Metal Research Articles

Cobalt-assisted α-activation of ketones. Their arylation and keto-enol equilibrium confined into a macrocycle.

In this study, we explore the cobalt-mediated α-activation of ketones within modified porphyrin macrocycles, focusing on the arylation processes and the influence of macrocyclic confinement on keto-enol tautomerism. The activation of ketones such as acetone, butanone, 3-pentanone, and acetophenone and their possible transfer from a cobalt centre on the carbaporphyrin fragment results in the formation of new C(sp2)-C(sp3) bonds in confined macrocyclic environments of N-confused porphyrin and azuliporphyrin. Such modified ligands allow for following altered keto-enol equilibrium. They reversibly form unique structural motifs, azuleno[1,2-c]pyran and 2,4-dihydropyrano[3,4-c]pyrrole modulated by acid-base conditions and macrocyclic aromaticity. The coordination of a modified macrocycle to a rhodium(I) centre leads to a series of complexes with a final form with rhodium(III) in the cavity. The rhodium(III) centre cleaved the C(21)-C bond and transferred the acetone fragment back to the metal ion from the azulene fragment.

Influences of redox electrolyte containing AuNPs on microscopic surface structure, material removal and surface roughness of 20MnCr5 steel alloy during electrochemical machining

The chemical electrolytes are widely used in electrochemical machining (ECM) and have a significant effect on both the material removal rate (MRR) and the surface finish (Ra) of the workpiece. The process parameters of ECM, such as current density, electrolyte composition, and feed rate, are vital for optimizing machining performance. Research has indicated that high current density can create localized non-conductive passivating films, which impede metal dissolution. In this study, the aqueous solution of sodium nitrate (NaNO3) combined with gold nanoparticles (AuNPs) has been used as a novel electrolyte to evaluate the machining performance of the 20MnCr5 steel alloy. The inclusion of AuNPs in the NaNO3 solution enhanced local surface effects and promoted low-valence metal dissolution. The results demonstrated that the MRR and average surface roughness of the 20MnCr5 workpiece improved by 19.6% and 35.5%, respectively, when AuNPs were utilized compared to the alone NaNO3 electrolytic system. The experimental results also showed that the MRR increased within the current density range of 5.5 A/cm2 to 15.8 A/cm2, but declined in the range of 15.8 A/cm2 to 32.5 A/cm2. This decrease in the MRR at higher current densities can be attributed to the formation of non-conductive metal oxide passive layers. The oxygen evolution reaction (OER) was observed with the NaNO3 electrolyte at higher current densities, resulting in the formation of numerous micropores on the surface of the workpiece. In contrast, when the electrolyte was combined with AuNPs, these micropores ruptured quickly, creating new sites for the re-dissolution of metal ions. The microstructural changes on the machining surfaces under different operating conditions were analyzed using field emission scanning electron microscopy (FESEM), and the results are presented. Possible surface reactions, such as the formation of metal oxides and the release of oxygen gas, are discussed based on energy-dispersive X-ray (EDX) analysis and cyclic voltammetry (CV) studies.

Calprotectin elicits aberrant iron starvation responses in Pseudomonas aeruginosa under anaerobic conditions.

