A Temperature-Ultraviolet-Responsive Fluorescent Anti-Counterfeiting Hydrogel

Area of Science:

• Materials Science
• Chemistry
• Nanotechnology

Background:

• Traditional anti-counterfeiting materials suffer from low responsiveness, easy replication, and poor environmental stability.
• There is a need for advanced materials with multi-stimuli responsiveness for enhanced security and anti-counterfeiting applications.

Purpose of the Study:

• To design and synthesize a novel photothermal-responsive anti-counterfeiting hydrogel with rewritable data storage and multi-level encryption capabilities.
• To overcome the limitations of traditional single-responsive anti-counterfeiting materials.

Main Methods:

• Fluorescein (Flu) was loaded into zeolitic imidazolate framework (ZIF-8) and embedded into a polyacrylamide/lauryl methacrylate (PAM/LMA) hydrogel network.
• The hydrogel's fluorescence properties were modulated by ions (Fe3+ and PO43-) for rewritable data storage.
• Temperature-dependent reversible transparency transitions were achieved using sodium dodecyl sulfate (SDS) and sodium chloride (NaCl) for multi-level encryption.

Main Results:

• The developed hydrogel exhibits intense green luminescence under UV light, which can be reversibly switched by specific ions.
• The material demonstrates temperature-dependent transparency changes, enabling multi-level information encryption.
• The hydrogel is low-toxicity, degradable, and synthesized using an environmentally friendly solvent-free method.

Conclusions:

• A multi-stimuli responsive hydrogel was successfully developed for intelligent anti-counterfeiting.
• This approach offers a promising strategy for creating rewritable, eco-friendly, and secure anti-counterfeiting systems.
• The findings provide a valuable reference for developing multifunctional responsive materials.