Highly efficient t2 cobalt ferrite nanoparticles vectorized for internalization in cancer cells

Uniform cobalt ferrite nanoparticles have been synthesized using an electrochemical synthesis method in aqueous media. Their colloidal, magnetic, and relaxometric properties have been analyzed. The novelty of this synthesis relies on the use of iron and cobalt foils as precursors, which assures the reproducibility of the iron and cobalt ratio in the structure. A stable and biocompatible targeting conjugate nanoparticle-folic acid (NP-FA) was developed that was capable of targeting FA receptor positivity in HeLa (human cervical cancer) cancer cells. The biocompatibility of NP-FA was assessed in vitro in HeLa cells using the MTT assay, and morphological analysis of the cytoskeleton was performed. A high level of NP-FA binding to HeLa cells was confirmed through qualitative in vitro targeting studies. A value of 479 Fe+Co mM􀀀1s􀀀1 of transverse relaxivity (r2) was obtained in colloidal suspension. In addition, in vitro analysis in HeLa cells also showed an important effect in negative T2 contrast. Therefore, the results show that NP-FA can be a potential biomaterial for use in bio medical trials, especially as a contrast agent in magnetic resonance imaging (MRI).
We are grateful for the financial support provided by the Spanish Ministry of Economy and Competitiveness who funded this research under project PGC2018-095642-B-I00 and to the Fondo Social Europeo-Gobierno de Aragón, Ministerio de la Economía y Competitividad del Gobierno de España for the public funding of Proyectos I+D+I—Programa Estatal de Investigación, Desarrollo e Innovación Orientada a los Retos de la Sociedad (project n. BIO2017-84246-C2-1-R).