Electroformation of giant unilamellar vesicles using interdigitated ITO electrodes

A coplanar interdigitated electrode was used as a new electrode system to form giant unilamellar vesicles (GUVs). The formation of GUVs using interdigitated electrodes was investigated in detail with respect to various parameters, including solution height, electrode width, the amplitude and frequency of AC fields, and temperature. Interdigitated electrodes with smaller widths generated bigger GUVs under the same conditions. According to both experimental and 3D field simulation results, a solution height above 600 μm has no influence on the GUV formation. GUVs were obtained within a wide range of frequency from 1 Hz to 10⁴ Hz and field amplitude from 1 V to 10 V. The diameters of the GUVs decreased with increasing frequency at a constant amplitude, and increased with increasing amplitude from 1 V to 5 V and then decreased from 5 V to 10 V at 10 Hz. A phase diagram based on varying the AC frequency and amplitude was obtained experimentally, which can be used to predict the electroformation of GUVs.