A microfluidic device for electrofusion of biological vesicles.

This paper reports a microfabricated device with high aspect-ratio electrodes and low power consumption for the electrofusion of liposomes and cells. The applications may range from gene transfection or cell tracking to biophysical studies of membrane proteins. The device consists of 250 microm thick silicon electrodes bonded to a glass substrate and covered by a PDMS-coated glass slide. Liposomes were first aligned by AC voltage at 300 kHz and then fused with short DC pulses. The fusion yield can reach 75% and is globally better for liposome diameters larger than 10 microm. The encapsulation of microbeads inside liposomes has also been demonstrated and opens up the route towards fusion-based delivery of artificial microstructures into cells.