RSC Advances最新文献

Despite its clinical success, conventional deep-brain stimulation (DBS) for Parkinson's remains limited by its invasive nature. To overcome this, we engineered ZnO@polydopamine (ZnO@PDA) nanocomposites as a non-invasive neurotherapeutic platform. By leveraging rational nanostructure design, ZnO@PDA enabled reversible blood-brain barrier (BBB) opening via a photothermal mechanism, thereby permitting targeted nanoparticle delivery. Upon reaching the brain, nanocomposites harness ultrasound-driven electrical stimulation to precisely modulate neuronal circuits, thus offering a groundbreaking alternative to traditional DBS. Simultaneously, their potent antioxidant activity neutralizes reactive oxygen species, suppresses microglial overactivation, and mitigates pathological α-synuclein aggregation. In vivo studies demonstrated that laser-triggered ZnO@PDA treatment significantly restored dopaminergic neuronal function and improved motor coordination, whereas ultrasound-based protocols alone were less effective owing to insufficient BBB penetration. Our work presents a "penetration-accumulation-stimulation" cascade strategy, delivering a transformative approach to non-invasive treatment of neurodegenerative disorders.

Immunoassays require high sensitivity and specificity for the detection of low-abundance analytes in complex matrices such as blood plasma. The use of functionalized magnetic beads can increase assay sensitivity by selectively binding and concentrating target analytes, facilitating their separation. However, magnetophoretic bead collection still represents a critical bottleneck. It must be performed repeatedly throughout sequential mixing, washing, and dilution steps, which is time-consuming and prone to cumulative bead loss, ultimately reducing assay performance. Here, we present a comprehensive framework for the design of magnetic bead collection systems integrated on a rotating microfluidic (lab-on-a-disc) platform. We establish a finite-element multiphysics model of bead collection that couples magnetophoretic forces, centrifugal effects, magnetophoresis-induced convection, and cooperative bead motion. The model is experimentally validated on a dedicated setup using Dynabeads M270. Increased bead collection speed is attributed to convection-enhanced transport and bead aggregation into chains. The model enables systematic investigation of geometric parameters, fluid viscosity, bead properties, and rotational protocols, as well as the efficiency of various permanent magnet configurations. We investigate magnet arrangements, vary the rotational speed between 300 and 800 rpm, and the magnet-fluid distance between 2 and 6 mm. Within this range, our results show, for any targeted collection fraction, a linear decrease in collection time with increasing magnet-fluid distance and an exponential reduction with decreasing rotational speed. Beyond performance gains, this predictive in silico framework reduces the reliance on costly trial-and-error optimization and can accelerate assay development.

A novel panel of diselenide-linked imidazolone derivatives was synthesized and biologically profiled, revealing a promising new chemotype with broad-spectrum anticancer activity. Among the series, compounds 6b, 6d, and 6g demonstrated exceptional growth-inhibitory (GI) potency, achieving GI% values of 80.32%, 79.24%, and 86.40%, respectively-substantially outperforming doxorubicin (61.49%). Notably, 6g emerged as the lead candidate, exhibiting robust cytotoxicity across diverse cancer models with IC₅₀ values of 6.49 µM (PC3), 6.58 µM (MCF7), 5.38 µM (A549), and 7.25 µM (HCT₁₁₆). Mechanistic studies in A549 cells indicated that 6g simultaneously modulates multiple oncogenic pathways: it markedly downregulated CDK2, CDK4, and CDK6 (1.57-4.12 fold), while upregulating caspase-3, caspase-8, and caspase-9 (1.60-1.64 fold), collectively supporting its dual action on cell-cycle blockade and apoptotic activation. Furthermore, a 1.68-fold reduction in VEGFR-2 expression underscores its additional anti-angiogenic potential. Flow cytometry corroborated these findings, revealing a dramatic S-phase arrest, with the S-phase population rising from 4.61% to 42.09% upon treatment. Several other analogues, including 6d, 6e, 6i, and 6j, also displayed potent cytotoxicity (IC₅₀ < 10 µM), highlighting the broader therapeutic relevance of this scaffold. Collectively, these data position 6g as a compelling multi-target anticancer lead that integrates apoptosis induction, cell-cycle regulation, and angiogenesis suppression-supporting its potential for development as a next-generation broad-spectrum anticancer agent.

