Visual and quantitative detection of CN- ion in aqueous media by an HBT-Br and thiazolium conjugated fluorometric and colorimetric probe: Real samples and useful applications

Cyanide released from mostly industrial production is a highly toxic chemical. Its heavy industrial use and transportation increase the danger of human exposure. Since it can often lead to rapid death, selective, sensitive and on-site and rapid monitoring techniques for the detection of cyanide are essential. Therefore, we report an efficient cyanide probe based on thiazolium conjugated HBT-Br derivative. It has striking color change toward cyanide blue to yellow under daylight or colorless to cyan under UV-light. Interaction modes of the probe are based on ESIPT and ICT processes. It is selectively able to react free aqueous cyanide with detection limit of 1.79 mu M, lower than physiologically lethal blood levels, >20 mu M. Smartphone assisted and test kit applications are able to detect cyanide, qualitatively. Moreover, real samples such as tap or lake water and apricot seeds including cyanide are successfully determined through the present probe. Therefore, the designed probe displays excellent practical potential toward cyanide.

Automated summary

Cyanide, a highly toxic chemical mainly released from industrial production, requires selective, sensitive, and rapid monitoring techniques for detection. The efficient cyanide probe reported in this study, based on thiazolium conjugated HBT-Br derivative, shows significant color change towards cyanide under different lighting conditions. Through ESIPT and ICT processes, the probe can effectively detect cyanide at levels lower than physiologically lethal concentrations.