Phenazine methosulfate is widely used as an electron carrier in biochemical assays, particularly in studies involving redox reactions. It plays a crucial role in facilitating the transfer of electrons between enzymes and substrates, making it valuable in assays like the MTT assay for measuring cell viability and metabolic activity. Additionally, it is employed in the study of mitochondrial function and oxidative phosphorylation, helping researchers understand cellular respiration processes. Its ability to act as a mediator in electrochemical sensors also makes it useful in biosensor development for detecting various analytes.