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Although silver is widely added to various chronic wounds to kill higher concentrations (107–108 CFU mL−1) of bacteria, overdose of silver remains a major cause of diverse side effects, such as cytotoxicity and tissue and organ damage. Here we showed that reducing the dose level of silver, additionally conferring electron transfer potential, could simultaneously achieve good biocompatibility and strong bactericidal ability without introducing extra chemical residuals for chronic wound treatment. A systematic investigation demonstrated that 1 ppm trivalent silver ions performed rapid (5 min) and effective antibacterial activities against pathogens while not significantly affecting cell viability which were equivalent to 20 ppm monovalent silver ions with cytotoxicity, and accelerated the healing process and improved the tissue quality of burn wounds. The killing effect is independent of material and is mainly controlled by the electron transfer potentials of trivalent silver ions, which disrupts the electron transport of bacteria membrane respiration and leads to the death of bacteria. Together, such trivalent silver opens up new possibilities for dispelling the concern of silver usage in biosafety and provides an avenue for designing antibiotics or other biomedical applications. [ABSTRACT FROM AUTHOR]

We present generalizing statistical surrogate models to select an optimized photosensitizer, TPP, which is subsequently loaded into autologous exosomes by ultrasonic mixing to achieve tumor targeting with enhanced therapeutic efficacy by photodynamic therapy (PDT). This work contributes to the exploration of PDT enhancement strategies, and provides new prospects for using autologous exosomes as a delivery system.

Cantharidin (CTD) has been widely used to treat hepatocellular carcinoma (HCC) in clinical practice. However, the current CTD preparations may induce hepatic and renal damage due to their non-specific distribution. Therefore, redox-sensitive polymer Pluronic F127-disulfide bond-poly(d,l-lactide) (F127-SS-PDLA) and active targeting polymer F127-glycyrrhetinic acid (F127-GA) were synthesized to prepare mixed micelles (GA/F127-SS-PDLA/CTD) for effective delivery of CTD. Fourier transform infrared (FTIR) spectroscopy and 1 H nuclear magnetic resonance ( 1 H-NMR) spectroscopy were used to verify the successful synthesis of F127-SS-PDLA and F127-GA. During the preparation, this study was the first to screen the density of GA by cellular uptake assay. The results indicated that mixed micelles with 10% and 15% F127-GA (weight fraction) exhibited superior cellular uptake in comparison to micelles with 5% and 20% F127-GA. GA/F127-SS-PDLA/CTD micelles prepared by thin film hydration method demonstrated excellent drug loading capacity for CTD (16.12 ± 0.11%). The particle size and zeta potential of GA/F127-SS-PDLA/CTD micelles were 85.17 ± 1.24 nm and -11.71 ± 0.86 mV, respectively. Hemolysis and stability assay showed that the mixed micelles had good blood compatibility and could remain stable for 30 days at 4 °C. The redox-sensitivity of GA/F127-SS-PDLA/CTD micelles in vitro was verified under reducing conditions through dynamic light scattering (DLS) and an in vitro drug release experiment, which showed obvious particle size variation and rapid drug release ability. In cellular experiments, GA/F127-SS-PDLA/CTD micelles could induce superior cytotoxicity, apoptosis and intracellular reactive oxygen species (ROS) levels compared with free CTD, non-sensitive F127-PDLA/CTD micelles and redox-sensitive F127-SS-PDLA/CTD micelles. The cellular uptake ability of nile red-labeled GA/F127-SS-PDLA micelles, which was evaluated via fluorescent microscope and flow cytometry, indicated that the modification of GA significantly increased micelle uptake in HepG-2 cells. Consequently, GA/F127-SS-PDLA/CTD micelles could be considered as a satisfactory drug administration strategy in the treatment of HCC., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

As a unique structural form, helical structures have a wide range of application prospects. In the field of biology, helical structures are essential for the function of biological macromolecules such as proteins, so the study of helical structures can help to deeply understand life phenomena and develop new biotechnology. In materials science, helical structures can give rise to special physical and chemical properties, such as in the case of spiral nanotubes, helical fibers, etc. , which are expected to be used in energy, environment, medical and other fields. The helical structure also has unique charm and application value in the fields of aesthetics and architecture. In addition, helical fibers have attracted a lot of attention because of their tendrils' vascular geometry and indispensable structural properties. In this paper, the development of helical fibers is briefly reviewed from the aspects of mechanism, synthesis process and application. Due to their good chemical and physical properties, helical fibers have a good application prospect in many fields. Potential problems and future opportunities for helical fibers are also presented for future studies.

Layered silicon (L-Si) anodes are celebrated for their high theoretical capacity but face significant challenges regarding safety and material purity during preparation. This study addresses these challenges by employing NH 4 Cl-CaSi 2 as the raw material in a gas-solid de-alloying process, which enhances both safety and purity compared to traditional methods. The L-Si anodes produced demonstrate outstanding electrochemical performance, delivering a high reversible lithium storage capacity of 1497.7 mA h g -1 at a current density of 0.5 A g -1 , and exhibiting stable performance over 1200 charge-discharge cycles. In situ and ex situ characterizations reveal that electrolyte decomposition products effectively fill the voids within the electrode, while the gradual disintegration of the L-Si structure contributes to the formation of a dense, conductive network. This process enhances lithium ion transport and exploits the capacitive storage benefits of layered silicon.

The application of nanotechnology in antifungal therapy is gaining increasing attention. Current antifungal drugs have significant limitations, such as severe side effects, low bioavailability, and the rapid development of resistance. Nanotechnology offers an innovative solution to address these issues. This review discusses three key strategies of nanotechnology to enhance antifungal efficacy. Firstly, nanomaterials can enhance their interaction with fungal cells via ingenious surface tailoring of nanomaterials. Effective adhesion of nanoparticles to fungal cells can be achieved by electrostatic interaction or specific targeting to the fungal cell wall and cell membrane. Secondly, stimuli-responsive nanomaterials are developed to realize smart release of drugs in the specific microenvironment of pathological tissues, such as the fungal biofilm microenvironment and inflammatory microenvironment. Thirdly, nanomaterials can be designed to cross different physiological barriers, effectively addressing challenges posed by skin, corneal, and blood-brain barriers. Additionally, some new nanomaterial-based strategies in treating fungal infections are discussed, including the development of fungal vaccines, modulation of macrophage activity, phage therapy, the application of high-throughput screening in drug discovery, and so on. Despite the challenges faced in applying nanotechnology to antifungal therapy, its significant potential and innovation open new possibilities for future clinical antifungal applications.

