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• Norepinephrine impart Pd aerogel with good biocompatibility for in vivo anti-bacteria. • The POD-like and OD-like activity of NE-Pd aerogels could eliminate the biofilm. • The GPX-like activity of NE-Pd aerogels deplete GSH to amplify the ROS generation. • Induced hyperthermia enhances intrinsic multienzyme-like activity of NE-Pd aerogels. Nanozymes have become promising alternatives to antibiotics for fighting bacteria owing to their broad-spectrum antibacterial activity, robust stability, and multifunctionality. However, the deficient activity of nanozymes and the overexpressed glutathione in the infectious microenvironments extensively hamper their antibacterial efficiency. Herein, we present a norepinephrine (NE) induced Pd metallic aerogel as a highly efficient hydrophilic nanozyme for photothermal-enhanced chemodynamic therapy for bacterial infections and wound healing. The prepared NE-Pd aerogels exhibit satisfactory peroxidase-like and oxidase-like activity, which could generate an amount of hydroxyl radical and superoxide anion radical to cause irreversible damage to bacteria and decompose biofilm components with no bacteria resistance. In addition, the glutathione peroxidase-like activity of NE-Pd aerogels could deplete glutathione to adjust the infectious microenvironments for intensifying the generation of ROS, thus boosting the chemodynamic therapeutic efficacy. Furthermore, the intrinsic photothermal effect of NE-Pd aerogels generates hyperthermia to impair bacteria and further substantially promotes the multienzyme-like activity to damage bacteria and their biofilms. Consequently, the animal skin-wound model results further denoted that NE-Pd aerogels could effectively cure methicillin-resistant Staphylococcus aureus (MRSA) infected wounds with excellent in vivo biocompatibility in either wound tissue or living organisms. This work demonstrates that NE-Pd aerogel nanozymes have tremendous potential as a synergistically photothermal-catalytic antibacterial agent for treating bacterial infection and accelerating wound healing. [ABSTRACT FROM AUTHOR]

[Display omitted] • Metal clusters were used to form local electric fields on carbon foam. • An interface-local electric field can improve the electronic structure of metals. • This enhanced adsorption/desorption performance in ORR and OER. • The optimized electrocatalyst demonstrated outstanding performance for ZABs. Practical application of rechargeable zinc-air batteries is restricted by slow oxygen reaction kinetics of their bifunctional catalysts. This study is based on the ability of interface-localized electric fields to enhance charge transfer and accelerate electrochemical reactions. Fe and VN metal clusters formed on the foam carbon were used to form local electric field-orientated heterogeneous interfaces, which exhibited effective adsorption and catalytic performance for ORR/OER. Theoretical simulations and ultraviolet photoelectron spectroscopy analysis have confirmed that an interface electric field close to the Fermi level can improve the electronic structure of metals, enhancing their adsorption/desorption performance in ORR and OER. The resulting Fe ACs -VN NCs (1:1) /NFC material exhibited "coupling-conversion" effect and demonstrated outstanding bifunctional ORR/OER activity (E 1/2 = 0.87 V, E j=10 = 1.476 V). The rechargeable zinc-air battery, assembled using the newly prepared catalyst, displayed a high specific capacity of 779 mAh g−1 and was stable after 3104 operation cycles. The study substantiates the possibility of ion diffusion and charge transfer acceleration by interface-localized electric fields induced in zinc-air battery electrodes. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A novel PEC strategy was developed for sensitive detection of dual microRNAs. • Mo 2 C nanotubes were successfully employed as nanocarriers. • The strategy was based on the energy transfer between CQDs and AuNPs. • The low detection limits of 0.15 fM and 0.21 fM were achieved. • It is the first time that a CQD-based ET biosensor was designed for PEC detection. Abstract Herein, a novel photoelectrochemical (PEC) biosensor was developed for the ultrasensitive detection of dual microRNAs (miRNAs), with the detection being based on energy transfer (ET) between carbon quantum dots (CQDs) and gold nanoparticles (AuNPs). The PEC platform consisted of a CQDs@Mo 2 C nanotube modified ITO electrode. Two hairpin probes (H1 and H2) carrying the Au NPs were used "switch off" and "switch on" the PEC signal of the CQDs, with a close approach of the tagged AuNPs to the CQDs quenching the PEC signal. The introduction of different miRNAs (miRNA-159b and miRNA-166a) altered the interparticle distance between the AuNPs and CQDs, thereby affecting the intensity of the PEC response. This approach allowed the highly sensitive detection of both miRNA-159b and miRNA-166a. The linear range of the biosensor for miRNA-159b and miRNA-166a detection were 0.5–5000 fM, with low detection limits of 0.15 fM and 0.21 fM, respectively. To our knowledge, this is the first reported CQDs-based ET biosensor for the PEC detection of dual miRNAs. Results suggest that this approach offers a promising platform for the ultrasensitive detection of multiple miRNAs. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel and facile strategy was designed to fabricate COF capsules. • It can exhibit excellent analytical performance for the SARS-CoV-2 RNA detection. • The detection limits of 0.28 pM was achieved. • The proposed method has been used to analyze the clinical samples. The ongoing outbreak of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has highlighted that new diagnosis technologies are crucial for controlling the spread of the disease. Especially in the resources-limit region, conveniently operated detection methods such as "naked-eye" detection are urgently required that no instrument is needed. Herein, we have designed a novel and facile strategy to fabricate covalent organic framework (COF) capsules, which can be utilized to establish a new colorimetric assay for naked-eye detection of SARS-CoV-2 RNA. Specifically, we employ the digestible ZIF-90 as the sacrificial template to prepare the hollow COF capsules for horseradish peroxidase (HRP) encapsulation. The fabricated COF capsules can provide an appropriate microenvironment for the enzyme molecules, which may improve the conformational freedom of enzymes, enhance the mass transfer, and endow the enzyme with high environmental resistance. With such design, the proposed assay exhibits outstanding analytical performance for the detection of SARS-CoV-2 RNA in the linear range from 5 pM to 50 nM with a detection limit of 0.28 pM which can go parallel to qTR-PCR analysis. Our method also possesses excellent selectivity and reproducibility. Moreover, this method can also be served to analyze the clinical samples, and can successfully differentiate COVID-19 patients from healthy people, suggesting the promising potential in clinical diagnosis. [ABSTRACT FROM AUTHOR]

