Authors: H.L. Rodríguez, C. Barrera, A. Herrera, V. Ayala, M. Latorre, C. Rinaldi, M. Torres-Lugo
Affilation: University of Puerto Rico, Puerto Rico
Pages: 321 - 324
Keywords: magnetic nanoparticles, magnetic fluid hyperthermia, nanoparticle uptake
To date, two main avenues by which nanoparticles appear to induce cell death have been proposed, magnetocytolysis and magnetic fluid hyperthermia (MFH). Little is known regarding the mechanisms of cell death and the main factors involved. This work focused on the examination of cell death mechanisms when an AC magnetic field is continuously applied for 120 min or applied in two intervals of 60 min. Magnetite nanoparticles were decorated with carboxymethyl-dextran (Mag-CMDX) and Poly (ethylene glycol) (Mag-PEG) polymers. Uptake results indicated that Mag-CMDX was internalized by Caco-2 cell in 24 hours, reaching saturation. Mag-PEG nanoparticles demonstrated a higher uptake by MCF-7 cells for a period of 1 week. Results demonstrated a significant decrease in cell viability for a magnetic field exposure of 120 min and a resting time of 24 hours when compared to similar field applications but with shorter resting times. The net effect in cell viability of applying the magnetic field continuously for 120 min or at two different intervals of 60 min was the same. The process of cell death appears to be mainly apoptotic and it was found that the percentage of cells showing apoptotic features increased at higher exposure times.