ACS Publications最新文献

Self-assembled proteins can significantly inhibit ice recrystallization, offering potential for cryoprotection. Here, soybean protein amyloid fibrils (SAFs) were fabricated via combined germination and acid-heat-induced fibrillation. Germination enhanced the fibrillation efficiency of soybean protein isolate (SPI). SAFs with the strongest ice recrystallization inhibition (IRI) activity were prepared from SPI of two-day germinated soybeans after 20 h of acidic-heat treatment (SAF-20). SAF-20 exhibited concentration-dependent IRI activity, with stronger inhibition of ice crystal growth at higher concentrations. It showed high ice-affinity adsorption and ice nucleation activity without altering ice crystal morphology. Structural analyses revealed that self-assembly promoted protein aggregation and increased surface hydrophobicity and β-sheet content. These changes strengthened hydrogen bonding at the ice-water interface, forming ordered interfacial water layers that disrupted long-range water ordering and inhibited ice crystal growth. Furthermore, SAF-20 significantly improved post-thaw recovery of cryopreserved Caco-2 cells, demonstrating its cryoprotective efficacy.

The microscopic state of polysaccharides in solution─whether dissolved, dispersed, or aggregated─directly dictates the macroscopic properties of the bulk fluid. However, the influence of their true state in solution and nanostructures on rheology is often overlooked. Here, using non-Newtonian shear-thickening fluids (STFs, SiO₂/poly(ethylene oxide)) as a model, we systematically investigate how xylan conformation and dispersion affect STFs' rheology. Xylan nanocrystals (XNCs) and water-soluble xylan ethers with distinct dispersibility (well-dispersed vs aggregate) and solubility (room-temperature-soluble vs high-temperature-soluble) are synthesized. Among those, well-dispersed XNCs and room-temperature-soluble xylan ethers exhibit a pronounced thickening effect in STFs, reducing the critical shear rate by 2 orders of magnitude and increasing peak viscosity by 880%. This work demonstrates that polysaccharide conformation and dispersion behavior exert pronounced effects on STF rheology, providing a new avenue for leveraging polysaccharides as fluid additives.

Small interfering RNAs (siRNAs) offer considerable promise as anticancer therapeutics because they enable the precise silencing of disease-related gene expression. However, its clinical potential is limited by rapid degradation and possible off-target toxicity, necessitating the development of an effective targeted delivery system. Bioengineered silk, a biocompatible and biodegradable material, can be tailored with functional peptides to enable nucleic acid binding and receptor-specific targeting. We developed five MS1 silk-based proteins that target VEGFR-1 or VEGFR-2, which are receptors that are frequently overexpressed in the tumor microenvironment (TME), including both endothelial and cancer cells. These were blended with MS2KN silk, which binds nucleic acids, to generate hybrid nanospheres. The resulting carriers exhibited high siRNA loading efficiency, selective binding to VEGFR-overexpressing endothelial and nonsmall cell lung cancer (NSCLC) cells, and efficient cellular uptake. Delivery of siRNA via these nanospheres led to a significant reduction in target gene expression. Our platform has strong potential for targeted siRNA delivery to VEGFR-overexpressing cells within the TME.

Supercapacitors, particularly porous carbon-based electric double-layer capacitors (PC-EDLCs), are crucial for next-generation energy storage but face limitations in capacitance enhancement and microstructure manipulation. Conventional carbonization-activation methods suffer from energy inefficiency, poor pore structure regulation, loss of functional groups, and inability to create optimal conducting-adsorption hybrid structures. This study presents a novel, tunable one-step thermal synthesis strategy based on the self-activation reaction of potassium carboxylate precursors. A precarbonization step is induced to enrich the oxygen-containing functional groups at the porous carbon surface, followed by activation at 800 °C. While this pretreatment reduces the specific surface area, it significantly increases the specific capacitance to 279 F g^-1 by introducing substantial pseudocapacitance and optimizing the conductivity of the carbon skeleton. The resulting carbonylated porous carbon exhibits outstanding supercapacitor performance, with a high capacitance retention of 93% after 10,000 cycles and an energy density of 12.8 Wh kg^-1. This work offers an efficient, energy-saving, and structurally tunable pathway for preparing high-performance porous carbon materials.

