Engineered water-soluble photosensitive fluorescent probes of β-galactosidase with fast response based on triarylboron compound derivatives for ovarian cancer cell imaging

β-Galactosidase is a primary biomarker for ovarian cancer, which poses a serious threat to the health of women. Herein, we report the design and synthesis of three fluorescent probes for β-galactosidase based on triarylboron (TAB): TAB-2-Gal, TAB-4-Gal, and TAB-6-Gal. The performance of these probes was tuned by changing their structure. They demonstrate excellent water solubility and fast responses, superior to most of the previously reported properties of existing β-galactosidase probes. In particular, using TAB-4-Gal the entire recognition process can be completed within 4 min and this probe produces the greatest fluorescence signal. As TAB-4-Gal possesses a piperazine group in its structure, it better able to locate lysosomes and produces a strong fluorescence signal from ovarian cancer cells. Thus, it is an ideal fluorescent probe for distinguishing ovarian cancer cells from other cells. Moreover, the high photosensitivity of TAB-4-Gal means that it can also selectively induce apoptosis of ovarian cancer cells under low-intensity visible light irradiation (1.5 mW/cm2).