Rosacea, a chronic inflammatory dermatological condition, is characterized by facial erythema and pustules. Recent investigations have delved into the interplay between the gut microbiota and rosacea pathogenesis, unveiling promising avenues for therapeutic intervention. In this study, we screened and isolated strains Ligilactobacillus salivarius 23-006 and Lacticaseibacillus paracasei 23-008 from the feces of healthy volunteers and evaluated the intervention effects of probiotics on rosacea by constructing an LL37 induced rosacea-like mouse model. Our results showed that both L. salivarius 23-006 and L. paracasei 23-008 were probiotic strains with favourable properties. In specific, we observed that both L. salivarius 23-006 and L. paracasei 23-008 alleviated skin lesions, reduced skin inflammatory infiltrates, and decreased the expression of inflammatory factors in mice, with the combination of L. salivarius 23-006 and L. paracasei 23-008 having the most significant effect. Moreover, the combination of strains reduced the expression of cathelicidin LL37 and rosacea-associated factors by inhibiting the TLR2/MyD88/NF-κB pathway. The 16S rRNA analysis showed that the combination enhanced the intestinal barrier, restored intestinal microbiota homeostasis, and up-regulated the abundance of Lactobacillus while down-regulating the abundance of Coprococcus and Oscillospira . We also explored the effects of postbiotics of L. salivarius 23-006 and L. paracasei 23-008 on rosacea. While postbiotics could also ameliorate the rosacea-like phenotype in mice via the TLR2/MyD88/NF-κB pathway, the effects were not as pronounced as those observed with probiotic treatment. However, the postbiotics still enhanced the intestinal barrier, up-regulated the Lactobacillus abundance, and modulated the intestinal microbiota. In conclusion, our study revealed that L. salivarius 23-006 and L. paracasei 23-008 improved rosacea by regulating the TLR2/MyD88/NF-κB pathway and intestinal microbiota, providing a theoretical basis for the treatment of rosacea.

Herein, we successfully fabricated ultra-small metal nanoparticles into two stable Zr-based metal-organic frameworks via in situ redox reactions between triphenylamine and the corresponding metal ions to afford Pd NPs@1 and Pd NPs@2, which exhibit excellent activity and reusability for Suzuki coupling reactions as heterogeneous catalysts.

In pursuit of developing alternatives for the highly polluting Haber-Bosch process for ammonia synthesis, the electrocatalytic nitrogen reduction reaction (NRR) using transition metal nitrides such as zirconium mononitride (ZrN) has been identified as a potential pathway for ammonia synthesis. In particular, specific facets of ZrN have been theoretically described as potentially active and selective for NRR. Major obstacles that need to be addressed include the synthesis of tailored catalyst materials that can activate the inert dinitrogen bond while suppressing hydrogen evolution reaction (HER) and not degrading during electrocatalysis. To tackle these challenges, a comprehensive understanding of the influence of the catalyst's structure, composition, and morphology on the NRR activity is required. This motivates the use of metal-organic chemical vapor deposition (MOCVD) as the material synthesis route as it enables catalyst nanoengineering by tailoring the process parameters. Herein, we report the fabrication of oriented and facetted crystalline ZrN thin films employing a single source precursor (SSP) MOCVD approach on silicon and glassy carbon (GC) substrates. First principles density functional theory (DFT) simulations elucidated the preferred decomposition pathway of SSP, whereas ab initio molecular dynamics simulations show that ZrN at room temperature undergoes surface oxidation with ambient O 2 , yielding a Zr-O-N film, which is consistent with compositional analysis using Rutherford backscattering spectrometry (RBS) in combination with nuclear reaction analysis (NRA) and X-ray photoelectron spectroscopy (XPS) depth profiling. Proof-of-principle electrochemical experiments demonstrated the applicability of the developed ZrN films on GC for NRR and qualitatively hint towards a possible activity for the electrochemical NRR in the sulfuric acid electrolyte.

As the two typical basic binary solid solutions of the relaxor-PbTiO 3 family, Pb(Mg 1/3 Nb 2/3 )O 3 -PbTiO 3 (PMN-PT) has been widely investigated, whereas Pb(Ni 1/3 Nb 2/3 )O 3 -PbTiO 3 (PNN-PT) has not. Here, 1.5 mol% Sm-doped (1 - x )Pb(Ni 1/3 Nb 2/3 )O 3 - x PbTiO 3 , (1 - x )PNN- x PT:0.015Sm with x = 0.33-0.39, ceramics have been prepared and the chemical composition-induced evolution of crystal structure, domain, and electrical properties investigated systematically. With increasing PT content, evolution of the rhombohedral-tetragonal structure was observed. A rhombohedral-tetragonal morphotropic phase boundary occurred around x = 0.36-0.37, which showed a peak piezoelectric property with piezoelectric constant d 33 = 531 pC N -1 and planar electromechanical coupling factor k p = 0.37 at room temperature. At the same time, the x = 0.36 composition showed improved ferroelectric behavior with remanent polarization P r = 13.4 μC cm -2 and coercive field E c = 3.2 kV cm -1 . Interestingly, different from its PMN-PT counterpart, there is no temperature-driven phase transition between room temperature and the Curie temperature for (1 - x )PNN- x PT:0.015Sm. These parameters indicated that the PNN-PT system is worthy of more attention and is a promising platform for further development of high-performance piezo/ferroelectric materials.

In the leather manufacturing industry, the management of substantial quantities of solid waste containing chrome shavings remains a formidable challenge. Concurrently, there is a pressing need for the development of pH-universal and economically viable electrocatalysts for the hydrogen evolution reaction (HER). In response to these intertwined challenges, this study proposes an innovative approach wherein the amino groups present on the surface of chrome shavings are utilized to immobilize single ruthenium atoms during pyrolysis, thereby facilitating the synthesis of hydrogen evolution electrocatalysts. The optimized sample, denoted as CN/Cr 2 O 3 /Ru-1, demonstrates exceptional electrocatalytic performance, exhibiting an ultra-low overpotential of -28 mV in 1.0 M KOH at a current density of 10 mA cm -2 , and it also exhibits good performance in acidic and neutral electrolytes. Importantly, these overpotentials surpass those reported for many previous ruthenium-based catalysts. Density functional theory (DFT) calculations elucidate that both oxygen (O) and chromium (Cr) moieties within Cr 2 O 3 can engage in favorable interactions with the coordination patterns of the ruthenium (Ru) atoms, thereby elucidating the synergistic enhancement conferred by the chromium element in CN/Cr 2 O 3 /Ru, which ultimately facilitates and promotes the catalytic activity of the ruthenium atoms serving as the catalytic center. This facile synthesis route not only presents a green solution for addressing waste chromium pollutants but also offers a promising avenue for the development of high-performance, cost-efficient electrocatalysts.