Pseudomonas aeruginosa is an opportunistic pathogen that uses several mechanisms to survive in the iron-limiting host environment. The innate immune protein calprotectin (CP) sequesters ferrous iron [Fe(II)], among other divalent transition metal ions, to limit its availability to pathogens. CP levels are increased in individuals with cystic fibrosis (CF), a hereditary disease that leads to chronic pulmonary infection by P. aeruginosa. We previously showed that aerobic CP treatment of P. aeruginosa induces a multi-metal starvation response that alters expression of several virulence properties. However, the CF lung is a hypoxic environment due to the growth of P. aeruginosa in dense biofilms. Here, we report that anaerobic CP treatment of P. aeruginosa induces many processes associated with an aerobic iron starvation response, including decreased phenazine production and increased expression of the PrrF small regulatory RNAs (sRNAs). However, the iron starvation response elicited by CP in anaerobic conditions shows characteristics that are distinct from responses observed in aerobic growth, including a lack of siderophore production and increased induction of genes for the FeoAB Fe(II) and Phu heme uptake systems. Also distinct from aerobic conditions, CP treatment induces expression of genes for predicted manganese transporters MntH1 and MntH2 during anaerobic growth while eliciting a less robust zinc starvation response compared to aerobic conditions. Induction of mntH2 is dependent on the PrrF sRNAs, suggesting a novel example of metal regulatory cross-talk. Thus, anaerobic CP treatment results in a multi-metal starvation response with key distinctions from aerobic conditions, revealing differences in P. aeruginosa metal homeostasis during anaerobic growth.IMPORTANCEIron is critical for most microbial pathogens, and the innate immune system sequesters this metal to limit microbial growth. Pathogens must overcome iron sequestration to survive during infection. For many pathogens, iron homeostasis has primarily been studied in aerobic conditions. Nevertheless, some host environments are hypoxic, including chronic lung infection sites in individuals with cystic fibrosis (CF). Here, we use the innate immune protein calprotectin, which sequesters divalent metal ions including Fe(II), to study the anaerobic iron starvation response of a common CF lung pathogen, Pseudomonas aeruginosa. We report several distinctions of this response during anaerobiosis, highlighting the importance of carefully considering the host environment when investigating the role of nutritional immunity in host-pathogen interactions.

Quercetin/Fe3O4@Cu(II) Hybrid Structures Fabrication and Cytotoxic Activity

In this study, firstly, the synthesis of magnetic Fe nanomaterials (Fe3O4 NMs) was carried out and then quercetin was immobilized into the synthesized nanomaterial. Synthesis of Organic@inorganic hybrid nanoflowers (Quercetin/Fe3O4@Cu (II) hNFs) was carried out using quercetin as the organic component and Cu (II) metal ions and Fe3O4 as inorganic components. Characterization of Quercetin/Fe3O4@Cu (II)hNFs was carried out using various methods such as FTIR, XRD, SEM, EDX, NTA and elemental mapping. Then, the anticancer activities of Quercetin/Fe3O4@Cu (II) hNFs were evaluated by the MTT method using the MCF7 (breast cancer) cell line.

Interaction of Small Nitriles Occurring in the Atmosphere of Titan with Metal Ions of Meteoric Origin.

Meteoric material injected into the atmosphere of Titan, Saturn's moon, can react with nitriles and other organic compounds that constitute Titan's atmosphere. However, specific chemical outcomes have not been fully explored. To understand the fates of meteoric metal ions in the Titan environment, reactions of Mg+ and Al+ with CH3CN (acetonitrile) and C2H5CN (propionitrile) were carried out using a drift cell ion reactor at room temperatures (300 K) and reduced temperatures (∼193 K) and modeled using density functional theory and coupled-cluster theory. Analysis of reactant ion electronic state distributions via electronic state chromatography revealed that Mg+ was produced in our instrument exclusively in its ground (2S) state, whereas Al+ was produced in both its 1S ground state and 3P first excited state. Mg+(2S) and Al+(1S) produce association products exclusively with both CH3CN and C2H5CN. Primary association reactions with C2H5CN occurred with higher reaction efficiencies than those with CH3CN. Mg+(2S) sequentially associates up to four nitrile ligands, and Al+(1S) associates up to three, each via the nitrile nitrogen. Computed binding energies are strongest for the first ligand and diminish with subsequent nitriles. Mg+(2S) exhibits a stronger preference for binding nitriles than Al+(1S) because its unpaired electron delocalizes to the nitrile ligands through back-bonding, whereas the lone pair on Al+(1S) remains localized on the metal center. Al+(3P) exhibited evidence of bimolecular product formation with both nitriles. Computational modeling of Al+(3P) with CH3CN suggests that the major product, AlCH3+, is kinetically favored over the more energetically stable product, Al+(HCN).

