The excessive accumulation of reactive oxygen species (ROS) under osteoporosis precipitates a microenvironment with high levels of oxidative stress (OS). This could significantly interfere with the bioactivity of conventional titanium implants, impeding their early osseointegration with bone. We have prepared a series of strontium (Sr)-doped titanium implants via micro-arc oxidation (MAO) to verify their efficacy and differences in osteoinduction capabilities under normal and osteoporotic (high OS levels) conditions. Apart from the chemical composition, all groups exhibited similar physicochemical properties (morphology, roughness, crystal structure, and wettability). Among the groups, the low Sr group (Sr25%) was more conducive to osteogenesis under normal conditions. In contrast, by increasing the catalase (CAT)/superoxide dismutase (SOD) activity and decreasing ROS levels, the high Sr-doped samples (Sr75% and Sr100%) were superior to Sr25% in inducing osteogenic differentiation of MC3T3-E1 cells and the M2 phenotype polarization of RAW264.7 cells, thus enhancing early osseointegration. Furthermore, the results of both in vitro cell co-culture and in vivo studies also showed that the high Sr-doped samples (especially Sr100%) had positive effects on osteoimmunomodulation under the OS microenvironment. Ultimately, the collated findings indicated that the high proportion Sr-doped MAO coatings were more favorable for osteoporosis patients in implant restorations.

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On‐chip microsupercapacitors (MSC) with facile fabrication procedures, high integration design, and superior performance are desired as an energy storage device for microelectronics. Hence, a novel procedure is proposed to fabricate an asymmetric microsupercapacitor (AMSC), employing interwoven nanowire (NW) network electrodes of poly(3,4‐ethylenedioxythiophene) coated titanium oxynitride (P‐TiON) and vanadium nitride (VN) NW as a cathode and an anode, respectively. The interwoven NWs with a high mass loading offer a sufficient electrochemical reaction area and rapid electron/ion transport pathway, delivering superior energy and power densities. With the LiCl/polyvinyl alcohol electrolyte, the assembled P‐TiON//VN AMSC can achieve a wide voltage window from 0 to 1.8 V with an excellent areal capacitance of 72 mF cm−2, a high areal energy density of 32.4 μWh cm−2 (at 0.9 mW cm−2), an outstanding power density of 45 mW cm−2 (at 21.9 μWh cm−2), and a good cycling performance. Furthermore, the substrate‐free electrodes exhibit outstanding integrability, and the system on one printed circuit board including two AMSCs in series and a LED demonstrates excellent practicability.

Although capsule-like materials as host carriers for enzyme encapsulation have been a hot topic in recent years, creating an ideal microenvironment for enhanced enzymatic performance is still a formidable challenge. Herein, we created a template-free method to in situ encapsulate natural enzymes in hollow covalent organic framework (COF) capsules at room temperature. The COF crystallites migrated from the inner core and self-assembled at the outside walls during the inside-out Ostwald ripening process, retaining the enzymes in the cavity. The adjustable hollow structure of the enzyme@COF capsule allowed the basic vibration of the enzyme to maintain a certain degree of freedom, thus significantly enhancing the enzymatic bioactivity. The hollow enzyme@COF capsule has large mesoporous tunnels allowing the efficient transport. In addition, the enzyme encapsulated in the capsule showed superior activity and ultrahigh stability under various extreme conditions that may lead to enzyme inactivation, such as high temperature, organic solvents, chelates, and the denaturing agent. Finally, the prepared hollow GOx@COF capsule was used for electrochemical sensing of glucose in human serum, and the electrochemical sensor exhibited high selectivity and satisfactory test results. This research not only provides a new way for COFs to encapsulate enzymes but also has potential applications in biocatalysis and biosensing, making artificial organelles possible.

In recent years, metal–organic frameworks (MOFs) have been extensively studied as candidate enzyme immobilization platforms. However, conventional MOF–enzyme composites usually exhibit low controllability and reusability. In this study, a novel and stable strategy for enzyme immobilization was designed by use of ZIF-8 to encapsulate in situ DNA–enzyme composites on the surface of magnetic particles (MPs). The mechanism of in situ encapsulation was discussed in detail. It was found that immobilized enzymes were involved in the growth of ZIF-8, and the DNA cross-linking agents promoted the growth of ZIF-8 on the surface of MP. The thermal, chemical, and physical stabilities of horseradish peroxidase (HRP) were all significantly enhanced after in situ encapsulation. Most importantly, this strategy was proven to be a general platform that can be used to stabilize various proteins. The in situ encapsulation strategy was expanded to immobilize a cascade of enzymes, and ZIF-8@MPGOx–HRP possessed high selectivity and a wide linear range (25–500 μM) for glucose detection.