Self-catalyzed nitrogen-doped carbon nanotubes connected FeCo nanostructures for electrochemical sensitive detection of metol

Metol is a photographic developer that is extremely toxic to aquatic organisms due to its widespread use and improper handling in aquatic environments. Therefore, it is urgent to develop reliable strategies for its detection. Herein, we have designed an efficacious, expeditious and dependable electrochemical sensors for electrochemical determination of metol based on a self-catalyzed nitrogen-doped carbon nanotubes connected FeCo nanostructures (denoted FeCo@NC). The FeCo@NC formed from MOF-on-MOF hybrids of FeCo-MOF@ZIF-8. The porous structure formed by ZIF-8 after pyrolysis enhances diffusion kinetics, while the large number of carbon nanotubes produced by ZIF-8 has a beneficial impact on the field of electrocatalysis. The large electrically active surface area, rapid electron transfer rate and high electrocatalytic capacity exhibited by FeCo@NC were utilized to construct a highly sensitive sensor for the determination of metol. The limit of detection was found to be 0.024 μM, with a linear range of 0.08-450 μM. Furthermore, the developed sensor demonstrated excellent catalytic activity for the detection of metol, along with stability, reproducibility and selectivity. The sensor was employed for the analysis of water samples, yielding promising recovery results.

Incorporating nickel-substituted polyoxometalate into a photoactive metal-organic framework for efficient photodegradation of thiamethoxam insecticide

Hydrogen bonding enhances the interactions between host and guest molecules and facilitates electron transfer between them. In this study, a series of hydrogen-bonded Z-scheme photocatalysts were prepared via impregnation. Nickel (Ni)-substituted polyoxometalate (POM) Na6K4[Ni4(H2O)2(PW9O34)2]∙32H2O (Ni4P2) was anchored within the pores of Zr6(μ3-OH)8(-OH)8(TBAPy)2 (NU-1000) via hydrogen bonding interactions (H4TBAPy = 1,3,6,8-tetrakis(p-benzoic acid)pyrene). Hydrogen bonding not only effectively prevented the leakage of Ni4P2 from NU-1000 pores but also facilitated electron transfer from Ni4P2 to NU-1000. The optimized 0.3-Ni4P2@NU-1000 photocatalyst delivered remarkable performance toward thiamethoxam (TMX) photodegradation, achieving a degradation efficiency of 75.1 % after 120 min. The effects of the photocatalyst dose, pH, coexisting ions, and water sample on TMX degradation were investigated. Radical scavenging experiments and electron spin resonance data revealed that superoxide radicals and holes are the primary species responsible for photodegradation. Moreover, the reaction mechanism and degradation pathways of TMX were thoroughly investigated. Density functional theory calculations confirmed that TMX is adsorbed onto Ni4P2 via hydrogen bonding, structurally changing TMX and increasing its susceptibility to degradation. Chia seed growth experiments and Toxicity Estimation Software Tool analysis indicated that the aquatic toxicities of TMX intermediates and final products are lower than that of the undegraded TMX. This study advances the application of substituted POM-modified NU-1000 for treating TMX-contaminated wastewater.

Balancing performance and stability characteristics in organic electrochemical transistor

Nowadays organic electrochemical transistors (OECTs) are becoming a promising platform for bioelectronics and biosensing due to its biocompatibility, high sensitivity and selectivity, low driving voltages, high transconductance and flexibility. However, the existing problems associated with degradation processes within the OECT during long-term operation hinder their widespread implementation. Moreover, trade-offs often arise between OECT transconductance and speed, fast ion transport and electron mobility, electrochemical stability and sensitivity, cycling stability and signal amplification, and other metrics. Ensuring high performance characteristics and achieving enhanced stability in OECTs are distinct strategies that do not always align, as progress in one aspect often necessitates a trade-off with the other. This dynamic arises from the need to find a balance between reversible and irreversible processes in the behavior of OECT active layers, and providing simultaneously favorable conditions for ion and electron transport and their efficient charge coupling. This review article systematically summarizes the phenomenological and physical-chemical aspects associated with factors and mechanisms that determine both performance and long-term stability of OECT, paying special attention to the consideration of existing and promising approaches to extend the OECT lifespan, while maintaining (or even increasing) high effectiveness of its operation.

Advancements in small molecule fluorescent probes for the detection of formaldehyde in environmental and food samples: A comprehensive review

Formaldehyde (FA), a hazardous substance with carcinogenicity and mutagenicity, necessitates sensitive and accurate detection methods for protecting public health and the environment. While numerous reviews have explored FA fluorescent probes, the current literature predominantly emphasizes biological systems, leaving a gap in addressing FA's roles in environmental monitoring and food safety. This review discusses recognition mechanisms for FA detection, including 2-aza-Cope rearrangement, methylenehydrazine reaction, formimine formation, and other mechanisms. Furthermore, this review underscores the practical applications of these probes in real-world contexts, namely their incorporation into test strips, hydrogels, and membranes for environmental monitoring and food safety. Moreover, this review highlights future directions for developing intelligent detection systems that combine fluorescent probes with data processing algorithms and artificial intelligence technologies. By synthesizing the current knowledge in this area, this review aims to stimulate future research and advancements in FA detection technology, ultimately contributing to improved environmental management and public health protection.

A smartphone-assisted 2D Cd-MOF-based mixed-matrix membrane exhibiting visual and on-site quantitative sensing of antibiotics and pesticides for food safety

Food contamination is a current global concern, thus rapid and accurate quantitative detection of contaminants is essential for ensuring food safety. Herein, a MOF-based mixed-matrix membrane (1@PMMA) was fabricated by incorporating a stable 2D luminescent Cd-MOF, {[Cd2(L)2(DMSO)2]·2DMSO}n (1) (H2L = 5-(4-(pyridin-4-yl)benzamido)benzene-1,3-dioic acid), into a flexible poly(methyl methacrylate) (PMMA) matrix. The resulting 1@PMMA exhibited sensitive, strong anti-interference, recyclable, and visual detection of nitrofurazone (NFZ) and 2,6-dichloro-4-nitroaniline (DCN). Furthermore, a portable smartphone-assisted sensing platform was developed by coupling the luminescent 1@PMMA with a smartphone, to realize visual and on-site quantitative detection of NFZ and DCN in real food samples. This work provides a portable and intelligent sensing platform for the visual and on-site quantitative detection of antibiotic and pesticide residues in food samples, demonstrating significant potential for food safety monitoring and quality control.

Ultrasensitive point-of-care testing of salmonella in lettuce and milk samples using a recombinase polymerase amplification-based colorimetric/fluorescent dual-readout lateral flow assay

A portable dual-mode RPA-based LFA sensor was developed for Salmonella detection in lettuce and milk samples. The fimY gene of Salmonella was chosen as specific conserved sequences, their corresponding primers based on RPA conditions were designed and optimized, and respectively labeled with Biotin and FAM groups at 5' end, then applied for efficient fimY gene fragments enrichment via RPA. Sandwich construction of streptavidin-RPA products-AuNPs@FAM antibody was generated on T-line, showing positive results within 10 min, colorimetric-fluorescent signals were captured by a smartphone and converted into gray intensities and fluorescence intensities, further enabling the quantification of Salmonella with detection limits of 10 cfu/mL and 1 cfu/mL for colorimetric and fluorescent modes, respectively, over a linear range of 101-106 cfu/mL. The proposed strategy provided a valuable reference for Salmonella one-site detection, which would be utilized as a universal method for other food-borne pathogens detection by matching specific conserved sequences and primer designs.

Effects of phosphate, sodium, and potassium ions on the transacylation reaction between propylene glycol alginate and sodium caseinate

The transacylation reaction between sodium caseinate (NaCas) and propylene glycol alginate (PGA) forms covalent conjugates with improved functionalities, but the effects of ions are unknown. The objective of this study was to evaluate the effect of phosphate, sodium, and potassium ions on the degree of glycation (DOG) after reaction at pH 11.0 and 21 °C for 2 h. The highest DOG at 1:1 (w:w) NaCas/PGA as measured with the ortho-phthalaldehyde assay was observed at 10 mM salt, following the order of KH2PO4 > KCl > NaH2PO4 = NaCl, while DOG was similar at ≥25 mM salt. The stronger binding of sodium than potassium ions with NaCas led to the lower DOG based on measuring conductivity and 23Na nuclear magnetic resonance. The reaction improved the solubility of NaCas at pH 4.5. The findings can be used to increase the yield of covalent casein-alginate conjugates and thus casein functionalities.

