Plasmonic Cell Transfection using Micropyramid Arrays

We present a new cell transfection method that uses femtosecond laser-excited localized surface plasmons (LSPs) on a nanostructured micropyramid array. Our gold-layered micropyramids have nano-apertures at the apex to form high local electric field enhancements, or “hot spots.” These hot spots form microbubbles that temporarily perforate mammalian cell (HeLa S3) membranes and allow dye molecules and plasmid vectors to diffuse through the membrane openings. We introduce an emerald green fluorescent protein (EmGFP) reporter plasmid into the cells to determine the LSP-mediated transfection efficiency of the substrate. We optimize our laser parameters for successful transfection and high cell viability. Our nontoxic, efficient, and scalable technique offers an innovative approach to the advancement of regenerative medicine and the study of LSP-cell interaction.