[Display omitted] • SARS-CoV-2 PLpro as a new biomarker is used to diagnose COVID-19. • A novel PLpro-activated peptide-DNA smart nanoprobe is designed for sensitive and specific detection of SARS-CoV-2. • The fabricated biosensor can be used for the detection of SARS-CoV-2 in blood, saliva, and clinical samples. • The biosensor can be used to screen and validate inhibitors of SARS-CoV-2 PLpro. The persistent coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is still infecting hundreds of thousands of people every day. Enriching the kits for SARS-CoV-2 detection and developing the drugs for patient treatments are still urgently needed for combating the spreading virus, especially after the emergence of various mutants. Herein, an electrochemical biosensor has been fabricated in this work for the detection of SARS-CoV-2 via its papain-like cysteine protease (PLpro) and the screening of protease inhibitor against SARS-CoV-2 by using our designed chimeric peptide-DNA (pDNA) nanoprobes. Utilizing this biosensor, the sensitive and specific detection of SARS-CoV-2 PLpro can be conducted in complex real environments including blood and saliva. Five positive and five negative patient throat swab samples have also been tested to verify the practical application capability of the biosensor. Moreover, we have obtained a detection limit of 27.18 fM and a linear detection range from 1 pg mL−1 to 10 μg mL−1 (I = 1.63 + 4.44 lgC). Meanwhile, rapid inhibitor screening against SARS-CoV-2 PLpro can be also obtained. Therefore, this electrochemical biosensor has the great potential for COVID-19 combating and drug development. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydroquinone-mediated OPECT biosensing strategy was developed. • ZnSe/Bi 2 MoO 6 heterojunction was employed as photoactive material. • Sensitive and selective detection of FTO protein was achieved. • Hemin catalyzed the oxidation of ZnSe and hydroquinone by H 2 O 2 was employed to achieve signal suppression. • Rhein and perfluorohexane sulfonate inhibited FTO protein activity. Organic photoelectrochemical transistor (OPECT) biosensing is a new concept that combines photoelectrochemical and organic electrochemical transistor biosensing. It reduces background noise and combines both signal amplification for low abundance biomolecule detection. In this work, an OPECT biosensor for the detection of fat mass and obesity-associated protein (FTO) was constructed, in which ZnSe/Bi 2 MoO 6 was chosen as the gate material, hm6ARNA (containing N6-methyladenine RNA sequence) as the target molecule, and hydroquinone as the electron donor. Under FTO oxidation induced RNA demethylation, the formation of hemin loaded with G-quadruplex on the electrode surface was triggered. With the catalysis of hemin-based DNAzyme towards the oxidation reaction caused by H 2 O 2 towards hydroquinone and ZnSe, the electron donor was consumed and ZnSe was oxidized in situ to form SeO 2 which reduced the photo-anodic response. The variation of the gate effectively gated the state of the channel polymer thus producing different channel current responses, a process that was closely related to the content of FTO. In addition, the effects of rhein and potassium perfluorohexanesulfonate on FTO activity were also investigated in this experiment, with IC 50 values of 10.62 μM, 31.28 mg/L respectively. [ABSTRACT FROM AUTHOR]