Nanopore technology, re-fueled by two-dimensional (2D) materials such as graphene and MoS 2 , controls mass transport by allowing certain species while denying others at the nanoscale and has a wide application range in DNA sequencing, nano-power generation, and others. With their low transmembrane transport resistance and high permeability stemming from their ultrathin nature, crystalline 2D materials do not possess nanoscale holes naturally, thus requiring additional fabrication to create nanopores. Herein, we demonstrate that nanopores exist in amorphous monolayer carbon (AMC) grown at low temperatures. The size and density of nanopores can be tuned by the growth temperature, which was experimentally verified by atomic images and further corroborated by kinetic Monte Carlo simulation. Furthermore, AMC films with varied degrees of disorder (DOD) exhibit tunable transmembrane ionic conductance over two orders of magnitude when serving as nanopore membranes. This work demonstrates the DOD-tuned property in amorphous monolayer carbon and provides a new candidate for modern membrane science and technology., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Biology exploits biomacromolecular phase separation to form condensates, known as membraneless organelles. Despite significant advancements in deciphering sequence determinants for phase separation, modulating these features in vivo remains challenging. A promising approach inspired by biology is to use post-translational modifications (PTMs)-to modulate the amino acid physicochemistry instead of altering protein sequences-to control the formation and characteristics of condensates. However, despite the identification of more than 300 types of PTMs, the detailed understanding of how they influence the formation and material properties of protein condensates remains incomplete. In this study, we investigated how modification with myristoyl lipid alters the formation and characteristics of the resilin-like polypeptide (RLP) condensates, a prototypical disordered protein with upper critical solution temperature (UCST) phase behaviour. Using turbidimetry, dynamic light scattering, confocal and electron microscopy, we demonstrated that lipidation-in synergy with the sequence of the lipidation site-significantly influences RLPs' thermodynamic propensity for phase separation and their condensate properties. Molecular simulations suggested these effects result from an expanded hydrophobic region created by the interaction between the lipid and lipidation site rather than changes in peptide rigidity. These findings emphasize the role of "sequence context" in modifying the properties of PTMs, suggesting that variations in lipidation sequences could be strategically used to fine-tune the effect of these motifs. Our study advances understanding of lipidation's impact on UCST phase behaviour, relevant to proteins critical in biological processes and diseases, and opens avenues for designing lipidated resilins for biomedical applications like heat-mediated drug elution.

Polymeric heart valves (PHVs) present a promising alternative for treating valvular heart diseases with satisfactory hydrodynamics and durability against structural degeneration. However, the cascaded coagulation, inflammatory responses, and calcification in the dynamic blood environment pose significant challenges to the surface design of current PHVs. In this study, we employed a surface-initiated polymerization method to modify polystyrene- block -isobutylene- block -styrene (SIBS) by creating three hydrogel coatings: poly(2-methacryloyloxy ethyl phosphorylcholine) (pMPC), poly(2-acrylamido-2-methylpropanesulfonic acid) (pAMPS), and poly(2-hydroxyethyl methacrylate) (pHEMA). These hydrogel coatings dramatically promoted SIBS's hydrophilicity and blood compatibility at the initial state. Notably, the pMPC and pAMPS coatings maintained a considerable platelet resistance performance after 12 h of sonication and 10 000 cycles of stretching and bending. However, the sonication process induced visible damage to the pHEMA coating and attenuated the anti-coagulation property. Furthermore, the in vivo subcutaneous implantation studies demonstrated that the amphiphilic pMPC coating showed superior anti-inflammatory and anti-calcification properties. Considering the remarkable stability and optimal biocompatibility, the amphiphilic pMPC coating constructed by surface-initiated polymerization holds promising potential for modifying PHVs.

The Open Databases Integration for Materials Design (OPTIMADE) application programming interface (API) empowers users with holistic access to a growing federation of databases, enhancing the accessibility and discoverability of materials and chemical data. Since the first release of the OPTIMADE specification (v1.0), the API has undergone significant development, leading to the v1.2 release, and has underpinned multiple scientific studies. In this work, we highlight the latest features of the API format, accompanying software tools, and provide an update on the implementation of OPTIMADE in contributing materials databases. We end by providing several use cases that demonstrate the utility of the OPTIMADE API in materials research that continue to drive its ongoing development., Competing Interests: G. J. C. is a shareholder and Director of Intellegens Ltd. G.-M. R. is a shareholder and Chief Innovation Officer of Matgenix SRL. E. B. is a shareholder and Director of Materials Platform for Data Science OÜ., (This journal is © The Royal Society of Chemistry.)

Microgels have become a popular and powerful structural unit in the bioprinting field due to their advanced properties, ranging from the tiny size and well-connected hydrogel (nutrient) network to special rheological properties. Different microgels can be fabricated by a variety of fabrication methods including bulk crushing, auxiliary dripping, multiphase emulsion, and lithography technology. Traditionally, microgels can encapsulate specific cells and are used for in vitro disease models and in vivo organ regeneration. Furthermore, microgels can serve as a drug carrier to realize controlled release of drug molecules. Apart from being used as an independent application unit, recently, these microgels are widely applied as a specific bioink component in 3D bioprinting for in situ tissue repair or building special 3D structures. In this review, we introduce different methods used to generate microgels and the microgel-based bioink for bioprinting. Besides, the further tendency of microgel development in future is introduced and predicted to provide guidance for related researchers in exploring more effective ways to fabricate microgels and more potential bioprinting application cases as multifunctional bioink components.

Efficient and affordable nucleic acid detection methods play a pivotal role in various applications. Herein, we developed an immobilization-free and label-free strategy to construct a photoelectrochemical nucleic acid biosensing platform based on interactions between silver nanoparticles and DNA. First, CRISPR-Cas12a exhibited a trans-cleavage effect on adenine nucleotide sequences upon recognizing the target DNA. The resulting adenine nucleotide sequences of varying lengths then engaged in interactions with silver nanoparticles, leading to a solution characterized by distinct light transmittance. Subsequently, the solution was positioned between the light source and the photoelectrode, strategically impacting the photon absorption step within the photoelectrochemical process. Consequently, the detection of nucleic acid was accomplished through the analysis of the resultant photocurrent signal. The developed platform exhibits a detection limit of 0.06 nM (S/N = 3) with commendable selectivity. The innovative use of adenine nucleotide sequences as cost-effective probes interacting with silver nanoparticles eliminates the need for complex interfacial immobilization processes, significantly simplifying the fabrication of DNA sensors. The outcomes of our research present a promising pathway for advancing the development of economically feasible miniature DNA sensors.

The present investigation delves into the adverse environmental impact of atmospheric pollutant gases, specifically nitrogen dioxide (NO 2 ) and sulfur dioxide (SO 2 ), which necessitates the identification and implementation of effective control measures. The central objective of this study is to explore the eradication of these pollutants through the utilization of aluminum Al 13 and Al 15 metal clusters, distinguished by their unique properties. The comprehensive evaluation of gas/cluster interactions is undertaken employing density functional theory (DFT). Geometric optimization calculations for all structures are executed using the ωB97XD functional and the Def2-svp basis set. To probe various interaction modalities, gas molecule distribution around the metal clusters is sampled using the bee colony algorithm. Frequency calculations employing identical model chemistry validate the precision of the optimization calculations. The quantum theory of atoms in molecules (QTAIM) and natural bond orbital (NBO) methodologies are applied for the analysis of intermolecular interactions. This research establishes the robust formation of van der Waals attractions between the investigated gas molecules, affirming aluminum metal clusters as viable candidates for the removal and control of these gases., Competing Interests: There is no conflict of interest for this manuscript., (This journal is © The Royal Society of Chemistry.)

