Structures, properties, and challenges of emerging 2D materials in bioelectronics and biosensors

Bioelectronics are powerful tools for monitoring and stimulating biological and biochemical processes, with applications ranging from neural interface simulation to biosensing. The increasing demand for bioelectronics has greatly promoted the development of new nanomaterials as detection platforms. Recently, owing to their ultrathin structures and excellent physicochemical properties, emerging two‐dimensional (2D) materials have become one of the most researched areas in the fields of bioelectronics and biosensors. In this timely review, the physicochemical structures of the most representative emerging 2D materials and the design of their nanostructures for engineering high‐performance bioelectronic and biosensing devices are presented. We focus on the structural optimization of emerging 2D material‐based composites to achieve better regulation for enhancing the performance of bioelectronics. Subsequently, the recent developments of emerging 2D materials in bioelectronics, such as neural interface simulation, biomolecular/biomarker detection, and skin sensors are discussed thoroughly. Finally, we provide conclusive views on the current challenges and future perspectives on utilizing emerging 2D materials and their composites for bioelectronics and biosensors. This review will offer important guidance in designing and applying emerging 2D materials in bioelectronics, thus further promoting their prospects in a wide biomedical field.

Bioinspired Spiky Peroxidase-Mimics for Localized Bacterial Capture and Synergistic Catalytic Sterilization.

Besides the pandemic caused by the coronavirus outbreak, many other pathogenic microbes also pose a devastating threat to human health, for instance, pathogenic bacteria. Due to the lack of broad-spectrum antibiotics, it is urgent to develop nonantibiotic strategies to fight bacteria. Herein, inspired by the localized "capture and killing" action of bacteriophages, a virus-like peroxidase-mimic (V-POD-M) is synthesized for efficient bacterial capture (mesoporous spiky structures) and synergistic catalytic sterilization (metal-organic-framework-derived catalytic core). Experimental and theoretical calculations show that the active compound, MoO3 , can serve as a peroxo-complex-intermediate to reduce the free energy for catalyzing H2 O2 , which mainly benefits the generation of •OH radicals. The unique virus-like spikes endow the V-POD-M with fast bacterial capture and killing abilities (nearly 100% at 16 µg mL-1 ). Furthermore, the in vivo experiments show that V-POD-M possesses similar disinfection treatment and wound skin recovery efficiencies to vancomycin. It is suggested that this inexpensive, durable, and highly reactive oxygen species (ROS) catalytic active V-POD-M provides a promising broad-spectrum therapy for nonantibiotic disinfection.

Transition Metal and Metal-Nx Codoped MOF-Derived Fenton-Like Catalysts: A Comparative Study on Single Atoms and Nanoparticles.

To deal with the ever-growing toxic benzene-derived compounds in the water system, extensive efforts have been dedicated for catalytic degradation of pollutants. However, the activities and efficiencies of the transition metal-based nanoparticles or single-atom sites are still ambiguous in Fenton-like reactions. Herein, to compare the Fenton-like catalytic efficiencies of the nanoparticles and single atoms, the free-standing nanofibrous catalyst comprising Co nanocrystals and Co-Nx codoped carbon nanotubes (CNTs) or bare Co-Nx doped CNTs is fabricated. It is noteworthy that all these nanofibrous catalysts exhibit efficient activities, mesoporous structures, and conductive carbon networks, which allow a feasible validation of the catalytic effects. Benefiting from the maximized atomic utilization, the atomic Co-Nx centers exhibit much higher reaction kinetic constant (κ = 0.157 min-1 ) and mass activity toward the degradation of bisphenol A, far exceeding the Co nanocrystals (κ = 0.082 min-1 ). However, for the volume activities, the single-atom catalyst does not show apparent advantages compared to the nanocrystal-based catalyst. Overall, this work not only provides a viable pathway for comparing Fenton-like catalytic effects of transition metal-based nanoparticles or single atoms but also opens up a new avenue for developing prominent catalysts for organic pollutants' degradation.