RSC Advances最新文献

Agents that target the amyloid-beta (Aβ) peptide associated with Alzheimer's disease have seen renewed interest following recent the clinical success of monoclonal antibody therapeutics. Metal complexes are particularly promising for development, given their relative ease of preparation and modular scaffold. Additionally, Aβ has been shown to coordinate endogenous metal ions in solution, while metal complexes can exploit this affinity, thereby modulating the aggregation of the peptide. Herein, a series of five ruthenium(ii)-arene complexes with 1,10-phenanthroline (phen) ligands were prepared and studied for their respective abilities to impact the aggregation of Aβ. Overall, the complex with the 4,7-diamino-1,10-phenanthroline ligand (RuPA) had the greatest impact on Aβ aggregation. Furthermore, this complex also displayed interactions with imidazole in aqueous media, which suggests that coordinate interactions with the peptide occur via histidine. Lastly, RuPA also demonstrated exceptional biocompatibility towards two neuronal cell lines and displayed a lower affinity to human serum albumin in comparison to ibuprofen. Taken together, the primary amine groups on the phen ligand enhanced the anti-Aβ ability of the complex, which is an important structure-activity relationship.

The development of reliable sensing platforms for synthetic food additives remains a critical challenge due to severe matrix interferences that limit selectivity and analytical accuracy. In this work, a multiphysics-guided framework is employed to design a ZIF-67/MWCNT-modified glassy carbon electrode (GCE) for the highly selective electrochemical detection of sunset yellow (SY) in complex food matrices. By integrating experimental electrochemical analysis with COMSOL-based modeling of mass transport, adsorption dynamics, charge transfer, and thermal effects, this study provides a mechanistic basis for material-analyte interactions that govern sensor performance. The ZIF-67/MWCNT hybrid exhibits synergistic surface chemistry, where π-π stacking between the azo-aromatic structure of SY and the graphitic domains of MWCNTs, together with electrostatic interactions with Co²⁺ centers in ZIF-67, yields a high adsorption constant (K _ads = 5.41 × 10⁴ m³ mol^-1) and a dominant surface flux (3.47 × 10^-7 mol m^-2 s^-1), surpassing those of common interferents. The optimized electrode delivers a steady-state current density of 5.22 µA m^-2 at pH 7 and a 5 µm composite layer, while maintaining negligible faradaic contributions from ascorbic acid, citric acid, aspartame, and acesulfame potassium. Parametric simulations reveal robust performance under thermal variations (298-328 K), minimal sensitivity to electrolyte disturbances, and a direct correlation between surface heterogeneity and current attenuation. Model validation against experimental electrochemical impedance spectroscopy yields a low RMSE (0.0621), confirming predictive accuracy. These findings demonstrate how multiphysics analysis can rationally guide electrode engineering, offering a powerful design strategy for next-generation electrochemical sensors. The proposed platform provides a selective, sensitive, and scalable solution for trace-level SY detection, underscoring its relevance for food safety monitoring and real-sample analysis.

Selenium-copper bimetallic nanoparticles (Se-Cu BMNPs) were synthesized using metabolic extracts from the marine bacterium Bacillus licheniformis LHG166 isolated from the Red Sea. UV-Vis spectroscopy showed maximum absorption at 208 nm. FT-IR analysis revealed bacterial proteins and polysaccharides from the bacterial extract as reducing and capping agents, showing an Amide I shift to 1646.28 cm^-1 and new Cu-O/Se-O stretching at 470.34 cm^-1. XRD patterns confirmed the presence of both orthorhombic and cubic phases of CuSe, with an average crystallite size of 27.2 nm. TEM showed spherical morphologies of 20-120 nm diameter. EDX confirmed Cu : Se atomic ratio near 1 : 1 (7.1 at% Cu, 7.5 at% Se). DLS measured the hydrodynamic diameter of 84 nm (PDI 0.26) with a zeta potential of -24.11 mV. Antioxidant testing showed DPPH scavenging up to 96.1% at maximum concentration with an IC₅₀ of 4.1 µg mL^-1 vs. ascorbic acid's 3.1 µg mL^-1, and ABTS scavenging reached 94.6% with an IC₅₀ of 10.73 µg mL^-1 compared to 2.55 µg mL^-1 for ascorbic acid. Anti-inflammatory assessment demonstrated COX-1 inhibition up to 97.3% (IC₅₀ = 7.05 µg mL^-1) and COX-2 inhibition reaching 95.3% (IC₅₀ = 12.11 µg mL^-1) vs. celecoxib's IC₅₀ values of 5.93 and 4.51 µg mL^-1, respectively. Antimicrobial screening via agar well diffusion showed inhibition zones of 28 mm for B. subtilis, 24 mm for E. faecalis, and 27 mm for C. albicans. Broth microdilution revealed MIC values ranging from 15.62 µg mL^-1 (B. subtilis, C. albicans, C. tropicalis) to 125 µg mL^-1 (S. aureus), with MBC/MFC values between 15.62-250 µg mL^-1, yielding ratios of 1.0-4.0, indicating bactericidal activity. Gram-negative bacteria required 31.25-62.5 µg mL^-1 for inhibition and 62.5-125 µg mL^-1 for complete killing, while A. niger showed complete resistance. Biofilm inhibition through microtitre plate assays demonstrated concentration-dependent effects, with 75% MBC achieving over 90% inhibition for most organisms (C. albicans 96.09%, B. subtilis 93.76%, E. coli 91.59%), though S. aureus required higher concentrations (84.33% at 75% MBC). These results demonstrated that marine bacterial metabolites produce biocompatible Se-Cu BMNPs with potent antioxidant, anti-inflammatory, antimicrobial, and antibiofilm properties suitable for biomedical applications.

