Ultrasensitive two-photon probes for rapid detection of β-galactosidase during fruit softening and cellular senescence

Senescence is happening in every corner of the living organisms. β -galactosidase ( β -gal) is one of the most important biomarkers during senescence in both plant and mammalian cells. Most β -gal fluorescent probes were focused on bio-imaging, only a few probes were developed for the detection of β -gal in fruit, and the probes that could detect β -gal in both fruits and living cells were even less. Here, two β -gal probes ( TNap-βGal and TBNap-βGal ) were synthesized, which can not only image the increase of β -gal during both fruits softening and cellular senescence, but also prove that bananas are not suitable for storage in refrigerator and the subsequent accumulation of β -gal still in lysosome of mammalian cells. In addition, TNap-βGal was successfully applied to two-photon imaging of endogenous β -gal in both hDPMSCs and tissues of human dental pulp for the first time.