Background: Liposomes have been a useful tool to analyze membrane behavior. Various studies have attempted to induce biological activities, for example, buddings, divisions, and endocytosis, on liposomes, focusing on lipid rafts that move along electric fields. Materials and Methods: Liposomes consisting of soybean lecithin, phosphatidylcholine, and cholesterol were prepared, with inner and outer liquid conductivities of 0.595 and 1.564 S/m, respectively. Results: We tried to induce buddings by pulsed electric fields (PEFs) on liposomes. Results demonstrated that 1.248 kV/cm, 400 ls PEF promoted postpulse liposome buddings, which were preceded by a membrane relaxation. Although a transient thick area (a lipid raft-like area) on the membrane just after PEF application preceded buddings, it was not the sufficient factor for buddings. Conclusion: We established a brief model as follows: 1.248 kV/cm, 400 ls PEF induced the lipid membrane relaxation without electroporation to trigger buddings. The current results could be a new frontier in bioelectrics.

15Liposomes are widely assumed to present a straightforward physical model of cells. 16However, almost all previous liposome experiments with pulsed electric fields (PEFs) 17 have been conducted in low-conductivity liquids, a condition that differs significantly 18 2 from that of cells in medium. Here, we prepared liposomes consisting of soy bean 19 lecithin and cholesterol, at a molar ratio of 1:1, in higher-conductivity liquid that 20 approximated the conditions of red blood cells in phosphate-buffered saline, with inner 21 and outer liquid conductivities of 0.6 and 1.6 S/m, respectively. We found that a single 22 1.1 kV/cm, 400 s PEF promoted cell-like spontaneous division of liposomes. 23 24