A microfluidic device for electrofusion of biological membranes

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 /spl mu/m 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 up 75% and is globally better for liposome diameters larger than 10 /spl mu/m. The encapsulation of microbeads inside liposomes has been also demonstrated and opens up the route towards fusion-based delivery of artificial microstructures into cells.