A Protein-Managed Hydrogel Biomimicked by Insect Cuticle Enabling Ultra-Durable Impact Resistance

The insect cuticle exhibits a diverse array of intricate microstructures, each possessing distinctly different mechanical properties, ranging from rigid components such as head capsules and mandibles to softer structures like larval integuments and intersegmental membranes. While the variations in mechanical properties are attributed to differences in structural protein composition, the specific proteins involved and their corresponding mechanisms remain largely elusive. Here, Ostrinia furnacalis cuticular protein hypothetical-2 (Of CPH-2) is identified as a highly abundant key structural protein that is closely linked to the development of the endocuticle within the head capsule of Ostrinia furnacalis. Utilizing a straightforward yet effective binary solvent-induced strategy involving chitin and OfCPH-2, the hierarchically structured endocuticle is successfully replicated. Rational engineering of the lamellar structure formation and energy dissipation, surprisingly and reasonably facilitated by OfCPH-2, contributes synergistically to an unprecedented ultra-durable impact resistance (≈23,534 J·m^-2, ≈1,032 × increase). This structure parallels that of the natural lamellar endocuticle found in head capsules, enabling exceptional structural stability under localized mechanical stresses. Applying this biomimetic cuticle in intelligent agricultural drones has significantly enhanced their sustainability, easy-to-process, and stability (≈600% × increase) within visual recognition systems for pests, underscoring its promising potential as protective gear akin to natural cuticles.