A Novel Mannich Based Metal II Complexes: Synthesis and Characterization of Magnetic, Conductivity and Antimicrobial Properties

A novel Mannich base (2R,9R)-2-((S)-((2-aminoethyl)amino)(2-hydroxyphenyl)methyl)-6-hydroxy-9-phenyl-2,3,4,9-tetrahydro-1H-xanthen-1-one (LI), composed from xanthene, salicylaldehyde, and ethylenediamine, was employed to synthesize unique complexes of Ni(II), Mn(II), Cr(II), Co(II), and Cu(II). The structural characteristics of the complexes were determined by studying microanalytical findings and using analytical methods such as EPR, FT-IR, 1H & 13C NMR, and UV-visible spectroscopy. The electronic spectra of the complexes suggested that the metal ion is fenced with octahedral structure. The molar conductivity of the metal chelates in DMSO was shown in the range of 18–28 Ω–1mol–1cm2. The EPR studies of the copper complex dissolved in dimethyl sulfoxide (DMSO) was obtained at temperature of 300 K, and its unique characteristics were analysed. The antimicrobial potential of the ligand and its complexes has been thoroughly examined towards K. pneumaniae, S. aureus, P. aeruginosa, E. coli, C. albicans, C. neoformans, M. audouinii, A. niger microorganisms. Experimental results have demonstrated that all of the complexes exhibit substantial antimicrobial action when related to both the unbound ligand and the standard. Furthermore, the validity of the biological research was verified through molecular docking antifungal and antibacterial tests. Overall, the obtained results confirm the multidirectional antimicrobial efficacy of the new Mannich base complexes and demonstrate their high pharmaceutical potential for further studies.

Co-doped perovskite nanocrystals for multiplexed anticounterfeiting applications.

Transition and lanthanide metal ion doping in colloidal perovskite nanocrystals results in efficient visible to near-infrared emission. Here, we explore the role of visible and near-infrared multi-emission pathways provided through Mn-doped and Yb-Mn co-doped perovskite nanocrystals within advanced photoluminescence-based security features. The features provide overt functionality through visible photoluminescence from the underlying Mn-dopants. Meanwhile, the Yb-dopants enable covert information to be concealed through their inherent near-infrared emission. These engineered printed patterns are assessed in terms of ambient, moisture, and thermal stability. Finally, the complexity of encryption is further enhanced by chemically engineering the host-dopant energy transfer processes through anion exchange reactions. This enables write and erase functions to be realised in these perovskite NC-based security features.

Ultra-Compact MXene/Alginate/PVA Composite Fibers by Intercalation and Chelation for Enhanced Flame Retardancy and Energy Harvesting.

MXene fibers with electro-conductivity and electrochemical properties have drawn growing research interest for its promising applications in wearable electronics, flexible electrodes, and smart textiles. However, producing MXene fibers with high strength keeps challenging because loose MXene sheets are hard to compact tightly due to electrostatic repulsion. Herein, ultra-compact MXene-based fibers are produced by intercalating alginate and polyvinyl alcohol (PVA) layers into MXene nanosheets and chelating via metal ions (i.e., Ca2+). The hydrogen and ionic bond are beneficial to compact MXene nanosheets and decrease the interplanar spacing, which improves the tensile strength. These result in MXene-based fibers with low porosity (0.2 vol%) and a high orientation factor of 0.877 exhibiting high electrical conductivity (1006 S cm‒1). In addition, flame retardancy is enhanced without smoldering owing to the synergistic effect of MXene and metal ions. Moreover, these compact MXene-based fibers with electromagnetic interference shielding, mechanical stability, acid, and alkali-resistant properties, and photo-thermal effect can be achieved for scale production. This strategy paves the way for the continuous production of compact functional fibers, applicable in flame retardant fabric, wireless communication, energy harvesting, and wearable flexible textiles.

Metal ion-modulated synthesis of γ-MnO2 nanosheet for catalytic oxidative degradation of clomiprazole.

