A novel dicyanisophorone-based colorimetric and ratiometric fluorescent probe for the detection of hypochlorite in the environment and living cells

A novel dual emissive fluorescent probe SFQ was designed and synthesized by linking dicyanisophorone and thiophene aldehyde units to carbazole groups. The probe SFQ has high selectivity and sensitivity toward ClO- . Upon addition of ClO- to the solution of probe SFQ resulted in a noticeable color changed from orange to pink under natural light. Meanwhile, SFQ could make a ratiometric fluorescence response to ClO- at two different excitation wavelengths, with the change of color from orange-red fluorescence to cyan fluorescence under the 365 nm UV lamp. The detection limit was 1.4 x 10-7 mol/L under ratiometric conditions. The study on the reaction mechanism showed that when SFQ reacted with ClO-, the cyano group disappeared and the cyclic ketone SFQ-O came into being. Furthermore, probe SFQ was successfully used to monitor ClO- in HepG2 cells and detect ClO- in actual environmental water samples.

Automated summary

A novel dual emissive fluorescent probe SFQ was designed and synthesized, which showed high selectivity and sensitivity towards ClO-. The probe exhibited noticeable color changes from orange to pink under natural light and from orange-red fluorescence to cyan fluorescence under a 365 nm UV lamp upon addition of ClO-. It also had a ratiometric fluorescence response to ClO- and a detection limit of 1.4 x 10-7 mol/L. The probe was successfully used to monitor ClO- in HepG2 cells and detect ClO- in actual environmental water samples.