Abstract/Summary

A histidine‐containing bola‐amphiphilic molecule (NDIP) containing a peptide‐appended naphthalenediimide (NDI) forms fluorescent hydrogels in phosphate buffer and organogels with benzenoid solvents. These gels were characterized by several spectroscopic and microscopic techniques including FT‐IR, HR‐TEM, powder X‐ray diffraction and small‐angle X‐ray scattering, UV‐Vis and fluorescence studies. The gelator molecule exhibits no significant fluorescence in the xerogel state, while it shows a significant fluorescence (bright cyan) in the presence of volatile organic/inorganic acid vapors; this cyan color vanishes in presence of base (ammonia vapors). A reusable paper‐strip‐based method based on this self‐assembled fluorescent material can be used to easily detect hazardous volatile acid and base vapors with the naked eye.