Self-assembled natural biomacromolecular fluorescent hydrogels with tunable red edge effects

[Display omitted] •Develop new fluorescent hydrogel via multi-components.•The prepared fluorescent hydrogel has "red edge effect", which don’t disappear by pH and concentration changes.•Potential applications of alternative fluorescent probes. At present, fluorescent hydrogels have attracted more and more attention due to their wide applications in medical diagnosis, biological imaging and drug delivery. However, the luminescence of traditional fluorescent hydrogels usually requires specific fluorophores, and most of the fluorophores were rigid planar structures containing benzene rings or heterocyclic structures, making traditional fluorescent hydrogels have higher cytotoxicity and lower water solubility, thus limiting their practical applications. Here, we reported a fluorescent hydrogel, which can generate hydrogen bonds without emitting specific fluorophores, and it was found that the fluorescence intensity could be strengthened with the increase of concentration. At the same time, the fluorescence emission peak has the response of excitation wavelength and is not affected by the pH and concentration. Therefore, this special discovery in present work opens new application prospects for fluorescent hydrogels.