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Nowadays, X-rays are playing increasingly important roles in daily life and industrial manufacture, which calls for effective and mobile shielding materials. However, it seems to be a paradox to prepare shielding materials simultaneously achieving excellent X-ray attenuation properties and superior mechanical strength. Here, an advanced leather-based X-ray shielding material containing bismuth and iodine (BiINP-LM) is prepared, and the stable and well-dispersed loading of high-Z element components is enabled by favorable interactions between bismuth iodide and leather, i.e., coordination, hydrogen bonds, and electrostatic attractions. A piece of BiINP-LM with 1.00 mm thickness displays an excellent X-ray attenuation efficiency of more than 90% in the photon energy range below 50 keV and 65% at 83 keV, which averagely exceeds ∼3% than that of the 0.25 mm lead plate and ∼5% than that of the 0.65 mm commercial lead apron. Additionally, the coordination between bismuth and leather provides an enhanced tensile and tear strength of ∼10-fold and 3-fold compared with the lead apron. It is worth mentioning that BiINP-LM also displays extra high water-vapor permeability, which is ∼50-fold more than the lead apron. Overall, this work opens up a new prospect for preparing advanced X-ray shielding materials with both excellent X-ray attenuation and outstanding physiomechanical performances.

A high-shielding, low secondary radiation, lightweight, flexible, and wearable X-ray protection material was prepared by coimpregnating La 2 O 3 and Bi 2 O 3 nanoparticles in natural leather (NL) with an additional Bi 2 O 3 coating at the bottom surface of the leather. The prepared Bi 28.2 @Bi 3.48 La 3.48 −NL (28.2 and 3.48 mmol•cm −3 are the loading contents of elements) showed excellent X-ray shielding ability (65−100%) in a wide energy range of 20−120 keV with reduced scattered secondary radiation (30%). The bottom surface coating played a critical role in enhancing the X-ray attenuation and reducing the scattered secondary radiation by reflecting and deflecting incident X-ray photons. Excellent mechanical property with superb bending resistance of the NL matrix was properly maintained, and its tensile strength and tearing load were 15.39 MPa and 25.81 N•mm −1 , respectively. This lightweight and wearable high-performance protection material can facilitate safety and comfortability during intensive activities of practitioners in the health care industry.

Preventing X‐rays from reaching the human body is of great significance for the safe implementation of a wide range of related technologies. However, the current materials are commonly accompanied with low mechanical properties and backscatter radiation hazards. In this study, a structural material with high mass attenuation coefficients in a wide energy range (10–100 keV) is developed. The integration of high‐Z elements in hierarchical collagen nanofibers strongly reduces the backscatter radiation, resulting in only 28% of secondary radiation compared with a standard lead plate. The water vapor permeability of the engineered leather is nearly 340 times higher than commonly used synthetic and natural polymers. Compared with the commercial rubber‐based materials, the tensile strength of the engineered leather increased to 27.22 MPa (tenfold increase) and tear strength to 78.5 N mm−1 (threefold increase), respectively. A fully tailored engineered leather suit provides a 24.7% lower metabolic rate of locomotion and 67% reduced body heat compared with commercial lead aprons, which can facilitate better performance and safety during intensive activities in the health care and nuclear industries. This work lays a foundation for the engineering of next‐generation X‐ray shielding materials with potential large impact on the X‐ray application landscape.

Engineering advanced therapeutic and diagnostic nano‐bio‐platforms (NBPFs) have emerged as rapidly‐developed pathways against a wide range of challenges in antitumor, antipathogen, tissue regeneration, bioimaging, and biosensing applications. Emerged 2D materials have attracted extensive scientific interest as fundamental building blocks or nanostructures among material scientists, chemists, biologists, and doctors due to their advantageous physicochemical and biological properties. This timely review provides a comprehensive summary of creating advanced NBPFs via emerging 2D materials (2D‐NBPFs) with unique insights into the corresponding molecularly restructured microenvironments and biofunctionalities. First, it is focused on an up‐to‐date overview of the synthetic strategies for designing 2D‐NBPFs with a cross‐comparison of their advantages and disadvantages. After that, the recent key achievements are summarized in tuning the biofunctionalities of 2D‐NBPFs via molecularly programmed microenvironments, including physiological stability, biocompatibility, bio‐adhesiveness, specific binding to pathogens, broad‐spectrum pathogen inhibitors, stimuli‐responsive systems, and enzyme‐mimetics. Moreover, the representative therapeutic and diagnostic applications of 2D‐NBPFs are also discussed with detailed disclosure of their critical design principles and parameters. Finally, current challenges and future research directions are also discussed. Overall, this review will provide cutting‐edge and multidisciplinary guidance for accelerating future developments and therapeutic/diagnostic applications of 2D‐NBPFs.

The past few decades have witnessed the flourish of creating metal oxides for biocatalytic therapeutics due to their structural diversities, feasible modifications, tunable catalytic sites, and low cost when compared to their natural enzyme counterparts. Here, in this timely review, the most recent progress and future trends in engineering tunable structured metal oxides and decoding their structure‐reactivity relationships for biocatalytic therapeutics is comprehensively summarized. At first, the fundamental activities, evaluations, and mechanisms of metal oxide‐based biocatalysts are carefully disclosed. Subsequently, the merits, design methods, and state‐of‐art achievements of different types of nanostructured and biofunctionalized metal oxides are thoroughly discussed. Thereafter, it provides detailed comments on the catalytic center modulation strategies to engineer metal oxides for efficient reactive oxygen species (ROS)‐catalysis, including atomic catalytic site engineering, heterostructures, and support effects. Furthermore, the representative applications of these ROS‐catalytic metal oxides have been systematically summarized, such as catalytic disinfections, cancer therapies, ROS scavenging and anti‐inflammations, biocatalytic sensors, as well as corresponding toxicities. Finally, current challenges and future perspectives are also highlighted. It is believed that this review can provide cutting‐edge and multidisciplinary instruction for the future design of ROS‐catalytic metal oxides and stimulate their widespread utilization in broad therapeutic applications.

Exploring rapid, sensitive, and multifunctional biosensors is of great significance in medical diagnosis and biotechnology, while creating Cu‐N‐C center‐based enzymatic biodetection system is still a great challenge for colorimetric biosensing fields. Herein, inspired by the axial coordination structure of the natural enzyme, an efficient and specific Cu‐N‐C center‐based peroxidase‐like biocatalyst is created via axial strong‐metal‐support‐interaction (SMSI) between WOx support and Cu‐Nx‐based carbon shell, denoted as Cu‐NC‐WO3. This analysis discloses that the SMSI effect induces electron transfer from Cu to WOx, thus making the valence state of Cu higher and consequently suppressing the O intermediates' adsorption. Owing to this unique structure, the Cu‐NC‐WO3 exhibits exceptional peroxidase (POD) like activities (Km = 3.57 × 10−3 m, Vmax = 13.80 × 10−6 m s−1, and turnover number (TON) = 206.13 × 10−3 s−1 for H2O2), which is more efficient than the other Cu‐Nx center‐based biocatalysts and also many recently reported peroxidase‐like nanomaterials. Meanwhile, this Cu‐NC‐WO3 shows substrate selectivity, low detection limit, and high resistance to extreme environments for abundant H2O2‐related biomarkers, which are revealed by colorimetric studies. Thus, as a helpful method for accurate biodetection, it is believed this work promises to offer rapid, specific, and inexpensive colorimetric biosensors for regions with bare medical resources, as well as new strategies for the structural engineering of enzyme‐like biocatalysts.