Two-dimensional non-layered oxide nanosheets exhibit exceptional catalytic properties, offering significant potential for environmental applications. In this study, we report the development of a novel Fe-doped γ-MnO2 material with a hierarchical microsphere morphology, achieved through a metal ion regulation strategy. Unlike conventional sea urchin-like γ-MnO2, Fe doping induced a transformation to a two-dimensional non-layered structure composed of nanosheets, significantly increasing the specific surface area and exposing more active sites. The Fe-doped γ-MnO2 catalysts were evaluated for the degradation of chlorimiprazole (CBZ), a persistent pollutant, using a sulfate radical-based advanced oxidation process. Among the synthesized catalysts, NF-0.25Fe exhibited superior performance, achieving 93% CBZ removal within 16 min under near-neutral conditions. This exceptional activity was attributed to the optimized morphology, higher low-valence Mn content, and enhanced surface-active oxygen species. Systematic investigations revealed that the catalyst dosage, PMS concentration, and pH critically influenced the catalytic efficiency. This work demonstrates the potential of metal ion modulation in tailoring the structural and catalytic properties of transition metal oxides. The insights gained here provide a robust foundation for designing advanced nanomaterials for environmental remediation and other catalytic applications.

Using SERS to Evaluate Additive Kinetics During Reverse Pulse Plating of Cu

Abstract Metals, particularly precious and transition metals, have traditionally been utilized in the fabrication of electrochemical sensors. Despite significant progress, challenges remain, such as the risk of metal ions leaching out and the potential for the catalyst to separate from its support. Acid oxidation is a well-known process for treating and enhancing carbon materials for use in a wide range of applications. However, its potential to directly improve the performance of electrochemical sensors has not been fully explored. The present work highlights the fabrication of a metal-free electrochemical sensor based on carbon material derived from acid oxidation of waste coconut husk, which introduced more oxygen-containing functional groups. The acid-treated coconut husk was further modified by high-temperature pyrolysis to introduce nitrogen and sulfur heteroatoms. The electrochemical behavior of the fabricated sensor was assessed using cyclic voltammetry and linear sweep voltammetry for the detection of dopamine. The sensor displayed a LOD of 0.6 μM and a wide linear range (0.24 - 3.38 M). In addition, the selectivity, stability, and reproducibility (3.09 %) of the sensor were satisfactory. These findings suggest the promising potential of carbon materials as an effective platform for the development of ultra-sensitive point-of-care devices for monitoring human healthcare.

Stable Semitransparent All-Polymer Solar Cells with Color-Tunable Reflection and Neutral Transmission.

Enhancing the stability and optical tailorability of semitransparent organic solar cells (ST-OSCs) is crucial for building-integrated photovoltaics. In this work, we propose a smart design for realizing stable and color-tunable all-polymer ST-OSCs through integrating a self-assembled MeO-2PACZ layer capped in conjunction with an optically engineered coupling structure (dielectric layer/metal/dielectric layer). Owing to the effective blocking of interfacial diffusion of metal ions, the devices with MeO-2PACZ receive considerable gains of stability, as manifested by the retention of 90% of the initial efficiency after 4000 h under storage and a retention of 82% after 600 h at maximum power point tracking. The optical coupling layer enables independent modulation of reflective properties while maintaining a high transmittance neutrality. This results in colorful ST-OSCs with a wide reflective chrominance range and a peak light utilization efficiency of 3.62%, among the best for all-polymer ST-OSCs. This strategy advances next-generation, sustainable photovoltaic windows.

A novel disposable dual-sensing platform based on DNA-aptamer amplified with gold nanoparticles/Nb4C3-MXene for simultaneous detection of lead and cadmium

Herein, we designed a special screen-printing carbon electrode system with two independent zones to realize the immobilization of two kinds of aptamers on electrode surface. Nb4C3-MXene is a remarkable member from MX3 MXene with many excellent properties. In this study, Nb4C3-MXene nanosheets were firstly modified onto the screen-printing carbon electrode surface as the substrate materials to offer big surface area and then gold nanoparticles were loaded onto the surface of Nb4C3-MXene nanosheets through electrodeposition. Afterward, the aptamer-containing double-stranded DNA was spontaneously assembled onto the modified electrode surface through the Au–S bond. Owing to high affinity of aptamers towards the heavy metal ions (Cd2+ and Pb2+ in this case), the aptamers tagged with methylene blue and ferrocene would specifically bond with heavy metal ions to form folded structures and competed off from the electrode surface, and then the change of electrochemical signals can be detected by square wave voltammetry. The aptasensor exhibits a good linear response towards Cd2+ and Pb2+ from 1 × 10−10 to 1 × 10−7 M, and their detection limits are 59.8 pM of Pb2+ and Cd2+ of 146.2 pM; LOQ are 93.7 pM of Pb2+ and 164.8 pM of Cd2+, respectively.

