Azo based organogelators for selective recognition of arginine and cystein in aqueous alcoholic media

Two novel azo-based photo-responsive supramolecular organogelators, containing formyl group was synthesized from readily available starting materials and characterized through, rheological, and spectroscopic measurements. The gelators were found to be capable of forming gels in light alcohols and alcohol/water mixtures at low concentrations. The sol-gel behavior of these low molecular weight gelators in response to temperature, UV–Vis light irradiation, and in the presence of various essential amino acids was studied. Our investigations on the gelator sensing abilities revealed that, in addition to the photo-responsive function due to the presence of azo moiety, the ethanol/water gel of one of as synthesized compounds exhibited excellent ability to detect l-arginine among ۱۹ various amino acids, via gel to sol transition and colour change. Furthermore, the gelator could successfully recognize l-cysteine among ۱۹ amino acids, through macroscopic sol to gel transition and colour change of its alkaline methanolic solution

Keywords:

arginine , azo compounds , chemosensors , cysteine , gels , supramolecular chemistry