A rational designed fluorescent and colorimetric dual-channel sensor for cyanide anion based on the PET effect in aqueous medium

•A novel sensor for highly selective and sensitive detection of CN via its promising photo-induced electron transfer (PET) feature.•This sensor displayed dual-channel response to CN in EtOH/H2O (7:3, v/v) HEPES solution, and have strong anti-interference toward other common anions.•The sensor was successfully applied to detect CN in food samples.•The test strips could conveniently and rapidly (within a short time of 3 s) detect CN in aqueous medium.

A fluorescent and colorimetric sensor based on naphtho[2,1-b]furan-2-carbohydrazide and 2-hydroxy-1-naphthaldehyde (Q1-1) was developed via straightforward reaction from inexpensive reagents. It exhibited rapid response, superb selectivity, and swift sensitivity toward CN based on its promising photo-induced electron transfer (PET) feature. Q1-1 not only can sense CN through sharp colorimetric and selective turn-on fluorescence dual-channel responses in EtOH/H2O (7:3, v/v) HEPES solution, but also have strong anti-interference toward other common anions, especially the basic anions such as F−, AcO−, H2PO4− and SCN−. Notably, this sensor was successfully applied to detect CN− in food samples, which proves a very simple and selective platform for on-site monitoring of CN− in agriculture samples. In addition, the test strips based on Q1-1 were fabricated, which could act as convenient and efficient CN− test kits.

Graphical abstractA fluorescent and colorimetric sensor based on naphtho[2,1-b]furan-2-carbohydrazide and 2-hydroxy-1-naphthaldehyde (Q1-1) was developed via straightforward reaction from inexpensive reagents. The sensor Q1-1 exhibited rapid response, superb selectivity, and swift sensitivity toward CN based on its promising photo-induced electron transfer (PET) feature.Download high-res image (116KB)Download full-size image