Rapid and sensitive detection of foodborne pathogens via nanoparticle-assisted ICP-MS and electrochemical multimodal analysis

Foodborne pathogens-induced diseases are a major global public health concern. We have developed a novel sandwich hybridization technique that integrates magnetic separation with noble metal nanoparticle labeling, enabling the rapid, highly specific, and sensitive detection of Salmonella typhimurium, Vibrio parahaemolyticus, and Shigella sonnei, simultaneously. This technique involves forming sandwich-structure complexes by hybridizing pathogen DNA with corresponding report probe-grafted noble metal nanoparticles and capture probe-grafted magnetic nanoparticles (MNPs). These complexes are magnetically separated and analyzed using inductively coupled plasma mass spectrometry (ICP-MS), where the noble metal content correlates with the pathogen DNA concentration. Furthermore, changes in conductivity are monitored through electrochemical differential pulse voltammetry, enhancing detection reliability. The dual-sensing approach allows precise quantification of multiple pathogens simultaneously, with a wide detection range of 101 to 1010 copies·mL-1 and a low detection limit of 1 copy·mL-1. Successful application in real samples underscores its potential for ensuring food safety.

Revealing the oxidation mechanism of Antarctic krill oil induced by metal ion: Focusing on the influence of reverse micelles

Water-soluble copper (CuSO4), oil-soluble copper and different amount of water were added to demetallized and dehydrated Antarctic krill oil (AKO) for accelerated storage. The results showed that water-soluble copper (100 μmol/kg oil) could not significantly promote the oxidation of dehydrated AKO. While water-soluble copper (100 μmol/kg oil) exhibited stronger prooxidative property than oil-soluble copper (100 μmol/kg oil) in AKOs adding water. Meantime, with prolonged storage time of AKO adding water, the size of reverse micelle increased, the electronegativity and surface tension of the oil-water interface decreased, and adding water-soluble copper ions aggravated the above changes. Therefore, it was speculated that Cu2+ is adsorbed to the oil-water interface by the action of electric charge to promote the oxidation of phospholipids containing unsaturated fatty acids (UFAs) and free UFAs present at the interface by initiating the free radical chain reaction, thereby accelerating the oxidation of AKO.

Capturing and converting CO2 using amino acids as various commercially valuable nano-carbonates

Carbon dioxide (CO2) is the most significant greenhouse gas and one of the strategies to reduce CO2 emission is to convert CO2 into commercially valuable products. Currently, methods that can effectively capture and convert CO2 into carbonate nanomaterials, which have unique applications in various fields, have rarely been reported, and there are no universal methods that can capture and convert CO2 into different nano-carbonates. In this study, an innovative two-step strategy based on amino acids was developed to produce multiple different carbonate nanoparticles, including CaCO3, BaCO3, and Ag2CO3 nanoparticles with diameters of 70 nm, 50 nm, and 7 nm, respectively. Fundamentally important, the nuclear magnetic resonance data clearly demonstrated that it was the amino acids (e.g., glycine) that dictated the formation of carbonate nanoparticles. In the presence of amino acids, a competition in forming nanoparticles and microparticles was observed, and the formation of nanoparticles was proportional to the carbamate formed from CO2 reacting with amino acids. In the absence of amino acids, carbonate microparticles (~ 2 μm) were formed.

Synergistic effect of RuNi alloy supported by carbon nanohorns for boosted hydrogen evolution from ammonia borane hydrolysis

The present study addresses the critical challenges associated with hydrogen production from ammonia borane (AB) hydrolysis, focusing on the development of cost-effective, high efficient, and stable catalysts. A promising strategy to achieve superior catalytic performance in AB hydrolysis involves alloying noble and non-precious metals. Herein, RuNi bimetallic nanoparticles were successfully deposited onto carbon nanohorns (CNHs) through a facial hydrothermal-reduction processes. The optimized Ru0.6Ni0.4-CNHs catalyst demonstrates a remarkably high turnover frequency (TOF) of 144  [Formula: see text]  molRu-1 min-1, approximately twice that of Ru-CNHs. The synergistic effect between CNHs and the RuNi alloy enhances the anchoring and dispersion of metal particles, leading to reduced particle size and a narrow distribution, along with exceptional stability. Experimental results reveal that the incorporation of the RuNi alloy enables precise regulation of the electron distribution in Ru. Furthermore, density functional theory (DFT) calculations demonstrate that the RuNi alloy significantly reduces the activation and dissociation energies of AB and H2O on the Ru site of Ru0.6Ni0.4 compared to those on a monometallic Ru site. This work provides valuable insights for designing efficient and economical bimetallic nanocatalysts for AB hydrolysis.

In-situ injectable hydrogel for near-infrared-regulated hyperthermic perfusion therapy of triple-negative breast cancer

Hyperthermic perfusion therapy (HPT) is an emerging and effective treatment for intracavitary tumors, involving circulating a heated solution directly into body cavities such as the peritoneal or pleural spaces, targeting tumors more effectively while minimizing systemic toxicity. However, the clinical application of HPT is currently restricted to intracavitary tumors, and its efficacy is hampered by the up-regulation of thermal stress resistance genes, which enhance the thermal tolerance of cancer cells. Herein, we developed a temperature-sensitive methyl cellulose hydrogel with injectability and removability to enable targeted HPT for the triple-negative breast cancer (TNBC). Using bioinformatics screening, we identified 17-allylamino-17-demethoxygeldanamycin as a potent inhibitor and incorporated it alongside biocompatible cuttlefish ink-derived nanoparticles (CINPs), a natural photothermal agent, into the temperature-sensitive hydrogel. Under near-infrared (NIR) irradiation, CINPs mediate photothermal tumor ablation, while 17-allylamino-17-demethoxygeldanamycin reduces tumor cell resistance to hyperthermia. Moreover, the temperature-responsive phase transition of the hydrogel allows for its complete removal post-treatment, extending the scope of HPT beyond intracavitary tumors and minimizing inflammation at the injection site. This material-engineered HPT approach, achieved remarkable outcomes in both orthotopic and metastatic tumor models, inhibiting breast cancer progression and lung metastasis. These findings highlight the potential of materials-based HPT as an effective treatment for TNBC.

Bifunctional thiourea-based additives for synergistic enhancement of perovskite crystallization and defect density optimization

Hybrid perovskite solar cells (PSCs) have emerged as a promising alternative to crystalline silicon solar cells, owing to their excellent photovoltaic characteristics and straightforward fabrication processes. However, the rapid crystallization dynamics frequently results in unfavorable film morphology, giving rise to a plethora of defect sites and fostering the formation of trapped non-radiative recombination centers, thus limiting the further advancement and refinement of PSC technology. In this study, we introduce N-benzoylthiourea (N-BzTu) molecules as a passivate agent within PSCs through anti-solvent additive approach. The incorporation of CO and CS functional groups in N-BzTu effectively passivates the under-coordinated Pb2+ defects, while the formation of robust hydrogen bonding interactions between NH or NH2 groups and I- ions acts as a potent inhibitor against the generation of iodine vacancy defects. This dual-action mechanism not only addresses the issue of defect proliferation but also enhances the overall structural integrity of the PSC film. Moreover, by meticulously adjusting the growth rate of the perovskite crystals, we can achieve dense and uniformly distributed perovskite films. Specifically, the power conversion efficiency (PCE) of the optimized devices soared from 22.11 % to an impressive 24.05 %. Consequently, the hydrothermal stability of the device is also improved, with the initial efficiency of the unencapsulated device remaining above 80 % after 1540 h at 20-25 % relative humidity.

