Effect of shape on the transport and retention of nanoplastics in saturated quartz sand

Nanoplastics (NPs) pose great challenges to soil-groundwater systems. This study investigated the transport and retention of self-synthesized 0.5-μm polystyrene NPs with different shapes using column experiments. The regular NPs were with spherical shapes, while the irregular NPs were with toroid-like shapes. The toroid-like shapes were the irregular shapes (with low aspect ratio) which have not been studied yet. The explorations were carried out in both 5-25 mM NaNO3 and 1-10 mM Ca(NO3)2 solutions. Both breakthrough curves (BTCs) and retained profiles (RPs) were monitored. Our findings uncovered a clear disparity in the transport of irregular and regular NPs, with irregular particles exhibiting lower transport ability compared to the regular ones. For example, the average breakthrough plateaus of the regular and irregular NPs were ∼0.9 and ∼0.5, respectively, in 10 mM NaNO3. In-depth theoretical analysis indicated that the lower XDLVO interaction energy barrier between the irregular NPs and quartz sand was one factor, and the greater margination of irregular NPs on quartz sand, as verified by the numerical simulation, was another factor leading to the decreased transport and increased retention of the irregular NPs. The obtained results highlighted the significance of considering particle shape in future modelling and predicting the fate of NPs in real environmental circumstances.

Toxicological effects, absorption and biodegradation of bisphenols with different functional groups in Chromochloris zofingiensis

Bisphenols (BPs) are recognized as endocrine disrupting compounds and have garnered increasing attention due to their widespread utilization. However, the varying biological toxicities and underlying mechanisms of BPs with different functional groups remain unknown. In the present study, the toxic effects of four BPs (BPA, BPS, BPAF, and TBBPA) on a photosynthetic microalgae Chromochloris zofingiensis were compared. Results showed that halogen-containing BPs exhibited higher cellular uptake, leading to more severe oxidative stress, lower photosynthetic efficiency, and greater accumulation of starch and lipids. Specifically, TBBPA with bromine groups showed a greater toxicity than BPAF with fluorine groups, possibly due to the incomplete debromination in C. zofingiensis. Transcriptomic analysis revealed that halogen-containing BPs triggered greater number of differentially expressed genes (DEGs), and only 64 common DEGs were found among different BPs, indicating that the effects of BPs with different functional groups varied greatly. Genes involved in endocytosis, peroxisomes, and endoplasmic reticulum protein processing pathways were mostly upregulated across different BPs, while photosynthesis-related genes showed varied expression, possibly due to their distinct functional groups. Additionally, SIN3A, ZFP36L, CHMP, and ATF2 emerged as potential key regulatory genes. Overall, this study thoroughly explained how functional groups impact the toxicity and biodegradation of BPs in C. zofingiensis.

Rapid, sensitive, and non-destructive on-site quantitative detection of nanoplastics in aquatic environments using laser-backscattered fiber-embedded optofluidic chip

A definitive link between the micro- and nano-plastics (NPLs) and human health has been firmly established, emphasizing the higher risks posed by NPLs. The urgent need for a rapid, non-destructive, and reliable method to quantify NPLs remains unmet with current detection techniques. To address this gap, a novel laser-backscattered fiber-embedded optofluidic chip (LFOC) was constructed for the rapid, sensitive, and non-destructive on-site quantitation of NPLs based on 180º laser-backscattered mechanism. Our theoretical and experimental findings reveal that the 180º laser-backscattered intensities of NPLs were directly proportional to their mass and particle number concentration. Using the LFOC, we have successfully detected polystyrene (PS) NPLSs of varying sizes, with a minimum detection limit of 0.23 μg/mL (equivalent to 5.23 ×107 particles/mL). Moreover, PS NPLs of different sizes can be readily differentiated through a simple membrane-filtering method. The LFOC also demonstrates high sensitivity in detecting other NPLs, such as polyethylene, polyethylene terephthalate, polypropylene, and polymethylmethacrylate. To validate its practical application, the LFOC was used to detect PS NPLs in various aquatic environments, exhibiting excellent accuracy, reproducibility, and reliability. The LFOC provides a simple, versatile, and efficient tool for direct, on-site, quantitative detection of NPLs in aquatic environments.

Atomically dispersed copper-zinc dual sites anchored on nitrogen-doped porous carbon toward peroxymonosulfate activation for degradation of various organic contaminants

Single-atom catalysts (SACs) have been widely studied in Fenton-like reactions, wherein their catalytic performance could be further enhanced by adjusting electronic structure and regulating coordination environment, although relevant research is rarely reported. This text elucidates fabrication of dual atom catalyst systems aimed at augmenting their catalytic efficiency. Herein, atomically dispersed copper-zinc (Cu-Zn) dual sites anchored on nitrogen (N)-doped porous carbon (NC), referred to as CuZn-NC, were synthesized using cage-encapsulated pyrolysis and host-guest strategies. The CuZn-NC catalyst exhibited high activity in activation of peroxymonosulfate (PMS) for degradation of organic pollutants. Based on synergistic effects of adjacent Cu and Zn atom pairs, CuZn-NC (PMS) system achieved 94.44 % bisphenol A (BPA) degradation in 24 min. The radical pathway predominated, and coexistence of non-radical species was demonstrated for BPA degradation in CuZn-NC/PMS system. More importantly, CuZn-NC/PMS system showed generality for degradation of various refractory contaminants. Our experiments indicate that CuZn-N sites on CuZn-NC act as active sites for bonding PMS molecules with optimal binding energy, while pyrrolic N sites are considered as adsorption sites for organic molecules. Overall, this research designs diatomic site catalysts (DACs), with promising implications for wastewater treatment.

Tailoring the covalent organic frameworks based polymer materials for solar-driven atmospheric water harvesting

Atmospheric water harvesting through reticular materials is an innovation that has the potential to change the world. Here, this study offers a technique for creating a solar-powered hygroscopic polymer material for atmospheric water harvesting with the reticular materials. The results show that the porous hygroscopic polymer materials can achieve high performance with high vapor capture (up to ac. 28.8-49.7 mg/g at 28-38 %RH and 25  ℃), rapid photothermal conversion efficiency (up to 32.2 ℃ within 15 min under 1000 W/m-2 light at 25 ℃), a low desorption temperature (lower than 40 ℃), and an effective water release rate. Besides, the material also has excellent water-retention properties, which can effectively store desorbed liquid water in polymer networks for use by vegetation during water demand periods. The strategy opens new avenues for atmospheric water-harvesting materials, which will hopefully solve the global crisis of freshwater shortages.

Enhancing the Lewis acidity of single atom Tb via introduction of boron to achieve efficient photothermal synergistic CO2 cycloaddition

Nowadays, it is becoming increasingly urgent to lower the escalating carbon dioxide (CO2) to reduce greenhouse effect. Fortunately, it is an ideal strategy by using the inexhaustible solar energy as the driving force to manipulate the cycloaddition reaction, the atomic efficiency of which is 100 %. This work represents the first attempt on utilization of rare-earth metal Tb with atomic dispersion, and the structure of Tb coordinated with 4 N-atoms and 2B-atoms was constructed on interconnected carbon hollow spheres. The introduction of electron-deficient B reduces the electron density of Tb, thereby boosting Lewis acidity and promoting the occurrence of ring-opening reaction. The mechanism exploration enunciates that TbN4B2/C is a photothermal synergistic catalyst, the combined action of photogenerated electrons and strong Lewis acidic site of Tb reduces the free energy of the rate-determining step, and then improving the yield of cyclic carbonate up to 739 mmol g-1h-1.

The Mn-doped CeO2 nanoparticles with enhanced peroxidase-like activity for one-pot analysis of glucose at neutral pH based on bio-inorganic cascade reactions

Enzyme catalytic cascade reactions based on peroxidase nanozymes and natural enzymes have aroused extensive attention in analytical fields. However, a majority of peroxidase nanozymes perform well only in acidic environments, resulting in their optimal pH mismatch with a neutral pH of natural enzymes, further restricting their application in biochemical sensing. Herein, Mn-doped CeO2 (Mn/CeO2) performing enhanced peroxidase-like activity at neutral conditions was prepared via a facile and feasible strategy. An effective enzyme cascade catalysis system via integrating glucose oxidase (GOx) with Mn/CeO2 was developed for one-pot detection of glucose in serum at neutral conditions. Using one-pot multistep catalytic reactions, this work provided a detection platform that allows for faster detection and easier operations than traditional methods. Under optimized conditions, our assay performed a sensitive detection of glucose ranging from 2.0 μΜ to 300 μΜ and a low detection limit of 0.279 μΜ. Notably, favorable analytical outcomes for glucose detection in serum samples were obtained, exhibiting potential applications in clinical diagnosis.

