Development of a Long-Lived Luminescence Probe for Visualizing β-Galactosidase in Ovarian Carcinoma Cells.

β-Galactosidase (β-gal) is an important biomarker for ovarian cancers. In this work, we designed and synthesized a novel iridium(III)-based probe 1 for discriminating ovarian carcinoma cell lines from normal cell lines. The probe could detect β-gal even in the presence of a highly autofluorescent background. The probe also showed a good linear response to β-gal between 0 and 30 U/mL, with a detection limit of 0.51 U/mL. Importantly, complex 1 could selectively "light up" ovarian carcinoma cells, while exhibiting negligible luminescence in normal cells. Overall, complex 1 could be potentially used as a useful probe for detecting β-gal expression in the context of ovarian cancer diagnostics.