Impacts of electrical parameters on the electroformation of giant vesicles on ITO glass chips.

A "sandwich" structure device consisted of ITO electrodes and PDMS spacer was designed and used to explore the impact of different electrical parameters (intensity and frequency) on the electroformation of GUVs (giant unilamellar vesicles). Theoretical analysis of the dielectrophoretic effect (DEPE) and the electrohydrodynamic effect (EHE) on the electroformation process indicated that the characteristic frequency of the system could maximize the mutual effect of the both, which might benefit the formation of GUVs. The calculated value of the characteristic frequency (13.3 kHz) was very close to the experimental one (11 kHz). We demonstrated that for a given electroformation system, large amount of well-distributed GUVs can be obtained by optimizing the electrical parameters. In this paper, when choosing the optimal electrical parameters (11 kHz frequency and 5V/mm intensity), the amount of GUVs could reach 65/mm(2), and the diameters of most GUVs (>70%) were 50-70 μm.