Unraveling the Surface Chemistry of Aluminum Oxo Archimedean Cages for Efficient Serial Adsorption.

Multifunctional materials that meet diverse application needs hold profound significance in resource optimization, efficiency enhancement, and environmental sustainability. However, the development of these materials faces numerous challenges, including raw material acquisition, design feasibility, and long-term stability. This study demonstrates the innovative application of the surface chemistry of aluminum oxo Archimedean cages in efficient serial adsorption. The "Four-in-One" surface chemistry enables various single-crystal-to-single-crystal (SC-SC) structural transformations, involving ligand modification, cation exchange, post-synthetic metalation, and metal elimination, successfully achieving the first reversible SC-SC transformation from cluster structures to infinite frameworks. The fundamental reason behind these dynamic structural changes lies in the exceptional balance between rigidity and flexibility provided by the intercluster tri-pyrazole sites on the Archimedean cages. This diverse structural transformation characteristic offers extensive application potential for solid-liquid and solid-gas serial adsorption. For instance, this material effectively adsorbs heavy metal ions in water treatment and can subsequently be used for the permanent fixation of gaseous radionuclides. This work not only deepens our understanding of dynamic chemistry but also provides practical solutions for environmental remediation.

A cerium phthalocyanine-based covalent organic framework-magnetic core-shell composite as efficient affinity material for the enrichment of phosphopeptides.

Anovel cerium phthalocyanine-based covalent organic framework (CePc-COF)-magnetic core-shell composite was fabricated by grafting the CePc-COF layer on the surface of Fe3O4. The obtained core-shell composite particle (Fe3O4@CePc-COF) had strong magnetic responsiveness (29.6 emu g-1) and good hydrophilicity (5.0°). The affinity material provided abundant metal ion sites for specific enrichment of phosphopeptides. Fe3O4@CePc-COF had good performance in terms of high selectivity (1: 1: 5000), sensitivity (0.1 fmol), recovery (92.91%), and reusability (10 cycles). The enrichment feasibility of Fe3O4@CePc-COF was first investigated in standard peptides. Furthermore, Fe3O4@CePc-COF can efficiently identify phosphopeptides from extremely complex samples. The work can provide a novel idea for the fabrication of metallophthalocyanine based-COF materials for phosproteome detection in biological samples.

ZC3H13 Regulates Ferroptosis to Enhance Osteogenic Differentiation in Osteoporotic BMSCs.

Objectives: N6-methyladenosine (m6A) modification is critical in the regulation of osteoporosis (OP). Although ZC3H13 is an important m6A methyltransferase, its specific regulatory effects and mechanisms in osteoporosis are not yet fully understood. Therefore, we investigated the impact of ZC3H13 on the osteogenic potential of bone marrow-derived mesenchymal stem cells (BMSCs) in osteoporosis and attempted to elucidate its underlying mechanism. Materials and Methods: Western blotting, quantitative reverse transcription polymerase chain reaction, and immunohistochemical staining were used to identify changes in ZC3H13 and osteogenic factor (RUNX2 and OPN) expression in osteoporosis. Gain- and loss-of-function experiments were conducted to study the impact of ZC3H13 on the osteogenic differentiation of osteoporotic BMSCs (OP-BMSCs). Transcriptomic sequencing, transmission electron microscopy, and intraperitoneal injection of the ferroptosis inhibitor ferrostatin-1 (Fer-1) were used to elucidate the downstream mechanisms regulated by ZC3H13 in osteoporosis. In addition, rescue assays were performed to elucidate the underlying molecular mechanisms involved. Results: Here, we revealed that ZC3H13 was downregulated in OP-BMSCs and osteoporotic rat femurs, which correlated with the reduced osteogenic differentiation of OP-BMSCs. Functionally, ZC3H13 knockdown resulted in decreased osteogenic differentiation of the BMSCs, whereas ZC3H13 overexpression promoted the osteogenic differentiation of the OP-BMSCs. Furthermore, ZC3H13 knockdown was closely related to metal ion binding, reduced cell proliferation, and altered mitochondrial morphology. Treatment with the ferroptosis inhibitor Fer-1 partially reversed osteoporotic phenotypes invivo. Mechanistically, ZC3H13 was shown to promote osteogenic differentiation in OP-BMSCs by inhibiting ferroptosis. Conclusions: Our study revealed that ZC3H13 promoted the osteogenic differentiation of BMSCs by inhibiting ferroptosis in osteoporosis. This research offers a reliable theoretical foundation for predicting and treating osteoporosis.

