A coumarin-based fluorescent probe for imaging H2S and distinguishing breast cancer cells from normal ones

Abstract

Hydrogen sulfide (H2S) is a crucial endogenous gas signal molecule involved in several physiological functions. Elevation of H2S concentrations is considered a cancer biomarker because it may be connected to the growth of tumors. A thorough comprehension of measuring H2S in living cells and differentiating between malignant and normal cells is crucial. Herein, a multi-responsive probe (C-DNP) was constructed to detect H2S and observe the intramolecular charge transfer “turn-off” sensing mechanism caused by the intervention of the irradiative intramolecular charge transfer between C and DNP. Given that DNP recognizes H2S, a reaction between H2S and the probe-attached DNP could eliminate DNP via ether bond breakage and increased emission. Moreover, 1H NMR titrations, HR-MS, and density-functional theory (DFT) calculations confirmed the proposed sensing mechanism. The probe effectively monitored H2S in different water samples, food samples, paper sensor trips, and living cells. Surprisingly, the probe distinguished tumor-bearing cells from normal cells by expressing the variations in H2S both exogenously and endogenously in normal and breast cancer cells. Therefore, it is anticipated to be an efficient method for monitoring H2S in real samples and biosystems.