Biological Complexity-Inspired Engineering of Tough and Anisotropic Protein-Based Materials for Adaptive Sensing

Biological systems inspire the design of high-performance biomimetic materials, yet replicating their synergistic interactions and hierarchical structures remains challenging. Here, we present an orthogonal photochemistry-mediated strategy for one-step fabrication of muscle-inspired protein materials. This approach integrates covalent, electrostatic, and hydrogen-bonding interactions to form robust multinetwork architectures within hierarchically organized protein matrices. Prestretching enhances molecular alignment, yielding anisotropic materials with a factor of 3.0, tensile strengths up to 300 MPa, toughness over 22 MJ m^-3, and a fatigue threshold of 760 J m^-2─surpassing natural proteins such as wool, cotton, and silk. The rapid (∼20 s), precisely controllable process supports scalable 3D manufacturing of continuous fibers exceeding 10 m. Beyond mechanical robustness, the materials dynamically respond to force, humidity, and pH, mimicking biological tissues. As a proof of concept, the fibers function as artificial muscles and flexible capacitive sensors, highlighting their potential for advanced applications in biomaterials, bioengineering, and soft electronics.