Large Surface Research Articles

Redox Activity of Co Species in the Active Sites of CoNx/CoOx Facilitates Oxygen Electrocatalysis for Zn-Air Batteries.

Developing efficient bifunctional oxygen electrocatalysts is crucial for enhancing the performance of rechargeable Zn-air batteries (ZABs). In this study, cobalt/cobalt oxides embedded in N-doped carbon nanofibers (Co/CoOx/NCNFs) were synthesized through a combination of electrospinning and annealing processes. The resulting Co/CoOx/NCNFs catalysts feature abundant CoNx and CoOx active species, leveraging the large specific surface area of nanofibers to facilitate oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). The optimized Co/CoOx/NCNFs-0.1 achieved a half-wave potential (vs. RHE) of 0.82 V and required only 429 mV to reach 10 mA cm-2 in a typical three-electrode system with 0.1 M KOH using an electrochemical workstation equipped with a pine instruments rotator, outperforming the Pt/C+RuO2. The assembled ZABs exhibited high specific capacity (771 mAh gZn -1), substantial power density (981.6 mWh gZn -1), and long-term stability (>325 h). In situ Raman spectroscopy confirmed that the electrocatalytic processes involve the redox activity of Co (II and III) species derived from abundant CoNx and CoOx, elaborating the origin of the catalysts' exceptional oxygen electrocatalysis performance. This work not only presents a straightforward and effective approach for producing bifunctional oxygen electrocatalysts in ZABs but also sheds light on the catalytic mechanisms underlying ORR and OER for CoNx/CoOx-based oxygen electrocatalysts.

Bidirectional enhancement of output performance of nanogenerators by M-COFs materials

The emergence of nanogenerators, which have the ability to capture mechanical energy from the environment and to collect and transmit tiny energy, is rapidly becoming a hot research topic. The performance of electrode materials is the key to the efficiency of nanogenerators. Covalent organic skeletons (COFs), a class of crystalline organic porous materials with the advantages of large specific surface area, high porosity, tunable structure, and flexible tailorability, have very significant advantages in being used as nanogenerator materials. In this paper, we synthesised two COF materials to investigate the effect of the introduction of active metals on the friction power generation performance of COFs without changing their topology, COF-2 containing zinc ions is capable of generating a short-circuit current of 107.5 µA during friction. The porous structure increases the effective contact area to form a larger charge density, and the introduction of metal ions can accelerate the charge separation and transport. The two bidirectional synergistic effects of the materials significantly improve the output performance of the nanogenerator, and a simple and efficient method is explored for the enhancement of the output performance of COF-based triboelectric nanogenerators.

Synergistic Interaction of Strongly Polar Zinc Selenide and Highly Conductive Carbon Nanoframeworks Accelerates Redox Kinetics of Polysulfides.

Lithium-sulfur batteries (LSBs) have become strong competitors in secondary battery systems because of their superior theoretical capacity and energy density. However, due to the serious shuttle effect of soluble long-chain lithium polysulfides (LiPSs) and the slow solid-solid reaction kinetics, LSBs face some specific challenges, such as a short cycle life and low rate performance. The introduction of selenide/carbon composites derived from zeolite imidazolate frameworks (ZIFs) into separator coatings is a direct and effective solution to the aforementioned problems. Here, a zinc selenide/carbon catalyst material (ZnSe@C) was constructed and employed to modify commercial polypropylene (PP) separators to accelerate the conversion of intermediates. The highly polar ZnSe effectively fixes the active material on the cathode side by transferring electrons between elements with LiPSs and improves the utilization rate of sulfur. Concurrently, the highly conductive carbon nanoskeleton generated following the pyrolysis of ZIF-8 ensures the rapid transfer of charges during the catalytic reaction. The prepared ZnSe@C has a large specific surface area (250.07 m2 g-1) and mesoporous ratio (78.03%), which not only enhances adsorption and catalysis but also promotes the penetration of the electrolyte and the transport of Li+. Based on this, ZnSe@C/PP separator cells exhibit a low average capacity decay rate of 0.051% per cycle after 500 cycles at 1 C.