Rational design of molecular phototheranostic platform for NIR-II fluorescence Imaging-guided Chemodynamic-Photothermal combined therapy. Herein, a NIR-II fluorescence imaging-guided organic small molecular phototheranostic platform (IR-FE-Fc@DSPE-S-S-PEG) was designed via a convenient strategy, which can act not only as a PTT agent to produce a thermal effect of killing cancer cells under near-infrared laser (808 nm) irradiation but also as a CDT agent converts the endogenously less reactive H 2 O 2 into the harmful •OH and simultaneously with the depletion of GSH to achieve an amplified CDT. This work proposes a novel strategy for PTT-CDT combined efficacy treatment via a rational design of a disintegrable NIR-II fluorescence imaging-guided organic molecular phototheranostic platform. [Display omitted] • A newly NIR-II organic small molecular probe was established for real-time tumor location detection and visualization of the therapeutic process. • 4-Arm functional ferrocenes linkage enhances the loading of CDT reactants, and organic composition makes good biocompatibility. • The multiple synergistic strategies under the conditions of high-loading Fe2+, GSH depletion, and photothermal effect improved the Fenton reaction efficiency. • The enhanced CDT-PTT therapy reversed immunosuppression and stimulated the immune system in a mouse model. The strategy of synergetic chemodynamic treatment (CDT) and photothermal therapy (PTT) to improve the anticancer effect has been a hot spot in the field of biomedicine. Herein, a high-performance near-infrared II (NIR-II) fluorescence imaging-guided molecular phototheranostic platform (IR-FE-Fc@DSPE-S-S-PEG) was designed via a convenient strategy. IR-FE-Fc@DSPE-S-S-PEG can serve as a PTT agent to kill cancer cells under near-infrared laser (808 nm) irradiation and a CDT agent to convert the endogenously less reactive H 2 O 2 into the harmful •OH, simultaneously deplete the glutathione (GSH) to achieve an amplified CDT as well. Notably, PTT-induced hyperthermia can further enhance the CDT effect, achieving a synergistic PTT/CDT therapy. Due to the enhanced permeability and retention (EPR) effect and the high GSH microenvironment of the tumor, IR-FE-Fc@DSPE-S-S-PEG exhibited much higher tumor accumulation revealed by NIR-II fluorescence imaging. More importantly, IR-FE-Fc@DSPE-S-S-PEG efficiently damages tumorous tissues without inducing side effects to normal tissues under 808 nm laser irradiation. This work has proposed an alternative PTT-CDT combined therapy platform based on a rational design of disintegrable NIR-II fluorescence imaging-guided molecular for effective tumor treatment. [ABSTRACT FROM AUTHOR]

Precise adjustment of the electronic structure of conductive MOFs load materials plays an important role in the design of electrocatalysts. In this paper, a hydrogen evolution catalyst in the full pH range was prepared by using a rapid microwave method to partially carbonize conductive MOFs materials and quickly anchoring small metal Ru nanoparticles on them. [Display omitted] • Ru@p-Co 3 HHTP 2 is quickly prepared by a microwave solid-phase pyrolysis method. • Partial carbonization and SMSI in microwave improves stability and reactivity. • This catalyst has excellent hydrogen evolution performance in the full pH range. • DFT calculations and experiments revealed the synergy between Ru and p-Co 3 HHTP 2. Conductive metal organic frameworks (MOFs) have limited their long-term development in the actual electrocatalytic test process due to their low activity and poor stability. Here, for the first time, ultra-small Ru nanoparticles supported by a novel conductive MOF material (Co 3 HHTP 2) were synthesized simply and quickly (60 s) using only a household microwave oven. In this process, the conductive MOF is partially carbonized, strong metal carrier interaction (SMSI) is generated, and Ru nanoparticles are firmly attached to the carrier to form Ru@p-Co 3 HHTP 2. The Ru@p-Co 3 HHTP 2 -3.2% catalyst has excellent hydrogen evolution performance in the full pH range. Density functional theory calculations (DFT) result shows that the partial carbonization of the conductive MOF and the presence of SMSI promote the charge transfer at the interface between Ru nanoparticles and Co 3 HHTP 2 , which not only synergistically accelerates the water dissociation step and reduces the hydrogen adsorption energy, but also enhances the stability of the catalyst. [ABSTRACT FROM AUTHOR]

• A novel sensor array for different pathogens identification is proposed. • The platform based on diverse interactions between 2D-MOFs and peptides. • Various pathogens can be detected and discriminated in urine. • The procedure of this sensor array is very simple and fast with only ~15 min. Rapid and efficient identification of pathogen is indispensable in clinical diagnosis because of the extremely severe consequence induced by pathogens infection. Taking advantages of the various compositions of pathogen surfaces, in this work we have proposed a simple and rapid sensor array for different pathogens identification and discrimination based on two-dimensional metal–organic frameworks (2D-MOFs) conjugated with functional peptide. Owing to the outstanding physical and chemical properties, ultrathin 2D-MOFs can adsorb dye-labeled peptides and consequently quench the fluorescence quickly and efficiently. Nevertheless, in the presence of pathogens, the anionic surface and different bimolecular composition of pathogens will endow them to interact with the 2D-MOFs or peptides through the diverse non-specific interactions. Subsequently, the dye-labeled peptides can be released with a recovery of fluorescence intensity. Consequently, the sensor array can identify various pathogens rapidly and efficiently based on the distinct fluorescence response patterns. Moreover, experimental results reveal that this approach can discriminate different pathogens with 100% accuracy, even in urine or mixed samples, demonstrating its reliability and effectiveness in the complex biological samples. More importantly, the procedure of pathogens identification by using this sensor array is very fast with only ~ 15 min, indicating the great potential applications in the timely clinical treatments and reliable monitoring of infectious disease trends. [ABSTRACT FROM AUTHOR]