Electrophoresis-assisted accumulation of conductive nanoparticles for the enhancement of cell electropermeabilization

The use of conductive nanoparticles (NPs) was previously proposed as a way to locally amplify the electric field (EF) intensity at the cell membrane to enhance cell electroporation. To achieve this, a close distance between the NPs and the cell membrane is mandatory. Here, a new method to improve the contact between NPs and cell surface using the effects of electric pulses (electrophoretic forces) is explored. The effects of two types of electric pulses are analyzed alone or combined in a two-pulse-train protocol on Chinese hamster DC-3F cells. Particularly we used 100 ms duration pulses, low intensity-millisecond pulses and combinations of both. Finally, we studied the use of surface coated NPs (PEGylated) for this application. Our results demonstrate that the delivery of an electric field prior to the electroporation pulses increases the accumulation of NPs around the cell membrane suggesting that NPs are pushed towards the cell surface through electrophoretic forces. This allowed reducing the need for long incubations between cells and NPs to observe an enhancement of electroporation mediated by conductive NPs. Thus low intensity-millisecond pulses can be used to increase the accumulation of either aggregated or individual (i.e. PEGylated) NPs supporting the electrophoretic nature of the observed effects. (C) 2020 Published by Elsevier B.V.

Automated summary

This study explores a new method to improve the contact between conductive nanoparticles and the cell membrane using the effects of electric pulses. The results demonstrate that delivering an electric field prior to electroporation pulses can increase the accumulation of nanoparticles around the cell membrane, reducing the need for long incubations between cells and nanoparticles to observe enhanced electroporation.