RSC Applied Interfaces最新文献

We studied the surface properties of Ga-Cu based liquid metal alloys - a promising material system for supported catalytically active liquid metal solutions (SCALMSs). The impact of Cu dilution in the (liquid) Ga matrix is in-detail investigated by X-ray and UV photoelectron spectroscopy (XPS/UPS) and machine-learned-force field (ML-FF) calculations. With decreasing Cu content, microscopic and macroscopic Ga-Cu model samples exhibit a shift of the Cu 2p core level line to higher binding energies (E _b) as well as a correspondingly shifted and narrowed d-band with respect to pure Cu, which we ascribe to site isolation. To study the property evolution of Ga-Cu at SCALMS reaction conditions, i.e., where Cu is present in liquid Ga, additional XPS measurements were performed between 100 and 500 °C. The observed Cu 2p shift to lower E _b is tentatively ascribed to changes in the local environment with increasing temperature, i.e. bond elongation, which is corroborated by ML-FF simulations; the increased Cu surface content at low temperatures is attributed to the presence of crystallized Cu-rich intermetallic compounds, as evidenced by transmission electron microscopy images. In an attempt to generalize the findings for filled d-band transition metals (TMs) in liquid Ga, first results on Ga-Ag and Ga-Au model systems are presented. The observed insights may be another step of paving the way for an insight-driven development of low-temperature melting liquid metals for heterogeneous catalysis.

The surfaces of polyamide-based low-pressure reverse osmosis (RO) membranes were modified with poly(2-methoxyethyl acrylate) (PMEA) via surface-initiated atom transfer radical polymerization for the first time to achieve low-fouling characteristics. The successful grafting of PMEA was demonstrated by attenuated total reflectance Fourier-transform infrared spectroscopy and zeta potential measurements. The grafting amount could be tuned from 0.020 to 0.23 mg cm⁻² by changing the grafting time. The modified membranes maintained their salt rejection performances with slight reductions of pure water permeability especially when the grafting amount was smaller than 0.05 mg cm⁻². This result indicated that the grafted PMEA had almost no effect on salt rejection but slightly increased the permeation resistance. Compared with unmodified membranes, the modified membranes were found to exhibit low fouling against a variety of organic substances, such as lysozyme, guar gum and tetraethylene glycol monooctyl ether. The results indicate that surface modification of a low-pressure RO membrane with PMEA is a feasible method to obtain a membrane with low-fouling characteristics.

Metal–organic frameworks (MOFs) built from zinc ions and 2-methylimidazole (HmIM) are widely explored carriers for gene delivery. Although preliminary reports show phase-dependent properties, often studies label distinct crystalline phases as “ZIF-8” and overlook how routine washing steps influence the property-to-function relationship. Here, we examine in depth how solvent history tunes the crystal phase and biological performance in plasmid DNA (pDNA) encapsulated in Zn–mIM carriers. An aqueous biomimetic mineralization at 25 °C (HmIM : Zn²⁺ = 4 : 1) yields defect-rich sodalite (sod) ZIF-8 with an ∼80% encapsulation efficiency of the input plasmid and four times the loading obtained from an identical ethanolic synthesis. Post-synthetic solvent washes or aging govern phase transformations: media containing ≥70% water trigger a solution-mediated transformation into a carbonate–imidazolate framework (ZIF-C), whereas absolute ethanol stabilizes sod ZIF-8 topology. Despite the extensive recrystallization processes into chemically distinct solids, pDNA loss remains ≤12% for sod → ZIF-C and ≤20% for ZIF-C → sod transformation. The green fluorescent protein (GFP) assays confirm that the recovered pDNA retains full transcriptional activity. Comparative cytotoxicity tests on PC-3 cells show that water-aged ZIF-C sustains ≥85% viability and superior colloidal stability, while ethanol-stabilized sod-ZIF-8 possesses a higher pDNA loading and an on-demand burst release upon first contact with water. By examining how post-processing with ethanol/water yields pure sod, mixed sod/ZIF-C, and pure ZIF-C carriers, this work provides the first solvent-phase guide for MOF gene carriers and establishes simple washing protocols as tools to tune release kinetics, stability, and biocompatibility without altering the ZIF precursors or the reaction temperature. By enabling phase-engineered DNA@ZIF carriers with predictable gene-delivery performance, this study advances MOF-mediated nucleic acid therapies toward reproducible biomedical applications.