Strong metal-support interaction (SMSI) in environmental catalysis: Mechanisms, application, regulation strategies, and breakthroughs

The strong metal-support interaction (SMSI) in supported catalysts plays a dominant role in catalytic degradation, upgrading, and remanufacturing of environmental pollutants. Previous studies have shown that SMSI is crucial in supported catalysts' activity and stability. However, for redox reactions catalyzed in environmental catalysis, the enhancement mechanism of SMSI-induced oxygen vacancy and electron transfer needs to be clarified. Additionally, the precise control of SMSI interface sites remains to be fully understood. Here we provide a systematic review of SMSI's catalytic mechanisms and control strategies in purifying gaseous pollutants, treating organic wastewater, and valorizing biomass solid waste. We explore the adsorption and activation mechanisms of SMSI in redox reactions by examining interfacial electron transfer, interfacial oxygen vacancy, and interfacial acidic sites. Furthermore, we develop a precise regulation strategy of SMSI from systematical perspectives of interface effect, crystal facet effect, size effect, guest ion doping, and modification effect. Importantly, we point out the drawbacks and breakthrough directions for SMSI regulation in environmental catalysis, including partial encapsulation strategy, size optimization strategy, interface oxygen vacancy strategy, and multi-component strategy. This review article provides the potential applications of SMSI and offers guidance for its controlled regulation in environmental catalysis.

Patterned graphene: An effective platform for adsorption, immobilization, and destruction of SARS-CoV-2 Mpro

To address the ongoing challenges posed by the SARS-CoV-2 and potentially stronger viruses in the future, the development of effective methods to fabricate patterned graphene (PG) and other precisely functional products has become a new research frontier. Herein, we modeled the "checkerboard" graphene (CG) and stripped graphene (SG) as representatives of PG, and studied their interaction mechanism with the target protein (Mpro) by molecular dynamics simulation. The calculation results on the binding strength and the root mean square deviation values of the active pocket revealed that PG is an effective platform for adsorption, immobilization, and destruction of Mpro. Specifically, CG is found to promote disruption of the active pocket for Mpro, but the presence of "checkerboard" oxidized regions inhibits the adsorption of Mpro. Meanwhile, the SG can effectively confine Mpro within the non-oxidized strips and enhances their binding strength, but doesn't play well on disrupting the active pocket. Our work not only elucidates the biological effects of PGs, but also provides guidance for their targeted and precise utilization in combating the SARS-CoV-2.

A persistent mineralization process in alveolar bone throughout the postnatal growth stage in rats

OBJECTIVE

Alveolar bone quality is essential for the maxillofacial integrity and function, and depends on alveolar bone mineralization. This study aims to investigate the in vivo changes in alveolar bone mineralization, from the perspective of mineral deposition and crystal transition in postnatal rats.

DESIGN

Nine postnatal time points of Wistar rats, ranging from day 1 to 56, were set to obtain the maxillary alveolar bone samples. Each time point consisted of ninety rats, with 45 females and 45 males. Macromorphology of alveolar bone was reconducted by Micro-Computed Tomography and the mineral content was quantified via Thermogravimetric analysis, Scanning Electron Microscope, High-Resolution Transmission Electron Microscopy and vibrational spectroscopy. Furthermore, the crystallinity and composition were characterized by vibrational spectroscopy, X-ray Diffraction, X-ray Photoelectron Spectroscopy and Selected Area Electron Diffraction.

RESULTS

The progressive increase of mineral deposition was accompanied by substantial growth in alveolar bone mass and volume in postnatal rats. Whereas the mineral percentage initially decreased and then increased, reaching a nadir on postnatal day 14 (P14) when tooth eruption was first observed. Besides, localized mineralization was initiated by the formation of amorphous precursors and then converted into mineral crystals, while there was no statistically significant change in the average crystallinity of the bone during growth.

CONCLUSION

Mineralization of alveolar bone is ongoing throughout the early growth in postnatal rats. Mineral deposition increases with age, whereas the crystallinity remains stable within a certain range. Besides, the mineral percentage reaches its lowest point on P14, which may be attributed to tooth eruption.

Diving into the metabolic interactions of titanium dioxide nanoparticles in "Sparus aurata" and "Ruditapes philippinarum"

The biological response to nanomaterials exposure depends on their properties, route of exposure, or model organism. Titanium dioxide nanoparticles (TiO2 NPs) are among the most used nanomaterials; however, concerns related to oxidative stress and metabolic effects resulting from their ingestion are rising. Therefore, in the present work, we addressed the metabolic effects of citrate-coated 45 nm TiO2 NPs combining bioaccumulation, tissue ultrastructure, and proteomics approaches on gilthead seabream, Sparus aurata and Japanese carpet shell, Ruditapes philippinarum. Sparus aurata was exposed through artificially contaminated feeds, while R. philippinarum was exposed using TiO2 NPs-doped microalgae solutions. The accumulation of titanium and TiO2 NPs in fish liver is associated with alterations in hepatic tissue structure, and alteration to the expression of proteins related to lipid and fatty acid metabolism, lipid breakdown for energy, lipid transport, and homeostasis. While cellular structure alterations and the expression of proteins were less affected than in gilthead seabream, atypical gill cilia and microvilli and alterations in metabolic-related proteins were also observed in the bivalve. Overall, the effects of TiO2 NPs exposure through feeding appear to stem from various interactions with cells, involving alterations in key metabolic proteins, and changes in cell membranes, their structures, and organelles. The possible appearance of metabolic disorders and the environmental risks to aquatic organisms posed by TiO2 NPs deserve further study.

On the possibility of implementing a quantum entanglement distribution in a biosystem: Microtubules

The paper considers the possibility of implementing a quantum entanglement distribution in the cell microtubule. It has been shown that a quantum entanglement distribution proposed in the paper determines the process of quantum state teleportation through microtubule tryptophan chain. The work shows that the system of tryptophans in a microtubule essentially is a quantum network that consists of: spatially spaced nodes - tryptophans, quantum communication channels connecting tryptophans and qubits transmitted through these communication channels. The connection between the process of quantum teleportation in living nature and its classical analogue is discussed. The quantum protocol established in the work determines the possible principle of quantum information transmission in biosystems and also in the similar nanostructures.

Identification of ferroptosis-associated tumor antigens as the potential targets to prevent head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSC) represents nearly 90% of all head and neck tumors. The current treatment modality for HNSC patients primarily involves surgical intervention and radiotherapy, but its therapeutic efficacy remains limited. The mRNA vaccine based on tumor antigens seems promising for cancer treatment. Ferroptosis, a novel form of cell death, is linked to tumor progression and cancer immunotherapy. Nevertheless, the effectiveness of ferroptosis-associated tumor antigens in treating HNSC remains uncertain. In this study, we identified three ferroptosis-associated tumor antigens, namely caveolin1 (CAV1), ferritin heavy chain (FTH1), and solute carrier 3A2 (SLC3A2), as being overexpressed and mutated based on data obtained from The Cancer Genome Atlas and Gene Expression Omnibus databases. These antigens were strongly associated with poor prognosis and infiltration of antigen-presenting cells in HNSC. We further identified two ferroptosis subtypes (FS1 and FS2) with distinct molecular, cellular, and clinical properties to identify antigen-sensitive individuals. Our findings indicate that FS1 exhibits an immune "hot" phenotype, whereas FS2 displays an immune "cold" phenotype. Additionally, differential expression of immunogenic cell death modulators and immune checkpoints was observed between these two immune subtypes. Further exploration of the HNSC's immune landscape revealed significant heterogeneity among individual patients. Our findings suggest that CAV1, FTH1, and SLC3A2 are potential targets to prevent HNSC in FS2 patients. Overall, our research reveals the potential of ferroptosis-associated mRNA vaccines for HNSC and identifies an effective patient population for vaccine treatment.

