( Invited ) Designing Dynamic and Self-Powered Biomaterials for Biomedical Applications

Abstract

Regenerative medicine is vital for restoring tissue function and health; however, conventional biomaterials typically remain static or rely on external energy sources, limiting their functionality in dynamic biological environments. Here, we introduce a novel approach to fabricate dynamic, self-folding biomaterials via 4D printing, overcoming these limitations. Using an extrusion-based multi-material 4D printing technique, we engineer perfusable, shape-morphing hydrogel scaffolds composed of an alginate/methylcellulose system enhanced with carbonized alginate nanoparticles. These scaffolds exhibit programmed swelling-driven shape transformations and possess anti-oxidative, anti-inflammatory, and anti-thrombotic properties, promoting cell viability and mimicking complex vascular architectures. In parallel, we develop solvent-cast chitosan films with enhanced aqueous stability and intrinsic piezoelectricity that autonomously convert biomechanical energy into electrical signals, stimulating cell proliferation and migration without external power. Despite chitosan being a well-known natural polymer, its piezoelectric application has been limited due to low piezoelectric coefficients and rapid degradation in aqueous environments. Our approach overcomes these challenges by alkaline cross-linking to improve stability and mechanical properties, enabling effective self-powered bioelectrical stimulation. Together, these innovations establish a self-powered, dynamic biomaterial platform capable of mimicking native tissue mechanics and bioelectric cues, marking a significant advance toward next-generation tissue regeneration therapies.