Hierarchical ZSM-5 zeolites were synthesized by one-pot methods utilizing water-soluble polymers-polyvinylpyrrolidone (PVP) and polyethylene glycol (PEG)-and were compared with a desilicated (DS/ZC) typical microporous ZSM-5 (ZC). Thorough evaluation utilizing XRD, FT-IR, NH₃ physisorption, SEM and TEM, ICP-OES, NH₃-TPD, and TGA demonstrated that PVP-templated ZSM-5 (PVP/ZC) displayed distinct mesoporosity while maintaining its inherent microporous structure, resulting in a balanced allocation of weak and strong acid sites. All catalysts were assessed in the methanol-to-aromatics (MTA) reaction at 400 °C, with a weight hourly space velocity (WHSV) of 5 h^-1 and atmospheric pressure (time on stream = 3 h), resulting in over 99.5% methanol conversion. PVP/ZC attained the highest BTX selectivity of 51.3% and an overall aromatic selectivity of 60.1%, due to its uniform mesoporosity, reduced diffusion pathways along the b-axis, and optimized distribution of acid sites, which collectively minimized secondary C₉₊ formation (8.8%) and coke deposition (3.27 wt%). The findings indicate that water-soluble polymer templates, specifically PVP, facilitate the customized synthesis of hierarchical ZSM-5 catalysts, which improve BTX production and stability in the MTA process, providing a cost-effective and environmentally friendly alternative to conventional templating and post-synthetic treatments.

A nanocomposite injectable hydrogel based on chitosan (CS), hydroxypropyl methylcellulose (HPMC), and fluorapatite nanoparticles (Nano-FA) was developed and evaluated for its bone regenerative potential following tooth extraction in diabetic rat models. Nano-FA was synthesized via a co-precipitation method and incorporated into a CS-HPMC hydrogel matrix to obtain a homogeneous CS-Nano-FA-HPMC composite. Forty adult male albino rats underwent bilateral extraction of the lower first molars and were randomly divided into four groups: untreated control, CS, Nano-FA, and CS-Nano-FA-HPMC. Bone healing was assessed after 2 and 6 weeks using histological, immunohistochemical, ultrastructural, histomorphometric, biochemical, and energy-dispersive X-ray analyses. The CS-Nano-FA-HPMC group exhibited significantly enhanced bone regeneration compared with the other groups, as evidenced by increased new bone formation, a higher number of entrapped osteocytes, and well-defined bone remodeling lines. Histomorphometric and statistical analyses confirmed that this group achieved the highest percentage of new bone area at both time points. In addition, inflammatory markers were markedly reduced, while osteogenic markers, including alkaline phosphatase and osteocalcin, were significantly elevated in the nanocomposite-treated group. These findings demonstrate that although CS and Nano-FA individually exhibit osteoconductive properties, their combination within a CS-Nano-FA-HPMC hydrogel provides superior regenerative performance, offering a promising strategy for enhancing bone healing under compromised diabetic conditions.

This work involves the fabrication and comprehensive characterization of flexible polyvinyl chloride (PVC)/thermoplastic polyurethane (TPU)/BaSnO₃/Sn₂O₃ (BSO/SO) nanocomposites, with a focus on optimizing their structural, dielectric relaxation, and optical properties for energy storage and optoelectronic applications, and they were synthesized by co-precipitation and drop-casting procedures. The distinctive systems were examined using XRD, FTIR, HRTEM, and FESEM techniques, including the structural integrity of blends and nanocomposites. A BaSnO₃/Sn₂O₃ (BSO/SO) nanocomposite has been effectively integrated into the PVC/TPU blend, as demonstrated by microstructural characterization using XRD, EDX, and ATR-FTIR tools. Supplementation with nanoparticles elevated the crystallinity, improved interfacial contact, and optimized the filler distribution. The incorporation of BSO-SO nanofiller notably modifies the dielectric relaxation characteristics of PVC/TPU blends via mechanisms that include interfacial polarization, limited polymer mobility, and improved charge carrier dynamics, demonstrating a dielectric constant of 120, a twelvefold increase at higher concentrations of nanofiller at low frequencies. The amount of nanofiller in the PVC/TPU-BSO-SO composites greatly influences how they transmit and reflect light, improving their clarity, ability to block UV rays, and flexibility in terms of the optical properties. Pronounced reductions of the direct and indirect optical band gaps are seen. The changes in band gaps might be due to more disorder, changes in crystal structure, and the possible clumping of nanoparticles. The resulting nanocomposites combine flexibility with tunable dielectric and optical properties, positioning them as strong candidates for use in flexible energy storage, UV blocking, and optoelectronic applications.

