A new gelator based on tetraphenylethylene and diphenylalanine: Gel formation and reversible fluorescence tuning

A new gelator 1 based on tetraphenylethylene (TPE) and diphenylalanine was designed and synthesized. Compound 1 was non-emissive in solution, but its fluorescence turned on after the formation of gels, due to the aggregation-induced emission (AIE) feature of TPE. Interestingly, the fluorescence was reversibly switched on-off upon the gel-sol transition. Scanning electron microscope (SEM), confocal laser scanning microscope (CLSM) and X-ray diffraction (XRD) were employed to study the gels.