University of Ljubljana, Faculty of Electrical Engineering, Slovenia.
Institute of Chemical Technologies and Analytics, TU Wien, Vienna, Austria.
Bioelectrochemistry. 2023 Oct;153:108498. doi: 10.1016/j.bioelechem.2023.108498. Epub 2023 Jun 29.
Electroporation is a useful tool for the manipulation with the cell membrane permeability. Underlying physicochemical processes taking place at the molecular level during electroporation are relatively well studied. However, various processes remain unknown, one of them is lipid oxidation, a chain reaction that causes degradation of lipids, and might explain the long-lasting membrane permeability after the electric field has ceased. The aim of our study was to observe the differences in the electrical properties of planar lipid bilayers, as in vitro cell membrane models, due to lipid oxidation. Phospholipids were chemically oxidized and oxidation products were analysed using mass spectrometry. Electrical properties, resistance R (Ω) and capacitance C (F) were measured using an LCR meter. Using a previously developed measuring device, a linear increasing signal was applied to a stable bilayer in order to measure its breakdown voltage U (V) and lifetime t (µs). We observed an increase in conductance and capacitance of the oxidized planar lipid bilayers when compared to their non-oxidized counterparts. With increasing lipid oxidation, the core of the bilayer becomes more polar, and consequently more permeable. Our findings can explain the long-lasting permeability of the cell membrane after electroporation.
电穿孔是一种用于改变细胞膜通透性的有用工具。在分子水平上发生的电穿孔的基础理化过程已经得到了较为充分的研究。然而，仍有许多过程不为人知，其中之一是脂质氧化，这是一种引发脂质降解的链式反应，可能解释了电场停止后细胞膜通透性的持久存在。我们的研究目的是观察由于脂质氧化，作为体外细胞膜模型的平面脂质双层的电学性质的差异。使用质谱分析法对磷脂进行化学氧化，并分析氧化产物。使用 LCR 表测量电阻 R（Ω）和电容 C（F）。使用之前开发的测量装置，将线性递增信号施加到稳定的双层上，以测量其击穿电压 U（V）和寿命 t（µs）。与未经氧化的脂质双层相比，我们观察到氧化后的平面脂质双层的电导率和电容增加。随着脂质氧化的增加，双层的核心变得更加极性，因此更具渗透性。我们的发现可以解释电穿孔后细胞膜的持久通透性。
