imaging; Material chemistry; Medical imaging; MRI contrast agents; multicore particle assembly; Nanoclusters; Nanocrystals; Nanomaterials; nanoparticle biodistribution; Nanoparticles; Organic chemistry; Physiology; Polyethylene glycol; scintigraphic imaging; Spleen; Time dependence; Toxicity; MRI contrast agents; cell interactions; magnetic nanoclusters; nanoparticle biodistribution; immune system; multicore particle assembly; scintigraphic imaging
• ISSN: 2079-4991; 2079-4991
• DOI: 10.3390/nano8050315

Advances in surfactant-assisted chemical approaches have led the way for the exploitation of nanoscale inorganic particles in medical diagnosis and treatment. In this field, magnetically-driven multimodal nanotools that perform both detection and therapy, well-designed in size, shape and composition, are highly advantageous. Such a theranostic material-which entails the controlled assembly of smaller (maghemite) nanocrystals in a secondary motif that is highly dispersible in aqueous media-is discussed here. These surface functionalized, pomegranate-like ferrimagnetic nanoclusters (40⁻85 nm) are made of nanocrystal subunits that show a remarkable magnetic resonance imaging contrast efficiency, which is better than that of the superparamagnetic contrast agent Endorem . Going beyond this attribute and with their demonstrated low cytotoxicity in hand, we examine the critical interaction of such nanoprobes with cells at different physiological environments. The time-dependent in vivo scintigraphic imaging of mice experimental models, combined with a biodistribution study, revealed the accumulation of nanoclusters in the spleen and liver. Moreover, the in vitro proliferation of spleen cells and cytokine production witnessed a size-selective regulation of immune system cells, inferring that smaller clusters induce mainly inflammatory activities, while larger ones induce anti-inflammatory actions. The preliminary findings corroborate that the modular chemistry of magnetic iron oxide nanoclusters stimulates unexplored pathways that could be driven to alter their function in favor of healthcare.