In-situ SERS monitoring of photocatalytic reduction on the surface of large-sized gold nanoparticles solely driven by organic semiconductor

The combination of in-situ SERS monitoring and photocatalysis could track reaction process, and deepen understanding of underlying mechanism of photocatalysis. The study of photocatalytic behavior driven by organic semiconductor is not as clear as plasmonic and inorganic semiconductor photocatalysis. Herein, an organic semiconductor hybrids reactor was constructed by decorating gold nanoparticles (Au NPs). The hybrids achieved in-situ SERS monitoring of photocatalytic degradation of rhodamine 6G with considerable sensitivity and uniformity. This has been attributed to the photocatalytic performance of organic semiconductor and the SERS effect of uniformly modified Au NPs. In particular, the hybrids monitored the photocatalytic reduction of 4-nitrobenzenethiol on its surface by in-situ SERS tracking the formation of intermediate product 4, 4'-dimercaptoazobenzene and end product 4-aminothiophenol. This work introduced organic semiconductor into photocatalysis and in-situ SERS monitoring field for enhancing understanding of the photocatalytic mechanism on organic surface, and developing the application potential of SERS technology.

Hierarchical NiGa-LDH/Ti3C2Tx MXene composites for enhanced capacitance in alkaline all-solid-state energy storage

In recent years, the rapid advancement of safe energy storage devices with high energy and power densities has generated significant interest in all-solid-state supercapacitors (SCs). MXene-based nanomaterials have emerged as promising candidates for energy storage owing to their exceptional redox properties, extensive surface area, and high metallic conductivity. Additionally, layered double hydroxides (LDHs), distinguished by their distinct nanostructures, and efficient ion channels, with elevated specific capacitance, have attracted interest. Consequently, a novel all-solid-state supercapacitor(AASCs) was fabricated by employing a hydrothermal method to integrate NiGa-LDH nanosheets with Ti3C2Tx MXene, resulting in enhanced energy storage properties. The NiGa-LDH/Ti3C2Tx MXene exhibits excellent properties, including a specific capacitance of 618.66 F g-1 at 1 mA cm-2 and 93.75 % capacitance retention after 5,000 cycles at 1 mA cm-2. The all-solid-state NiGa-LDH/Ti3C2Tx MXene//activated carbon(AC) asymmetric supercapacitor (AASCs) demonstrates an impressive energy density of 20 Wh kg-1 and a high power density of 400 W kg-1. Density-functional theory (DFT) studies show that NiGa-LDH/Ti3C2Tx MXene has a high density of states (DOS) around the Fermi level and possesses a potassium ion adsorption energy of -2.36 eV. This study provides technical and theoretical insights into the design of intricate nanostructures utilizing MXene-based nanomaterials for all-solid-state energy storage device.

Effect of hydrophilic polymers on the formation of size-controllable aqueous droplets in water-in-oil emulsion and the fabrication of porous micro-silica particles therefrom

Size-controllable droplets were formed in a water in oil (W/O) emulsion using only hydrophilic polymers without a surfactant to fabricate porous micro-silica particles larger than 20 μm. Droplets of various size ranging from 1 to 30 μm were prepared by emulsifying aqueous solutions containing four types of polymers, namely polyethylene glycol (PEG), polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), and polypropylene glycol (PPG), in a pentanol oil phase. Following the addition of tetraethyl orthosilicate (TEOS) as a silica precursor, silica particles were grown via hydrolysis and condensation reactions. The silica particle size depends on the degree of hydrophilicity of the polymers, which determines the interfacial tension between the water droplets and oil. Micro-silica particles >20 μm were obtained from PEG-based emulsion droplets. Notably, the distribution and stability of silica particles can be optimized by controlling the molecular weight and concentration of the hydrophilic polymer. A porous silica structure was successfully obtained by decomposing the residual polymer via an appropriate calcination process. The most uniform and stable porous micro-silica particles with an average size of 20 μm were obtained from an emulsion containing 5 wt% PEG (molecular weight: 4000) after calcination at 500 °C. This novel process enables the eco-friendly synthesis of porous micro-silica particles using only hydrophilic polymer without a surfactant and control of pore size and particle size of >20 μm.

Dual-mode thermochromic afterglow in phosphorus-doped carbon dot composites for visible light-activated information encryption

The phenomena of thermochromic afterglow have attracted significant attention in advanced information encryption and anticounterfeiting applications. However, it is still a challenge to realize visible light-activated thermochromic afterglow in a single material. Herein, we demonstrate thermochromic afterglow under visible light excitation in a novel carbon dot (CD)-based composite, utilizing a temperature-dependent dual-mode afterglow mechanism. The composite (PCD@BA) is synthesized by incorporating phosphorus-doped CDs (PCDs) into an inorganic rigid matrix via covalent bonding. Notably, phosphorus doping significantly enhances the photoluminescent properties and redshifts the excitation wavelength of the PCD@BA composite, enabling it to exhibit bright thermally activated delayed fluorescence (TADF) when activated by white light. The thermochromic afterglow of the PCD@BA composite exhibits dynamic color transitions from deep blue to orange by tuning the proportion of the temperature-dependent room temperature phosphorescence (RTP) and TADF. Consequently, the concepts of white light-excited high-resolution multilevel afterglow 2D code information encryption and thermochromic afterglow based anticounterfeiting labels were developed. This work offers exciting opportunities for utilizing CD-based materials with visible light-activated thermochromic afterglow in advanced information security fields.

Highly-sensitive and logic platform based on spatially-constrained T7 transcription enhanced Cas13a for DNA repair enzyme detection and intracellular imaging

The activity of DNA repair enzymes, particularly Flap endonuclease 1 (FEN1) and apurinic/apyrimidinic endonuclease 1 (APE1), plays a critical role in disease prevention, diagnosis, and prognosis. Accurate detection of these enzymes is therefore essential. Recent advancements in CRISPR-Cas technology, particularly its programmable and trans-cleavage activity, have paved the way for the development of innovative detection methods. However, there is a need for a simple, low-background, highly sensitive detection platform with logical capabilities for FEN1 and APE1. In this study, we present a novel detection platform that integrates spatially constrained T7 transcription with the CRISPR-Cas13a system. This biosensor minimizes background interference and achieves high sensitivity, with limits of detection as low as 5 × 10-7 U/μL for FEN1 and 2 × 10-8 U/μL for APE1, making it one of the most sensitive methods available for detecting these enzymes. The platform supports both OR and logic detection, offering enhanced versatility. It demonstrates robustness by detecting FEN1 activity at concentrations as low as 1 cell/μL and screening enzyme inhibitors. Additionally, the system was successfully used for intracellular imaging of FEN1 activity in cells and reliably measured APE1 activity in ovarian tissue samples, confirming its clinical applicability. This biosensor represents a promising tool for detecting FEN1 and APE1, further expanding the potential of CRISPR-Cas13a in diagnostic applications.

Nature of oxygen vacancy in accelerating redox kinetics of V2+/V3+ in flow batteries

The rational design of oxygen vacancy in metal oxide based catalysts is an effective strategy to enhance their intrinsic activity by influencing the microelectronic structure. However, the impact of oxygen vacancy on the reaction kinetics and the catalytic mechanism in vanadium redox flow batteries (VRFBs) remains under-explored. Herein, a novel approach is developed to regulate the concentration of oxygen vacancy in TiO2 nanoplates for high performance VRFBs. The oxygen vacancy-rich TiO2 efficiently facilitates the desorption and electron transfer process of V3+ during the electrochemical oxidation process. Owing to the enhanced electrochemical oxidation of V2+ to V3+, the inherently sluggish reaction kinetics of V2+/V3+ is significantly accelerated. The battery assembled with oxygen vacancy-rich TiO2 achieves an energy efficiency of 79.81 % at 200 mA cm-2 and outstanding long-term durability. This work not only elucidates the nature of oxygen vacancy in accelerating the redox kinetics of V2+/V3+ but also offers insights for rationally designing efficient catalysts for VRFBs.