Recent advances in fluorescent probes for ATP imaging

Adenosine-5'-triphosphate (ATP) is a critical biological molecule that functions as the primary energy currency within cells. ATP synthesis occurs in the mitochondria, and variations in its concentration can significantly influence mitochondrial and cellular performance. Prior studies have established a link between ATP levels and a variety of diseases, such as cancer, neurodegenerative conditions, ischemia, and hypoglycemia. Consequently, researchers have developed many fluorescent probes for ATP detection, recognizing the importance of monitoring intracellular ATP levels to understand cellular processes. These probes have been effectively utilized for visualizing ATP in living cells and biological samples. In this comprehensive review, we categorize fluorescent sensors developed in the last five years for ATP detection. We base our classification on fluorophores, structure, multi-response channels, and application. We also evaluate the challenges and potential for advancing new generations of fluorescence imaging probes for monitoring ATP in living cells. We hope this summary motivates researchers to design innovative and effective probes tailored to ATP sensing. We foresee imminent progress in the development of highly sophisticated ATP probes.

2-Methylbenzimidazole-copper nanozyme with high laccase activity for colorimetric differentiation and detection of aminophenol isomers

Laccase is well-known for its eco-friendly applications in environmental remediation and biotechnology, but its high cost and low stability have limited its practical use. Therefore, there is an urgent need to develop efficient laccase mimetics. In this study, a novel laccase-mimicking nanozyme (MBI-Cu) was successfully synthesized using 2-methylbenzimidazole (MBI) coordinated with Cu2+ by mimicking the copper active site and electron transfer pathway of natural laccase. MBI-Cu nanozyme exhibited excellent catalytic activity and higher stability than laccase, and was utilized to oxidize a series of phenolic compounds. Environmental pollutant aminophenol isomers were found to display different color in solution when catalytically oxidized by MBI-Cu, which provided a simple and feasible method to identify them by the naked eye. Based on the distinct absorption spectra of the oxidized aminophenol isomers, a colorimetric method for quantitatively detecting o-AP, m-AP, and p-AP was established, with detection limits of 0.06 μM, 0.27 μM, and 0.18 μM, respectively. Furthermore, by integrating MBI-Cu-based cotton pad colorimetric strips with smartphone and utilizing color recognition software to identify and analyze the RGB values of the images, a portable colorimetric sensing platform was designed for rapid detection of aminophenol isomers without the need for any analytical instrument. This work provides an effective reference for the design of laccase nanozymes and holds significant potential for applications in the field of environmental pollutant monitoring.

Multifunctional long afterglow nanoparticles with enhanced photothermal effects for in vivo imaging and tumor-targeting therapy

Considering the excellent properties such as deep tissue penetration, high signal-to-noise ratio, and in-situ recharge and reactivation, near-infrared luminescence long afterglow nanoparticles show considerable promise for biological application, especially in multifunctional imaging, targeting, and synergistic therapeutic. In this paper, Zn3Ga4GeO11: 0.1 % Cr3+, 1 % Yb3+, 0.1 % Tm3+@Ag-FA (ZGGO@Ag-FA, ZGA-FA) nanoparticles were synthesized by in-situ growth of Ag nanoparticles on the surface of long afterglow nanoparticles, and further modified with folic acid. Through precise adjustments, the luminescent properties of ZnGa2O4 were enhanced and notably boosted the photothermal effect of Ag by leveraging the upconversion emission of ZGGO, with a photothermal conversion efficiency reaching about 59.9 %. The ZGA-FA nanoparticles are ultra-small, measuring less than 50 nm. The modification with folic acid provides the ZGA-FA nanoparticles with excellent tumor-targeting capabilities, demonstrating effective enrichment and retention in tumor tissues, thus enabling long-term imaging and therapy through in vivo re-excitation. Due to its stable photothermal effect, outstanding near-infrared (NIR) afterglow imaging, and red-light charged characteristics, combined with effective tumor-targeting abilities, the therapeutic strategy proposed by this study has significant potential for clinical applications.

Nanoparticles in drinking water: Assessing health risks and regulatory challenges

Nanoparticles (NPs) pose a significant concern in drinking water due to their potential health risks and environmental impact. This review provides a comprehensive analysis of the current understanding of NP sources and contamination in drinking water, focusing on health concerns, mitigation strategies, regulatory frameworks, and future perspectives. This review highlights the importance of nano-specific pathways, fate processes, health risks & toxicity, and the need for realistic toxicity assessments. Different NPs like titanium dioxide, silver, nanoplastics, nanoscale liquid crystal monomers, copper oxide, and others pose potential health risks through ingestion, inhalation, or dermal exposure, impacting organs and potentially leading to oxidative stress, inflammatory responses, DNA damage, cytotoxicity, disrupt intracellular energetic mechanisms, reactive oxygen species generation, respiratory and immune toxicity, and genotoxicity in humans. Utilizing case studies and literature reviews, we investigate the health risks associated with NPs in freshwater environments, emphasizing their relevance to drinking water quality. Various mitigation and treatment strategies, including filtration systems (e.g., reverse osmosis, and ultra/nano-filtration), adsorption processes, coagulation/flocculation, electrocoagulation, advanced oxidation processes, membrane distillation, and ultraviolet treatment, all of which demonstrate high removal efficiencies for NPs from drinking water. Regulatory frameworks and challenges for the production, applications, and disposal of NPs at both national and international levels are discussed, emphasizing the need for tailored regulations to address NP contamination and standardize safety testing and risk assessment practices. Looking ahead, this review underscores the necessity of advancing detection methods and nanomaterial-based treatment technologies while stressing the pivotal role of public awareness and tailored regulatory guidelines in upholding drinking water quality standards. This review emphasizes the urgency of addressing NP contamination in drinking water and provides insights into potential solutions and future research directions. Lastly, this review worth concluded with future recommendations on advanced analytical techniques and sensitive sensors for NP detection for safeguarding public health and policy implementations.

Recent advances in the construction strategy, functional properties, and biosensing application of self-assembled triangular unit-based DNA nanostructures

Research on self-assembled deoxyribonucleic acid (DNA) nanostructures with different shapes, sizes, and functions has recently made rapid progress owing to its biocompatibility, programmability, and stability. Among these, triangular unit-based DNA nanostructures, which are typically multi-arm DNA tiles, have been widely applied because of their unique structural rigidity, spatial flexibility, and cell permeability. Triangular unit-based DNA nanostructures are folded from multiple single-stranded DNA using the principle of complementary base pairing. Its shape and size can be determined using pre-set scaffold strands, segmented base complementary regions, and sequence lengths. The resulting DNA nanostructures retain the desired sequence length to serve as binding sites for other molecules and obtain satisfactory results in molecular recognition, spatial orientation, and target acquisition. Therefore, extensive research on triangular unit-based DNA nanostructures has shown that they can be used as powerful tools in the biosensing field to improve specificity, sensitivity, and accuracy. Over the past few decades, various design strategies and assembly techniques have been established to improve the stability, complexity, functionality, and practical applications of triangular unit-based DNA nanostructures in biosensing. In this review, we introduce the structural design strategies and principles of typical triangular unit-based DNA nanostructures, including triangular, tetrahedral, star, and net-shaped DNA. We then summarize the functional properties of triangular unit-based DNA nanostructures and their applications in biosensing. Finally, we critically discuss the existing challenges and future trends.

Exposure to polystyrene nanoplastics causes immune damage, oxidative stress and intestinal flora disruption in salamander (Andrias davidianus) larvae

The toxic effects of nanoparticles have been increasingly investigated, but there has been limited research on amphibians, especially those of conservation value. This study examined the effects of different concentrations (0, 0.04, 0.2, 1, 5 mg/L) of polystyrene nanoplastics (PS-NPs, 80 nm) on the short-term exposure (7 d) of Andrias davidianus. Results demonstrated the concentration-dependent enrichment of PS-NPs in the intestine. Histological lesions displayed increased hepatic macrophages with cellular rupture, broken intestinal villi, decreased cuprocytes and crypt depression. Antioxidant- and inflammation-related enzyme activities were analysed, and it was found that hepatic and intestinal MDA content and CAT activity were highest in the N-1 group and SOD activity was highest in the N-0.2 group (p < 0.05). AKP activity continued to decline, and iNOS activity was highest in the N-0.2 group (p < 0.05). il-10, tgf-β, bcl-w and txnl1 were significantly downregulated in the N-0.2 group, while il-6 and il-8 were markedly upregulated in the N-0.2 group (p < 0.05). Exposing to PS-NPs decreased probiotic bacteria (Cetobacterium, Akkermansia) and increased pathogenic bacteria (Lachnoclostridium). Our results suggest that NPs exposure can have deleterious effects on salamanders, which predicts that NPs contamination may lead to continued amphibian declines. Therefore, we strongly recommend that attention be paid to amphibians, especially endangered species, in the field of NPs.

