Molecule delivery by photoporation mediated by gold nanoparticles

Abstract

There are many situations in medicine and biology when it is desirable to introduce a macromolecule into mammalian cells. Gold nanoparticles mediated photoporation is a promising technique that is an efficient, relatively high-throughput and virus-free method. Up to now different pulse laser and kinds of gold nanoparticles with different size, different shape were employed to achieve photoporation for macromolecule delivery such as dextran, protein and plasmid. Here, gold nanosphere and nanorod activated by nanosecond laser were used to improve permeability of membrane, fluorescence labeled dextran and antibody were delivered into cells. The influence of laser parameters and the micro-environment around cells were analyzed, the results showed that concentration of gold nanoparticles is important for photoporation, the cells is easy to die with higher concentration above 104 gold nanoparticles per cell that corresponding to a narrow irradiation fluence. Results also demonstrated that for cells incubated in PBS, successful permeabilization was observed at lower irradiation fluence than cells incubated in RPMI medium. During irradiation the micro-phenomena was observed by homemade plat, we found that the vapor bubble generation around gold nanoparticles is the main mechanism of the photoporation, and the properties of these nanobubbles are highly dependent on the size of the nanoparticles and the properties of the laser pulse according to extended two-temperature model. In addition, a diffusion model that based on measuring resealing time invasively, was established to assess the loading efficiency, results showed that this approach is an ideal and accurate estimation of the loading efficiency of cells by photoporation for accounting hole-resealing dynamics.