Higher-Order CuI-Based Cages via Subcomponent Self-Assembly.

ConspectusCoordination cages formed via subcomponent self-assembly have found applications in fields including separation, sensing, catalysis, and the stabilization of reactive species, due to their guest binding abilities. Subcomponent self-assembly, which combines dynamic covalent bond (C═N) formation and reversible metal coordination (N→Metal), has enabled the preparation of many intricate polyhedral structures with minimal synthetic effort. This method has been used to prepare multitopic pyridyl-imine ligands that form the edges or faces of polyhedra, with octahedral metal ions, including FeII, CoII, and ZnII, defining the vertices. The use of CuI in subcomponent self-assembly is less widely reported, as the tetrahedral coordination geometry of CuI requires only two bidentate ligands, which can lead to lower-nuclearity assemblies instead of three-dimensional cages. The coordination flexibility of CuI also adds a challenge to the fabrication of well-defined nanostructures. This Account summarizes a series of higher-order CuI-based coordination cages and the design principles derived from their syntheses. Starting with the development of CuI assemblies and the challenges of preparing CuI cages, we discuss the circumvention of oligomer formation and control of the self-assembly process with CuI through (i) ligand engineering, (ii) vertex design, and (iii) guest-induced structural transformations. Aromatic stacking between corranulene-containing ligands is exploited to produce a 5-fold interlocked [2]catenane, whereas the incorporation of a sterically hindered triptycene subcomponent that minimizes aromatic stacking produces a double-octahedron and a hexagonal prism. These structures illustrate the importance of ligand engineering for obtaining complex CuI structures. We also explored the formation of cages with homo- or heterobimetallic vertices via two distinct strategies. First, dicopper(I) helicates were employed as cage vertices, and second, subcomponents with nonconverging coordination vectors were used. Such bimetallic vertices are challenging to incorporate when octahedral metal templates are used, but the flexibility of CuI renders them accessible. The closed-shell electronic configuration of CuI can endow the cages with photoluminescence, providing circularly polarized luminescence in the presence of helicity-enriched dicopper(I) vertices. The flexible coordination sphere of CuI also facilitates structural transformations upon the addition of suitable guests. One such system is able to self-sort to express the most thermodynamically stable host-guest complex and also undergo structural changes in response to different temperatures and solvents. The insights gained about the structural bases of these CuI cages may help enable the design of other novel CuI nanostructures with functions that may usefully differ from cages that exclusively incorporate octahedral metal centers.

Naphthazarin Mounted on the Manganese Carbonate Nanocube Induced Enrichment of Endogenous Copper and Fenton-like Reaction for Enhanced Chemodynamic Therapy.

Chemodynamic therapy (CDT), which utilizes transition metal ions to catalyze Fenton-like reactions for the eradication of tumor cells, has attracted substantial attention in the field of nanocatalysis. However, the therapeutic efficacy of CDT as a monotherapy is often limited by an insufficient level of hydrogen peroxide (H2O2) and the overexpressed glutathione (GSH) within tumor cells. Because of the high copper content in tumor tissues, a copper ionophore was strategically employed to enhance the intracellular accumulation of copper, thereby potentiating the CDT effect. Additionally, bovine serum albumin (BSA) was used to modify the copper ionophore, naphthazarin (Nap), to promote its targeting efficacy for tumor cells and to ensure its biosafety. The BSA-coated Nap nanoparticles, which could recruit Cu2+ in situ, were further deposited onto the surface of a manganese carbonate nanocube (Nap-BM NPs). The synergistic action of copper and manganese ions accelerated the decomposition of H2O2 into hydroxyl radicals (•OH) and consumed intracellular GSH, leading to cellular mortality via mitochondrial pathways. With low cytotoxicity and good biocompatibility in normal cells, the developed Nap-BM NPs significantly enhanced therapeutic outcomes by leveraging multiple Fenton-like reaction mechanisms to augment CDT, offering promising potential for clinical applications and contributing valuable insights into the field.