Inspired by mussel adhesion mechanisms and the structural advantages of double network (DN) hydrogels, this study developed a catechol- and polyphosphate-modified natural biomacromolecular-based DN hydrogel to tackle critical wound healing challenges, including persistent inflammation, oxidative stress, and impaired angiogenesis. The hydrogel exhibits tailored mechanical adaptability to wound microenvironments, ensuring conformal coverage under high-glucose conditions. Its inherent hemostatic capacity stems from rapid interfacial adhesion and coagulation activation, addressing the bleeding complications commonly observed in wounds. Furthermore, the hydrogel actively modulates pathological microenvironments via ROS scavenging and anti-inflammatory effects while facilitating sustained release of bioactive components to synergistically promote angiogenesis, collagen deposition, and epithelial regeneration. In summary, this mussel-inspired glycosyl cyclic hydrogel integrated multifunctional therapeutic advantages including microenvironment regulation, dynamic adaptability, and pro-regenerative signaling into a single platform, demonstrating great potential as a next-generation dressing for refractory diabetic wound management.

The need for multifunctional polymers in cellular environments arises from their potential applications in cancer treatment, drug delivery, gene delivery, imaging, sensing of different biomolecules, environmental and cellular engineering, etc. However, due to certain limitations, the direct polymerization of multifunctional polymers within cells is not feasible, as it faces many challenges. Therefore, this study emphasizes the synthesis of functionalized molecules outside the cells and subsequent modification of the polymers inside the cells through intracellular postpolymerization modification (iPPM). We investigate Förster resonance energy transfer (FRET) as a technique for confirming the occurrence of postpolymerization reactions in cells in real time without the need for extraction or purification. The FRET reaction consists of 7-nitrobenz-2-oxa-1,3-diazole (NBD) as the FRET donor, integrated as a segment in the polymer backbone, and rhodamine B-polyethylene glycol-dibenzocyclooctyne (RhB-PEG-DBCO) as the FRET acceptor. A copper-free click chemistry method is used as a postpolymerization reaction within cells by the reaction between the azide group on the polymer backbone and DBCO in the FRET acceptor. By employing FRET and a targeted approach, this technique contributes to the development of multifunctional polymers for diverse applications in cellular environments.

Developing adsorbents that couple high uranium affinity with durability in complex environments remains a pivotal challenge for efficient uranium harvesting. Here, we report a hierarchically engineered magnetic composite, Fe₃O₄@PAO@MPN-Met, that integrates (i) a superparamagnetic Fe₃O₄ core for rapid separation, (ii) an amidoxime-rich polyamidoxime (PAO) shell for uranyl chelation, (iii) a bioinspired metal-polyphenol network (MPN) adhesive layer, and (iv) an in situ mineralized Cu²⁺/d-methionine (d-Met) metal-organic framework (MOF) that imparts long-lasting antibiofouling activity. Stepwise solvothermal synthesis, surface grafting, and self-assembly preserve nanoscale morphology while reducing the saturation magnetization only to 16.4 emu/g─still sufficient for 1 min magnetic separation. Under optimal conditions, the material achieves a maximum uranium uptake of 272 mg/g, fitting the Langmuir model and quasi-second-order kinetics, indicative mainly of monolayer chemisorption controlled. Thermodynamic analysis reveals a spontaneous, endothermic, and entropy-driven process. The composite shows outstanding selectivity, with uranyl distribution coefficients at least 2 orders of magnitude higher than those of competing ions. After five adsorption-desorption cycles using 0.1 M HNO₃, 80% of the initial capacity is retained. Crucially, the Cu-Met nanochannels confer broad-spectrum antibacterial performance, suppressing Pseudomonas aeruginosa formation by 98.54%. In natural Bohai Sea water, after 7 days of adsorption, the uranium adsorption capacity is 0.322 mg/g, highlighting its salt tolerance and antifouling resilience. This multifunctional design, marrying strong amidoxime chelation, magnetic recoverability, and MOF-mediated antibacterial action, offers a viable route toward selective, reusable, and biofouling-resistant adsorbents for large-scale uranium harvesting from seawater.