Engineering oxide speciation in CoMnOx catalysts for achieving an ideal selective oxidation of benzyl alcohol at room temperature with atmospheric pressure air

In this work, based on unique dual-component cobalt-manganese oxide catalysts (CoMnOx) fabricated by a solid phase mixed foaming method, we demonstrate an embodiment of the ideal selective oxidation process simultaneously featured by low-cost catalysts, highly efficient utilization of air as oxidant at room temperature, impeccable balancing of high activity and perfect selectivity, high durability, super-facile unit operation at room temperature and atmospheric pressure. Based on their significantly higher catalytic activity than other reported non-noble metal catalysts, in the selective oxidation of benzyl alcohol (BzOH) with atmospheric pressure air as oxidant, CoMnOx catalysts exhibit remarkable activity at room temperature. A 23 % BzOH conversion with 100 % benzaldehyde (BzO) selectivity has been achieved at room temperature and atmospheric pressure while a 100 % BzOH conversion with 100 % BzO selectivity can be achieved at 55 °C. According to the structural characterizations, it was found that the MnCo2O4-Co3O4 oxide pairs characterized by rich Co3+/Co2+ and Mn3+/Mn2+ redox pairs can be formed in CoMnOx catalysts, and then highly effectively utilize the molecular oxygen in air to produce O2- radical, which initializes a highly efficient three-step radical-driven selective oxidation process of BzOH to produce BzO. An impeccable balancing of high activity and perfect selectivity has been achieved in this CoMnOx-air catalytic system. This room temperature and atmospheric pressure CoMnOx-air system provides a potential approaching to lucrative industrial oxidation processes, and also raises the expectation of new full spectrum oxidation catalysts based on transition metal oxides.

Defect and doping synergistic optimization for efficient and durable alkaline seawater hydrogen production

Seawater electrolysis offers a dual benefit of alleviating freshwater scarcity and advancing hydrogen energy technologies. However, its practical implementation is hindered by the complex chemical composition of seawater, particularly the corrosive chloride ions that induce electrode degradation and parasitic chlorine evolution, posing critical challenges to long-term electrolytic stability. To address this issue, we designed an efficient electrocatalyst by introducing vanadium (V) doping and oxygen vacancies (Ov) into nanoflower-structured Co3O4 (V-Co3O4(Ov)-250) through hydrothermal synthesis and controlled annealing. The Ov configuration modulates electronic structures and facilitates charge transfer, whereas V doping enhances corrosion resistance, increases lattice defects, and generates active sites. This dual modification synergistically improves surface reactivity and conductivity, boosting catalytic performance. V-Co3O4(Ov)-250 achieves low overpotentials of 69 mV for the hydrogen evolution reaction (HER) and 158 mV for the oxygen evolution reaction (OER) in alkaline freshwater, and 133 mV (HER) and 228 mV (OER) in alkaline seawater at a current density of 10 mA cm-2. When assembled into an electrolytic cell, the catalyst requires a low voltage of 1.68 V to drive a current density of 100 mA cm-2 in an alkaline seawater electrolyzer, while maintaining outstanding stability over 100 h of continuous operation. This performance surpasses that of most non-precious metal-based electrocatalysts for seawater electrolysis. Theoretical analysis elucidates that V doping promotes preferential adsorption of OH- at the active site and optimizes intermediates' adsorption-desorption equilibrium through its synergy with Ov, consequently lowering the reaction energy barrier and enhancing intrinsic catalytic activity.

Co-doping and N defect synergistically boosting 2e- oxygen reduction reaction on carbon nitride for full-day degradation of nitenpyram

Photocatalytic technology has garnered significant attention owing to its mild reaction conditions, broad applicability and lack of secondary pollution. However, its practical implementation in complex environments is significantly hindered by the stringent illumination requirements. Herein, a full-day photocatalysis-self-Fenton system was constructed by C, K co-doping and N defect jointly regulated graphitic carbon nitride (KCN-C). The experimental results demonstrate that the synthesized KCN-C not only enhances the efficiency of charge carrier separation, but also improves oxygen adsorption capacity and selectivity for the two-electron oxygen reduction reaction (2e- ORR). As a result, the KCN-C manifested remarkable photocatalytic hydrogen peroxide (H2O2) production efficiency, achieving a generation rate of 108.32 mM h-1 g-1 under illumination, which represents a 142.53-fold enhancement compared to pristine carbon nitride (CN). Notably, when nitenpyram (NTP) functions as an electron donor, the KCN-C demonstrates superior H2O2 production activity (3.52 mM h-1 g-1) while achieving a remarkable NTP degradation efficiency of 90 %. Moreover, the generated H2O2 can be subsequently activated to mineralize residual NTP and its intermediate products under dark conditions. This work provides novel insights into the rational design of full-day photocatalysis-self-Fenton systems for the efficient degradation of various refractory pollutants.

Breaking the conventional: Ligand-triggered Zn-MOF nanozyme with unusual oxidase activity for dual-channel sensing of benfuracarb

The activity of MOF-based nanozyme mainly relies on the metal sites, the development of organic ligands with intrinsic enzymatic-activity is of great significance for nanozyme-mediated sensors but it remains a huge challenge. Herein, the oxidase-like activity of an azo ligand, 4,4'-azodipyridine (AZPY), was first discovered by rational screening. A new Zn-MOF (JLU-MOF221) was successfully constructed based on the pillar-layered strategy to achieve well-isolated AZPY ligand and robust framework. JLU-MOF221 exhibited excellent affinity for 3,3',5,5'-tetramethylbenzidine (TMB) (Km: 0.180 mM; Kcat: 5.72 s-1), as well as a rapid response time (60 s) and high storage stability (87 % activity over 8 months). The study revealed the unique four-electron O2-to-H2O reaction pathway without relying on active oxygen species. Moreover, combining the hydrolysis behavior of benfuracarb and nanozyme inhibition strategy, a colorimetry and fluorescent dual-channel sensor was firstly developed towards benfuracarb, reaching a low limit of detection of 130 ng/mL and 76 ng/mL, respectively. The breakthrough in enzyme activity of organic ligands not only provides an efficient alternative for the traditional assay to detect benfuracarb, but also greatly promotes nanozyme-mediated sensors to a new stage.

Illuminating green fluorescent protein: Characterizing tri-peptide fluorescent chromophore, probing reactivity of cysteines, and unveiling site-directed modifications through mass spectrometry

Bioconjugation technologies enable covalent attachment of diagnostic or therapeutic effectuators onto biological targets, allowing for the precise delivery of desired drugs to the intended targets with enhanced potency, selectivity, specificity, and prolonged duration of action. As the number of bioconjugation techniques has grown enormously, identification and in-depth characterization of in-process products play a critical role in the development of covalent drug conjugates. This is especially significant in light of the increased complexity of novel biotherapeutics derived from biological matrices. This paper describes liquid chromatography-mass spectrometry (LC-MS/MS)-based studies that have contributed to the development of site-specific genetic incorporation of non-natural amino acids (nnAAs) into proteins. A holistic approach was implemented to characterize a wild type green fluorescent protein (wtGFP) and an enhanced green fluorescent protein (eGFP). By using the wtGFP as a pilot and model system, the reactivity of cysteine residues was investigated under different sample processing conditions, followed by a stability evaluation using intact mass measurement. The subsequent complementary proteolytic peptide mappings were performed to achieve full sequence coverage of the proteins, identification of predominant modifications, and granular details of the fluorescent chromophore. The developed method was successfully applied to isolate the eGFP incorporated with nnAA from cells. This enables the verification of the specific site of nnAA incorporation, and the characterization of complex variants using de novo sequencing techniques. MS studies demonstrated that p-azido-phenylalanine (pAzF) was specifically incorporated into the desired site of eGFP with high efficiency and fidelity.

Promoting uniform distribution of zinc ions and stabilizing zinc anode by highly entangled zwitterionic hydrogels

The application of aqueous zinc metal batteries is impeded by dendrite growth and rampant side reaction. Herein, a highly entangled zwitterionic hydrogel of l-carnitine/polyacrylamide is proposed for constructing the highly entangled polyacrylamide network that could form a high-speed channel for ion transport during charging and discharging processes. The interconnected polymer structure promotes uniform distribution of Zn2+, thereby effectively inhibiting dendrite formation. Furthermore, anchoring of zwitterions in zinc anodes facilitate the deposition of Zn2+. Simultaneously, coordination of carboxyl groups in zwitterion with the Zn2+ desolvates it, which helps to suppress side reactions. On the basis of uniform ions distribution and coordination of mechanism, Zn||Zn symmetric batteries exhibit 500 h of reliable plating/stripping at 8 mA cm-2. Additionally, Zn||MnO2 batteries can perform 1, 600 cycles at 0.5 A g-1. And Zn||MnO2 pouch batteries demonstrate superior energy storage under various states.

