163bl Studies of Ferrite Based Magnetic Nanoparticle Transport Mechanisms and Magnetocytolysis Effects on a Model Cell Cultures

Hector Luis Roddriguez, Adriana Herrera, Carlos Rinaldi, and Madeline Torres. Chemical Engineering, University of Puerto Rico Mayguez Campus, Mayaguez, PR 00680

Suspended magnetic nanoparticles, such as ferrites, are known to dissipate energy under an oscillating magnetic field. Such energy dissipation could be employed to locally raise the temperature inside a tumor to 41-46°C, promoting cell death. This technique is promising in the development of a novel cancer treatment with potentially fewer side effects, compared to radio and chemotherapy. Cytotoxicity experiments, transport analysis, and magnetocytolysis experiments were performed in Caco-2 cells (human colon adenocarcinoma epithelial cells) using dextran coated ferrite nanoparticles. Cytotoxicity was examined by exposing the cells to various concentrations of nanoparticles for 2, 24, 48 hours. Cell viability was analyzed using a fluorimetric assay which measures cell metabolism. These studies indicate that viability of the cells was not affected by the nanoparticles in the concentration range 0.08-0.2 mg/mL. Nanoparticle suspensions with a concentration of 0.144 mg/mL were applied to the cells and the system was exposed to a magnetic field of 3.1 kA/m, and a frequency of 1 kHz. It was found for a period of 45 and 60 minutes that the viability of cells decrease to 40% of the negative control. Additionally, with the purpose of investigating the exact transport mechanism of the ferrite nanoparticles, these were coated with cross-linked fluorescein isothiocyanate dextran (FITC Dextran). Cells were exposed to the fluorescent labeled nanoparticles and then examined using a confocal laser scanning microscope. Preliminary results suggest that nanoparticles were transported through the cell membrane, invading the cytoplasm of the cells. This fluorescent label will allow further investigation of the nanoparticle transport mechanism through the cells.