The discovery of new antibacterials within the vast chemical space is crucial in combating drug-resistant bacteria such as methicillin-resistant Staphylococcus aureus (MRSA). However, the traditional approach of screening the entire chemical library in an ergodic manner can be laborious and time-consuming. Machine learning-assisted screening of antibacterials alleviates the exploration effort but suffers from the lack of reliable and related datasets. To address these challenges, we devised a combinatorial library comprising over 110 000 candidates based on the Ugi reaction. A focused library was subsequently generated through uniform sampling of the entire library to narrow down the preliminary screening scale. A novel feature-fusion architecture called the latent space constraint neural network was developed which incorporated both fingerprint and physicochemical molecular descriptors to predict the antibacterial properties. This integration allowed the model to leverage the complementary information provided by these descriptors and improve the accuracy of predictions. Three lead compounds that demonstrated excellent efficacy against MRSA while alleviating drug resistance were identified. This workflow highlights the integration of machine learning with the combinatorial chemical library to expedite high-quality data collection and extensive data mining for antibacterial screening., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Flexible pressure sensors overcome the limitations of traditional rigid sensors on the surface of the measured object, demonstrating broad application prospects in fields such as sports health and vital sign monitoring due to their excellent flexibility and comfort in contact with the body. MXene, as a two-dimensional material, possesses excellent conductivity and abundant surface functional groups. Simultaneously, MXene's unique layered structure and large specific surface area offer a wealth of possibilities for preparing sensing elements in combination with other materials. This article reviews the preparation methods of MXene materials and their performance indicators as sensing elements, discusses the controllable preparation methods of MXene materials and the impact of their physical and chemical properties on their functions, elaborates on the pressure sensing mechanism and evaluation mechanism of MXene materials. Starting from the four specific application directions: aerogel/hydrogel, ink printing, thin film/electronic skin, and fiber fabric, we introduce the research progress of MXene flexible pressure sensors from an overall perspective. Finally, a summary and outlook for developing MXene flexible pressure sensors are provided., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Real-time monitoring of biocatalytic-based processes is significantly improved and simplified when they can be visualized. Visual monitoring can be achieved by integrating a fluorescent unit with the biocatalyst. Herein, we outline the design strategies of fluorescent probes for monitoring biocatalysis: (1) probes for monitoring biocatalytic transfer: γ-glutamine is linked to the fluorophore as both a recognition group and for intramolecular charge transfer (ICT) inhibition; the probe is initially in an off state and is activated via the transfer of the γ-glutamine group and the release of the free amino group, which results in restoration of the "Donor-π-Acceptor" (D-π-A) system and fluorescence recovery. (2) Probes for monitoring biocatalytic oxidation: a propylamine is connected to the fluorophore as a recognition group, which cages the hydroxyl group, leading to the inhibition of ICT; propylamine is oxidized and subsequently β-elimination occurs, resulting in exposure of the hydroxyl group and fluorescence recovery. (3) Probes for monitoring biocatalytic reduction: a nitro group attached to a fluorophore as a fluorescence quenching group, this is converted to an amino group by catalytic reduction, resulting in fluorescence recovery. (4) Probes for monitoring biocatalytic hydrolysis: β-D-galactopyranoside or phosphate acts as a recognition group attached to hydroxyl groups of the fluorophore; the subsequent biocatalytic hydrolysis reaction releases the hydroxyl group resulting in fluorescence recovery. Following these 4 mechanisms, fluorophores including cyanine, coumarin, rhodamine, and Nile-red, have been used to develop systems for monitoring biocatalytic reactions. We anticipate that these strategies will result in systems able to rapidly diagnose and facilitate the treatment of serious diseases.

Paper-based ratiometric fluorescence sensors are normally prepared using two or more types of fluorescent materials on a paper chip for simple, low-cost and fast detection. However, the choice of multi-step and one-step modifications on the paper chip affects the analytical performance. Herein, a novel paper-based dual-emission ratiometric fluorescence sensor was designed for the selective detection of tetracycline (TC). Carbon dots (CDs) modified with Eu 3+ were combined with a sealed paper-based microfluidic chip by two methods: one-step grafting of CDs-Eu 3+ on paper and step-by-step grafting of CDs and Eu 3+ on paper. The analytical performance was studied and optimized respectively. The red fluorescence of Eu 3+ at 450 nm is enhanced and the blue fluorescence of CDs at 617 nm is quenched by energy transfer in the presence of TC. Under optimal conditions, TC is selectively determined in the linear range from 0.1 μM to 100 μM with a detection limit of 0.03 μM by the step-by-step grafting method. In addition, the sealed paper chip could effectively prevent pollution and volatilization from the reagent. This technique has been used to analyze TC in seafood aquaculture water with satisfactory results.

Using activated-carbon-based electrodes derived from waste biomass in super-capacitor energy technologies is an essential future strategy to achieve sustainable energy and environmental protection. Biomass feed-stocks such as bamboo and straw have been used to prepare activated carbon-based electrodes. This experiment used peanut shells (waste biomass) as carbon precursors. Peanut shell-activated biochar materials were prepared using KOH activation and heat treatment, and SnO 2 @KBC-CNTs, a composite electrode material of biochar loaded with tin oxide. It was produced through hydrothermal synthesis, utilizing SnCl 4 -5H 2 O as the tin precursor. The application of KOH activators during pyrolysis markedly enhanced the porosity and specific surface area of the resultant activated biochar, due to effective dispersion and degradation of pyrolytic products. Characterized by a micro-mesoporous structure, the composite's pores boasted a specific surface area of 158.69 m 2 g -1 . When tested at a density of current of 0.5 A g -1 , the specific capacitance of SnO 2 @KBC-CNTs reached 198.62 F g -1 , nearly doubling the performance of the KBC electrode material alone. Moreover, the composite demonstrated a low ion transfer resistance of 0.71 Ω during charge-discharge cycles., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)

Resveratrol, renowned as an antioxidant, also exhibits significant potential in combatting severe respiratory infections, particularly the respiratory syncytial virus (RSV). Nevertheless, the specific mechanism underlying its inhibition of RSV replication remains unexplored. Heparan sulfate proteoglycans (HSPGs) play a pivotal role as attachment factors for numerous viruses, offering a promising avenue for countering viral infections. Our research has unveiled that resveratrol effectively curbs RSV infection in a dose-dependent manner. Remarkably, resveratrol disrupts the early stages of RSV infection by engaging with HSPGs, rather than interacting with RSV surface proteins like fusion (F) protein and glycoprotein (G). Resveratrol's affinity appears to be predominantly directed towards the negatively charged sites on HSPGs, thus impeding the binding of viral receptors. In an in vivo study involving RSV-infected mice, resveratrol demonstrates its potential by ameliorating pulmonary pathology. This improvement is attributed to the inhibition of pro-inflammatory cytokine expression and a reduction in viral load within the lungs. Notably, resveratrol specifically alleviates inflammation characterized by an abundance of neutrophils in RSV-infected mice. In summation, our data first shows how resveratrol combats RSV infection through interactions with HSPGs, positioning it as a promising candidate for innovative drug development targeting RSV infections. Our study provides insight into the mechanism of resveratrol antiviral infection.

