A pyrazole-containing hydrazone for fluorescent imaging of Al3+ in lysosomes and its resultant Al3+ complex as a sensor for F−

A fluorescence-enhanced and lysosome-targeted Al3+ probe (1) based on a pyrazole-containing hydrazone was developed in this work. The fluorescent probe 1 displays an OFF–ON fluorescence response to Al3+ in the lysosome pH environment. In addition, the resultant 1–Al3+ complex could act as an ON–OFF fluorescence sensor for F−. Fluorescence imaging shows that 1 is suitable for visualization of Al3+ in lysosomes of HeLa cells.