The increasing prevalence of multidrug-resistant (MDR) bacteria and aggressive breast cancers such as triple-negative breast cancer (TNBC) poses a significant challenge to current therapeutic strategies, necessitating the development of novel, biocompatible and multifunctional materials. In this study, a bio-nanocomposite matrix of Eri silk fibroin–zinc oxide (ESF@ZnO) has been successfully synthesized and characterized to explore its potential for antibacterial and anticancer applications. XRD, FTIR, UV-vis, FESEM and TEM demonstrated the successful integration of ZnO within the ESF matrix. FESEM of the ESF@ZnO composite revealed a heterogeneous surface morphology with ZnO nanoflakes embedded within the silk fibroin matrix. TEM further confirmed the incorporation of crystalline ZnO structures into the amorphous network, while SAED patterns displayed both sharp diffraction rings from ZnO and diffuse halos from ESF, validating the formation of a hybrid organic–inorganic nanocomposite. The antibacterial activity of ESF@ZnO was evaluated against Escherichia coli and Bacillus subtilis with an inhibition zone of 14.8 ± 0.15 mm and 13.2 ± 0.14 mm, respectively. Furthermore, ESF@ZnO exhibited significant anticancer activity against 4T1 (mouse breast cancer) and MDA-MB-231 (human triple-negative breast cancer) cell lines, with IC₅₀ values of 84.06 ± 21.13 and 29.76 ± 13.46 μg mL⁻¹, respectively. A dose-dependent reduction in cell viability and statistically significant cytotoxic effects (p < 0.001) were observed, confirming its effectiveness in inducing cancer cell death. These results highlight ESF@ZnO as a promising bio-nanocomposite for future antibacterial and anticancer applications.

The skin is a critical barrier protecting internal organs from external threats, including pathogens, while also regulating body temperature. However, when pathogens invade this barrier, the integrity of the skin can be disturbed, leading to infection and disease. Fungal infections are increasing, as is fungal resistance to existing drugs, posing significant threats to public health. Here, we developed an antifungal polypeptide-based formulation for topical treatment of subcutaneous fungal infections by incorporating ε-poly-L-lysine (EPL), which has antifungal activity, with recently developed ionic liquid-in-oil formulations (IL/Os). Our results indicate that the IL/Os showed efficacy in compromising the integrity of the stratum corneum in a mouse skin model and prevented the electrostatic interaction of EPL with the SC surface. They allow the EPL to penetrate the skin, and prevent it aggregating, thus enabling it to reach the infecting fungus. EPL-loaded IL/Os demonstrated strong activity against Trichoderma viride (phylum Ascomycota) growing beneath skin. After storage at 25 °C for 28 days, EPL-loaded IL/Os retained antifungal activity similar to that of freshly prepared samples. These findings highlight the potential of EPL-loaded IL/Os for application in topical antifungal treatments.

Nanoparticles exhibit unique properties in optics, electricity, and other fields that differ from those of macroscale materials. Further assembling these functional nanoparticles may generate attractive physicochemical characteristics due to their collective properties. Different assembly structures result in diverse properties. Therefore, precise control over nanoparticle positioning remains a research hotspot, with numerous notable breakthroughs reported in the methodologies investigated. Recently, DNA emerged as a crucial structural material based on its exceptional programmability, addressability, and specific binding capabilities. Leveraging these excellent properties, DNA-functionalized nanoparticles can be accurately positioned at the nanoscale in accordance with predetermined spatial patterns. This capability facilitates the development of novel functionalities and significantly advances the programmable assembly of nanoparticles to a higher degree of sophistication. In this review, we present a systematic survey of the synthesis, functionalization, and assembly methodologies of nanoparticles, alongside an assessment of their current developmental status. Specifically, we systematically introduce several widely employed or potentially advantageous techniques for nanoparticle synthesis and summarize various categories of surface ligands that preserve the nanoparticle physicochemical properties. Based on the most representative DNA ligands, we present a discussion on the methodology and potential applications of DNA-mediated programmed assembly. Furthermore, we have outlined prospective directions and viable strategies for their future advancement.