Developing a fluidic platform that combines high-throughput with reconfigurability is essential for a wide range of cutting-edge applications, but achieving both capabilities simultaneously remains a significant challenge. Herein, we propose a novel and unique method for droplet manipulation via drawing surface charge graphics on electrode-free papers in a contactless way. We find that opposite charge graphics can be written and retained on the surface layer of porous insulating paper by a controlled charge depositing method. The retained charge graphics result in high-resolution patterning of electrostatic potential wells (EPWs) on the hydrophobic porous surface, allowing for digital and high-throughput droplet handling. Since the charge graphics can be written/projected dynamically and simultaneously in large areas, allowing for on-demand and real-time reconfiguration of EPWs, we are able to develop a charge-graphic fluidic platform with both high reconfigurability and high throughput. The advantages and application potential of the platform have been demonstrated in chemical detection and dynamically controllable fluidic networks.

The application of selenium-based non-covalent bond catalysis in living cationic polymerization has rarely been reported. In this work, the cationic polymerization of p -methoxystyrene ( p MOS) was performed using a bidentate selenium bond catalyst - a new water-tolerant Lewis acid catalyst. A polymer with controllable molecular weight and narrow molecular weight distribution can be obtained at room temperature, with a maximum molecular weight of 23.3 kDa. This selenium bond compound can also catalyze the controllable cationic polymerization of p -methoxy styrene under environmental conditions. By changing the monomer feeding ratio, a secondary feeding experiment and DFT analysis, it is shown that the selenium bond catalyst can induce polymer chain growth by reversibly activating dormant covalent bonds (C-OH).

Acute kidney injury (AKI) is a global health threat due to its high morbidity and mortality. There is still a lack of effective therapeutic methods to deal with AKI clinically. Natural products with outstanding accessibility and bioactivity are potential candidates for AKI treatment. Natural product-based prodrugs or nano-structures with improved properties are frequently fabricated for maximizing bioavailability and decreasing side effects, in which natural polymers are selected as carriers, or natural drugs are loaded as cargos on designed polymers. In this review, the etiologies of AKI are briefly presented, and emerging natural products delivered rationally for AKI therapy, as either carriers or cargos, are both introduced. Moreover, the challenges of the future development of nature-based nanodrugs or prodrugs for AKI have also been discussed.

The coupling of two-dimensional van der Waals heterojunctions is an effective way to achieve photocatalytic hydrogen production. This paper designs the Mo x W 1- x S 2 /AlN ( x = 0, 0.25, 0.5, 0.75, 1) van der Waals heterojunction as a possible photocatalytic material. By using first-principles calculations, the effects of different Mo/W ratios on the band gap and photocatalytic hydrogen production performance of heterojunctions were investigated. The results show that the heterojunction is a direct Z-scheme photocatalyst and can achieve overall water splitting. By calculating the absorption spectrum, it is found that the heterojunction has a wider visible light absorption range when the bimetal is added, and there is still a strong absorption peak at 615 nm. With the increase of the Mo atom ratio, the absorption spectrum is red-shifted. The Gibbs free energy of the two-component Mo 0.5 W 0.5 S 2 /AlN heterojunction is only -0.028 eV. Our work provides a new perspective for the modification of 2D transition metal dichalcogenide photocatalytic heterojunctions.

Colloidal calcium phosphate (CCP) confers a modifiable structure to micellar casein (MC), which endows it with potential advantages as a delivery carrier. However, it is difficult to achieve multipattern release of the core material in the intestine with MC as a single wall. In this study, we prepared an anthocyanin-casein-based delivery system utilizing MC with different freezing degrees as the wall material with the objective of achieving the controlled release of anthocyanin as the model core in the intestine. The results showed that freezing could significantly reduce the CCP level up to 50%. Static in vitro simulated digestion with the addition of exogenous Ca 2+ showed that the designed delivery system exhibited low anthocyanin release (15%-35%) in the gastric tract. The pattern of release in the intestine depended on the CCP dissociation degree. High and low dissociation degrees corresponded to slow release (from 15% to 65% within 2 h) and burst release (from 35% to 90% within 5 min), respectively. WAXS/SAXS analysis revealed that exogenous serum Ca 2+ inherent in simulated gastric fluid and endogenous serum Ca 2+ induced by CCP dissociation was synergistically involved in the reconstitution of CCP-mediated nanoclusters and large aggregates. The freezing degree of MC determined the endogenous serum Ca 2+ level, which influenced the gastric aggregation behavior of wall MC and ultimately led to a fairly different gastrointestinal release behavior of anthocyanins.

The eyes have a complicated microenvironment with many clearance mechanisms, making it challenging for effective drug delivery to the targeted areas of the eyes. Substrate transport mediated by active transporters is an important way to change drug metabolism in the ocular microenvironment. We designed multifunctional, dual-adaptive nanomicelles (GSCQ@NTB) which could overcome multiple physiological barriers by acting on both the efflux transporter and influx transporter to achieve deep delivery of the P-gp substrate in the cornea. Specifically, an effective "triple" antiangiogenic agent, nintedanib (NTB), was loaded into the biocompatible micelles. The expression of the efflux transporter was reversed by grafting quercetin. The peptide (glycylsarcosine, GS) was modified to target the influx transporter "Peptide Transporter-1" (PepT-1). Quercetin (QRT) and nintedanib (NTB) were transported to the cornea cooperatively, achieving long retention on the ocular surface and high compatibility. In a New Zealand rabbit model, within 8 hours after local administration, GSCQ@NTB was enriched in corneal stromal neovascularization and effectively inhibited the progress of neovascularization. Its effectiveness is slightly better than that in the first-line clinical application of steroids. In this study, we introduce the preparation of a dual adaptive nano-micelle system, which may provide an effective non-invasive treatment for corneal neovascularization.

Foreign body response (FBR) represents an immune-mediated cascade reaction capable of inducing the rejection of foreign implants, thereby compromising their in vivo performance. Pure zwitterionic hydrogels have demonstrated the ability to resist long-term FBR, owing to their outstanding antifouling capabilities. However, achieving such a robust anti-FBR effect necessitates stringent requirements concerning the purity of zwitterionic materials, which constrains their broader functional applications. Herein, we present a biocompatible, controllably degradable, and functionalizable zwitterion-albumin hybrid hydrogel. The zwitterionic hydrogel crosslinked with serum albumin exhibits controllable degradation and excels in preventing the adsorption of various proteins and adhesion of cells and bacteria. Moreover, the hydrogel significantly alleviates the host's FBR compared with PEG hydrogels and particularly outperforms PEG-based cross-linker crosslinked zwitterionic hydrogels in reducing collagen encapsulation when subcutaneously implanted into mice. The zwitterion-albumin hybrid hydrogel shows potential as a functionalizable anti-FBR material in the context of implantable materials and biomedical devices.