Hollow Magnetic Nanocarrier-Based Microrobot Swarms for NIR-Responsive Targeted Drug Delivery and Synergistic Therapy.

Nanocarriers are frequently used for drug delivery due to their large surface area, biocompatibility, and photothermal effects. However, they face the problem of premature drug leakage during drug transport. To address this challenge, we developed near-infrared light (NIR)-responsive hollow magnetic nanocarriers (HMC) by incorporating a chitosan-based molecular valve onto hollow magnetic nanocarriers (CHMC) to enable NIR-triggered drug release. Despite this advancement, this material still encounters the challenge of inadequate targeting. Recognizing the efficacy of magnetically driven micro/nanorobot swarms in remote wireless control, targeted motion, and efficient transport, we merged CHMC with magnetically controlled micro/nanorobot swarms. We evaluated their performance under programmable magnetic fields, which can be precisely controlled in biological fluid and directed toward targeting cells. Additionally, they demonstrated the ability to execute a responsive drug release under NIR irradiation. Ultimately, we confirmed their capacity for targeted delivery, responsive drug release, and photothermal therapy for liver cancer treatment in vivo. This approach heralds new possibilities for responsive drug therapy facilitated by micro/nanorobot swarms, offering promising advancements in medical treatment.

Research Progress on Using Nanoparticles to Enhance the Efficacy of Drug Therapy for Chronic Mountain Sickness

Chronic mountain sickness (CMS) poses a significant health risk to individuals who rapidly ascend to high altitudes, potentially endangering their lives. Nanoparticles (NPs) offer an effective means of transporting and delivering drugs, protecting nucleic acids from nuclease degradation, and mediating the expression of target genes in specific cells. These NPs are almost non-toxic and easy to prepare and store, possess a large surface area, exhibit good biocompatibility and degradability, and maintain good stability. They can be utilized in the treatment of CMS to enhance the therapeutic efficacy of drugs. This paper provides an overview of the impact of NPs on CMS, discussing their roles as nanocarriers and their potential in CMS treatment. It aims to present novel therapeutic strategies for the clinical management of CMS and summarizes the relevant pathways through which NPs contribute to plateau disease treatment, providing a theoretical foundation for future clinical research.

NiCoP nanoparticles distributed on N-doped carbon-nanosheets loading on nickel phosphide as self-supporting electrode for efficient overall water splitting

The investigation of a bifunctional self-supporting catalytic electrode holds significant practical importance for the application of overall water splitting. In this paper, a precursor with a large specific surface is constructed by growing ZIF-67 nanosheets on nickel foam. Subsequently, Ni–Co bimetallic phosphide particles (NiCoP) are obtained through phosphating, which distributed in N-doped carbon material and loaded on nickel phosphide (NiCoP@NC-Ni3P/NF), facilitating the overall water splitting. Due to its large specific surface area, the double electron regulation of Ni and Co, as well as the synergistic interaction between NiCoP and Ni3P, NiCoP@NC-Ni3P/NF exhibits excellent hydrogen/oxygen evolution properties, only requiring 125.6/288.4 mV to achieve 20 mA cm−2. Its performance of overall water splitting only requires an applied voltage of 1.54 V to reach 10 mA cm−2. Moreover, the NiCoP particles embedded in the nitrogen-doped carbon can effectively reduce electrolyte corrosion, ensuring exceptional catalyst stability.

