Lysosome-Targeted Turn-On Fluorescent Probe for Endogenous Formaldehyde in Living Cells.

As one of the simplest reactive carbonyl species, formaldehyde is implicated in nervous system diseases and cancer. Organelles play crucial roles in various physiological processes in living cells. Accordingly, the detection of endogenous formaldehyde at the subcellular level is of high interest. We herein describe the development of the first organelle-targeted fluorescent formaldehyde probe (Na-FA-Lyso). The new probe exhibits favorable features including a large fluorescence enhancement (about 350-fold) and a fast response to formaldehyde. Significantly, the novel probe Na-FA-Lyso was employed to visualize the endogenous formaldehyde in the lysosomes in living cells for the first time.