Construction of polymethine chain modified pentamethylene cyanine dyes for G-quadruplex imaging in live cells

Here, a supramolecular strategy that relies on the G-quadruplex DNA recognition-driven disaggregation of pentamethylene cyanine Cy5-ph-H aggregates is outlined, which can turn on its fluorescence and be used to visualize G-quadruplex DNA in living cells and highly target mitochondria.