Injectable, degradable, electroactive nanocomposite hydrogels containing conductive polymer nanoparticles for...

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Nanotechnology

Background:

• Injectable electroactive hydrogels (eGels) are crucial for regenerative medicine and drug delivery.
• Achieving eGels with uniform structure, degradability, robustness, and biocompatibility remains a challenge.
• Incorporating functional nanoparticles is a strategy to enhance hydrogel properties.

Purpose of the Study:

• To synthesize and characterize novel injectable electroactive hydrogels (eGels).
• To reinforce oxidized alginate-gelatin hydrogels with electroactive tetraaniline-graft-oxidized alginate nanoparticles (nEOAs).
• To evaluate the impact of nEOAs on hydrogel properties, including electroactivity, mechanical strength, and biocompatibility.

Main Methods:

• Synthesis of tetraaniline-graft-oxidized alginate nanoparticles (nEOAs).
• Formation of injectable hydrogels by crosslinking oxidized alginate with gelatin, incorporating nEOAs.
• Characterization using transmission electron microscopy, (1)H nuclear magnetic resonance, dynamic light scattering, rheometry, and scanning electron microscopy.
• Assessment of mechanical strength, conductivity, degradation, cell viability, and in vivo biocompatibility.

Main Results:

• nEOAs self-assembled into stable nanoparticles and were successfully incorporated into the hydrogel network without phase separation.
• The resulting eGels exhibited improved mechanical strength (up to ~8 kPa) and conductivity (up to ~10(-6) S/cm).
• The eGels demonstrated injectability, uniformity, degradability, and good in vitro and in vivo biocompatibility with mesenchymal stem cells and chick chorioallantoic membranes.

Conclusions:

• The developed nEOA-reinforced eGels possess a combination of desirable properties including injectability, electroactivity, mechanical robustness, degradability, and biocompatibility.
• These eGels hold significant potential as advanced scaffolds for tissue regeneration applications.
• The eGels are also suitable as matrices for stimuli-responsive drug release systems.