Covalent bond formation as an analytical tool to optically detect neutral and anionic analytes

The article gives an overview on new indicator dyes that recognize analyte molecules via chemical reactions. Chemosensor molecules for neutral analytes such as amines, alcohols, aldehydes, carbon dioxide, saccharides, thiols and for ionic analytes such as hydrogen sulfite, hydrogen sulfide, cyanide, or amino acids are presented. Their possible application for optical sensing is discussed as well are response mechanism, selectivity and sensitivity.