Light-activated nanoclusters with tunable ROS for wound infection treatment

Infected wounds pose a significant clinical challenge due to bacterial resistance, recurrent infections, and impaired healing. Reactive oxygen species (ROS)-based strategies have shown promise in eradicating bacterial infections. However, the excess ROS in the infection site after treatments may cause irreversible damage to healthy tissues. To address this issue, we developed bovine serum albumin-iridium oxide nanoclusters (BSA-IrOx NCs) which enable photo-regulated ROS generation and scavenging using near infrared (NIR) laser. Upon NIR laser irradiation, BSA-IrOx NCs exhibit enhanced photodynamic therapy, destroying biofilms and killing bacteria. When the NIR laser is off, the nanoclusters' antioxidant enzyme-like activities prevent inflammation and repair damaged tissue through ROS clearance. Transcriptomic and metabolomic analyses revealed that BSA-IrOx NCs inhibit bacterial nitric oxide synthase, blocking bacterial growth and biofilm formation. Furthermore, the nanoclusters repair impaired skin by strengthening cell junctions and reducing mitochondrial damage in a fibroblast model. In vivo studies using rat infected wound models confirmed the efficacy of BSA-IrOx NCs. This study presents a promising strategy for treating biofilm-induced infected wounds by regulating the ROS microenvironment, addressing the challenges associated with current ROS-based antibacterial approaches.

Membrane electrolysis distillation for volatile fatty acids extraction from pH-neutral fermented wastewater

Volatile fatty acids (VFAs) serve as building blocks for a wide range of chemicals, but it is difficult to extract VFAs from pH-neutral wastewater using evaporation methods because of the ionized form. This study presents a new membrane electrolysis distillation (MED) process that extracts VFAs from such fermentation solutions. MED uniquely integrates pH regulation and joule heating to facilitate the efficient evaporation of VFAs. This integration occurs alongside a hydrophobic membrane that ensures effective gas-liquid phase separation. Operating solely on electricity, MED achieved an acid flux rate of 12.03 g/m2/h at 6V. In contrast, the control results without the joule heating or pH swing only obtained a 0.23 g/m2/h and 0.32 g/m2/h flux, respectively. In addition, a physicochemical model was developed to assess the impacts of temperature on membrane surface pH. This system enhances resource recovery from waste streams and helps achieve a circular carbon economy.

Machine learning-driven QSAR models for predicting the cytotoxicity of five common microplastics

In the field of microplastics (MPs) toxicity prediction, machine learning (ML) computer simulation techniques are showing great potential. In this study, six ML algorithms were utilized to predict the toxicity of MPs on BEAS-2B cells based on quantitative structure-activity relationship (QSAR) models. Comparing the models of different algorithms, the extreme gradient boosting model showed the best fit and prediction performance (R2tra = 0.9876, R2test = 0.9286). Additionally, Williams plot analysis showed that the six models developed were able to predict stably within their applicability domain, with few outliers. Finally, the three feature importance methods-Embedded Feature Importance (EFI), Recursive Feature Elimination (RFE), and SHapley Additive exPlanations (SHAP)-consistently identified particle size as the most critical feature affecting toxicity prediction. The proposed QSAR model can be utilized for preliminary environmental exposure assessments of MPs and to better understand the associated health risks.

Molecular insights reveal how the glycolipids in cell membrane mitigates nanomaterial's invasion

Nanomaterial-cellular membrane interaction is crucial for the cytotoxicity of such materials in theoretical investigations. However, previous research often used cellular membrane models with one or few lipid types, which deviates significantly from realistic membrane compositions. Here, employing molecular dynamics (MD) simulations, we investigate the impact of a typical nanomaterial, boron nitride (BN), on a cellular membrane model based on the realistic small intestinal epithelial cell (SIEC) membrane. This membrane contains a complex composition, including abundant glycolipids. Our MD simulations reveal that BN nanosheet can partially insert into the SIEC membrane, maintaining a stable binding conformation without causing obvious structural changes. Dynamic analyses suggest that van der Waals (vdW) interactions drive the binding process between BN and the SIEC membrane. Further simulation of the interaction between BN nanosheet and deglycosylated SIEC membrane confirms that BN nanosheet cause significant structural damage to deglycosylated SIEC membranes, completely inserting into the membrane, extracting lipids, and burying some lipid hydrophilic heads within the membrane interior. Quantitative analyses of mean squared displacements (MSD) of membranes, membrane thicknesses, area per lipid, and order parameters indicate that BN nanosheet causes more substantial damage to deglycosylated SIEC membrane than to intact SIEC membrane. This comparison suggests the molecular mechanism involved in mitigating BN invasion by SIEC membrane that the polysaccharide heads of glycolipids in the SIEC membrane form a significant steric hindrance on membrane surface, not only hindering the insertion of BN, but also resisting the lipid extraction by BN. Free energy calculations further support this conclusion. Overall, our MD simulations not only shed new light into the reduced impact of BN nanosheet on the realistic SIEC membrane but also highlight the importance of glycolipids in protecting cell membranes from nanomaterial invasion, contributing to a deeper understanding of nanomaterial-realistic cell membrane interactions.

An in-depth review: Unraveling the extraction, structure, bio-functionalities, target molecules, and applications of pectic polysaccharides

Pectic polysaccharides have long been a challenging subject of research in the field of macromolecular science, given their complex structures and wide range of biological effects. However, the extensive exploration of pectic polysaccharides has been limited due to the intricacy of their structures. In this comprehensive review, we aim to provide a thorough summary of the existing knowledge on pectic polysaccharides, with a particular focus on aspects such as classification, extraction methodologies, structural analysis, elucidation of biological activities, and exploration of target molecules and signaling pathways. By conducting a comprehensive analysis of existing literature and research achievements, we strive to establish a comprehensive and systematic framework that can serve as a reference and guide for further investigations into pectic polysaccharides. Furthermore, this review delves into the applications of pectic polysaccharides beyond their fundamental attributes and characteristics, exploring their potential in fields such as materials, food, and pharmaceuticals. We pay special attention to the promising opportunities for pectic polysaccharides in the pharmaceutical domain and provide an overview of related drug development research. The aim of this review is to facilitate a holistic understanding of pectic polysaccharides by incorporating multifaceted research, providing valuable insights for further in-depth investigations into this significant polymer.

Recent advances in MOF-based nanozymes: Synthesis, activities, and bioapplications

Nanozymes have garnered considerable research interest for their unique capacity to bridge nanotechnology and biology. Current studies predominantly concentrate on exploring nanozymes with diverse catalytic activities and their potential applications across various disciplines. Among them, nanoscale metal-organic frameworks (MOFs) are promising nanomaterials for constructing nanozymes. In this review, we firstly introduce the general construction strategies for MOF-based nanozymes. In addition, we also classify the MOF-based nanozymes in detail based on their catalytic performance. Thirdly, the recent research progress of MOF-based nanozymes in the field of biosensing, cancer therapy, antibacterial infection, and antioxidation are also comprehensively reviewed. Finally, we discuss the current challenges and future perspectives of MOF-based nanozymes, with the aim of assisting in their construction and maximizing their potential in bioapplications. It is hoped that we could provide scientists in materials science and biomedical research with valuable and comprehensive information, fostering advancements in interdisciplinary fields.

From challenge to opportunity: Revolutionizing the monitoring of emerging contaminants in water with advanced sensors

Emerging contaminants in water represent long-term and unpredictable threats to both environmental and human health due to their persistence and bioaccumulation. Current research predominantly focuses on their removal rather than sustained monitoring. This review comprehensively investigates advanced sensor technologies for detecting these contaminants in water, critically evaluating biosensors, optical sensors, electrochemical sensors, and nanomaterial sensors. Elucidating the operational principles, performance metrics such as detection thresholds, and the pros and cons of their practical applications, the review addresses a significant research gap in environmental monitoring. Moreover, it enhances understanding of sensor effectiveness, which in turn guides researchers in selecting the right sensor types for various environmental scenarios. Furthermore, by emphasizing the integration of nanotechnology and the standardization of evaluation protocols, it promotes the development of robust, deployable sensing solutions. Ultimately, this leads to the proposal of a strategic framework aimed at significantly improving the detection capabilities of emerging contaminants and supporting the preservation of environmental health.

