Endoplasmic reticulum-targeted fluorogenic probe based on pyrimidine derivative for visualizing exogenous/endogenous H₂S in living cells

Developing new probes for visualizing H2S in the endoplasmic reticulum (ER) is of great significance in physiological and pathological fields in that the probe can antagonise ER stress. Herein, we try to explore efficient reporting fluorophores based on three pyrimidine derivatives (L1, L2 and L3), and eventually, a novel probe WH2S was fabricated by using emissive pyrimidine derivative (L1) as the reporting fluomphore. Upon the addition of H2S, the probe processed a thiolytic cleavage to regenerate L1, delivering a remarkable fluorescence enhancement. Probe WH2S presents a perfect selectivity, high sensitivity and low detection limit (3.81 mu M) towards H2S in the buffer media. Most importantly, fluorescence microscopy experiments demonstrate that WH2S can precisely accumulate in ER and detect exogenous/endogenous H2S at cellular level. These results imply that probe WH2S possesses great potentiality in tracking target H2S in complicated and changeable living systems.