Understanding ion transport by quantification of mitochondrial swelling

Suspensions of mitochondria are turbid and scatter light. An increase in the matrix volume (swelling) due to the influx of permeable solutes results in a decrease in the amount of light scattered. This property can be used to study solute fluxes across the mitochondrial inner membrane. A rapid method for isolating mitochondria is presented along with three swelling experiments using energized and non-energized mitochondria to illustrate ion transport across energy transducing membranes.