A novel K⁺/Cu²⁺ co-chelated diastereoselective Friedel-Crafts reaction with chiral N-sulfinyl ketimines has been developed for the synthesis of chiral bisindoles. The method exhibits broad substrate compatibility and high stereoselectivity. The synthesized bisindoles show significant cytotoxicity against tumor cell lines such as MG63 and HepG2, with Compound 29 demonstrating selective inhibitory effects on osteosarcoma cells. This protocol provides a useful strategy for the efficient construction of chiral bisindoles. The potential of these compounds in cancer therapy was also highlighted.

Fluorine-containing molecules have attracted increasing attention in pharmaceutical chemistry owing to their unique physicochemical properties. As there are no known examples of naturally occurring fluorinated organic molecules, fluorination of organic molecules gains significant interest in organic synthesis. Terpenoids represent one of the largest and most structurally diverse classes of natural products, exhibiting a broad range of pharmacological effects. Fluorination of terpenoid scaffolds has therefore become an active area of research aimed at enhancing or diversifying their bioactivity profiles. This review summarizes the synthetic strategies developed for the preparation of fluorinated terpenoids across different subclasses, including mono-, sesqui-, di-, tri-, and tetranor-terpenes.

Glass-composite sealants are critical for reliable high-temperature sealing in planar solid oxide fuel cells (SOFCs). This work investigates the influence of ZrO₂ on the sintering and crystallization kinetics of silicate-based glass-composite sealants. Dilatometry analysis reveals ZrO₂ promotes earlier densification and extends the sintering stage, with 200 nm particles exhibiting the strongest effect. Viscosity-temperature relationships, derived from differential scanning calorimetry (DSC) and the Vogel-Fulcher-Tammann model, indicate ZrO₂ increases viscosity by filling free volume, while excessive 50 nm ZrO₂ (>30 wt%) reduces viscosity due to nanoparticle agglomeration. Scanning electron microscopy (SEM) observations confirm that 200 nm ZrO₂ forms a rigid percolation framework, improving local sintering and promotes pore closure. X-ray diffraction analysis (XRD) indicates the incorporation of ZrO₂ does not alter the crystalline phases composition. Crystallization kinetics analysis shows ZrO₂ acts as heterogeneous nucleation centers, promoting diopside formation. For 2 µm and 50 nm ZrO₂, the crystallization activation energy increases with doping up to 30 wt% but decreases thereafter due to agglomeration-induced energy localization, whereas 200 nm ZrO₂ yields a continuous reduction, reflecting a balance between surface activity and dispersion stability. These findings provide insights for designing glass-composite sealants with optimized microstructures and improved performance in SOFC applications.

Natural pigments and dyes provide a rich interface between biodiversity and chemistry, offering structurally diverse molecules with distinctive reactivity and bioorganic relevance. These compounds occur in plants, marine organisms, fungi, bacteria, insects, birds, animals, and mineral sources. They encompass major chemical classes such as carotenoids, tetrapyrroles and their degradation products. Owing to their biocompatibility and natural origin, these pigments are increasingly explored as safer alternatives to synthetic dyes and as functional ingredients in food, cosmetic, textile, and pharmaceutical applications. In recent years, these natural pigments have gained significant attention as bioactive molecules with antioxidant, anti-inflammatory, antimicrobial, antiviral, anticancer, neuroprotective, hepatoprotective, and immunomodulatory potential, exhibiting beneficial effects in preventing chronic disorders like diabetes, cardiovascular and degenerative eye diseases. This review provides an integrated examination of biodiversity, chemical classes, biosynthetic logic, structure-activity relationships, and biological properties of these natural pigments and dyes. Key challenges related to chemical stability, bioavailability, and scalable production are discussed, together with emerging biotechnological strategies designed to enhance their stability and sustainable supply.