Prof. Hui-wang Ai and colleagues at UCR have developed a new near-infrared fluorescent MMP probe that provides a number of advantages over current probes. Due to its improved chemistry the new probe, named NIMAP, delivers high sensitivity given its high fluorescence contrast and low background fluorescence. It has optimal emissions (above 600 nm) for mammalian in vivo and in vitro studies and improved accumulation within mitochondria which improves its quantitative analysis possibilities. NIMAP is also extremely photostable and can be utilized to monitor MMP for an extended period. Given these properties, NIMAP may be a powerful tool for studying MMP and mitochondrial function in various biological settings.