Inspired by the structures of enzymes, a fast and robust strategy for generating ZIF-90 metallo-nanozyme is presented. The Zn-N coordination structure in the ZIF-90 can closely imitate the catalytic center...

Over the past several decades, the design and development of nanomaterials with intrinsic enzyme-mimicking activities (nanozymes) have attracted increasing attention. Herein, we present a simple strategy for the construction of graphene−gold nanoparticle (Graphene/Au-NPs) nanozymes via a one-step hydrothermal reaction, which can act as a highly efficient dye scavenger with the synergetic effect of adsorption and degradation. The asprepared nanocomposites can overcome the intrinsic drawbacks of singlecomponent Au-NPs, such as ease of aggregation and cannot capture substrates effectively. In our catalytic system, Graphene/Au-NPs can readily adsorb organic dyes onto their surfaces, catalyze H 2 O 2 to generate • OH radicals, and then exhibit outstanding removal performance toward different organic dyes. Their catalytic mechanism is analogous to that of natural enzymes, in which the specific high catalytic efficiency depends mainly on their capacity to keep the substrate close to the active site of the enzyme. Collectively, our work may pave the way to apply multifunctional nanozymes in different research areas, such as environmental treatment, sensing, and biotechnology.

Metal–organic frameworks (MOFs) have attracted significant research interest in biomimetic catalysis. However, the modulation of the activity of MOFs by precisely tuning the coordination of metal nodes is still a significant challenge. Inspired by metalloenzymes with well-defined coordination structures, a series of MOFs containing halogen-coordinated copper nodes (Cu-X MOFs, X = Cl, Br, I) are employed to elucidate their structure–activity relationship. Intriguingly, experimental and theoretical results strongly support that precisely tuning the coordination of halogen atoms directly regulates the enzyme-like activities of Cu-X MOFs by influencing the spatial configuration and electronic structure of the Cu active center. The optimal Cu–Cl MOF exhibits excellent superoxide dismutase-like activity with a specific activity one order of magnitude higher than the reported Cu-based nanozymes. More importantly, by performing enzyme-mimicking catalysis, the Cu–Cl MOF nanozyme can significantly scavenge reactive oxygen species and alleviate oxidative stress, thus effectively relieving ocular chemical burns. Mechanistically, the antioxidant and antiapoptotic properties of Cu–Cl MOF are achieved by regulating the NRF2 and JNK or P38 MAPK pathways. Our work provides a novel way to refine MOF nanozymes by directly engineering the coordination microenvironment and, more significantly, demonstrating their potential therapeutic effect in ophthalmic disease.

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The design and fabrication of biopolymer‐incorporated flexible electronics have attracted immense interest in healthcare systems, degradable implants, and electronic skin. However, the application of these soft bioelectronic devices is often hampered by their intrinsic drawbacks, such as poor stability, inferior scalability, and unsatisfactory durability. Herein, for the first time, using wool keratin (WK) as a structural biomaterial and natural mediator to fabricate soft bioelectronics is presented. Both theoretical and experimental studies reveal that the unique features of WK can endow carbon nanotubes (CNTs) with excellent water dispersibility, stability, and biocompatibility. Therefore, well‐dispersed and electroconductive bio‐inks can be prepared via a straightforward mixing process of WK and CNTs. The as‐obtained WK/CNTs inks can be directly exploited to design versatile and high‐performance bioelectronics, such as flexible circuits and electrocardiogram electrodes. More impressively, WK can also be a natural mediator to connect CNTs and polyacrylamide chains to fabricate a strain sensor with enhanced mechanical and electrical properties. With conformable and soft architectures, these WK‐derived sensing units can be further assembled into an integrated glove for real‐time gesture recognition and dexterous robot manipulations, suggesting the great potential of the WK/CNT composites for wearable artificial intelligence.