Dynamic fluorescent imaging analysis of mitochondrial redox in single cells with a microfluidic device.

The redox balance in cellular mitochondria is closely related to the physiological and pathological processes of the body. When exposed to external stimuli, the redox state in cells changes dynamically, and presents cell heterogeneity, which creates a need for techniques that can make dynamic and reversible visual analysis of redox in mitochondria at single-cell level. Here we describe a method for single-cell redox analysis based on a microfluidic device combing with a reversible fluorescent probe (Cy-O-ebselen), that enables online culture, labelling and dynamic fluorescent imaging analysis of mitochondrial redox (HO/GSH) change. Using this method, we further explored the dynamic changes of mitochondrial redox state after thermal stimulation or combined thermal-drug stimulation, and analysed the heterogeneous response of cells to external stimuli at the single cell level.