Excitotoxicity due to excessive activation of NMDARs is one of the main mechanisms of neuronal death during ischemic stroke. Previous studies have suggested that activation of either synaptic or extrasynaptic GluN2B-containing NMDARs results in neuronal damage, whereas activation of GluN2A-containing NMDARs promotes neuronal survival against ischemic insults. This study applied a systematic in silico , in vitro , and in vivo approach to the discovery of novel and potential GluN1/2A NMDAR positive allosteric modulators (PAMs). Ten compounds were obtained and identified as potential GluN1/2A PAMs by structure-based virtual screening and calcium imaging. The neuroprotective activity of the candidate compounds was demonstrated in vitro . Subsequently, compound 15 ( aegeline ) was tested further in the model of transient middle cerebral artery occlusion (tMCAO) in vivo , which significantly decreased cerebral infarction. The mechanism by which aegeline exerts its effect on allosteric modulation was revealed using molecular dynamics simulations. Finally, we found that the neuroprotective effect of aegeline was significantly correlated with the enhanced phosphorylation of cAMP response element-binding protein (CREB). Our study discovered the neuroprotective effect of aegeline as a novel PAM targeting GluN1/2A NMDAR, which provides a potential opportunity for the development of therapeutic agents for ischemic stroke., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)

Mechanical response luminescence (MRL) describes the photophysical properties triggered by mechanical stimulation. Usually, MRL can be regulated by intermolecular interactions, molecular conformation or molecular packing, to achieve the desirable optical properties. Herein, at the molecular level, this review covers the factors that influence mechanically responsive fluorescent materials, involving the single- or multifactorial modulation of aliphatic chains, donor-receptor switch, substituent adjustment, and position isomerism. According to these factors, the structure-activity strategies can be summarized as: (i) the self-recovery of optical properties, from the final to initial state, can be regulated by introducing long alkyl chains to a fluorophore. (ii) The sensitivity of MRL materials can be controlled by modifying the donor-acceptor structure via the changed ICT (intramolecular charge transfer) and intramolecular interaction. (iii) The electronic and steric effects of substituents can affect ICT and intermolecular interactions, thereby resulting in high quantum yield and high-contrast MRL materials via changing the molecular stacking of crystalline states. (iv) Intermolecular interaction is modulated by the position isomerism of the substituents, which results in switched molecular packing for the extended response toward a wide range of stimuli. It is anticipated that the molecular mechanisms of these structure-activity relationships will serve as a significant reference for developing novel, high contrast, recyclable mechanical response luminous materials.

The coupling of hetero monolayers into van der Waals (vdW) heterostructures has become an effective way to obtain tunable physical and chemical properties of two dimensional (2D) materials. In this work, based on first principles calculations, we systematically explore the electronic and magnetic properties of a 2D VOCl 2 /PtTe 2 heterostructure. Our results indicate that the ground state of the VOCl 2 /PtTe 2 heterostructure is a ferromagnetic (FM) metal with large magnetic anisotropy energy, among which, the VOCl 2 "sublayer" shows FM half metallic properties while the PtTe 2 "sublayer" shows nonmagnetic metallic properties. The Curie temperature ( T C ) of VOCl 2 /PtTe 2 is 111 K. Moreover, the FM-antiferromagnetic (AFM) phase transition can be obtained under biaxial strain. Our work provides an effective way to improve the performance of 2D monolayers in nano-electronic devices., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In this study, the photocatalytic properties of AlN/TMO heterojunctions formed by coupling MoO 2 and WO 2 of transition metal oxides with AlN are studied in detail using first-principles calculations with the aim of finding efficient and low-cost photocatalysts for water splitting to produce hydrogen to reduce environmental pollution. The AIMD, phonon spectrum, and elastic constants demonstrated the thermodynamic, kinetic, and mechanical stabilities of the AlN/TMO heterojunction. The results showed that the AlN/MoO 2 (1.55 eV) and AlN/WO 2 (1.99 eV) heterojunctions have typical type-II energy band arrangements, which can effectively promote the separation of photogenerated electrons and hole pairs. Meanwhile, the AlN/MoO 2 heterojunction showed excellent carrier mobilities (electron, 250.05 cm 2 V -1 S -1 and hole, 45 467.07 cm 2 V -1 S -1 ), which greatly exceeded those of each component. The AlN/WO 2 heterojunction showed an excellent HER (-0.07 eV) performance, which was close to the expected value. For the AlN/WO 2 heterojunction, a suitable band gap value, excellent HER, and other properties indicated that it has the potential to become a new candidate for photocatalytic water splitting. Our study enriches the theoretical research of transition metal oxide materials and wide-band gap materials by providing a reference direction for the design of reasonably high-quality photocatalysts.

The negative differential resistance (NDR) device is attracting attention because of its broad potential application in neuromorphic computing and non-volatile memory. However, only a limited range of materials show NDR and, therefore, there is less choice in material selection for NDR devices. Considering this issue, we here demonstrate a novel current controlled NDR device based on phase transformation. To the best of our knowledge, this report is the first experimental demonstration that NDR can be induced by phase transformation. We believe that the impact of this demonstration is very large, as phase transformation is the most common phenomenon in materials and consequently most materials can be reconsidered as possible candidates for NDR devices. The prototype NDR device is constructed using hydrogen absorbing metal palladium (Pd) thin-wire and the phase transformation from metal-hydride to metal is employed for the demonstration. The observed NDR property shows a strong dependence on the current sweep speed. Also, it exhibits no current polarity dependence. Therefore, the NDR device based on phase transformation is significantly different from typical NDR devices such as tunnel diodes and memristors. The prototype NDR device has been found to be very useful for evaluating the hydrogen storage properties of metals. The advantage of this analysis method is that the storage properties can be acquired just by sweeping the applied current. This demonstration offers novel directions for both the development and utilization of NDR devices.

Recently, mechanical biosensors have attracted more attention on single molecule detection due to its high accuracy, low cost, and convenience. However, the sensitivity of the mechanical biosensors restricted their clinical application. Herein, a mechanical biosensor based on membrane-mediated magneto-stress-electric coupled sensitization (MSEC-MMB) was developed to enhance performance. Through introducing Fe 3 O 4 nanoparticles (MNPs) to traditional stress-electric biosensors and applying a magnetic field, a magneto-stress-electric coupled biosensing system was constructed. The sensitivity of the MSEC-MMB was improved via enhancing the deformation of the mechanical membrane, which was demonstrated by detecting HSA. The optimal limit of detection (LOD) was 24 pg mL -1 under a magnetic field of 50 mT. The LOD was significantly 1 order of magnitude lower than that without the magnetic field. Besides, the MSEC-MMB showed a high specificity, selectivity, and stability. The clinical proteinuria samples were accurately detected, suggesting a good practicability of the MSEC-MMB. All these results proved the high sensitivity and practicality of the MSEC-MMB and provide a platform for early nephropathy diagnosis.

