Real time in-situ monitoring of in-flow electroporation using impedance cytometry

Abstract

Electroporation has become a widely adopted method for the intracellular delivery of exogeneous cargo. Its integration with microfluidics and further miniaturization has further consolidated its usefulness, offering more control, efficiency, and viability by performing electroporation on individual cells. The characteristics of the applied electric pulse define the pore formation and are therefore of critical importance for the efficient delivery of cargo while avoiding negative side-effects (e.g. cytotoxicity). One possible method to further improve electroporation is through the implementation of a feedback loop, adjusting the pulse parameters based on electroporation outcome. However, current evaluation methods, like fluorescence microscopy, do not allow for such dynamic optimization scheme. This works aims to monitor the in-flow electroporation process in real time using the impedance cytometry principle. The combination of electroporation and impedance cytometry has been shown before using macroscopic wire electrodes and a constriction channel geometry. Our device further miniaturizes this process by using embedded electrodes inside a microfluidic channel, offering more control and sensitivity, paving the way for a dynamic optimization process.