A triphenylamine-based fluorescence probe for detection of hypochlorite in mitochondria

The level of HClO/ClO^- in mitochondria is essential to keep the normal function of mitochondria. Therefore, it is meaningful to accurately and quickly monitor ClO^- in mitochondria. In this work, a new triphenylamine-based fluorescence probe PDTPA was designed and synthesized, in which pyridinium salt and dicyano-vinyl group were introduced as mitochondria targeting site and reaction site for ClO^-. The probe showed high sensitivity and fast fluorescence response (<10 s) in the detection of ClO^-. Moreover, the probe PDTPA had good linearity in a wide concentration range of ClO^- and its detection limit was calculated as 10.5 μM. Confocal fluorescence images demonstrated that the probe could target mitochondria and track the fluctuations of endogenous/exogenous ClO^- levels in the mitochondria of living cells.