The majority of polymer-based materials demonstrate expansion upon absorbing water from the air. Mechanical metamaterials provide an interesting way to achieve unusual hygroscopic deformation. However, previous studies have only accommodated the limited tunability of negative hygroscopic expansion by theoretical analysis but have never involved other deformation modes. This work proposes modular reprogrammable 3D moisture-sensitive mechanical metamaterials with switchable hygroscopic deformation modes, which are built up of multi-material 3D-printed bi-material curved strips and cubic nodes. Depending on the geometrical parameters and spatial layouts of the curved strips, the metamaterials exhibit tunable coefficient of hygroscopic expansion from negative to positive. In addition to homogeneous deformation, complex 3D hygroscopic deformation modes can be achieved including shear and twist. More interestingly, the metamaterials are reprogrammable since all the deformation modes can be switched by modular disassembling and reassembling of the curved strips, just like LEGO building blocks. This work demonstrates a feasible approach to achieve customized 3D hygroscopic deformation through easy block building for specific engineering applications including eliminating hygroscopic stress, shape morphing structures, and smart actuators.

The inefficient treatment using protein-based nanovaccines is largely attributed to their inadequate immunogenicity. Herein, we developed a novel fluoropolymer (PF) via ring-opening polymerization and constructed a fluoropolymer-based nanovaccine for tumor immunotherapy. Due to the existence of fluoroalkyl chains, PF not only played a crucial role in tumor antigen delivery but also exhibited a remarkable adjuvant effect in enhancing the immunogenicity of nanovaccines. The nanovaccines formed by mixing PF with a model antigen ovalbumin (OVA) enhanced the uptake of antigen proteins by dendritic cells (DCs) and promoted the maturation and antigen presentation of DCs. Compared with free OVA, PF/OVA showed better efficacy in both pre-cancer prevention and tumor treatment. Furthermore, the proportion of CD4 + T and CD8 + T cells was significantly increased in lymph nodes and tumors of mice immunized with PF/OVA. Additionally, there was a great enhancement in the levels of key anti-tumor cytokines (TNF-α and IFN-γ) in the serum of the PF/OVA immunized mice. Our research has shown that fluoropolymer PF applied as a protein vector and adjuvant has great potential for the development of nanovaccines with robust immunogenicity.

Influenza A viruses typically cause acute respiratory infections in humans. However, virus-induced acute kidney injury (AKI) has dramatically increased mortality. The pathogenesis remains poorly understood due to limited disease models. Here, a distal renal tubular system-on-a-chip (dRTSC) was constructed to explore the pathogenesis. The renal tubule-vascular reabsorption interface was recapitulated by co-culturing the distal renal tubule and peritubular vessel with a collagen-coated porous membrane. To study the pathways of influenza virus entry into the kidney, dynamic tracking of fluorescence-labeled virus-infected blood vessels was performed. For the first time, the virus was shown to enter the kidney rapidly by cell-free transmission without disrupting the vascular barrier. Direct virus infection of renal tubules in dRTSC reveals disruption of tight junctions, microvilli formation, polar distribution of ion transporters, and sodium reabsorption function. This robust platform allows for a straightforward investigation of virus-induced AKI pathogenesis. The combination with single-virus tracking technology provides new insights into understanding influenza virus-induced extra-respiratory disease.

Charge-transfer (CT) cocrystals consisting of an electron donor and acceptor have gained attention for designing photothermal (PT) conversion materials with potential for biomedical and therapeutic use. However, the applicability of CT cocrystals is limited by their low stability and aqueous dispersity in biological settings. In this study, we present the self-assembly of CT cocrystals within hydrogen-bonded organic frameworks (HOFs), which not only allows for the dispersion and stabilization of cocrystals in aqueous solution but also promotes the CT interaction within the confined space of HOFs for photothermal conversion. We demonstrate that the CT interaction-driven self-assembly of tetrathiafulvalene (TTF) and tetracyanoquinodimethane (TCNQ) with PFC-1 HOFs results in the formation of cocrystal-encapsulated TQC@PFC-1 while retaining the crystalline structure of the cocrystal and PFC-1. TQC@PFC-1, in particular, exhibits significant absorption in the second near-infrared region (NIR-II) and excellent photothermal conversion efficiency, as high as 32%. Cellular delivery studies show that TQC@PFC-1 can be internalized in different types of cancer cells, leading to an effective NIR-II photothermal therapy effect both in cultured cells and in vivo . We anticipate that the strategy of self-assembly and stabilization of CT cocrystals in nanoscale HOFs opens the path for tuning their photophysical properties and interfacing cocrystals with biological settings for photothermal therapeutic applications.

Expression of concern for 'Bacterial infection microenvironment-responsive enzymatically degradable multilayer films for multifunctional antibacterial properties' by Qingqing Yao et al. , J. Mater. Chem. B , 2017, 5 , 8532-8541, https://doi.org/10.1039/C7TB02114C.

The field of biomaterials has experienced substantial evolution in recent years, driven by advancements in materials science and engineering. This has led to an expansion of the biomaterials definition to include biocompatibility, bioactivity, bioderived materials, and biological tissues. Consequently, the intended performance of biomaterials has shifted from a passive role wherein a biomaterial is merely accepted by the body to an active role wherein a biomaterial instructs its biological environment. In the future, the integration of bioinspired designs and dynamic behavior into fabrication technologies will revolutionize the field of biomaterials. This perspective presents the recent advances in the evolution of biomaterials in fabrication technologies and provides a brief insight into smart biomaterials.

Triple-negative breast cancer (TNBC) is one of the most aggressive cancers with an immunosuppressive microenvironment, and achieving a satisfactory effect from monotherapies, such as chemotherapy, photodynamic therapy (PDT) or immunotherapy, remains difficult. To solve this puzzle, a deepening synergistic therapy strategy of DNA damage and immunogenic cell death (ICD) stimuli was proposed. We engineered a doxorubicin (DOX) and 4-(hydroxymethyl) phenylboronic acid pinacol ester (PBAP) prodrug polymer, and encapsulated chlorin e6 (Ce6) to obtain the hyaluronidase (HAase) and H 2 O 2 dual-sensitive responsive nanoparticles (Ce6/HDP NPs). The NPs displayed efficient intratumoral accumulation and cellular internalization properties due to the active targeting of the hyaluronic acid (HA). The dual DNA damage of the chemotherapy and ROS production directly caused tumor cell apoptosis. The strong ICD stimuli, which were induced by ROS production and GSH depletion, generated an amplified immunogenicity to activate tumor immunotherapy in vivo . In this manner, the NPs could significantly inhibit primary tumor, abscopal tumor, pulmonary metastasis and recurrent tumor in a subcutaneous 4T1 tumor model, with effective biosafety. This study has provided a promising deepening synergistic therapy strategy against TNBC.

