Foster K R, Sowers A E
Department of Bioengineering, University of Pennsylvania, Philadelphia 19041-6021, USA.
Biophys J. 1995 Sep;69(3):777-84. doi: 10.1016/S0006-3495(95)79951-9.
A combined numerical/experimental study is reported of the membrane potentials and dielectrophoretically induced forces between cells, membrane pressures, and velocity of attraction of cells under the influence of an electric field. This study was designed to explore electrical and mechanical effects produced by a field on cells in close proximity or undergoing electrically induced fusion. Laplace's equation for pairs of membrane-covered spheres in close proximity was solved numerically by the boundary element method, and the electrically induced forces on the cells and between cells were obtained by evaluating the Maxwell stress tensor. The velocity of approach of erythrocyte ghosts or fused ghosts in a 60-Hz field of 6 V/mm was measured experimentally, and the data were interpreted by using Batchelor's theory for hydrodynamic interaction of hard spheres. The numerical results show clearly the origin of the dielectrophoretic pressures and forces in fused and unfused cells and the effects of a nearby cell on the induced membrane potentials. The experimental results agree well with predictions based on the simple electrical model of the cell. The analysis shows the strong effect of hydrodynamic interactions between the cells in determining their velocity of approach.
本文报道了一项关于细胞间膜电位、介电泳诱导力、膜压力以及电场影响下细胞吸引速度的数值与实验相结合的研究。该研究旨在探索电场对紧密相邻或正在进行电诱导融合的细胞产生的电学和力学效应。通过边界元法对紧密相邻的成对覆盖膜球体的拉普拉斯方程进行了数值求解，并通过评估麦克斯韦应力张量获得了细胞上以及细胞间的电诱导力。实验测量了红细胞空壳或融合空壳在6V/mm的60Hz电场中的接近速度，并利用巴彻勒关于硬球体流体动力相互作用的理论对数据进行了解释。数值结果清楚地显示了融合和未融合细胞中介电泳压力和力的来源以及附近细胞对诱导膜电位的影响。实验结果与基于细胞简单电学模型的预测结果吻合良好。分析表明细胞间流体动力相互作用对确定其接近速度有很强的影响。