Dental caries and associated oral infections require biomaterials that promote remineralization while controlling bacterial growth and maintaining cytocompatibility. In this study, a sol-gel-derived silica-based 58S bioactive glass was investigated as a carrier for Andrographis paniculata (AP) extract (AP@58S-2) for antibacterial dental applications. Spherical 58S particles were synthesized via a two-step sol-gel route, yielding an amorphous glass with a high specific surface area of 786.3 m² g^-1 and mesopores distributed in the 1.49-2.14 nm range, as confirmed by SEM, TEM, XRD, and nitrogen adsorption analyses. Compared with glass prepared by a one-step method, the two-step 58S exhibited a more uniform morphology and moderate pH variation during immersion, which is favorable for cellular compatibility. The mesoporous structure enabled efficient AP extract loading (∼65%, corresponding to ∼10.6 µg extract per mg glass) and supported sustained release of andrographolide, reaching approximately 70% cumulative release within 24 h under simulated physiological conditions. In vitro cytocompatibility assays demonstrated that AP@58S-2 maintained hMSC viability above 90% across the tested extract concentrations. Antibacterial evaluation against Streptococcus mutans revealed enhanced efficacy for AP@58S-2 compared with the unloaded bioactive glass, with a minimum inhibitory concentration of 1.5 mg mL^-1 and bactericidal behavior indicated by an MBC/MIC ratio of 1.33, together with a time-dependent reduction in biofilm viability. AP@58S-2 demonstrated potent antioxidant activity through effective DPPH and ABTS radical scavenging and significantly reduced nitric oxide generation in LPS-stimulated RAW 264.7 cells. These results indicate that morphology-controlled 58S bioactive glass can function as an effective carrier for plant-derived bioactive compounds, providing combined mineralization-related bioactivity, antibacterial effects, and antioxidant functionality. This integrated approach is relevant for dental applications where infection control and oxidative stress management are required alongside tissue regeneration.

Preparation and characterization of a series of oligo(ethylene glycol)methylether functionalized alkynyl gold(i) complexes capped with AuPPh₃ (1a-1d) or dppfAu₂ (dppf, 1,1'-bis(diphenyphosphino)ferrocene) (2a-2d) have been accomplished. The structures of 1b and 1c were established by X-ray crystallography. Their in vitro antitumor activities were measured by the CCK8 method against A549 and HeLa cells. The studies indicated that the cytotoxic activity in vitro was fine-tuned by modification of both the gold(i) centers and the oligo(ethylene glycol)methylether ancillary ligands. Compared to the dppfAu₂ series, the AuPPh₃ series showed better cytotoxicity. Especially, complex 4-(OCH₂CH₂OCH₂CH₂OCH₃)C₆H₄C[triple bond, length as m-dash]CAuPPh₃ (1d) displayed strong anticancer activity toward both cancer cells due to the strong inhibition of thioredoxin reductase (TrxR).

Biochar (BC) and biostimulants, such as fulvic acid (FA), have proven to have potential in composting. They have been shown to reduce nitrogen loss and enhance the quality of compost, benefitting the composting of manure and straw. However, the synergistic effects of BC and FA on composting remain largely unelucidated. The present study evaluated the individual and synergistic effects of BC and FA on the composting of chicken manure mixed with straw. Results demonstrated that BC + FA significantly reduced ammonia (NH₃) volatilization by 48.11% through the composting process. In addition, BC + FA increased the accumulated temperature and pH and reduced the electrical conductivity of composts. Regarding the final products, the BC + FA treatment increased the contents of total nitrogen and dissolved organic carbon and improved the germination index (GI) by 50%. Concurrently, FA and BC + FA increased the content of humic substances by 12.6% and 12.8%, respectively. The ratio of humic acid to FA increased from 8.2% to 44.9% following the BC + FA treatment compared to that in the control. Furthermore, BC enhanced the fluorescence and humification indices of the composts. Besides, it was revealed that the functional groups present on the surfaces of BC and FA + BC were associated with intermolecular polymerization and aromatization. The Mantel test confirmed that BC + FA effectively reduced the NH₃ emissions of this process and enhanced the quality and GI, probably through stimulating the directional transformation of organic matter. This study systematically evaluated the effect of BC and FA in a composting trial and offered a promising and comprehensive strategy for the effective resource utilization of manure and straw.

