Irreversible electroporation (IRE) is a technique for the disruption of localized cells or vesicles by a series of short and high−frequency electric pulses which has been used for tissue ablation and treatment in certain diseases. It is well reported that IRE induces lateral tension in the membranes of giant unilamellar vesicles (GUVs). The GUVs are prepared by a mixture of anionic lipid dioleoylphosphatidylglycerol (DOPG) and neutral lipid dioleoylphosphatidylcholine (DOPC) using the natural swelling method. Here the influence of DOPG mole fraction, X_DOPG, on the critical tension of electroporation in GUVs has been investigated in sodium chloride-containing PIPES buffer. The critical tension decreases from 9.0 ± 0.3 to 6.0 ± 0.2 mN/m with the increase of X_DOPG from 0.0 to 0.60 in the membranes of GUVs. Hence an increase in X_DOPG greatly decreases the mechanical stability of membranes. We develop a theoretical equation that fits the X_DOPG dependent normalized critical tension, and obtain a binding constant for the lipid-ion interaction of 0.75 M⁻¹. The decrease in the energy barrier for formation of the nano−size nascent or prepore state, due to the increase in X_DOPG, is the main factor explaining the decrease in critical tension of electroporation in vesicles.

不可逆电穿孔 (IRE) 是一种通过一系列短高频电脉冲破坏局部细胞或囊泡的技术，已用于组织消融和某些疾病的治疗。据报道，IRE 会引起巨型单层囊泡 (GUV) 膜的侧向张力。 GUVs由阴离子脂质二油酰磷脂酰甘油(DOPG)和中性脂质二油酰磷脂酰胆碱(DOPC)的混合物采用自然溶胀法制备。这里，在含有氯化钠的 PIPES 缓冲液中研究了 DOPG 摩尔分数X _DOPG对 GUV 电穿孔临界张力的影响。随着 GUV 膜中X _DOPG从 0.0 增加到 0.60，临界张力从 9.0 ± 0.3 降低到 6.0 ± 0.2 mN/m。因此， X _DOPG的增加大大降低了膜的机械稳定性。我们开发了一个适合X _DOPG依赖的归一化临界张力的理论方程，并获得了 0.75 M ^-1的脂质-离子相互作用的结合常数。由于X _DOPG的增加，形成纳米级新生或预孔状态的能量势垒降低，这是解释囊泡中电穿孔临界张力降低的主要因素。