Important factors for cell-membrane permeabilization by gold nanoparticles activated by nanosecond-laser irradiation

TL;DR

This study demonstrates that antibody-targeted gold nanoparticles activated by nanosecond laser pulses can effectively permeabilize cell membranes and deliver molecules into adherent cancer cells, with efficiency influenced by multiple experimental parameters.

Contribution

It systematically investigates how various conditions affect membrane permeabilization and molecule delivery using laser-activated gold nanoparticles targeting EGFR on cancer cells.

Findings

70% efficiency in delivering 150 kDa dextran into cells

Permeabilization depends on AuNP:cell ratio and incubation conditions

Laser parameters influence permeabilization success

Abstract

Purpose: Pulsed-laser irradiation of light-absorbing gold nanoparticles (AuNPs) attached to cells transiently increases cell membrane permeability for targeted molecule delivery. Here, we targeted EGFR on the ovarian carcinoma cell line OVCAR-3 with AuNPs. In order to optimize membrane permeability and to demonstrate molecule delivery into adherent OVCAR-3 cells, we systematically investigated different experimental conditions. Materials and methods: AuNPs (30 nm) were functionalized by conjugation of the antibody cetuximab against EGFR. Selective binding of the particles was demonstrated by silver staining, multiphoton imaging, and fluorescence-lifetime imaging. After laser irradiation, membrane permeability of OVCAR-3 cells was studied under different conditions of AuNP concentration, cell-incubation medium, and cell - AuNP incubation time. Membrane permeability and cell viability were evaluated by flow cytometry, measuring propidium iodide and fluorescein isothiocyanate - dextran uptake. Results: Adherently growing OVCAR-3 cells can be effectively targeted with EGFR-AuNP. Laser irradiation led to successful permeabilization, and 150 kDa dextran was successfully delivered into cells with about 70% efficiency. Conclusion: Antibody-targeted and laser-irradiated AuNPs can be used to deliver molecules into adherent cells. Efficacy depends not only on laser parameters but also on AuNP:cell ratio, cell-incubation medium, and cell - AuNP incubation time.