BCMaterials Fortnightly Seminar #56: Oihane Arriortua

OIHANE ARRIORTUA

(BCMATERIALS)

Magnetic nanoparticle approaches for magnetic hyperthermia

There is a great success in producing magnetite nanoparticles by chemical methods in the most diverse morphologies, sizes and surface properties. However, the use of these systems for clinical treatments is not as developed. Additionally, the role of the particle size and its functionalization on the performance of certain biomedical applications, in particular hyperthermia, remains obscure from the experimental point of view. Moreover, these systems require having a high biocompatibility difficult to obtain. The fulfillment of these challenges would provide key contributions in a wide application area related with magnetite nanoparticles. In this work different approaches from magnetic nanoparticles point of view for their development in magnetic hyperthermia are presented. The seed mediated protocol applied to the growing of nanoparticles synthesized by thermal decomposition have been proposed and used before to prepare magnetite nanoparticles of a specific size of 18 nm, whose magnetic properties were in agreement with expectations, showing promising values of SAR absorption from AC fields of colloidal nanoparticles. Moreover, different coatings have been proposed for their stabilization in aqueous medium (DMSA, TEOS,TESPMA and PMAO). Furthermore, in order to deliver them to a certain tumoral tissue, a specific bioconjugation with two different peptidic molecules of the RGD type (cyclic and no cyclic) in order to apply these nanoparticles for the destruction of cancerous tissues in vivo assays. To achieve this, we proceeded to a magnetic hyperthermia treatment in rat models with hepatic tumor implants. Thus, in some cases, it was obtained a higher percentage of tumor destruction than originally estimated. This work also reports the preparation of nanocubes and bismuth ferrites in order to get higher SAR values and their applications in bioimaging, respectively.