Combining magnetic hyperthermia and dual T1/T2 MR imaging using highly versatile iron oxide nanoparticles

[EN] Magnetic hyperthermia and magnetic resonance imaging (MRI) are two of the most important biomedical applications of magnetic nanoparticles (MNPs). However, the design of MNPs with good heating performance for hyperthermia and dual T1/T2 contrast for MRI remains a considerable challenge. In this work, ultrasmall superparamagnetic iron oxide nanoparticles (USPIONs) are synthesized through a simple one-step methodology. A post-synthetic purification strategy has been implemented in order to separate discrete nanoparticles from aggregates and unstable nanoparticles, leading to USPIONs that preserve chemical and colloidal stability for extended periods of time. The optimized nanoparticles exhibit high saturation magnetization and show good heating efficiency in magnetic hyperthermia experiments. Remarkably, the evaluation of the USPIONs as MRI contrast agents revealed that the nanoparticles are also able to provide significant dual T1/T2 signal enhancement. These promising results demonstrate that USPIONs are excellent candidates for the development of theranostic nanodevices with potential application in both hyperthermia and dual T1/T2 MR imaging. We are grateful to the Spanish Government (projects MAT2015-64139-C4-1-R and AGL2015-70235-C2-2-R (MINECO/FEDER)) and the Generalitat Valenciana (Projects PROMETEO/2018/024 and PROMETEOII/2014/047) for financial support. S. S. C. is grateful to the Spanish MEC for his FPU grant. JG acknowledges funding from FCT and the ERDF through NORTE2020 through the project Self-reporting immunestimulating formulation for on-demand cancer therapy with real-time treatment response monitoring (028052). Sánchez-Cabezas, S.; Montes-Robles, R.; Gallo, J.; Sancenón Galarza, F.; Martínez-Máñez, R. (2019). Combining magnetic hyperthermia and dual T1/T2 MR imaging using highly versatile iron oxide nanoparticles. Dalton Transactions. 48(12):3883-3892. https://doi.org/10.1039/c8dt04685a Lee, J.-H., Jang, J., Choi, J., Moon, S. H., Noh, S., Kim, J., … Cheon, J. (2011). Exchange-coupled magnetic nanoparticles for efficient heat induction. Nature Nanotechnology, 6(7), 418-422. doi:10.1038/nnano.2011.95 Hauser, A. K., Wydra, R. J., Stocke, N. A., Anderson, K. W., & Hilt, J. Z. (2015). Magnetic nanoparticles and nanocomposites for remote controlled therapies. Journal of Controlled Release, 219, 76-94. doi:10.1016/j.jconrel.2015.09.039 González, B., Ruiz-Hernández, E., Feito, M. J., López de Laorden, C., Arcos, D., Ramírez-Santillán, C., …