The pervasive corrosion of mild steel in acidic media poses a significant challenge in various industrial applications. While existing synthetic corrosion inhibitors are effective, their high cost and environmental toxicity necessitate the development of more sustainable alternatives. In this study, we present a novel approach to corrosion mitigation employing a porous nanocarbon synthesized from mango kernels, a sustainable source of agricultural waste. The CNS inhibitor was synthesized via pyrolysis at 800 °C, yielding a high surface area (1090.2 m² g^-1) as confirmed by BET analysis. FE-SEM revealed a well-developed spherical morphology with an average particle size of 60-70 nm. The corrosion inhibition efficiency of CNS was evaluated for mild steel in 1 M HCl using a combination of electrochemical techniques, including open circuit potential, potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy. The CNS derived from waste mango kernels, exhibited excellent inhibition performance, achieving an efficiency of up to 87.1% at 800 ppm. PDP results revealed a mixed-type inhibition mechanism with suppression in both anodic and cathodic reactions. The thermodynamic parameter, adsorption free energy () of about -20.0 kJ mol^-1, indicates a spontaneous process and predominantly physical adsorption. Adsorption behavior was consistent with the Langmuir isotherm model. Surface analyses using SEM, EDS, optical profilometry, and water contact angle measurements corroborated the formation of a protective inhibitor film on the steel surface. These findings highlight the potential of bio-waste-derived materials as a sustainable and environmentally benign corrosion inhibitor for mild steel in acidic environments.

Metal halide perovskites have shown remarkable potential in photovoltaic and optoelectronic applications due to their excellent light absorption, high defect tolerance, and long carrier diffusion lengths. In this study, we systematically investigate copper-based metal halides and introduce a hypophosphorous acid-assisted mechanochemical ball milling strategy to construct highly stable copper halide systems. Leveraging the broadband emission characteristics of self-trapped excitons (STE), we explore the controlled synthesis and optoelectronic applications of these materials. Using DPCu₄Br₆ (DP = p-phenylenediamine) as a representative compound, we achieved outstanding optical performance, including broadband emission (FWHM = 120 nm), minimal reabsorption, ultrahigh photoluminescence quantum yield (PLQY = 98.38%), and a long exciton lifetime of 47.62 µs. Remarkably, the material retained over 80% of its PLQY after six months of exposure to ambient air, demonstrating superior environmental stability. Based on these results, a 6 × 6 cm² luminescent solar concentrator (LSC) was fabricated, achieving an optical conversion efficiency (η _opt) of 12.43%, and successfully integrated with electrochromic smart windows to enable self-powered light modulation through a synergistic system design.

Saussurea costus (S. costus), a medicinal plant widely utilized in traditional Ayurveda, Chinese, and Tibetan medicine, is rich in pharmacologically active compounds, including sesquiterpene lactones, flavonoids, phenolics, and essential oils. Despite its reported antimicrobial, anti-inflammatory, antioxidant, anticancer, and immunomodulatory activities, clinical translation of S. costus remains hindered by its low bioavailability and off-target effects. This review explores the use of nanosystems to address these limitations and enhance the biological performance of S. costus extracts. Metal-based nanoparticles (silver, copper, palladium, magnesium oxide) and other nano-formulations, including polymeric, lipid-based, and inorganic nanoparticles, detailing their synthesis, characterization techniques, and biomedical applications. The integration of S. costus into nanosystems is shown to improve cellular uptake and facilitate prolonged release and superior therapeutic outcomes as supported by several in vitro and in vivo studies. This review highlights the incorporation of Saussurea costus into different nanosystems towards the development of effective nanotherapeutics.

Herein, we investigate perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) as a linker in Zr-clusters. The photostable, 3D metal-organic nanomaterial obtained by a solvothermal synthesis procedure in the presence of formic acid as modulator, named ZIPER, shows strong absorption in the visible (400-560 nm) and an intense photoluminescence (PL) in the 600-700 nm range. PL quenching experiments strongly indicate that the ZIPER excited state (ZIPER*) behaves primarily as a strong oxidant and a mild reductant with redox couples E(ZIPER*/ZIPER˙^-) = 1.8-1.2 V and E(ZIPER˙⁺/ZIPER*) = -0.44--0.48 V (vs. NHE). Amine quenching of ZIPER* PL led to a strong reductant (ZIPER˙^-) with E(ZIPER/ZIPER˙^-) <-0.6 V vs. NHE. This reactivity was exploited to drive the reductive dehalogenation of model polychlorinated compounds, such as carbon tetrachloride and trichloroacetic acid, through visible-light photoredox catalysis in aqueous suspension. In contrast, under air-saturated conditions, the system predominantly produces substantial amounts of H₂O₂. A detailed analysis of the results suggests that photoexcitation of the organic linkers is followed by electron transfer to the Zr cluster. Charge-separated states are mainly stabilized in the presence of suitable electron donors or acceptors; otherwise, the system relaxes radiatively, emitting strong orange fluorescence.