New Strategies for constructing and analyzing semiconductor photosynthetic biohybrid systems based on ensemble Machine learning Models: Visualizing complex mechanisms and yield prediction

Photosynthetic biohybrid systems (PBSs) composed of semiconductor-microbial hybrids provide a novel approach for converting light into chemical energy. However, comprehending the intricate interactions between materials and microbes that lead to PBSs with high apparent quantum yields (AQY) is challenging. Machine learning holds promise in predicting these interactions. To address this issue, this study employs ensemble learning (ESL) based on Random Forest, Gradient Boosting Decision Tree, and eXtreme Gradient Boosting to predict AQY of PBSs utilizing a dataset comprising 15 influential factors. The ESL model demonstrates exceptional accuracy and interpretability (R2 value of 0.927), offering insights into the impact of these factors on AQY while facilitating the selection of efficient semiconductors. Furthermore, this research propose that efficient charge carrier separation and transfer at the bio-abiotic interface are crucial for achieving high AQY levels. This research provides guidance for selecting semiconductors suitable for productive PBSs while elucidating mechanisms underlying their enhanced efficiency.

A pentavalent peptide vaccine elicits Aβ and tau antibodies with prophylactic activity in an Alzheimer's disease mouse model

Amyloid-β (Aβ) and hyperphosphorylated tau protein are targets for Alzheimer's Disease (AD) immunotherapies, which are generally focused on single epitopes within Aβ or tau. However, due to the complexity of both Aβ and tau in AD pathogenesis, a multipronged approach simultaneously targeting multiple epitopes of both proteins could overcome limitations of monotherapies. Herein, we propose an active AD immunotherapy based on a nanoparticle vaccine comprising two Aβ peptides (1-14 and pyroglutamate pE3-14) and three tau peptides (centered on phosphorylated pT181, pT217 and pS396/404). These correspond to both soluble and aggregated targets and are displayed on the surface of immunogenic liposomes in an orientation that maintains reactivity with epitope-specific monoclonal antibodies. Intramuscular immunization of mice with individual epitopes resulted in minimally cross-reactive antibody induction, while simultaneous co-display of 5 antigens ("5-plex") induced antibodies against all epitopes without immune interference. Post-immune sera recognized plaques and neurofibrillary tangles from human AD brain tissue. Vaccine administration to 3xTg-AD mice using a prophylactic dosing schedule inhibited tau and amyloid pathologies and resulted in improved cognitive function. Immunization was well tolerated and did not induce antigen-specific cellular responses or persistent inflammatory responses in the peripheral or central nervous system. Antibody levels could be reversed by halting monthly vaccinations. Altogether, these results indicate that active immune therapies based on nanoparticle formulations of multiple Aβ and tau epitopes warrant further study for treating early-stage AD.

Low defect density in MoS2 monolayers grown on Au(111) by metal-organic chemical vapor deposition

Monolayers of transition metal dichalcogenides (TMDs) possess high potential for applications in novel electronic and optoelectronic devices and therefore the development of methods for their scalable growth is of high importance. Among different suggested approaches, metal-organic chemical vapor deposition (MOCVD) is the most promising one for technological applications because of its lower growth temperature compared to the most other methods, e.g., conventional chemical vapor or atomic layer deposition (CVD, ALD). Here we demonstrate for the first time the epitaxial growth of MoS2 monolayers on Au(111) by MOCVD at 450 °C. We confirm the high quality of the grown TMD monolayers down to the atomic scale using several complementary methods. These include Raman spectroscopy, non-contact atomic force microscopy (nc-AFM), X-ray photoelectron spectroscopy and scanning tunneling microscopy (STM). The topographic corrugation of the MoS2 monolayer on Au(111), revealed in a moiré structure, was measured as ≈20 pm by nc-AFM. The estimated defect density calculated from STM images of the as-grown MoS2 monolayers is in the order of 1012 vacancies/cm2. The defects are mainly caused by single sulfur vacancies. Our approach is a step forward towards the technologically relevant growth of high-quality, large-area TMD monolayers.

Anthraquinones-based photocatalysis: A comprehensive review

In recent years, there has been significant interest in photocatalytic technologies utilizing semiconductors and photosensitizers responsive to solar light, owing to their potential for energy and environmental applications. Current efforts are focused on enhancing existing photocatalysts and developing new ones tailored for environmental uses. Anthraquinones (AQs) serve as redox-active electron transfer mediators and photochemically active organic photosensitizers, effectively addressing common issues such as low light utilization and carrier separation efficiency found in conventional semiconductors. AQs offer advantages such as abundant raw materials, controlled preparation, excellent electron transfer capabilities, and photosensitivity, with applications spanning the energy, medical, and environmental sectors. Despite their utility, comprehensive reviews on AQs-based photocatalytic systems in environmental contexts are lacking. In this review, we thoroughly describe the photochemical properties of AQs and their potential applications in photocatalysis, particularly in addressing key environmental challenges like clean energy production, antibacterial action, and pollutant degradation. However, AQs face limitations in practical photocatalytic applications due to their low electrical conductivity and solubility-related secondary contamination. To mitigate these issues, the design and synthesis of graphene-immobilized AQs are highlighted as a solution to enhance practical photocatalytic applications. Additionally, future research directions are proposed to deepen the understanding of AQs' theoretical mechanisms and to provide practical applications for wastewater treatment. This review aims to facilitate mechanistic studies and practical applications of AQs-based photocatalytic technologies and to improve understanding of these technologies.

Surface nanocoating-based universal platform for programmed delivery of microorganisms in complicated digestive tract

Microbial therapies have promising applications in the treatment of a broad range of diseases. However, effective colonization of the target region by therapeutic microorganisms remains a significant challenge owing to the complexity of the intestinal system. Here, we developed surface nanocoating-based universal platform (SNUP), which enabled the manipulation of controlled release and targeted colonization of therapeutic microbes in the digestive tract without the utilization of any targeting molecules. The system controlled the decomposition time of SNUP in the gut by regulating different modification layers and modification sequences on the microorganism's surface, so that the microorganism was released at a predetermined time and space. With the SNUP nanomodification technology, we could effectively deliver therapeutic microorganisms to specific complex intestinal regions such as the small intestine and colon, and protect the bioactivity of therapeutic microorganisms from destruction by both strong acids and digestive enzymes. In this study, we found that two layers SNUP-encapsulated Liiliilactobacillus salivarius (LS@CCMC) could efficiently colonize the small intestine and significantly improve the symptoms of a mouse model of Parkinson's disease through sustained secretion of γ-aminobutyric acid (GABA). This surface nanocoating-based universal platform system does not require the design of specific targeting molecules, providing a simple and universal method for colonized microbial therapy, target theranostics, precision medicine, and personalized medicine.

Enhancing reliability for AFB1 analysis in food: Ratiometric fluorescence/colorimetric dual-modal analysis platform using multifunctional GO-Fe3O4

Adsorption of DNA fluorescent probes on GO-Fe3O4 is a promising strategy for establishing fluorescent bioassays, often using magnetic separation or fluorescence quenching to generate signals. However, there is a lack of systematic understanding of ssDNA-regulated changes in the enzyme-mimetic activity of GO-Fe3O4, and the accuracy of the results of single-mode fluorescence analysis is susceptible to environmental interference. These limit the rational design and scope of application of the methods. Herein, the force and the catalytic mechanism of ssDNA/GO-Fe3O4 interactions were explored in detail. On this basis, a ratiometric fluorescence/colorimetric dual-modal analysis platform was constructed based on the superparamagnetism and DNA controllable peroxidase-like activity of GO-Fe3O4. The ratiometric fluorescent signal was generated by combining 7-amino-4-methyl-3-coumarinylacetic acid (AMCA) labeled aptamer (AMCA-aptamer) with AT hairpin-synthesized copper nanoparticles, which has built-in correction and resistance to environmental interference. The aptamer-modulated peroxidase-like activity of GO-Fe3O4 generated the colorimetric signal. Two signals correct each other to further enhance the reliability of the results. The analytical platform performed satisfactorily for AFB1 detection in the range of 0.1-150 μg/L, and was successfully applied to real samples (peanut, milk powder, and wheat flour). With the support of ImageJ software, quantitative detection was achieved by RGB channel analysis for real-color images, which provides a potential pathway for the rapid detection of food safety.

