Analysis of Membrane potential by Flow Cytometry (CAT#: STEM-CBT-0068-WXH)

Introduction

Electrical potential differences are present across the cytoplasmic membranes of most living prokary otic and eukaryotic cells and also between the cytosol and the interior of organelles such as chloroplasts and mitochondria. Membrane potential (ΔΨ) is generated and maintained by concentration gradients of ions such as sodium, potassium, chloride, and hydrogen. Changes in cytoplasmic ΔΨ in the course of surface-receptor-mediated processes related to the development, function, and pathology of many cell types often play a role in transmembrane signaling. Cytoplasmic ΔΨ is also reduced to zero when the membrane is ruptured by chemical or physical agents. Mitochondrial ΔΨ is reduced when energy metabolism is disrupted, notably in apoptosis. In bacteria, which lack mitochondria, ΔΨ reflects both the state of energy metabolism and the physical integrity of the cytoplasmic membrane. Flow cytometry can be used to estimate membrane potential in eukaryotic cells, mitochondria in situ, isolated mitochondria, and bacteria.