Search

In this paper, we developed a red-emitting fluorescent probe TPSN based on triphenylamine-functionalized benzothiazole salts. TPSN exhibits a strong luminescence emission at about 637 nm in viscous media. Moreover, the fluorescence intensity of TPSN enhances approximately 94-fold from water to 99% glycerol. Cell imaging experiments reveals that TPSN presents high specificity for mitochondrial localization. The related mechanism study indicates that the localization property of TPSN is independent of the mitochondrial membrane potential. As a result, TPSN offers a promising tool to monitor the mitochondria viscosity in living cells.

In this paper, two novel benzothiazole derivatives EtSN and OAcSN with a D–π–A configuration were developed as fluorescent probes for the detection of HSO3−. Compared with OAcSN, probe EtSN, bearing ester group, displayed a lower detection limit and faster response time. Upon treatment with HSO3−, EtSN and OAcSN displayed noticeable color change from yellow (EtSN)/red (OAcSN) to coreless, respectively. Competitive experiments indicated that EtSN and OAcSN had higher fluorescence selectivity towards HSO3− than other analytes. The sensing mechanism was further illustrated by 1H NMR and TD-DFT.

A novel water-soluble fluorescent probe L based on indole salts has been designed, synthesized and fully characterized. The systematic investigations demonstrated that probe L shows red emission and the fluorescence intensity is linear with the viscosity of the medium. Probe L is able to selectively accumulate in mitochondria within 1 min without any additional reagents for membrane permeabilization. It has been used to distinguish the viscosity differences between mitochondria in normal and nystatin-treated HeLa cells. In addition, due to the good photostability, probe L can be used to monitor the dynamics of mitochondria. These results support that probe L might provide a promising approach for the fluorescence detection of mitochondrial viscosity in living biological systems.

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 fluorophore. 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 μM) 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.