Ionically bonded interfaces are crucial for achieving selective and stable direct seawater electrolysis, yet their vulnerability under corrosive and high-current conditions limits long-term performance. Here, we report a two-dimensional Fe-MOF@PW₈O₂₆.B₂O₃ heterostructured electrocatalyst, synthesized via a solid-liquid interfacial growth strategy, that integrates robust Fe-O-W and tunable Fe-P-W ionic bonds to strengthen interfacial electronic coupling, redox flexibility, and structural integrity. Subsurface B₂O₃ enhances surface hydroxylation via Lewis acid-base interactions, facilitating catalyst assembly and OH^- affinity, while phosphate polyanions at the interface act as electrostatic shields that repel Cl^- ions and modulate the redox environment of Fe active sites. This interfacial configuration enables chlorine-suppressive oxygen evolution with a Faradaic efficiency of 97.93%, achieving a current density of 1.75 A cm^-2 at 2.0 V and stable operation above 1.5 A cm^-2 for over 500 h in alkaline seawater, with an exceptionally low corrosion rate of 0.016 μm per year. NEXAFS and XPS analyses confirm the presence of dual ionic linkages, while DFT calculations reveal their cooperative role in stabilizing the electronic structure and interfacial charge distribution. Beyond hydrogen production, the spent electrolyte is repurposed for CO₂ mineralization, achieving 88.76% conversion to stable carbonates, with cytotoxicity assays confirming reduced environmental toxicity. Together, this study establishes a multifunctional ionically engineered platform for durable, chlorine-free seawater electrolysis and integrated carbon capture, advancing the prospects of circular hydrogen systems.

Mussels, an ecologically diverse group of bivalve molluscs, have attracted attention due to phenomenal adaptability across marine and estuarine environments and an exceptional ability to adhere strongly to wet and dynamic substrata by secreting specialized adhesive structures called byssal threads. These proteinaceous structures, which are secured by sticky plaques, enable mussels to sustain harsh environments and powerful currents. The cuticular covering of byssal thread is mechanically strong but flexible, with reversible metal-ligand coordination, particularly Fe³⁺-DOPA bonds that provide load-dissipating and self-healing properties. The unique combination of different properties, including mechanical, metal-binding, and self-healing, has been attributed to unique proteins synthesized by mussels called mussel foot proteins (mfps) found within the byssus, which is rich in catechol-containing residues such as DOPA. Numerous environmental factors affect the development and functional efficacy of byssus. Motivated by the remarkable properties of mussels, scientists have developed a wide range of bioinspired materials. This review presents an overview of different mussel species as well as structural and functional characteristics of the byssal threads. Besides focusing on their mechanical strength and biocompatibility, this study examines recent advancements in mussel-inspired hydrogels and scaffolds for bone regeneration, motion detection, and wound healing. Further emphasizing unique adhesion chemistry, this review highlights the development of next-generation biomaterials and healthcare technologies, especially smart biosensors and multifunctional theranostic platforms for integrated disease diagnostics and targeted therapy.

Chronic wounds associated with diabetes mellitus exhibit delayed healing primarily due to hypoxia-induced impairment of angiogenesis and persistent inflammation. Recently, microalgae-based hydrogel dressings have emerged as promising candidates for managing diabetic chronic wounds. However, the survival and functional stability of microalgae within hydrogels remain poorly understood, as limited research has focused on developing matrices conducive to algal viability. In this study, we developed a novel hydrogel (HA-gel@CV) tailored to the survival environment of Chlorella vulgaris (CV) to enhance algal viability and accelerate diabetic wound healing. The hydrogel was synthesized through self-assembly using hyaluronic acid (HA) as the scaffold to load CV, sequentially incorporating ceramide, urea, Portulaca oleracea (PO) extract, and nicotinamide solution, with gelation shaped by peach gum polysaccharide (PGP). CV viability in HA-gel@CV was assessed over 5 days by quantifying cell density, total chlorophyll content, and oxygen production. Light and fluorescence microscopy, as well as macroscopic color analysis, confirmed that CV remained stable for more than 7 days and exhibited proliferation within the gel. In vitro studies demonstrated that HA-gel@CV enhanced cell proliferation, migration, and angiogenesis, while in vivo experiments showed reduced inflammation and improved vascular and tissue regeneration in diabetic wounds. In summary, HA-gel@CV represents a multifunctional hydrogel integrating oxygenation, anti-inflammatory, moisturizing, and reparative properties, demonstrating strong potential for treating diabetic chronic wounds.