Derivative spectrophotometry-assisted determination of tryptophan metabolites emerges host and intestinal flora dysregulations during sepsis

Sepsis is a life-threatening condition characterized by organ dysfunction resulting from a dysregulated host response to infection. Dysregulated tryptophan (TRP) metabolites serve as significant indicators for endogenous immune turnovers and abnormal metabolism in the intestinal microbiota during sepsis. Therefore, a high coverage determination of TRP and its metabolites in sepsis is beneficial for the diagnosis and prognosis of sepsis, as well as for understanding the underlying mechanism of sepsis development. However, similar structures in TRP metabolites make it challenging for separation and metabolite identification. Here, high-performance liquid chromatography coupled with a diode array detector (HPLC-DAD) was developed to determine TRP metabolites in rat serum. The first-order derivative spectrophotometry of targeted metabolites in the serum was investigated and proved to be promising for chromatographic peak annotation across different columns and systems. The established method separating the targeted metabolites was optimized and validated to be sensitive and accurate. Application of the method revealed dysregulated TRP metabolites, associated with immune disorders and NAD + metabolism in both the host and gut flora in septic rats. Our findings indicate that the derivative spectrophotometry-assisted method enhances metabolite identifications for the chromatographic systems based on DAD detectors and holds promise for precision medicine in sepsis.

Characterization of extended defects in 2D materials using aperture-based dark-field STEM in SEM

Quantitative diffraction contrast analysis with defined diffraction vectors is a well-established method in TEM for studying defects in crystalline materials. A comparable transmission technique is however not available in the more widely used SEM platforms. In this work, we transfer the aperture-based dark-field imaging method from the TEM to the SEM, thus enabling quantitative diffraction contrast studies at lower voltages in SEM. This is achieved in STEM mode by inserting a custom-made aperture between the sample and the STEM detector and centering the hole on a desired reflection. To select individual reflections for dark-field imaging, we use our Low Energy Nanodiffraction (LEND) setup [Schweizer et al., Ultramicroscopy 213, 112956 (2020)], which captures transmission diffraction patterns from a fluorescent screen positioned below the sample. The aperture-based dark-field STEM method is particularly useful for studying extended defects in 2D materials, where (i) stronger diffraction at the lower voltages used in SEM is advantageous, but (ii) two-beam conditions cannot be established, making quantitative diffraction contrast analysis with standard bright-field and annular dark-field detectors impossible. We demonstrate the method by studying basal plane dislocations in bilayer graphene, which have attracted considerable research interest due to their exceptional structural and electronic properties. Direct comparison of results obtained on identical dislocations by the established TEM method and by the new aperture-based dark-field STEM method in SEM shows that a reliable Burgers vector analysis is possible by applying the well-known g·b=0 invisibility criterion. We further use the LEND setup to acquire 4D-STEM data and show that the virtual dark-field images match well with those in aperture-based dark-field STEM images for reliable Burgers vector analysis.

Development of biomass aerogels with aligned channels: For continuous treatment of oily wastewater and solar-powered oil evaporation

A biomass CS/CNTs@MTMS (MCCS) aerogel with both aligned channel network, superhydrophobicity, and photothermal conversion ability was prepared by a green and facile strategy of directed freeze-drying and chemical vapor deposition using chitosan (CS), carbon nanotubes (CNTs), and methyltrimethoxysilane (MTMS) as the building materials. Capacity to adsorb a large variety of oils and organic solvents, with an adsorption capacity of up to 34-83 g/g. After 10 cycles, the adsorption capacity of MCCS remained at 94 % of the initial capacity, providing excellent reusability. In addition, due to its unique network of aligned channels, the MCCS can continuously separate oil and water, making it a sustainable oil-water separator. More interestingly, the MCCS aerogel has excellent photothermal conversion capabilities, and it was utilized to evaporate oil collected during the oil-water separation process using solar energy. This work provides an opportunity to design novel self-cleaning photothermally driven oil-water separation biomass materials with superhydrophobicity-strong lipophilicity.

Combining hybrid cell membrane modified magnetic nanoparticles and inverted microfluidic chip for in situ CTCs capture and inactivation

Circulating tumor cells (CTCs) serve as crucial indicators for tumor occurrence, progression, and prognosis monitoring. However, achieving high sensitivity and high purity capture of CTCs remains challenging. Additionally, in situ capture and synchronous clearance hold promise as methods to impede tumor metastasis, but further exploration is needed. In this study, biomimetic cell membrane-coated magnetic nanoparticles (NPs) were designed to address the issue of nonspecific adsorption of capture probes by the immune system during blood circulation. Membranes from human breast cancer cells (tumor cell membranes, TMs) and leukocytes (white blood cell membranes, WMs) were extracted and fused to form a hybrid membrane (HM), which was further modified onto the surface of porous magnetic NPs loaded with indocyanine green (ICG). The incorporation of TM enhanced the material's target specificity, thus increasing capture efficiency, while WM coating reduced interference from homologous white blood cells (WBCs), further enhancing capture purity. Additionally, in conjunction with our novel inverted microfluidic chip, this work introduces the first use of polymer photonic crystals as the capture interface for CTCs. Besides providing an advantageous surface structure for CTC attachment, the 808 nm photonic bandgap effectively amplifies the 808 nm excitation light at the capture surface position. Therefore, upon capturing CTCs, the ICG molecules in the probes facilitate enhanced photothermal (PTT) and photodynamic (PDT) synergistic effects, directly inactivating the captured CTCs. This method achieves capture efficiency and purity exceeding 95% and permits in situ inactivation post-capture, providing an important approach for future research on impeding tumor metastasis in vivo.

Camptothecin multifunctional nanoparticles effectively achieve a balance between the efficacy of breast cancer treatment and the preservation of intestinal homeostasis

Camptothecin (CPT) exhibits potent antitumor activity; however, its clinical application is limited by significant gastrointestinal adverse effects (GAEs). Although the severity of GAEs associated with CPT derivatives has decreased, the incidence rate of these adverse effects has remained high. CPT multifunctional nanoparticles (PCRHNs) have the potential to increase the efficacy of CPT while reducing side effects in major target organs; however, the impact of PCRHNs on the GAEs from CPT remains uncertain. Here, we investigated the therapeutic effects of PCRHNs and different doses of CPT and examined their impacts on the intestinal barrier and the intestinal microbiota. We found that the therapeutic efficacy of PCRHNs + Laser treatment was superior to that of high-dose CPT, and PCRHNs + Laser treatment also provided greater benefits by helping maintain intestinal barrier integrity, intestinal microbiota diversity, and intestinal microbiota abundance. In summary, compared to high-dose CPT treatment, PCRHNs + Laser treatment can effectively balance therapeutic effects and GAEs. A high dose of CPT promotes the enrichment of the pathogenic bacteria Escherichia-Shigella, which may be attributed to diarrhea caused by CPT, thus leading to a reduction in microbial burden; additionally, Escherichia-Shigella rapidly grows and occupies niches previously occupied by other bacteria that are lost due to diarrhea. PCRHNs + Laser treatment increased the abundance of Lactobacillus (probiotics), possibly due to the photothermal effect of the PCRHNs. This effect increased catalase activity, thus facilitating the conversion of hydrogen peroxide into oxygen within tumors and increasing oxygen levels in the body, which is conducive to the growth of facultative anaerobic bacteria.

Microplastic accumulation and oxidative stress in sweet pepper (Capsicum annuum Linn.): Role of the size effect

Microplastics (MPs), which are widely dispersed in terrestrial environments, threaten crop growth and human food security. However, plant accumulation and phytotoxicity related to the size effects of MPs remain insufficiently explored. This study investigated the accumulation and toxicity of two sizes of MPs on Capsicum annuum Linn. (C. annuum) through fluorescence tracing and antioxidant defense system assessment. The results revealed that the size of MPs significantly impacts their accumulation characteristics in C. annuum roots, leading to variations in toxic mechanisms, including oxidative stress and damage. Smaller MPs and higher exposure concentrations result in more pronounced growth inhibition. C. annuum roots have a critical size threshold for the absorption of MPs of approximately 1.2 μm. MPs that enter the root tissue exhibit an aggregated form, with smaller-sized MPs displaying a greater degree of aggregation. MP exposure induces oxidative stress in root tissues, with high concentrations of smaller MPs causing lipid peroxidation. Analysis of the IBR values revealed that C. annuum roots utilize ascorbic acid (ASA) to prevent oxidative damage caused by larger MPs. Conversely, smaller MPs primarily induce superoxide dismutase (SOD) and glutathione (GSH). These results emphasize the significant impact of MP size on plant antioxidant defense response mechanisms, laying the foundation for further investigating the implications for human health.