Recent advances in bioreceptor-based sensing for extracellular vesicle analysis

Extracellular vesicles (EVs) are nanoscale, membrane-bound structures secreted by various cell types into biofluids. They show great potential as biomarkers for disease diagnostics, owing to their ability to carry molecular cargo that reflects their cellular origin. However, the inherent heterogeneity of EVs in terms of size, composition, and source presents significant challenges for reliable detection and analysis. Recent advances in bioreceptor-based biosensor technologies provide promising solutions by offering high sensitivity and specificity in EV detection and characterization. These technologies address the limitations of conventional methods, such as ultracentrifugation and bulk analysis. Biosensors utilizing antibodies, aptamers, peptides, lectins, and molecularly imprinted polymers enable precise detection of EV subpopulations by targeting specific EV surface markers, including proteins, lipids, and glycans. Additionally, these biosensors support multiplexed and real-time analysis while preserving the structural integrity of EVs. This review highlights the transformative potential of combining modern biosensing tools with bioreceptor technologies to advance EV research and diagnostics, paving the way for innovations in disease diagnostics and therapeutic monitoring.

Microfluidic contact lens for continuous monitoring of ocular oxidative stress

Oxidative stress-induced ocular dysfunctions are a significant global health concern. Glutathione (GSH), an abundant antioxidant in tears, can serve as an index for oxidative stress (OS). A coumarin-based fluorescent probe named CCAE was synthesized for GSH monitoring, functioning through structural changes via Michael's addition with GSH and elimination by H2O2, which restores the conjugation structure to assess the severity of OS-induced ocular diseases. CCAE demonstrated a high sensitivity with a detection limit (LOD) of 0.12 mM and reversibility for 15 cycles. A wearable contact lens sensor was developed featuring a microfluidic lens patterned with a 365 nm pulsed laser, requiring 6 μL of tears. CCAE was encapsulated in citric acid-crosslinked poly(vinyl alcohol) film and embedded in poly((hydroxyethyl)methacrylate-co-ethylene glycol)/polyvinylpyrrolidone (poly(HEMA-co-EG)/PVP) lenses. A customized smartphone readout device enabled quantitative GSH readings for point-of-care applications. Tested on an ex vivo porcine anterior eye model, the sensor achieved an LOD of 0.204 mM, within a detection range of 0.62-1.17 mM and 0.13-0.73 mM under mild and severe OS conditions respectively. The sensors maintained operational stability for 2 days and storage stability for 1 week. This reversible GSH contact lens sensor offers a unique platform for diagnosing and monitoring OS-related ocular conditions at point-of-care settings.

Rapid B-Ni charge transfer pathway induced Ni3+/Ni2+ sites reversible conversions enabling efficient urea oxidation assisted hydrogen production

The high energy consumption induced by the sluggish anodic oxygen evolution reaction (OER) severely limits the efficiency of hydrogen production in water splitting. Replacing OER with urea oxidation reaction (UOR) with lower theoretical voltage with nickel-based layered double hydroxides (NiM-LDHs) as the electrocatalyst enables highly efficient hydrogen production. Herein, a reversible Ni3+/Ni2+ conversion mechanism through rapid B-Ni charge transfer for efficient UOR is first reported. The introduction of the B sites accelerates the surface reconstruction of Ni2+ into Ni3+ in B-NiCo-LDH, ensuring the rapid generation of the active Ni3+ species. In the presence of urea, the rapid B-Ni charge transfer accelerates the reduction process of partial Ni3+ into Ni2+ species, avoiding the overaccumulation of Ni3+ and the over-adsorption of *COO on the catalyst, thereby effectively reducing the energy barrier of UOR. Thus, B-NiCo-LDH demonstrates an ultra-low voltage of 1.39 V vs. RHE to deliver 100 mA cm-2 for UOR. More importantly, the constructed urea-assisted water electrolysis electrolyzer by coupling B-NiCo-LDH at the anode and an HER catalyst (Pt/C) at the cathode achieves 100 mA cm-2 with cell voltages of only 1.55 V and 1.57 V, in alkaline freshwater and seawater, respectively, also exhibiting excellent stability for at least 100 h.

H2O2/O2 Self-Supplied Nanoplateform for amplifying oxidative stress to Accelerate Photodynamic/Chemodynamic therapy Cycles

Photodynamic (PDT) and chemodynamic therapies (CDT) relying on reactive oxygen species-mediated treatments mainly face various challenges of hypoxia, endogenous hydrogen peroxide (H2O2) deficiency, and glutathione (GSH) overexpression in the tumor microenvironment. Herein, we propose a novel strategy using a core-shell structured nanocomposite, UCNP@mSiO2@5-ALA-CaO2-Cu(UA@CC). The strategy centers on upconverting NPs and then utilizes mesoporous silica loaded with 5-aminolevulinic acid (5-ALA) to maximize the enrichment of protoporphyrin IX (Pph IX), an intra-tumor photosensitizer. Then in the acidic tumor microenvironment (TME), CaO2 in the outer layer reacts with H2O to form O2, H2O2 and Ca2+, and the released H2O2 serves as an auxiliary "fuel" to induce acceleration of the Fenton-like (Cu2+) reaction and inactivation of the antioxidant GSH enzyme, thus enhancing the tumor cells' Catalysis. Furthermore, under the excitation of a 980 nm laser, 5-ALA-mediated PDT and Cu+-based CDT were initiated. Through interconnected processes of Ca2+ overload, self-supply of H2O2/O2, and enhanced GSH depletion, an accelerated cycling strategy for combined PDT/CDT therapy was established, resulting in amplified oxidative stress and anti-tumor capabilities, which was validated in cancer cells and melanoma mouse models.

Construction of a flexible polymer rechargeable battery based on covalent organic frameworks coated carbon nanotubes anode with six-electron redox activity

Entire polymer rechargeable batteries (EPRBs), which utilize organic polymer materials for both electrodes and electrolytes, are garnering increasing attention due to their numerous appealing attributes, such as high-power density and flexible fabrication, among others. As the core of EPRBs, redox-active polymer electrode with high capacity and electronic conductivity are still lacking. Additionally, the compatibility between polymer cathodes and anodes, as well as between electrodes and polymer electrolytes, requires careful optimization. Here, a covalent organic framework containing triazine and ketone groups (TpTt COF) was employed as the polymer anode. To mitigate the stacking of COF layers and enhance electron diffusion kinetics within the electrode, a few-layered TpTt COF encapsulated by carbon nanotube (CNT@TpTt COF) was synthesized using a facile in-situ growth strategy that exploits π-π interactions. Remarkably, upon activation, CNT@TpTt COF demonstrates six-electron redox reaction, achieving a large reversible capacity of 434 mAh g-1 and superior rate performance. Supported by theoretical calculations and electrochemical behavior analysis, the redox mechanism of CNT@TpTt COF is identified as n-type redox behavior. Furthermore, an innovative dual-ion type EPRB was assembled, featuring an n-type CNT@TpTt COF anode, a p-type polymer cathode, and a solid polymer electrolyte. This EPRB exhibited a discharge capacity of 103 mAh g-1 and holds potential for flexibility. This work may pave the way to the development of high-performance flexible entire polymer rechargeable batteries.

Establishing Ohmic contact with ultra-thin semiconductor layer through magnetron sputtering for dendrite-free Zn metal batteries

The improvement in reversibility and kinetics for Zn metal anodes is crucial to facilitate the further application of aqueous zinc ion batteries. However, the abnormal surface-caused dendrites and parasitic reactions significantly impede the commercial application. Herein, we established Ohmic contact by fabricating an ultrathin semiconductor ZnTe (∼150 nm) layer on the Zn surface via magnetron sputtering to form an electron enrichment region for zinc ions attraction. Particularly, the ZnTe with a higher work function than that of Zn could render a spontaneous electron transfer from Zn to ZnTe, accelerating the zinc ions diffusion, and repelling water and negative sulfate radicals. As a result, the ultrathin ZnTe layer decreases the nucleation and deposition barrier of Zn leading to homogeneous deposition, and restrains the Zn from corrosion and hydrogen evolution reaction. The ZnTe-modified symmetric cells can stably cycle for over 2,400 h and 1,100 h at current density 1 mA cm-2 with area capacity of 1 mAh cm-2 and 5 mAh cm-2, respectively. The full cell matched with CaV8O20·nH2O shows a 63 % capacity retention after 3,000 cycles at 3 A/g. Our work demonstrates that the construction of Ohmic contact could be an effective way to obtain highly reversible Zn anodes and promote the development of aqueous zinc ions batteries.

