Biointegrated Conductive Hydrogel for Real-Time Motion Sensing in Exoskeleton-Assisted Lower-Limb Rehabilitation.
Ming Li1,2,3, Hui Li1,2,3, Yujie Su4
1Institute of Intelligent Rehabilitation Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China.
Sensors (Basel, Switzerland)
|November 13, 2025
Summary
A new biointegrated hydrogel (CPSD) enables wound healing and real-time physiological monitoring during exoskeleton rehabilitation. This advanced material offers superior adhesion and sensing for closed-loop systems.
Area of Science:
- Biomaterials Science
- Regenerative Medicine
- Wearable Technology
Background:
- Chronic lower-extremity wounds require advanced dressings for healing and monitoring during rehabilitation.
- Existing wound dressings and conductive hydrogels have limitations in dynamic sensing, adhesion, and electronic performance.
Purpose of the Study:
- To develop a biointegrated hydrogel (CPSD) for simultaneous wound protection and physiological monitoring in exoskeleton-assisted rehabilitation.
- To evaluate the material properties, biocompatibility, and sensing capabilities of the novel hydrogel.
Main Methods:
- Fabrication of the CPSD hydrogel using carboxymethyl chitosan (CMCS), PEDOT:PSS, and dopamine-functionalized sodium alginate (SD).
- Characterization of hydrogel properties including swelling, mechanical integrity, conductivity, adhesion, and water vapor transmission rate (WVTR).
- In vitro testing for antioxidant, antibacterial, cytocompatibility, and hemocompatibility.
- Integration and testing of CPSD hydrogels in a lower-limb exoskeleton for motion and electromyography (sEMG) sensing.
Main Results:
- The CPSD hydrogel demonstrated tunable swelling, stable mechanical properties, high photothermal conversion, potent antioxidant and antibacterial activity (>90% under NIR).
- Achieved bulk conductivity of ~1.6 S·m-1, compressive modulus of ~15 kPa, lap-shear adhesion of ~9.5 kPa on porcine skin, and WVTR of ~75 g·m-2·h-1.
- Successfully captured electromyographic and strain signals during exoskeleton-assisted motion, enabling movement-intent detection.
Conclusions:
- The CPSD hydrogel is a multifunctional material suitable for advanced wound care and real-time physiological monitoring.
- This material supports stable biointerfaces for sensing applications in closed-loop rehabilitation and mobile health.
- CPSD hydrogels represent a promising advancement for next-generation rehabilitation systems.
