Optimization of cell permeabilization in electron flow based mitochondrial function assays

Permeable cell models have contributed much to the progress in mitochondrial research. Optimization of permeabilization is required to make the cell's plasma membrane permeable to small molecules while keeping the intracellular organelles and their membranes intact and fully functional. Here we report our assessment and optimization of commonly used permeabilizing agents including different saponin preparations, digitonin, and recombinant perfringolysin O employing a new electron flow based mitochondrial assay technology that utilizes a colorimetric redox dye. The results of this study provide guidance in optimizing the conditions for mitochondrial function assays with permeabilized cells using the novel redox dye-based format.