Binding interactions and sensing applications of chromone derived Schiff base chemosensors via absorption and emission studies: A comprehensive review

[Display omitted] •The review contains different experimental procedures and sensing mechanisms followed in fluorescence sensing.•This review paper compiles the synthesis of different formylchromones.•Chromones Schiff bases are efficient colorimetric and fluorescent sensors.•Chromone-based Schiff base sensors has found practical applicability’s in environmental and biological samples. Chemosensors are the molecular probes which are frequently used for analyte (metal ions, anions, explosives etc.) detection via photophysical changes. Analyte detection constitutes an active topic of research because the imbalanced consumption of these chemical species produces harmful effects to the ecosystem as well as to living beings. In recent years, several molecular probes of different frameworks are known for analyte detection. Among these, Schiff bases are more proficient and effective as compared to other chemosensors. Chromones itself possessing various physiological and photochemical properties but introduction of azomethine bond in chromones makes it useful probe for sensing applications. Colorimetric and fluorimetric sensing are promising techniques used to detect different chemical species in solvent system. They provide high sensitivity, reliability and quick response in comparison to the other reported techniques. The motive of this review is to provide better insight of the sensing mechanism of chromone derived Schiff bases and their practical utility in analyte detection to the researchers.