Biochar Regulates the Humification of Kitchen Waste and the Effects of the Humic Acid Structure of Products on Black Soil

Kitchen waste is a misplaced resource that is characterized by a high organic matter content, high water content, and a tendency to rot easily. Biochar is a black solid substance produced under high-temperature, anaerobic conditions using agricultural organic wastes as the raw material. It possesses a large specific surface area, a loose and porous structure, and functional groups, which confer high thermal stability and strong adsorption capabilities. However, little is known about how humic products made from biochar affect the composition and structure of soil humus. To solve the above problems, this study carried out a two-year outdoor field experiment by means of element analysis, infrared spectroscopy, and differential thermal analysis (0.4 kg/m2 (W4), 0.8 kg/m2 (W8), 1.2 kg/m2 (W12), 1.6 kg/m2 (W16), and 2.0 kg/m2 (W20)); CK was the blank control (no application). The samples were collected one year and two years after they returned to the field. The results showed that the application of organic materials facilitated the accumulation of soil organic carbon (SOC) and increased the total nitrogen (TN) content. The highest SOC content in the W20 treatment was 12.39 g/kg and 14.67 g/kg in one and two years, respectively. The maximum relative HA content in the W20 treatment was 22.99% one year after returning to the field. The PQ value (the ratio of HA/(fulvic acid (FA) + HA)) for the W20 treatment was 88.21%. The W20 treatment greatly increased the SOC and humus carbon contents. Compared with the CK treatment, all the organic materials applied for one year improved the structure of the humic acid to varying degrees, increased the degree of oxidation, reduced the degree of condensation and thermal stability of the HA in the soil, and gradually simplified the structure of the humic acid; among all the treatments, the W20 treatment had the greatest effect.

Ni-TiO2-g-C3N4 nanosorbent for oxytetracycline antibiotic decontamination

ABSTRACT The release of antibiotics in the water and wastewater has created harm due to impending effects on the environment and thus their elimination, is of vital importance. Therefore, this work endeavours to eradicate the oxytetracycline (OT) antibiotic utilising a facile ultrasonic assisted sol-gel synthesised Ni-TiO2-g-C3N4 (NiTCN) composite as an adsorbent. Using various techniques, the prepared samples revealed the development of the target nanostructure as indicated by the X-ray diffraction (XRD) patterns, where the crystallite size of ≈ 50 nm and the characteristic functional groups of the composite were confirmed by the Fourier-transform infrared spectroscopy (FTIR) analysis. On the other hand, the elemental composition was verified by energy-dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). The g-C3N4, TiO2, and NiO estimated percentages from the EDS data were 32.7%, 66.4%, and 0.9%, respectively. The large surface area enabled to efficiently eliminate the OT antibiotic. The OT adsorption fitted the Langmuir adsorption model concentration of 5–100 mg/l, 25 ml volume of OT, and 10 mg NiTCN at room temperature with a q max value of 266 mg/g, pseudo-second-order kinetics, and intraparticle and film adsorption contributions. Electrostatic attractions, surface complexation, π-π interactions, and hydrogen bonding were postulated as the modes of the OT anchoring to the adsorbent’s surface. The effect of ions such as Cl−, CO3 2−, Na+, and Mg2+ ions, which are usually present in water systems, on the OT adsorption was studied. The study findings shed light on the possible usage of the prepared nanocomposite to remove antibiotic pollutants‎.

Metal–Organic Frameworks for Electrocatalytic CO2 Reduction: From Catalytic Site Design to Microenvironment Modulation

AbstractThe electrochemical reduction of CO2 to high‐value carbon‐based chemicals provides a sustainable approach to achieving an artificial carbon cycle. In the decade, metal–organic frameworks (MOFs), a kind of porous crystalline porous materials featuring well‐defined structures, large surface area, high porosity, diverse components, easy tailorability, and controllable morphology, have attracted considerable research attention, serving as electrocatalysts to drive CO2 reduction. In this review, the reaction mechanisms of electrochemical CO2 reduction and the structure/component advantages of MOFs meeting the requirements of electrocatalysts for CO2 reduction are analyzed. After that, the representative progress for the precise fabrication of MOF‐based electrocatalysts for CO2 reduction, focusing on catalytic site design and microenvironment modulation, are systemically summarized. Furthermore, the emerging applications and promising research for more practical scenarios related to electrochemical CO2 conversion are specifically proposed. Finally, the remaining challenges and future outlook of MOFs for electrochemical CO2 reduction are further discussed.

An innovative strategy for Gefitinib quantification in pharmaceutical and plasma samples using a graphene quantum dots-combined gold nanoparticles composite electrochemical sensor.