The fruit of Phyllanthus emblica Linn., which mainly grows in tropical and subtropical regions, is well-known for its medicine and food homology properties. It has a distinctive flavor, great nutritional content, and potent antioxidant, anti-inflammatory, anti-cancer and immunoregulatory effects. According to an increasing amount of scientific and clinical evidence, this fruit shows significant potential for application and development in the field of oral health management. Through the supplementation of vitamins, superoxide dismutase (SOD) and other nutrients reduce virulence expression of various oral pathogens, prevent tissue and mucosal damage caused by oxidative stress, etc . Phyllanthus emblica fruit can promote saliva secretion, regulate the balance of the oral microecology, prevent and treat oral cancer early, promote alveolar bone remodeling and aid mucosal wound healing. Thus, it plays a specific role in the prevention and treatment of common oral disorders, producing surprising results. For instance, enhancing the effectiveness of scaling and root planing in the treatment of periodontitis, relieving mucosal inflammation caused by radiotherapy for oral cancer, and regulating the blood glucose metabolism to alleviate oral discomfort. Herein, we systematically review the latest research on the use of Phyllanthus emblica fruit in the management of oral health and examine the challenges and future research directions based on its chemical composition and characteristics.

mRNA vaccines have emerged as a highly promising approach for preventing cancer and infectious diseases, attributed to their superior immunogenicity, rapid development speed, and quality-controlled scale production. While homologous mRNA vaccine administration is currently the most prevalent method employed in clinical settings, heterologous administration is a promising avenue worth exploring. In this report, two types of mRNA vaccine formulations for SARS-CoV-2 infection were developed based on different lipid nanoparticle (LNP) delivery systems, and heterologous and homologous mRNA vaccinations were administered to explore the levels of immune responses comparatively. First, five novel H-series ionizable lipids were synthesized and confirmed by NMR and MS. Subsequently, six SARS-CoV-2 receptor-binding domain (RBD) mRNA-encapsulated LNP formulations were prepared using a microfluidic mixer based on H-series and MC3 lipids. These formulations exhibited spherical structures with an average diameter ranging from 90-140 nm, as characterized by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The safety of these formulations was confirmed in vitro by the cytotoxicity assay. Moreover, transfection assay, lysosomal escape test, and western blot, and in vivo biodistribution analyses collectively demonstrated that lipids H03 and MC3 exhibited superior in vitro and in vivo delivery efficacy in comparison to other H-series lipids. Notably, H03-Fluc mRNA exhibited an approximately 2.2-fold higher in vivo bioluminescence signal intensity than MC3-Fluc mRNA. Additionally, evaluation of humoral immunity demonstrated that homologous H03-mRNA vaccination elicited an immune response that was approximately 3-fold higher than that of homologous MC3-mRNA vaccination. More significantly, the heterologous H03-mRNA/MC3-mRNA vaccination elicited an immune response that was approximately 2-3-fold higher than that of homologous H03-mRNA vaccination and 6-9-fold higher than that of homologous MC3-mRNA vaccination, without any observable adverse effects. These results suggest that heterologous mRNA vaccination is superior to homologous mRNA vaccination and may be attributed to differences in LNP carriers. Therefore, our research may inspire further exploration of different delivery systems to enhance mRNA-based therapeutics.

Heparin is a widely used anticoagulant agent in the clinic. After application, its anticoagulant effect must be reversed to prevent potential side effects. Protamine sulfate (PS) is the only clinically licensed antidote that has been used for this purpose in the last 80 years, which, however, provokes severe adverse effects, such as systemic hypotension and even death. Herein, we demonstrate the potential of supercharged polypeptides as a promising alternative for protamine sulfate. A series of supercharged polypeptides with multiple positive charges was recombinantly produced, and the heparin-neutralizing performance of the polypeptides was evaluated in comparison with PS. It was found that increasing the number of charges significantly enhanced the ability to neutralize heparin and resist the screening effect induced by salt. In particular, the polypeptide bearing 72 charges (K72) exhibited an excellent heparin-neutralizing behavior that was comparable to that of PS. Further in vivo studies revealed that the heparin-triggered bleeding was almost completely alleviated by K72 while a negligible toxic effect was observed. Therefore, such recombinant supercharged polypeptides might replace protamine sulfate as heparin-reversal agents.

The response of the magnetic field and strain engineering in an electrochemical process, such as the oxygen evolution reaction (OER), not only provides a strategy for enhancing catalytic performance through external fields and mechanical stress but also serves as a platform for revealing the functionality of multiple degrees of freedom in catalysts. The perovskite transition metal oxide (TMO) thin film with precise stoichiometry and lattice ordering enables atomic-level catalysis mechanisms in various electrochemical processes, thereby facilitating the design and engineering of promising catalysts. However, the perplexing dominance of spin in an OER process is still a puzzle due to the strong correlation between transition metal d and oxygen p orbitals. In this study, we utilized La 0.7 Sr 0.3 MnO 3 (LSMO) manganite as a ferromagnetic OER catalyst, which was directly deposited onto a flexible mica substrate. By subjecting LSMO to a tensile stress, we observed an enhanced OER, and the OER performance of LSMO improved by 30% with a +0.2% strain due to the weakened chemisorption of Mn-O. Moreover, it has been observed that the OER performance can be improved by approximately 87%, while the overpotential can be reduced by around 22% through the combination of a 5 kOe magnetic field and +0.2% strain. The OER performance of LSMO changed by ∼153% under 4% strain and 5 kOe magnetic field. Our experiments indicate that the primary source of the observed magnetic response is derived from the triplet state of O 2 , in which spin-polarized d and oxygen p orbitals decrease the spin potential within OER. This study provides experimental evidence for understanding the spin degree and electronic state regulation in the OER process, thereby facilitating further design and engineering of flexible magnetic electrochemistry catalysts with promising potential.

The use of microneedle (MN) systems has the potential to benefit a wide range of biomedical applications but is hindered by poorly controlled insertion. Herein, a novel MN penetration strategy is presented, which utilizes the recovery stress of near-infrared light-triggered shape memory polymers (SMPs) to drive MN insertion. This strategy enables force control over MN application with the precision of 15 mN through tunable light intensity. The pre-stretch strain of SMP can be further predetermined to provide a safety margin on penetration depth. Using this strategy, we demonstrate that MN can precisely insert into the stromal layer of the rabbit cornea. Additionally, the MN unit array allows programmable insertion for multistage and patterned payload delivery. This proof-of-concept strategy promises remotely, precisely, and spatiotemporally controlled MN insertion, which may inspire the further development of MN-related applications.