Analog resistive switching characteristics are recognized as more suitable for neuromorphic computing due to their gradual change in resistance states, energy efficiency, and inherent parallel processing capabilities. The analog switching behaviors are primarily influenced by the switching medium, particularly materials exhibiting mixed ionic and electronic conductivity. In this study, a copper sulfide-based memristive device was fabricated using the chemical bath deposition (CBD), with copper as the active electrode. The CBD-grown copper sulfide is polymorphic in form (Cu_2−xS) as evident from X-ray photoelectron spectroscopy (XPS) and energy dispersive spectroscopy (EDS) studies. The carrier concentration calculated using Mott–Schottky plots is of the order of 10¹⁹ cm⁻³. The device initially demonstrates digital resistive switching behavior, characterized by an ON–OFF resistance ratio of ∼10⁴. Moreover, the device exhibits multilevel data storage capabilities, which can be controlled by adjusting the current compliance during the switching process. Further, the device exhibits analog resistive switching behavior with modulation of the switching parameters such as the applied voltage and voltage sweep rate. The temperature dependent switching studies indicate non-filamentary switching characteristics, which are attributed to the trapping and de-trapping of charge carriers at vacancy or trap sites, coupled with the migration of Cu⁺-ions from the top copper electrode.

The global burden of cardiovascular diseases has been a driving force for a multitude of medical innovations in the biomedical sector, resulting in the creation of various life-saving implants and devices to alleviate patients' suffering. Despite these advancements, many devices remain susceptible to early failure due to complications during integration within the host body. One of the most common causes is the formation of thrombi due to undesired interactions between blood and the artificial surfaces of implanted devices. To address this issue, modern implants are engineered to exhibit surface properties that promote the formation of an endothelial monolayer, often involving surface biochemical functionalization with cell-adhesive coating agents. In this study, we developed a biopolymeric adhesive based on cold-water fish gelatin (cfGel), a non-mammalian cell-adhesive polymer with numerous advantages over its mammalian counterparts. Inspired by the excellent wet adhesion of mussels, cfGel was functionalized with thiourea-catechol (TU-Cat) groups, resulting in the functional biopolymer (cfGel-TU-Cat) capable of stably adhering to surfaces without the need for additional crosslinking. As proof of concept, cfGel-TU-Cat was demonstrated to promote both the adhesion and proliferation of human umbilical vein endothelial cells (HUVECs) and to support the formation of confluent endothelial monolayers, thus demonstrating its potential as a coating agent for cardiovascular devices.

NiCo₂O₄/ZnO_x (x = 0.3 and 0.05) composites were prepared by a precipitation method and characterized using various analytical methods. The hexagonal wurtzite structure of the ZnO phase was retained after integration with NiCo₂O₄ due to the high crystallinity of ZnO. Through the multi-electron reduction of oxygen, the carrier trapping/detrapping of Co²⁺/Co³⁺ was quantitatively predicted to investigate the electron-transport process. As evidenced by its zeta potential (−52.5 mV), NiCo₂O₄/ZnO@0.05 has a higher adsorption capacity than ZnO, NiCo₂O₄ and NiCo₂O₄/ZnO@0.3. The improved photocatalytic activity of NiCo₂O₄/ZnO@0.05 corresponds to its broader light absorption. Besides, photoluminescence spectra suggested that NiCo₂O₄/ZnO@0.05 efficiently increased the rate of photoinduced electron generation and decreased the transfer resistance. The enhanced activity can be ascribed to the electrostatic adsorption between NiCo₂O₄/ZnO@0.05 and MB⁺ dye, with the optimal rate observed at pH 7. The oxidation potential of hydroxyl free radicals in an aqueous medium is substantially influenced by pH, which in turn may suppress the photocatalytic efficiency. Consequently, the generation of the hydroxyl free radicals in an aqueous medium is limited under both acidic (pH 3) and alkaline (pH 10) conditions. Furthermore, the influence of active species was evaluated by conducting trapping experiments to understand the possible photocatalytic mechanism. Liquid chromatography mass spectroscopy technique coupled with UV-visible absorption spectroscopy was used to analyze the degradation product. Results suggested that the removal of methyl groups from the molecule starts with the degradation of the MB dye.

Accurate measurement of ultrathin film thickness is of significant importance in both scientific research and industrial applications. In this study, a neutron capture reaction was successfully employed to measure the thickness of ultrathin Cu films (∼nm) as well as applied to determine the thickness of materials in the semiconductor industry, specifically Si₃N₄ films. The method was demonstrated to be non-destructive and applicable to several different films. Finally, a methodology is proposed to guide the experimental design for thickness measurement. This suggests that the nondestructive method provides a novel approach for measuring thin film thicknesses ranging from the nanoscale to the microscale.