Aninnovative methodology is proposedfor quantifying Gefitinib(GFT) using an electrochemical sensor constructed from a composite of graphene quantum dots (GQDs) and gold nanoparticles (AuNPs). GQDs were synthesized from graphite, preserving graphene's large surface area and excellent electron transfer capabilities while enhancing dispersibility. The combination of GQDs with AuNPs resulted in an AuNPs@GQDs composite, which was used to construct the sensor. The synthesized nanomaterials were characterized using scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and the electrochemical performance of the sensor was evaluated via cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Under optimized conditions, the sensor displayed a linear calibration curve for GFT detection within the range 0.01 to 10.0 µM, with a limit of detection (LOD) of 0.005 µM (S/N = 3). The sensor demonstrated excellent anti-interference properties and stability in tests using pharmaceutical formulations and plasma samples. Compared to chromatographic methods, the sensor exhibited similaraccuracy and recovery. Its easy fabrication and high sensitivity make it a promising tool for pharmaceutical analysis and clinical therapeutic drug monitoring.

Diagnosis and Biomarker Screening of Endometrial Cancer Enabled by a Versatile Exosome Metabolic Fingerprint Platform.

Exosomes have emerged as a revolutionary tool for liquid biopsy (LB), as they carry specific cargo from cells. Profiling the metabolites of exosomes is crucial for cancer diagnosis and biomarker discovery. Herein, we propose a versatile platform for exosomal metabolite assay of endometrial cancer (EC). The platform is based on a nanostructured composite material comprising gold nanoparticle-coated magnetic COF with aptamer modification (Fe3O4@COF@Au-Apt). The unique design and novel synthesis strategy of Fe3O4@COF@Au-Apt provide the material with a large specific surface area, enabling the efficient and specific isolation of exosomes. The exosomes captured Fe3O4@COF@Au-Apt can be directly used as the laser desorption/ionization mass spectrometry (LDI-MS) matrix for rapid exosomal metabolic patterns. By integrating these functionalities into a single platform, the analytical process is simplified, eliminating the need for additional elution steps and minimizing potential sample loss, resulting in large-scale exosomal metabolic fingerprints. Combining with machine learning algorithms on the metabolic patterns, accurate discrimination between endometrial patients (EGs) and benign controls (CGs) was achieved, and the area under the receiver operating characteristic curve of the blind test cohort was 0.924. Confusion matrix analysis of important metabolic fingerprint features further demonstrates the high accuracy of the proposed approach toward EC diagnosis, with an overall accuracy of 94.1%. Moreover, four metabolites, namely, hydroxychalcone, l-acetylcarnitine, elaidic acid, and glutathione, have been identified as potential biomarkers of EC. These results highlight the great value of the integrated exosome metabolic fingerprint platform in facilitating low-cost and high-throughput characterization of exosomal metabolites for cancer diagnosis and biomarker discovery.

Implantable Microarray Patch: Engineering at the Nano and Macro Scale for Sustained Therapeutic Release via Synthetic Biodegradable Polymers

AbstractTransdermal drug delivery has been an increasingly studied alternative drug administration route owing to the large surface area of the skin, enabling ease of access and application. Among the various transdermal drug delivery technologies that have been developed so far, microarray patches (MAPs) incorporating microneedle technology (MN) have garnered much attention. MAPs can easily penetrate the stratum corneum, facilitating the delivery of desired substances directly into the skin, exhibiting a higher delivery efficiency compared to alternative transdermal drug delivery approaches. The effectiveness of MAPs in delivering therapeutics is affected by a multitude of factors, one of which is the selection of materials employed in their fabrication. Among various materials that have been used to fabricate MAPs, synthetic biodegradable polymers such as poly(lactic‐co‐glycolic acid) (PLGA) and polylactic acid (PLA) have been exploited for sustained and controlled release with excellent biocompatibility. PLGA and PLA can be used to construct the entire needle shaft or drug‐loaded microparticles which are then incorporated into needle layer. The combination of MN technology in conjunction with biodegradable polymers has revolutionized sustained and controlled transdermal delivery of small and large molecules.

