pH and Thermo Dual-Responsive Fluorescent Hydrogel Actuator.

Area of Science:

• Materials Science
• Polymer Chemistry
• Smart Materials

Background:

• Fluorescent hydrogel actuators are key smart materials, exhibiting color and shape changes in response to external stimuli.
• Developing dual-responsive actuators with combined fluorescence and actuation capabilities is an active research area.

Purpose of the Study:

• To develop a novel fluorescent hydrogel actuator with dual pH and thermo responsiveness.
• To integrate pH-responsive perylene tetracarboxylic acid (PTCA) with aggregation-caused quenching (ACQ) effect into a thermoresponsive polymer structure.

Main Methods:

• Incorporation of pH-responsive PTCA into an anisotropic poly(N-isopropylacrylamide)-polyacrylamide (PNIPAm-PAAm) hydrogel.
• Characterization of thermoresponsive shape deformation and switchable fluorescence performance.
• Investigation of dual stimuli-responsive behavior for information encoding and hiding.

Main Results:

• The developed hydrogel exhibits stable thermoresponsive shape deformation.
• Switchable fluorescence performance is achieved upon a pH trigger due to the ACQ effect of PTCA.
• Actuation-based information hiding is demonstrated by utilizing thermoresponsive shape changes.

Conclusions:

• The novel fluorescent hydrogel actuator demonstrates dual pH and thermo responsiveness.
• The material integrates fluorescence-quenching and actuation mechanisms for advanced functionalities.
• This work provides insights into designing and preparing novel stimuli-responsive hydrogel actuators.