Fluorinated solvent enhances room-temperature solid-state lithium batteries by weakening Li+ ion and PEO chain interactions

Polyethylene oxide (PEO)-based solid-state batteries have attracted extensive attention due to their scalable processing, flexible and soft interface contact, and excellent compatibility with lithium metal. The low ionic conductivity at room temperature, caused by the strong interaction between PEO chains and lithium ions, however, limits its practical application. Herein, taking the PEO-PAN dual-matrix polymer electrolyte as an example, a weak coordinated solvation structure is enabled by fluoroethylene carbonate (FEC) as a co-solvent during electrolyte preparation. The tiny residual FEC is demonstrated to weaken the interaction between lithium ions and PEO chains while competitively dissociating lithium salts with the residual solvent and anions. In addition, the incorporation of FEC enhances the dispersion of LATP nanoparticle fillers, which reduces the crystallinity of PEO. Furthermore, the anion-derived LiF-rich solid-electrolyte interphase significantly suppresses the formation of lithium dendrites. Consequently, the prepared PEO-PAN-LATP-LiTFSI-5 % FEC (PPLLF) composite solid polymer exhibits an ambient ionic conductivity of ∼ 1 × 10-4 S cm-1 and enables stable cycling for over 450 h in a Li||Li symmetrical battery at room temperature. The assembled Li|PPLLF|LFP full battery delivers a specific capacity of 137.6 mAh/g after 300 cycles at 0.2C, further demonstrating the effectiveness of the solvation manipulation strategy.

Surface reconstruction induced Cu2O/FeO heterojunction towards efficient nitrate-containing wastewater remediation

Electrochemical nitrate-to-nitrogen conversion provides an available approach for efficient waste water remediation. However, high nitrogen selectivity is difficult to achieve, due to inappropriate aquatic H supply for hydrogenation of oxynitride intermediates and relatively high energy barrier for NO bond breakage. In this study, Cu2O/FeO heterojunction is constructed to drive electrochemical nitrate reduction. A straightforward apparent kinetic analysis was performed to define the formation rate of the key nitrogen compounds.Comprehensive structure and electrochemical analysis combined with Density Functional Theory (DFT) calculation were performed to elucidate the underlying mechanism for enhanced nitrate-to-nitrogen conversion efficiency based on Cu2O/FeO heterojunction. FeO introduction is confirmed to beneficial for moderate water cracking, providing right amount of aquatic *H to adapt the hydrogenation processes during nitrate to nitrogen conversion. Moreover, FeO introduction induces the generation of Cu2O/FeO heterojunction. Self-driven local charge redistribution takes place at the Cu2O/FeO heterointerface, resulting in nucleophilic and electrophilic regions. Such unique structure is conducive to targeted asymmetric adsorption of oxynitrides in a configuration of CuONFe, thus facilitating fracture of NO bond and promoting the generation of *N. Excess accumulation of *N is beneficial for nitrogen generation through *N-*N coupling, resulting in high nitrogen selectivity. As a result, the optimized Cu2O/FeO electrode exhibits excellent electrocatalytic nitrate reduction reaction (eNO3RR) performance, featured for a high nitrate removal rate of ∼ 100 % and 81.58 % nitrogen selectivity at -0.7 V (vs. RHE) after 8 h electrolysis.

Reconstructed rich oxygen defects and Ag0 on Pr6O11 surface through interface-defect engineering for enhanced electrochemical carbon dioxide reduction

The design of catalysts for electrochemical CO2 reduction (ECR) is a key challenge for achieving efficient conversion of CO2 into fuels. By concentrating on the active sites of the surface, the strategy of interface and defect engineering has proven effective in enhancing reactivity. Herein, we developed a new Ag/Pr6O11 nanocomposite catalyst with rich interfaces and oxygen defect structures, which induced the in-situ formation of more oxygen vacancies and Ag0 on Pr6O11 during the initial period of ECR. The catalyst exhibits a Faradaic efficiency of 98% for the conversion of CO2 to CO and a mass activity of 48.4 A g-1 at the overpotential of -1.09 V. The metal-support interface active sites and oxygen vacancy defects at the Ag/Pr6O11 interface enhance interfacial catalytic activity and promote CO2 adsorption and activation. Additionally, in-situ infrared and Raman spectroscopy confirmed that the presence of oxygen vacancies and the interface-modified Ag/Pr6O11 enhanced the local microenvironment on the catalyst surface. This improvement accelerated the adsorption and conversion of the key intermediate *COOH, thereby increasing the intrinsic activity of the ECR process and contributing to the inhibitory effect on the hydrogen evolution reaction (HER). This straight forward strategy of interface integration and surface reconstruction offers a potentially versatile approach for guiding the design of ECR electrocatalysts.

Quenching induced Cu and F co-doping multi-dimensional Co3O4 with modulated electronic structures and rich oxygen vacancy as excellent oxygen evolution reaction electrocatalyst

The development of highly efficient non-precious electrocatalysts for the oxygen evolution reaction (OER) remains a significant challenge. In this work, we introduce a highly effective OER electrocatalyst, Cu-F-Co3O4, synthesized by doping copper (Cu) and fluorine (F) into Co3O4 using a quenching method. Both experimental and theoretical calculations reveal that Cu and F incorporation significantly shifts the d-band center closer to the Fermi level, creates abundant oxygen vacancies, and facilitates the reconstruction of the catalyst to form the CuCo2O4-yFy/CuO heterojunction. This structural modification enhances the OER performance of the catalyst. Additionally, the multi-dimensional architecture exposes more active sites and accelerates mass and charge transfer kinetics. The optimal catalyst, Cu-F-Co3O4-0.7, demonstrates a low overpotential of 290 mV at 10 mA·cm-2, along with remarkable stability exceeding 100 h, significantly outperforming both pristine Co3O4 and benchmark RuO2 electrocatalysts. These findings offer new insights into activating surface reconstruction in spinel oxides by engineering both anion and cation defects for water oxidation.

Ameliorating water splitting by entropy regulation and electronic structure engineering on pristine Prussian blue analog

Electrochemical water splitting is the most promising green method for hydrogen production. In this work, the traditional Prussian blue analogs were endowed with the new concept of high entropy to bring a breakthrough in electrocatalytic performance. A classic two-step synthetic strategy was employed to fabricate the high-entropy FeCoNiCr6P nanoparticle via phosphating the FeCoNiCr6, which was prefabricated using a facile coprecipitation method. The phosphides can trap protons by acting as bases to promote the discharge step faster. FeCoNiCr6P requires a lower overpotential of only 268.3 mV at a current density of 100 mA cm-2 for OER. The FeCoNiCr6P//FeCoNiCr6P electrochemical water splitting couple can realize a low voltage of 1.58 V to at 10 mA cm-2 current density. Furthermore, the electronic states and coordination environment of catalyst active sites were investigated to get deeper insight into material design.

Oxygen doping-triggered electron redistribution in cobalt-rich sulfide for efficient electrocatalytic water splitting

Cobalt-rich sulfide (Co9S8) holds great promise as an electrocatalyst for water splitting, but its performance for hydrogen evolution reaction (HER) in alkaline and neutral media is limited by sluggish water dissociation kinetics. Herein, we find that moderate oxygen doping within Co9S8, preferentially at the interstitial sites, triggers significant electron redistribution via Co-O-S bridges, which decreases the local electron density of Co and S sites. This treatment enhances H2O adsorption and dissociation at the Co-sites and optimizes H* adsorption/desorption at the S-sites, notably on the high-index (311) facet, thus accelerating the water dissociation kinetics. The oxygen-doped Co9S8 catalyst, dominated by the (311) crystal plane, demonstrates remarkable HER activity and stability in alkaline solution, with a low overpotential of 142 mV at 10 mA cm-2 and a Tafel slope of 96 mV dec-1, outperforming most Co9S8-based catalysts. Under neutral condition, it exhibits a low overpotential of 264 mV at 10 mA cm-2. Further applied in an anion exchange membrane water electrolyzer, it reaches 150mA cm-2 at 1.70 V, surpassing the commercial Pt/C (134 mA cm-2). This oxygen doping-triggered electron redistribution strategy paves new ways for developing highly efficient transition metal-based electrocatalysts for sustainable energy applications.