Efficient fluoride recovery from wastewater using mesoporous Ca-based nanomaterials derived from municipal solid waste incineration fly ash via fluidized bed crystallization

This study introduces an innovative approach utilizing mesoporous Ca-based nanomaterial (MCN) derived from municipal solid waste incineration (MSWI) fly ash as carriers in a fluidized bed crystallization (FBC) process for the recovery of fluoride from semiconductor wastewater. The transformation of nonporous MSWI fly ash into mesoporous structures was achieved through facile treatments, including ultrasonic-assisted leaching with ethylenediaminetetraacetic acid disodium salt dihydrate (EDTA–Na) and surface modification with sodium silicate, enhancing surface functionalities and active site formation. The resulting MCN exhibited a significant surface area of 222.0 m2/g, ideal for fluoride recovery. When tested with synthetic wastewater, the recovery efficiency and crystallization ratio of fluoride using MCN in the FBC system reached 99.0 % and 93.3 %, respectively. Further investigation revealed that the unique surface properties and large surface area of the MCN promoted the crystallization of fluoride-containing precipitates, resulting in homogeneously nucleated cubic CaF2 crystals and facilitating layer-by-layer crystal growth. Testing the FBC process with real semiconductor wastewater resulted in a crystallization efficiency of 94.5 %, with the CaF2 content in the recovered precipitates reaching 84.3±0.7 %. These findings highlight the potential of MCN as an innovative carrier for fluoride recovery, demonstrating a novel and environmentally friendly method for converting waste into valuable materials. This study offers a promising solution for treating fluoride-contaminated wastewater, with high potential to revolutionize industrial wastewater management and promote a circular economy.

A Review on Green Synthesized Metal Nanoparticles Applications

Nanotechnology pertains to the manipulation of materials at exceedingly small scales, specifically between 1 and 100 nanometers. Materials at this scale exhibit significantly different properties compared to the same materials at larger scales. An emerging trend is the utilization of nanoparticles (NPs) to address environmental issues. Metallic nanoparticles are among the several nanoparticles that are extensively utilized in environmentally sustainable endeavors. A sustainable, economical, and enduring approach is to synthesize nanoparticles through a more ecologically friendly procedure instead of a physical or chemical method. Plant components primarily function as reducing and capping agents in eco-friendly synthesis. Diverse metallic nanoparticles of various sizes and shapes have been created utilizing extracts from plant materials, including leaves, bark, fruits, and flowers. The synthesis of Nobel laureate metal nanoparticles is essential to the medical sector. A diverse array of glycosides and phenolic compounds constitutes numerous organic constituents in plants, facilitating the synthesis of metal nanoparticles. The absence of detrimental by-products in metal nanoparticle synthesis is the primary significance of green synthesis. The nanoparticles generated by an eco-friendly approach demonstrate several significant biological activity. A substantial body of literature demonstrates that the synthesized nanoparticles are efficacious against both gram-positive and gram-negative bacteria, including E. coli, Bacillus subtilis, Klebsiella pneumoniae, and Pseudomonas fluorescens. The synthesized nanoparticles not only display antifungal efficacy against several cancer cell lines, including those of breast cancer, but also demonstrate antifungal activity against Trichophyton simii, Trichophyton mentagrophytes, and Trichophyton rubrum. Moreover, they exhibit potent antioxidant properties. The dimensions and morphology of these metal nanoparticles substantially influence their functionalities. Particles characterized by a large surface area and diminutive size provide significant potential for medical applications. This paper aims to provide a comprehensive summary of current advancements in the synthesis of nanoparticles utilizing biological entities and their numerous potential applications.

Achieving High Stability and Capacity in Micron-Sized Conversion-Type Iron Fluoride Li-Metal Batteries.