Peptide hydrogel platform encapsulating manganese ions and high-density lipoprotein nanoparticle-mimicking nanovaccines for the prevention and treatment of gastric cancer

BackgroundAdvanced gastric cancer remains a significant global health challenge, with limited therapeutic options available. In contrast, immunotherapy have emerged as promising alternatives, offering greater potency in treating advanced gastric cancer. However, the development of novel and efficient immunotherapeutic strategy is crucial to enhance the body’s immune response against gastric cancer.MethodsThis study developed a single-injection peptide hydrogel-based nanovaccine therapy for gastric cancer treatment. The therapy utilizes a RADA32 peptide hydrogel, which is sensitive to metal ion concentration, to encapsulate manganese ions and HPPS nanovaccines. The HPPS nanovaccines contain antigen peptide and CpG-ODN, designed to activate both the toll-like receptor 9 (TLR9) and cGAS-STING signaling pathways in antigen-presenting cells. This design aims to facilitate a stable and sustained release of the nanovaccine, thereby enhancing the body’s effective recognition and response to antigens.ResultsThe efficacy of the system was confirmed using the model antigen OVA and the gastric cancer-specific antigen MG7-related peptide. The results demonstrated that the nanovaccine effectively activated the immune response, leading to enhanced recognition and response to the antigens. This activation of both TLR9 and cGAS-STING pathways in antigen-presenting cells was crucial for the observed immune response, highlighting the potential of this approach to stimulate a robust and sustained immune response against gastric cancer.ConclusionsThis study presents a novel strategy for clinical anti-tumor vaccine administration, offering a promising approach for the prevention and treatment of gastric cancer. The single-injection peptide hydrogel-based nanovaccine system provides a convenient and effective method to enhance the body’s immune response against gastric cancer. This approach could potentially be expanded to other types of cancer, providing a versatile platform for cancer immunotherapy.

Unraveling the Surface Chemistry of Aluminum Oxo Archimedean Cages for Efficient Serial Adsorption

Multifunctional materials that meet diverse application needs hold profound significance in resource optimization, efficiency enhancement, and environmental sustainability. However, the development of these materials faces numerous challenges, including raw material acquisition, design feasibility, and long‐term stability. This study demonstrates the innovative application of the surface chemistry of aluminum oxo Archimedean cages in efficient serial adsorption. The "Four‐in‐One" surface chemistry enables various single‐crystal‐to‐single‐crystal (SC‐SC) structural transformations, involving ligand modification, cation exchange, post‐synthetic metalation, and metal elimination, successfully achieving the first reversible SC‐SC transformation from cluster structures to infinite frameworks. The fundamental reason behind these dynamic structural changes lies in the exceptional balance between rigidity and flexibility provided by the intercluster tri‐pyrazole sites on the Archimedean cages. This diverse structural transformation characteristic offers extensive application potential for solid‐liquid and solid‐gas serial adsorption. For instance, this material effectively adsorbs heavy metal ions in water treatment and can subsequently be used for the permanent fixation of gaseous radionuclides. This work not only deepens our understanding of dynamic chemistry but also provides practical solutions for environmental remediation.

Open-chain Tetrapyrroles Meet Metal Ions in the Functional Molecular Material Science.

Open-chain tetrapyrroles and their analogues, consisting of four pyrrole rings linked by methylene or methine carbons, originate from natural and synthetic pathways. These compounds exhibit unique structural flexibility due to their extended p-conjugation and tunable coordination with metal ions, enabling precise control over electronic and geometric properties. Such structural versatility makes them promising candidates for chiroptical, optoelectronic, and bio-related applications. By modulating metal coordination and molecular design, their functionalities can be tailored for circularly polarized luminescence, ion sensing, photothermal conversion, and chiral devices. This review highlights recent advancements in open-chain tetrapyrrole-based materials, emphasizing their structure-property relationships and potential for next-generation functional materials.