Machine learning enabled protein secondary structure characterization using drop-coating deposition Raman spectroscopy

Protein structure characterization is critical for therapeutic protein drug development and production. Drop-coating deposition Raman (DCDR) spectroscopy offers rapid and cost-effective acquisition of vibrational spectral data characteristic of protein secondary structures. Amide I region (1600 -1700 cm-1) and amide II region (1500-1600 cm-1) of DCRD Raman spectra measured for model proteins of varying molecular size and structural distribution were first analyzed by peak fitting for their proportions of six secondary structure motifs: α-helices, 310-helices, β-sheets, turns (β-turns and γ-turns), bends, and random coil. The high spectral resolution and superior signal-to-noise of DCDR spectra made it possible to estimate all six structural motifs at accuracy comparable to X-ray crystallographic measurement. The ease of DCDR measurement was further explored by introducing machine learning algorithm to spectroscopic data analysis. Partial Least Squares (PLS) regression modeling was used as a machine learning tool to predict the protein secondary structural composition from the amide I band of model proteins. Once developed on a training sample set, the PLS model was tested by applying to a sample set that was not used previously for model development. Low prediction errors were achieved at 1.36 %, 0.78 %, 0.42 % 0.41 %, 0.81 %, and 0.52 %, respectively for the six structural component, α-Helix, β-Sheet, 310-helices, random, turns, and bends. The PLS model was further tested on an independent sample set that contains three IgG proteins. The proportion ofα-Helix, β-Sheet, 310-Helix were estimated with an error of 3.1 %, 2.3 % and 2.8 %, respectively.

Enhancing pesticide detection: The role of serine in lipopeptide nanostructures and their self-assembly dynamics

In this research, we studied two novel lipopeptide sequences containing the amino acid serine (SPRWG) with one (compound 1) or two aliphatic tails (compound 2) to optimize the detection capabilities for organophosphate pesticides, specifically glyphosate. The study comprehensively explored how the incorporation of serine influences the physicochemical properties and supramolecular assembly of the lipopeptides, leading to enhanced interactions with glyphosate. Advanced analytical methods were employed to investigate these modifications, including fluorescence spectroscopy, circular dichroism, and small-angle X-ray scattering (SAXS). The results showed that serine significantly reduces the critical aggregation concentration, increases the hydrophilicity of the lipopeptides, and promotes the formation of distinct secondary structures-β-turns in compound 1 and β-sheets in compound 2. Moreover, isothermal titration calorimetry (ITC) and molecular dynamics confirmed the improved binding affinity with glyphosate strongly modulated by pH and pesticide load. Compound 1, with one alkyl chain, demonstrated notably higher catalytic activity and sensitivity linked to its pH equilibrium and structural features, marking it as particularly effective for acetylcholinesterase mimicry in pesticide detection. Density functional theory and molecular dynamics calculations showed that, when compared to the PRWG sequence, SPRWG has more unprotonated N-terminal sites due to a lower pKa, more beta-turn-like structures that improve stabilization. Besides promotes more hydrogen bonds between N-(phosphonomethyl)glycine (PNG, commonly known as glyphosate) and aggregates across a wide pH range and P/L; which explains its enhanced reactivity in Ellman's test and better inhibitory effects under the influence of PNG. Our results suggest that serine-functionalized lipopeptides have great potential as biomimetic sensors in environmental monitoring.

Smart photo-driven composite system containing thermosensitive P(NIPAM-NVK) and photoactive PANI for the rapid removal of anionic dyes

A smart composite system based on thermosensitive polymers and photosensitive polyaniline (PANI) was constructed in this work, enabling efficient photo-driven adsorption and separation of anionic dyes within a short time. Thermosensitive copolymers (P(NIPAM-NVK)) of N-isopropylacrylamide (NIPAM) and N-vinylcarbazole (NVK) with adjustable low critical solution temperatures (LCST) were synthesized via a free radical copolymerization method. PANI was then composited with P(NIPAM-NVK) as a photothermal agent and dye adsorbent. The developed P(NIPAM-NVK)/PANI composite systems showed a rapid temperature increase under visible light irradiation, triggering the transition of P(NIPAM-NVK) from the sol state to a bulk gel state. Simultaneously, PANI and Congo Red (CR) anionic dye were efficiently encapsulated within the gel state of P(NIPAM-NVK) via intermolecular interactions, facilitating the rapid separation of aqueous CR through a direct solid-liquid process to yield clean water. The P(NIPAM-NVK10)/PANI0.5 composite system afforded a removal efficiency > 98 % for CR (80 mg/L) within 5 min under visible light illumination. These findings hold great promise for the eco-friendly treatment of dye-containing wastewater.

Tailoring curcumin ternary complex nanocrystals via microfluidic mediated assembly: Stability, solubility, bioaccessibility and formation mechanism

Microfluidic technique was employed to precisely modulate both the microenvironment and composition, enabling the dynamic assembly of curcumin, soy protein isolates, and rhamnolipid into ternary nanocrystals through hydrogen bonding and hydrophobic interactions. As the concentration of rhamnolipid increased, the loading capacity of curcumin in ternary complex nanocrystals rose from 4.23 % to 10.82 %, while its water dispersibility and bioaccessibility enhanced by 141.94- to 664.67-fold and 5.11- to 6.49-fold, respectively. Moreover, the stability of curcumin in ternary complex nanocrystals was significantly enhanced during both storage and exposure to UV light. The longest half-life of curcumin in the nanocrystals increased from 65.39 days to 385.08 days during storage at 25 °C, and from 87.74 min to 198.04 min under UV light. These findings provide important insights for the development of bio-assemblies, and the resulting complex nanocrystals can be used as pigment or bioactivity in foods, cosmetics and pharmaceuticals.

Contact electrocatalysis-based synthesis of multimetal catalysts for the electrocatalytic oxygen evolution reaction

Hydrogen energy has garnered considerable attention as a clean and sustainable alternative to fossil fuels in the global pursuit of carbon neutrality. Cost-effective hydrogen production requires the development of efficient and scalable water-splitting catalysts. In this regard, herein, we use ultrasonically driven contact electrocatalysis method to synthesize multimetal hydroxide catalysts for the oxygen evolution reaction (OER). This synthesis approach, performed under mild conditions, utilizes carbon paper, nickel foam, or copper foam as the substrate in metal salt solutions, achieving rapid catalyst formation (within 30 s). Among catalysts containing combinations of >10 metals formed by this process, iron-cobalt oxyhydroxide (FeCoOOH) exhibits notable OER performance in 1.0 M KOH. FeCoOOH achieves an overpotential of 351 mV at a current density of 100 mA cm-2 with a Tafel slope of 40.2 mV dec-1 on carbon paper, maintaining stability over 50 h of continuous operation. Comparative experiments demonstrate that ultrasonic treatment is crucial for the low-cost and scalable production of high-efficiency catalysts. Overall, this synthesis of advanced OER catalysts can benefit large-scale hydrogen production technologies.

In vitro investigation of epigenetic regulators related to chemo-resistance and stemness of CD133+VE cells sorted from U87MG cell line

Glioblastoma (GBM) is the most common and malignant adult primary brain tumor with frequent relapse and resistance to therapies. Glioma stem cells, a rare population, is thought to be the reason behind the treatment's failure. It is imperative to investigate the disease mechanisms and identify the biomarkers by which glioma stem cells would contribute to treatment relapse and resistance to already available chemotherapeutic agents. The CD133+VE cells were isolated from U87MG cell line and characterized by morphological features, cell viability, self-renewal efficiency, migration potential and karyotyping. Doxorubicin Cisplatin, Irinotecan, Etoposide and Temozolomide were used to determine the anti-proliferative effect on CD133+VE cells. Confocal microcopy was used to localize the chemotherapeutic agents in the CD133+VE cells. In quest of epigenetic biomarkers, RNA sequencing was performed to find the role of lncRNAs in stemness and resistance to therapies. U87cell line and CD133-VE cells were kept as controls for all the experiments. It was found that CD133+VEcells were highly proliferative with increased migration potential, elevated IC50 values against chemotherapeutic agents and showed distinct karyotyping related to pluripotency. Chemotherapeutic agent such as Doxorubicin was localized outside the nucleus revealing the drug resistance as evident by confocal microscopy. RNA sequencing revealed 126 differentially expressed lncRNAs (DELs) in CD133+VEcells among which lncRNA LOXL1-AS1 was highly upregulated and lncRNA PAX8-AS1 was significantly downregulated. These lncRNAs has been reported to be related to drug resistance, migration and epithelial- to- mesenchymal transmission (EMT), self-renewal and stemness properties contributing to poor prognosis and disease relapse.