Iron fluoride, a conversion-type cathode material with high energy density and low-cost iron, holds promise for Li-ion batteries but faces challenges in synthesis, conductivity, and cycling stability. This study addresses these issues by synthesizing micron-sized iron-fluoride using a simple solid-state synthesis. Despite a large particle size, a high capacity of 571mAhg-1 is achieved, which is attributed to the unique surface and internal pores within the iron-fluoride particles, which provided a large surface area. This is the first study to demonstrate the feasibility of using large iron fluoride particles to enhance the energy density of the electrode and achieve an iron fluoride full cell with high capacity. Also, the cause of the capacity fading is investigated. Electrode delamination from the current collector, which is the main cause of capacity fading in early cycles, is resolved using a carbon-coated aluminum (C/Al) current collector. Moreover,iron (Fe) dissolution and the deposition of dissolved Fe on the Li metal also contributed significantly to the degradation. Localized high-concentration electrolytes (LHCEs)suppress iron dissolution and Li dendrite growth, resulting in long-cycle stability for 300 cycles. This study provides insights into the further development of conversion-type metal fluorides across various compositions.

Magnetic particles–integrated microfluidics: from physical mechanisms to biological applications

Abstract Magnetic nanoparticles (MNPs) have garnered significant attention in biomedical applications. Due to their large surface area and tunable properties, MNPs are used in microfluidic systems, which allow for the manipulation and control of fluids at micro- or nanoscale. Using microfluidic systems allows for a faster, less expensive, and more efficient approach to applications like bioanalysis. MNPs in microfluidics can precisely identify and detect bioanalytes on a single chip by controlling analytes in conjunction with magnetic particles (MPs) and separating various particles for analytical functions at the micro- and nanoscales. Numerous uses for these instruments, including cell-based research, proteomics, and diagnostics, have been reported. The successful reduction in the size of analytical assays and the creation of compact LOC platforms have been made possible with the assistance of microfluidics. Microfluidics is a highly effective method for manipulating fluids as a continuous flow or discrete droplets. Since the implementation of the LOC technology, various microfluidic methods have been developed to improve the efficiency and precision of sorting, separating, or isolating cells or microparticles from their original samples. These techniques aim to surpass traditional laboratory procedures. This review focuses on the recent progress in utilizing microfluidic systems that incorporate MNPs for biological applications.

Adsorption and evolution of N2 molecules over ZnO monolayer: a combined DFT and kinetic Monte-Carlo insight

AbstractA large surface area, wide band gap, and unique bonding property between Zn and O atoms make the hexagonal ZnO monolayer attractive as a gas sensor. In the present work, the adsorption and evolution of nitrogen (N2) molecules over a ZnO monolayer have been studied using two different theoretical methods: van der Waals density functional theory (vdW-DFT) and kinetic Monte-Carlo (kMC) simulation. The adsorption and diffusion (hopping over the surface) energy of a N2 gas molecule has been calculated considering the different sites over the ZnO substrate using the revPBE-vdW functional. Bader charge, electron localization function analysis, density of states and band structure plotting have been used to understand the adsorption mechanism. Lateral repulsive interaction between two N2 molecules limits the maximum packing number of gas molecules within one hexagonal ring. The output of the vdW-DFT calculation has been fed to the kMC code to predict the rate of adsorption, desorption, and diffusion, along with the overall surface coverage at different temperatures and pressures. Finally, the change in the N2 adsorption energy has been predicted with the increase of the ZnO layer number.

Graphene aerogel with double pore structure for marine oil spill emergency response

