Chemodosimeters and 3D inorganic functionalised hosts for the fluoro-chromogenic sensing of anions

We report here recent examples developed in our research group on the development of novel chemodosimeters for fluoro-chromogenic anion sensing. For instance, squaridine, pyrylium and pent-2-en-1,5-dione dye scaffoldings have been used to obtain highly specific chromo-fluorogenic responses for anions such as cyanide, sulfide or certain carboxylates in water or mixed aqueous solutions. We will also report new examples on the use of “smart sensory materials” based on nanoscopic inorganic structures as bio-mimetic hosts for anion sensing. These systems combine molecular ideas and 3D solid pre-organised features as new design concepts for the development of organic/inorganic hybrid materials for recognition/sensing protocols. For instance, the functionalisation of siliceous mesoporous materials with ureas, thioureas, guanidinium groups or saccharides and suitable dyes has resulted in enhanced fluoro-chromogenic sensing of anionic species such as fatty acids, citrate or borate.