Involvement of membrane proteins and ion channels on the self-rotation of human cells in a non-rotating AC electric field

摘要

Dielectrophoresis is a force that has been exploited in microsystems for label-free characterization and separation of cells, when their electrical signature is known. However, the polarization effect of cells at the transmembrane protein level is not well established. In this work, we have use the self-rotation effect of cells in a non-rotating field, known as the Quincke effect, in order to measure the maximum rotation frequency (f(rotmax)) of different cell populations when modifying the composition of their membrane. We investigated the influence of active ionic transportation of membrane protein concentration on f(rotmax) of HEK cells. Our results show that ionic transportation is responsible for the reduction of conductivity within the cytoplasm, which results in higher f(rotmax). However, the influence of the concentration of proteins in the membrane, achieved by silencing gene expression in cancer cells, changes significantly f(rotmax), which is not explained by the changes of ionic conductivity within the cell.