Due to its high porosity, large specific surface area, and strong photothermal conversion performance, graphene aerogel has unique advantages in the field of pollution treatment, especially in the field of recovering highly viscous oils. However, for the treatment of highly viscous oils, the high adsorption capacity and high adsorption rate of graphene aerogel often cannot be combined, which is one of the important reasons limiting its development in this field. A double-step templating strategy for graphene aerogels preparation was used in this work, i.e., Pickering emulsion soft templating and unidirectional freeze casting. Specifically, the dense Pickering emulsion droplets can be stabilized in a short period of time, so that they can be cured quickly. After that, graphene aerogels (DGA-0.8-25) with dual pore structure were prepared by unidirectional freeze casting technology to further form aligned pores based on the pores formed by the Pickering emulsion droplet soft template. The dense presence of Pickering emulsion droplets gives DGA-0.8-25 an ultra-high porosity (96.8 %), which can adsorb 184.53 times its own mass of crude oil. Due to the unidirectional pore structure, the adsorption rate of DGA-0.8-25 on crude oil is as high as 8.39 g·g−1·min−1, which realizes dual improvement of the adsorption capacity and rate of graphene aerogel on crude oil and shows a good application prospect in the treatment of high viscosity crude oil. In addition, DGA-0.8-25 has unique advantages in the field of oil–water separation, with a separation efficiency of 99.04 % for water-in-oil emulsions and 97.63 % for oil-in-water emulsions. When repeated used in photothermal adsorption of highly viscous oil, DGA-0.8-25 can still maintain more than 90.61 % of its initial adsorption capacity after ten cycles of use-regeneration. Because of its unique advantages such as high efficiency and low cost, DGA shows promising in its future large-scale use.

2D Fe/Co-MOF/SOX cascade reactors for fast noninvasive detection of sarcosine level in prostate cancer urine

Sarcosine plays a key role in screening for early prostate cancer. However, the several already reported peroxidase mimics immobilized with sarcosine oxidase (SOX) utilized to detect uriary sarcosine still have some limitations such as complex synthesis process, using of expensive heavy metals to mimic enzyme activity and long color development time. Herein, an inexpensive peroxidase-like 2D Fe/Co-MOF nanosheet was prepared by a simple solvent modulation method. The resultant 2D Fe/Co-MOF nanosheets have strong peroxidase activity, with its Vmax value for H2O2 of 15.3 × 10-8 M/s, being 1.76 times that of HRP. Then, using the 2D Fe/Co-MOF as a peroxidase model for anchoring natural SOX to construct 2D Fe/Co-MOF/SOX , which can act as a cascade reactor for detection of sarcosine. Considering the above properties, a platform for the detection of sarcosine was built based on a colorimetric method. Because of presence of the high ratio of Fe2+ caused by the electron transfer from Co2+ to Fe3+, large specific surface area and plentiful active sites, 2D Fe/Co-MOF/SOX with TMB (3,3′,5,5′-tetramethylbenzidine) colorimetric reagent could have fast color development and can be applied conveniently and fastly in an early screening tool for prostate cancer patients. The sarcosine could be quantified by peroxidase activity with a detection range of 1–400 μM and a limit of detection (LOD) of 0.324 μM. More importantly, the average sarcosine concentration of 21.367 μM and 1.871 μM was detected in patient’s and normal urine (n = 5), respectively, which showed an excellent screening effect and a great potential in early prostate cancer.

A Programmable Handheld Extrusion-Based Bioprinting Platform for In Situ Skin Wounds Dressing: Balance Mobility and Customizability.

Bioprinting technology plays a crucial role for constructing tissue substitutes. However, the mismatched scaffold shapes and the poor treatment timeliness limit its clinical translational application. In situ printing technology that prints bioregenerants directly inside patient's body can meet the needs of specific tissue repair. This study develops a smartphone controlled handheld bioprinter for in situ skin wounds dressing. The mini bioprinter can be handheld and placed on any printing surface to create strips, complex patterns, and 3D structures, and can be equipped with microchannel needles to expand functionality. The size of the strips as well as the printing path can be programmed and controlled by the smartphone to ensure the precision of the printed product quality. Furthermore, the device not only allows for smooth switching between different bioinks for printing heterogeneous structure, but also allows for fast and uniform coverage of large wound surfaces. When dealing with complex wounds in vitro & vivo, the printer can effectively fill and precisely close wounds, promoting wound healing. The programmable handheld bioprinter can balance mobility and customizability in the management of skin wounds and is expected to realize its potential for emergency medical treatment in condition-constrained scenarios, such as battlefields or disaster areas.