A novel colorimetric and ratiometric fluorescent CN− sensor based on rhodamine B hydrazone derivatives in aqueous media and its application in sprouting potatoes.

A novel highly selective chemosensor Z based on rhodamine B hydrazone derivatives was designed and synthesized, and it showed both colorimetric and “turn-on” fluorescence responses for CN− in an aqueous solution. The results showed that after adding CN− ions in aqueous solution, the chemosensor Z showed significant color change from colorless to pale-yellow, which was visible to the naked eye, and it rapidly produced strong green fluorescence. The probe could distinguish CN− by deprotonation and intramolecular charge transfer (ICT) mechanisms, as evidenced by 1H-NMR titration and DFT calculations. In addition, the detection limit of the fluorescence response of the sensor for CN− was 5.81 × 10−8 M, which was measured by titration. The chemosensor Z has been successfully used to detect CN− in sprouting potatoes. Z-containing test strips have also been prepared, and they can be used as a colorimetric tool for CN− detection in potential applications. [ABSTRACT FROM AUTHOR]