Eric Mazur

Intracellular cargo delivery with polymer substrates and nanosecond pulsed laser (Conference Presentation)

One major barrier to advancing fundamental studies of biological cargoes for clinical use has been effective delivery into the cytoplasm. Available methods such as electroporation, viral techniques, and liposomal reagents come with respective strengths and weaknesses depending on the application needs. We present a laser-based cargo delivery platform that combines 11-ns laser pulses and structured flexible polymer substrates to create transient pores in the plasma membrane of cells. Cells are grown on the substrates, and pores are induced form on the cells in the regions excited with nanosecond laser pulses—thus, allowing treatment selectivity in a population. The medium surrounding the cell contains the delivery cargoes in solution, and cargoes diffuse into the cell before the transient pores are sealed. Polymer-based substrates are a promising material for laser-based delivery methods because they are low-cost, have flexible spatial movements, and have simple fabrication techniques. We deliver cargos of various sizes. We use fluorescence imaging and flow cytometry to quantify the delivery efficiency and viability in a reproducible manner. We obtain delivery efficiencies of up to 40% with viabilities of 60% for calcein green in adherent cells such as HeLa and Panc-1. We also deliver molecules of up to 40 kDas and siRNA. We use scanning electron microscopy to study cell adherence and substrate surface morphology. Our data shows that polymer-based substrates can deliver biological material directly into cells in a cost-effective manner.