The compounds of 3-aminopyridine-2-carboxylic acid with K+ (1) and Zn2+ (2) were found to be AIE-active. The AIE behaviours could be attributed to the restriction of intramolecular rotation (RIR) and vibration (RIV) via hydrogen bonds, resulting in rigidity enhancement of the molecules. An AIE-based fluorescence turn on chemosensor for the Zn(II) ion has been developed in aqueous media with high selectivity and sensitivity.