Engineered nanovesicles mediated cardiomyocyte survival and neovascularization for the therapy of myocardial infarction

Myocardial infarction (MI) leads to substantial cellular necrosis as a consequence of reduced blood flow and oxygen deprivation. Stimulating cardiomyocyte proliferation and angiogenesis can promote functional recovery after cardiac events. In this study, we explored a novel therapeutic strategy for MI by synthesizing a biomimetic nanovesicle (NV). This biomimetic NVs are composed of exosomes sourced from umbilical cord mesenchymal stem cells, which have been loaded with placental growth factors (PLGF) and surface-engineered with a cardiac-targeting peptide (CHP) through covalent bonding, termed Exo-P-C NVs. With the help of the myocardial targeting effect of homing peptides, NVs can be enriched in the MI site, thus improve cardiac regeneration, reduce fibrosis, stimulate cardiomyocyte proliferation, and promote angiogenesis, ultimately resulted in improved cardiac functional recovery. It was demonstrated that Exo-P-C NVs have the potential to offer novel therapeutic strategies for the improvement of cardiac function and management of myocardial infarction.

Colorimetric sensor array for identifying antioxidants based on pyrolysis-free synthesis of Fe-N/C single-atom nanozymes

Iron-anchored nitrogen/doped carbon single-atom nanozymes (Fe-N/C), which possess homogeneous active sites and adjustable catalytic environment, represent an exemplary model for investigating the structure-function relationship and catalytic activity. However, the development of pyrolysis-free synthesis technique for Fe-N/C with adjustable enzyme-mimicking activity still presents a significant challenge. Herein, Fe-N/C anchored three carrier morphologies were created via a pyrolysis-free approach by covalent organic polymers. The peroxidase-like activity of these Fe-N/C nanozymes was regulated via the pores of the anchored carrier, resulting in varying electron transfer efficiency due to disparities in contact efficacy between substrates and catalytic sites within diverse microenvironments. Additionally, a colorimetric sensor array for identifying antioxidants was developed: (1) the Fe-N/C catalytically oxidized two substrates TMB and ABTS, respectively; (2) the development of a colorimetric sensor array utilizing oxTMB and oxABTS as sensing channels enabled accurate discrimination of antioxidants such as ascorbic acid (AsA), glutathione (GSH), cysteine (Cys), gallic acid (GA), and caffeic acid (CA). Subsequently, the sensor array underwent rigorous testing to validate its performance, including assessment of antioxidant mixtures and individual antioxidants at varying concentrations, as well as target antioxidants and interfering substances. In general, the present study offered valuable insights into the active origin and rational design of nanozyme materials, and highlighting their potential applications in food analysis.

Colorimetric aptasensor based on self-screened aptamers and cascaded catalytic reaction for the detection of quarantine plant bacteria

Quarantine plant bacteria (QPB) are significant component of invasive alien species that result in substantial economic losses and serious environmental damage. Herein, a colorimetric aptasensor has been proposed based on the sandwich structure and the cascaded catalytic strategy for on-site detecting Xanthomonas hyacinthi, a type of QPB, in natural environments. The self-screened aptamer obtained through SELEX can bind to specific sites on the surface of viable organism with high affinity and specificity, which guarantees the selectivity of aptasensor. As an important part of the aptasensor, MIL-88-NH2(Fe) not only acts as a multifunctional carrier for both aptamers and glucose oxidase, but also catalyzes enzyme-like reaction because of specific surface area, amino and peroxidase-like activity. The present of Xanthomonas hyacinthi can trigger the formation of a sandwich structure and the occurrence of cascade catalytic reaction, enabling the detection with UV-Vis spectra and naked eyes. The proposed aptasensor presents a low detection limit of 2 cfu/mL and a wide linear range of 10 -107 cfu/mL. Compared to traditional detection methods for QPB, the reasonable design, high selectivity and convenience significantly improve the detection efficiency and contribute to environmental protection.

Variable-transmittance bio-based phase change composites based on the photothermal property of pectin

In this study, the possibility of using a natural polysaccharide, pectin, in a novel function as a photothermal material was investigated by fabricating a Pectin/Polyethylene glycol (PEG)/Poly(methyl methacrylate) (PMMA) composite via the infiltration of PEG/PMMA polymer mixture into freeze-casted pectin cryogel template. The Pectin/PEG/PMMA composite has high latent heat of 48 J/g, excellent UV blocking ability, and tailorable transmittance as well as capacity to energy storage via photothermal heating to the melting point of PEG under sunlight. The photothermal effect can be enhanced with the increase of pectin concentration and irradiation intensity. Furthermore, by using the Pectin/PEG/PMMA composite as a window of a model house could effectively reduce the temperature rise inside the house under irradiation and reduce the temperature drop after turning off the irradiation, as compared to a model house with conventional glass as the window material. Therefore, this work provides a new application of pectin as photothermal material and opens the opportunity to develop novel sustainable bio-based photothermal materials.

Optimizing UVA and UVC synergy for effective control of harmful cyanobacterial blooms

Harmful cyanobacterial blooms (HCBs) pose a global ecological threat. Ultraviolet C (UVC) irradiation at 254 nm is a promising method for controlling cyanobacterial proliferation, but the growth suppression is temporary. Resuscitation remains a challenge with UVC application, necessitating alternative strategies for lethal effects. Here, we show synergistic inhibition of Microcystis aeruginosa using ultraviolet A (UVA) pre-irradiation before UVC. We find that low-dosage UVA pre-irradiation (1.5 J cm-2) combined with UVC (0.085 J cm-2) reduces 85% more cell densities compared to UVC alone (0.085 J cm-2) and triggers mazEF-mediated regulated cell death (RCD), which led to cell lysis, while high-dosage UVA pre-irradiations (7.5 and 14.7 J cm-2) increase cell densities by 75-155%. Our oxygen evolution tests and transcriptomic analysis indicate that UVA pre-irradiation damages photosystem I (PSI) and, when combined with UVC-induced PSII damage, synergistically inhibits photosynthesis. However, higher UVA dosages activate the SOS response, facilitating the repair of UVC-induced DNA damage. This study highlights the impact of UVA pre-irradiation on UVC suppression of cyanobacteria and proposes a practical strategy for improved HCBs control.

Construction of portable hydrogel kits with self-ratio optical bimodal detection and smartphone imaging for on-site nitrite screening

Accurate on-site detection of nitrite in complex matrices remains a significant challenge. Herin, we construct a self-ratio optical bimodal portable kit via co-assembling NaErF4:0.5%Tm@NaYF4@NaYbF4:0.5%Tm@NaYF4 (Er:Tm@Yb:Tm) and nitrogen-doped carbon platinum nanomaterials (Pt/CN) in sodium alginate (SA) hydrogel. Pt/CN nanomaterials are synthesized by high-temperature sintering using a zinc-based zeolite imidazolium framework as a sacrificial template. The Pt/CN nanozyme possesses excellent oxidase-like activity to produce the oxidation state 3,3',5,5'-tetramethylbenzidine (oxTMB). Nitrite mediates diazotization of oxTMB to trigger the change of absorption signals, accompanying the ratio fluorescence response of the Er:Tm@Yb:Tm. Crucially, Er:Tm@Yb:Tm and Pt/CN are embedded in SA hydrogel to fabricate a portable kit with efficient and sensitive performance. An image processing algorithm is used to analyze the nitrite-induced signal change of the portable hydrogel kit, resulting in detection limits of 0.63 μM. This method has great potential for point-of-care applications due to its reliability, long-term stability, accuracy, sensitivity, and portability.