A Hemicyanine-based dual function fluorescent probe for rapid detecting sulfur dioxide and viscosity in food sample and living cells

Sulfur dioxide is a critical factor in evaluating food safety, as excessive intake can lead to various adverse reactions. Additionally, viscosity is a key indicator of food quality. However, to date, dual-response probes capable of detecting both viscosity and sulfur dioxide in food remain scarce. In this study, we present a novel fluorescent probe, BZID-OH, designed for the simultaneous detection of sulfur dioxide and viscosity in food. Moreover, BZID-OH is also effective for sulfur dioxide detection in living cells. These findings suggest that BZID-OH has the potential to serve as an effective dual-response fluorescent probe for monitoring both sulfur dioxide levels and viscosity in food, offering a valuable tool for food safety and quality assessment.

ESDPT induced dual-tautomer fluorescence of newly designed 1,8-dihydroxy-2-naphthaldehyde analogue with different solvent polarity

Excited-state intramolecular double proton transfer (ESDPT) has long been a subject of attention due to its crucial role in both fundamental exploration and designing related functional materials. In this work, the static and dynamical characterization from first-principles are performed to reveal the ESDPT mechanism of DHNA-2, a molecule designed based on 1,8-dihydroxy-2-naphthaldehyde (DHNA). The modification could provide easier ESDPT with favorable thermodynamics. More importantly, the DHNA-2 possesses enhanced absorption and fluorescence intensity (Δf > 100 %) due to the additional π-conjunction. Meanwhile, the distinct dual-tautomer emission (Δλ > 90 nm) is observed from the first and second PT products in excited states. The corresponding PT paths are demonstrated by constructing energy profiles and potential energy surfaces in both the ground and excited states. Moreover, we examined the influence of solvents with different polarities on conformational energies and spectra properties. Inspection of infrared spectroscopy, visualization of weak interactions, and bond order calculations indicate that photoexcitation could strengthen the intramolecular hydrogen bonds and promote the ESDPT. The H-bond strengthening mechanism caused by electron rearrangement during photoexcitation is also confirmed through the analyses of frontier molecular orbitals and charge population calculations. Additionally, the dynamic trajectories are shown to be in good agreement with static calculations, revealing the conformational changes associated with PT. Considering the improved photoluminescence and optical sensitivity for solvent polarity, the newly designed DHNA-2 is expected to provide multi-perspective reference for understanding the essence of ESDPT and inspiration for polarity-sensitized molecular design.

A contemporary overview on quantum dots-based fluorescent biosensors: Exploring synthesis techniques, sensing mechanism and applications

In the epoch of bioinformatics, pivotal biomedical scrutiny and clinical diagnosis hinge upon the unfolding of highly efficacious biosensors for intricate and targeted identification of specific biomolecules. In pursuit of developing robust biosensors endowed with superior sensitivity, precise selectivity, rapid performance, and operational simplicity, semiconductor QDs have been acknowledged as pivotal and advantageous entities. In this review, we present a comprehensive analysis of the latest unfolding within the domain of QDs used in fluorescent biosensors for the detection of diverse biomolecular entities, encompassing proteins, nucleic acids, and a range of small molecules, with an emphasis on the synthesis methodologies of QDs employed and mechanism behind sensing. Additionally, this review delves into several pivotal facets of QD-based fluorescent biosensors in detail, such as surface functionalization methodologies aimed at enhancing biocompatibility and improving target specificity. The challenges and future perspectives of QD-based fluorescent biosensors are also considered, emphasizing the necessity of ongoing multidisciplinary research to realize their full potential in enhancing personalized medicine and biomedical diagnostics.

Targeted vancomycin delivery via in situ albumin conjugation and acid-triggered drug release for reduced nephrotoxicity

Vancomycin has long been considered as the last-resort antibiotic for tacking extremely severe infections caused by methicillin-resistant Staphylococcus aureus (MRSA). However, its clinical application is limited by dose-limiting nephrotoxicity. In this study, we report a novel in situ albumin conjugation and acid sensitive prodrug strategy to selectively release vancomycin at the infection site, thereby minimizing the accumulation of vancomycin in the kidney and thus reducing its nephrotoxicity. We synthesized and evaluated four vancomycin prodrugs 13a-d and found that 13c effectively bound to plasma albumin in vitro, and released vancomycin rapidly at the infection site. Its therapeutic effect against MRSA USA300 infection was comparable to that of free vancomycin at 10 mg/kg. In vivo safety assessments demonstrated that 13c did not exhibit significant nephrotoxicity at 50 mg/kg, whereas vancomycin caused obvious nephrotoxicity at the same dose. This work represents the first example of utilizing albumin for targeted delivery of antibiotic to the bacterial infection site to mitigate the common dose-limiting nephrotoxicity of vancomycin, and this strategy may also be applicable to other aminoglycoside antibiotics with nephrotoxicity.

Discovery of the first-in-class DOT1L PROTAC degrader

DOT1L is the lysine methyltransferase responsible for histone H3 lysine 79 (H3K79) methylation and plays a crucial role in leukemia progression. Furthermore, DOT1L has biological functions that are independent of its methyltransferase activity. Therefore, targeting and degrading DOT1L with PROteolysis TArgeting Chimeras (PROTACs) could represent a promising therapeutic strategy. Here, we report the discovery of the first-in-class DOT1L PROTAC degrader, compound 13 (MS2133), which potently induces DOT1L degradation in a concentration- and time-dependent manner, without affecting DOT1L mRNA expression. The DOT1L degradation induced by 13 requires binding to the E3 ligase von Hippel-Lindau (VHL) and DOT1L and occurs through the ubiquitin-proteasome system. 13 is selective for DOT1L over other methyltransferases and effectively inhibits the growth of mixed lineage leukemia-rearranged (MLL-r) leukemia cells while having no toxicity on normal cells. Overall, 13 is a valuable chemical biology tool for further studying functions of DOT1L and a potential therapeutic for DOT1L-dependent cancers.

Recent advances in developing bioorthogonally activatable photosensitizers for photodynamic therapy

Photodynamic therapy (PDT) is a promising and powerful cancer therapeutic modality, which can generate cytotoxic reactive oxygen species (ROS) from light-irradiated photosensitizers (PSs) to eradicate tumors. To overcome the drawbacks of currently used PSs, researchers have leveraged the advantages of bioorthogonal reactions to design diverse bioorthogonally activatable photosensitizers with excellent tumor selectivity, high ROS generation controllability, and low adverse effect for effective antitumor photodynamic therapy. In this review, we comprehensively summarize and highlight the recent advances in the development of bioorthogonally activatable photosensitizers, including the structure types, designing strategies, activation patterns, photophysical properties, ROS generation efficiency, in vitro and in vivo activities, biological applications, and limitations. We also provide directions and perspectives to address the therapeutic challenges of bioorthogonally activatable photosensitizers for promoting clinical applications. We believe that the principles summarized here will offer useful references for further development of next-generation advanced intelligent photosensitizers and related strategies to realize precise and efficient tumor treatment in the future.

Theoretical study of modified multiple dual-mode elution counter-current chromatography based on chiral separation

The fact that both phases are liquids makes it simple to implement counter-current chromatography (CCC), which involves alternating elution modes and phase roles during the separation process. Using two distinct multiple dual-mode (MDM) elution techniques for chiral separation, the team demonstrated a superior separation effect in a prior study. When selecting a chiral selector with high enantiomer recognition capability is difficult, the separation efficiency of the CCC column can be enhanced through multiple cycles. This approach facilitates the preparation of enantiomers that are challenging to isolate under classical CCC conditions. A straightforward mathematical model was created in this study to forecast the number of cycles and the mode conversion time needed for the separation process after the modified MDM method was further examined theoretically. After modeling molecules, the theoretical model was confirmed, and the outcomes generally agreed with the calculations from the theoretical model. This offers substantial support for the modified MDM method's real-world implementation in chiral separation.