The permeability of the cell membrane can be increased by electroporation. This is done by delivering short pulses of high voltage near the cell. Nanoparticles are added to the cell surroundings to act as nanoelectrodes. As a result, high voltage pulses are not needed. Nanoparticles locally amplify the electric field and consequently improve the permeability of the cell membrane.
A 2D model of the cell was built and the nanoparticle was added next to it. The cell was kept in a static electric field throughout the simulation. We were interested in what effect the nanoparticle has on increasing the transmembrane voltage and the electric field. We varied a number of parameters of the nanoparticle: material, shape, size and position. The interaction between two nanoparticles at different distances from each other was also tested. To recreate a more realistic situation, a simulation with a larger number of nanoparticles was performed. Finally, a 3D model was built for comparison with the 2D model. The aim was to find the parameters of the nanoparticle that have the largest effect on the observed quantities. The problem was solved using the finite element method.
The best effect on the increase of electric field and transmembrane voltage in 2D simulations was shown by a non-conducting nanoparticle. The larger and more pointed particles caused the larger increase in the observed quantities. For a better effect, the nanoparticle should be located as close as possible to the cell membrane, especially on the parts not facing the electrodes. A larger number of nanoparticles provides a larger increase in transmembrane voltage and electric field. The positive interaction between particles is most noticeable for conductive nanoparticles. Simulations in 3D have shown that the simulation dimension is a parameter that strongly influences the results. While 2D simulations suggested that a non-conducting nanoparticle has a greater influence on the transmembrane voltage, 3D simulations showed the opposite.
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