Multi-laser nanoparticle tracking analysis (NTA): A unique method to visualize dynamic (shear) and dynamic (Brownian motion) light scattering and quantify nonliving natural organic matter (NNOM) in environmental water

Application of simultaneous multi-laser nanoparticle tracking analysis (NTA) to environmental water samples to investigate nonliving natural organic matter (NNOM) is introduced as an innovative method for observing particles directly in their native media. Multi-laser NTA results of particle visualization, particle number concentration, and particle size distribution elucidated particle dynamics in low and high total dissolved solids (TDS) aqueous environmental samples. A pond water sample and concentrate from a reverse osmosis (RO) treatment process (Stage 1) had 1.3 × 108 and 5.62 × 1019 particles/mL, respectively, (at time = 0) after filtration at 0.45 μm. Beyond the traditional applications for this instrument, this research presents novel evidence-based investigations that probe the existence of supramolecular structures in environmental waters during turbulence or quiescence. The pond water sample exhibited time-dependent aggregation as the volume distribution shifted to greater diameter during quiescence, compared to turbulence. Disaggregation (increased numbers of particles over time) was noted in the >250 nm to <600 nm region, and aggregation of >450 nm particles was also noted in the quiescent RO concentrate sample, indicative of depletion of small particles to form larger ones. Multi-laser NTA and dynamic light scattering (DLS) capabilities were compared and contrasted. DLS and NTA are different (complementary) particle sizing techniques. DLS yielded more information about the physical hydrogel in the NNOM hierarchy whereas multi-laser NTA better characterized meta-chemical and chemical hydrogel characteristics. Operationalization of innovation-moving from fundamental investigations to application-is supported by implementing novel analytical instrumentation as we address issues involving climate change, drought, and the scarcity of potable water. Multi-laser NTA can be used as a tool to study and optimize complex water and wastewater treatment processes. Questions about water treatment efficiencies, membrane fouling, assistance of pollutant transport, and carbon capture cycles affected by NNOM will benefit from insights from multi-laser NTA.

Introducing high-performance star-shaped bimetallic nanotags into SERS aptasensor: An ultrasensitive and interference-free method for chlorpyrifos detection

Implementation of cost-effective, reliable, and efficient technologies for the sensitive, rapid, and accurate detection of pesticide residues in agriproducts presents a promising solution to the escalating food safety concerns. Herein, a high-performance surface-enhanced Raman scattering (SERS) aptasensor based on nanotag (AuNS@4-MBN@Ag-aptamer) was introduced for ultrasensitive, reliable, and interference-free detection of chlorpyrifos (CPF). This aptasensor featured star-shaped bimetallic nanotag as the principal Raman signal enhancement material and 4-mercaptobenzonitrile (4-MBN) as "biological-silent"-window reporter (at 2228 cm-1). Moreover, cDNA-linked Fe3O4@AuNPs (FA-cDNA) served as magnetic substrates to simplify the separation process of FA-cDNA-combined nanotags. In the aptasensor, the formation of FA-cDNA-aptamer-AuNS@4-MBN@Ag hybrids was hindered by CPF, and its Raman intensity decreased with increasing CPF concentration. Under optimal SERS conditions, the aptasensor exhibited a broad linear detection range from 2.5 × 102 to 5.0 × 104 pg⋅mL-1, with an impressively low limit of detection of 220.35 pg⋅mL-1 (signal-to-noise ratio = 3). The selectivity and reproducibility assessments highlighted its exceptional sensitivity and interference-free capabilities. Furthermore, practical applications on wheat and apples demonstrated satisfactory spiked recovery rates, ranging from 89.61% to 107.33% (relative standard deviation ≤ 14.55%). Consequently, the high-performance "biological-silent"-window nanotag-based aptasensor is a promising tool for monitoring trace CPF in complex matrices.

Nanozyme-based colorimetric sensor arrays coupling with smartphone for discrimination and "segmentation-extraction-regression" deep learning assisted quantification of flavonoids

Achieving rapid, cost effective, and intelligent identification and quantification of flavonoids is challenging. For fast and uncomplicated flavonoid determination, a sensing platform of smartphone-coupled colorimetric sensor arrays (electronic noses) was developed, relying on the differential competitive inhibition of hesperidin, nobiletin, and tangeretin on the oxidation reactions of nanozymes with a 3,3',5,5'-tetramethylbenzidine substrate. First, density functional theory calculations predicted the enhanced peroxidase-like activities of CeO2 nanozymes after doping with Mn, Co, and Fe, which was then confirmed by experiments. The self-designed mobile application, Quick Viewer, enabled a rapid evaluation of the red, green, and blue values of colorimetric images using a multi-hole parallel acquisition strategy. The sensor array based on three channels of CeMn, CeFe, and CeCo was able to discriminate between different flavonoids from various categories, concentrations, mixtures, and the various storage durations of flavonoid-rich Citri Reticulatae Pericarpium through a linear discriminant analysis. Furthermore, the integration of a "segmentation-extraction-regression" deep learning algorithm enabled single-hole images to be obtained by segmenting from a 3 × 4 sensing array to augment the featured information of array images. The MobileNetV3-small neural network was trained on 37,488 single-well images and achieved an excellent predictive capability for flavonoid concentrations (R2 = 0.97). Finally, MobileNetV3-small was integrated into a smartphone as an application (Intelligent Analysis Master), to achieve the one-click output of three concentrations. This study developed an innovative approach for the qualitative and simultaneous multi-ingredient quantitative analysis of flavonoids.

Fabrication, characterization, and bioactivity of self-assembled carrier-free colloidal dispersions from Citrus × Limon 'Rosso' essential oil and tea polyphenols

Carrier-free nanodelivery systems are fully self-assembled from active ingredients through interactions, offering the advantages of green, safe, and large-scale manufacturing. To improve the dispersion of Citrus × limon 'Rosso' peel essential oil (CEO) in water and boost the biological activity of CEO and tea polyphenols (TP), self-assembled CEO-TP colloidal dispersions (CEO-TP Colloids) were fabricated through sonication without surfactants or carriers. The optimal CEO and TP concentrations in the CEO-TP Colloids were determined to be 10.0 and 20.0 mg/mL by particle size and stability analyzer, respectively. The CEO self-assembled with TP to form spherical nanoparticles through hydrophobic and hydrogen-bonding interactions, whereas the CEO in CEO-TP Colloids weakened TP intramolecular aggregation. Meanwhile, the CEO-TP Colloids showed synergistic effects with better antibacterial, cellular antioxidant, and anti-inflammatory activities than single components. This study opens up the possibility of carrier-free co-delivery of hydrophobic and hydrophilic active components developed into food-grade formulations with multiple bioactivities.

Directional regulation of reactive oxygen species in titanium dioxide boosting the photocatalytic degradation performance of azo dyes

It has been widely accepted that the generation of reactive oxygen species such as superoxide radical, hydroxyl radical, and hydrogen peroxide during photocatalysis is responsible for the degradation of azo dyes. However, it is unclear which reactive oxygen species primarily contributes to the degradation efficiency of azo dyes. Here, we demonstrate that the directional regulation of reactive oxygen species in titanium dioxide (TiO2) to form superoxide radicals by ethylenediaminetetraacetic acid disodium salt (EDTA-2Na) can significantly improve the degradation performance of methyl orange. The optimized addition of EDTA-2Na can completely degrade azo dyes such as methyl orange, acid orange and alkaline orange at a concentration of 10 mg/L in about 20 min, which is not only higher than that achieved by pristine TiO2 under Xe lamp light but also far superior to the reported degradation efficiency of modified TiO2. Even under natural sunlight, this strategy can also effectively decompose azo dyes, demonstrating the great potential for practical water treatment using low-cost TiO2 photocatalysts.

CoS2/carbon network flexible film with Co-N bond/π-π interaction enables superior mechanical properties and high-rate sodium ion storage

Flexible electrodes based on conversion-type materials have potential applications in low-cost and high-performance flexible sodium-ion batteries (FSIBs), owing to their high theoretical capacity and appropriate sodiation potential. However, they suffer from flexible electrodes with poor mechanical properties and sluggish reaction kinetics. In this study, freestanding CoS2 nanoparticles coupled with graphene oxides and carbon nanotubes (CoS2/GO/CNTs) flexible films with robust and interconnected architectures were successfully synthesized. CoS2/GO/CNTs flexible film displays high electronic conductivity and superior mechanical properties (average tensile strength of 21.27 MPa and average toughness of 393.18 KJ m-3) owing to the defect bridge for electron transfer and the formation of the π-π interactions between CNTs and GO. In addition, the close contact between the CoS2 nanoparticles and carbon networks enabled by the Co-N chemical bond prevents the self-aggregation of the CoS2 nanoparticles. As a result, the CoS2/GO/CNTs flexible film delivered superior rate capability (213.5 mAh g-1 at 6 A g-1, better than most reported flexible anode) and long-term cycling stability. Moreover, the conversion reaction that occurred in the CoS2/GO/CNTs flexible film exhibited pseudocapacitive behavior. This study provides meaningful insights into the development of flexible electrodes with superior mechanical properties and electrochemical performance for energy storage.