Search Results (1,393)

Conventional biosensor coatings face considerable challenges in reconciling high loading capacity, antifouling performance, and long-term stability. Metal–organic frameworks (MOFs), with their ultrahigh surface areas, tunable pores, and abundant unsaturated metal sites, have become important functional coating materials for advanced sensing interfaces. This review focuses on interface engineering strategies for MOF-based biosensor coatings and systematically compares three core construction approaches, namely defect engineering, MOF-on-MOF heterostructures, and interface-assisted fabrication, examining their distinct interfacial regulation logics and applicability under engineering constraints including substrate compatibility, film uniformity, and scalability. The multifaceted interfacial roles of MOF coatings are then categorized across electrochemical, photoelectrochemical, colorimetric, optical fiber, and dual-signal biosensors, covering enrichment-confinement, catalytic transduction, biorecognition protection, and smart gating. Notably, most reported systems remain at the proof-of-concept stage, with insufficient validation in complex biofluids, ambiguous signal transduction mechanisms, and a notable deficiency in systematic assessments of coating adhesion and durability. Future efforts should focus on establishing standardized failure evaluation protocols, adopting AI-driven rational design, and advancing toward multi-target integrated and flexible wearable platforms to bridge the gap between laboratory research and practical diagnostic applications. Full article

Renewable energy can be harvested from salinity gradients using reverse electrodialysis (RED); however, the open-circuit voltage and power output of this process can be significantly reduced by multivalent ions and natural organic matter found in natural waters. In this work, a tailor-made polyepichlorohydrin-based anion exchange membrane (AEM) surface was modified using an electrophoretic layer-by-layer (LbL) polyelectrolyte assembly. Negatively charged poly(styrene sulfonate) (PSS) and positively charged poly(ethyleneimine) (PEI) were employed to construct three-layer architectures in which PEI served as the interlayer. The results indicate that the molecular weight of the PEI interlayer strongly influences the surface composition and charge of the final AEMs. RED experiments performed in the presence of Na₂SO₄ revealed that AEMs incorporating the high-molecular-weight PEI exhibited enhanced apparent Cl⁻/SO₄²⁻ selectivity and delivered an increased power density. Fouling tests using a real humic–fulvic acid mixture demonstrated that the hydrophilic PSS top layer effectively mitigated organic fouling and preserved RED performance. Furthermore, short-term stability testing provided a preliminary indication of the stability of the polyelectrolyte layers under short-term operating conditions. This study highlights the critical role of interlayer molecular weight in defining the surface chemistry, apparent ion selectivity, and antifouling behavior of LbL-modified tailor-made AEMs, providing important design guidelines for improving RED performance in realistic feedwaters. Full article

Nanofiltration membranes have emerged as a crucial class of pressure-driven separation materials, positioned between ultrafiltration and reverse osmosis in terms of selectivity, permeance, operating pressure, and energy consumption. Their ability to remove fine contaminants—including multivalent ions, organic micropollutants, dyes, and macromolecules—has made them essential in water and wastewater treatment, pharmaceutical processing, and various industrial applications. In spite of their growing relevance, the performance of polymeric nanofiltration membranes, such as polyamide, polysulfone, polyethersulfone, polyvinylidene fluoride, and polyimide, is still constrained by weak hydrophilicity and a strong susceptibility to fouling, which collectively decrease permeance, increase operational costs, and shorten membrane lifespan. In recent years, substantial research efforts have focused on designing and engineering the surface chemistry and structural characteristics of nanofiltration membranes to improve water permeance, reduce foulant adhesion, and improve long-term stability. This review provides a comprehensive and comparative assessment of the most recent modification techniques applied to polymer-based nanofiltration membranes. Strategies such as polymer blending, nanoparticle incorporation, physical surface coating, plasma treatment, chemical attachment, layer-by-layer assembly, and interfacial polymerization are critically examined with respect to their effectiveness and practical limitations supported by recent research examples. Special attention is given to how these modification methods affect membrane morphology, hydrophilicity, permeance, and antifouling properties. Eventually, the review highlights emerging ideas and forward-looking design directions that may guide the next generation of nanofiltration membranes toward higher efficiency, improved durability, and broader industrial applicability. Full article

Liquid-like surfaces are constructed by anchoring flexible polymer chains with low glass-transition temperature onto solid substrates, imparting low liquid adhesion and easy sliding. Despite their considerable promise in anti-fouling and anti-adhesion applications, such surfaces have thus far been mainly demonstrated on smooth planar substrates. In this work, we report a waterborne polyurethane superhydrophobic fabric coating that features a liquid-like surface behavior and anti-graffiti functionality. The coating was prepared by incorporating dihydroxy single-end-terminated polydimethylsiloxane (PDMS) into polyurethane backbone, which not only reduces the surface energy of the resulting coating but also allows the formation of PDMS brushes at the coating interface, owing to the orientation and enrichment of PDMS moieties at the surface upon coating formation. The as-prepared coating on cotton and polyester fabrics exhibited static WCAs of 158.4° and 157.3°, with WSAs of 9.1° and 7.9°, respectively. Moreover, the coated fabrics demonstrate excellent anti-graffiti performance and self-cleaning ability. Mechanical durability tests revealed that the coating retained a static WCA of approximately 150° even after 20 laundering cycles or 50 abrasion cycles. Given its waterborne and fluorine-free nature, this strategy offers a feasible pathway to extend liquid-like surfaces from smooth substrates to textile substrates for practical anti-graffiti and self-cleaning applications. Full article

Owing to advantageous properties such as high mechanical strength and wear and hydrolysis resistance, polyvinylidene fluoride (PVDF)-based materials have been widely used to fabricate membranes utilizing in anaerobic membrane bioreactors (AnMBRs) for wastewater treatment. Though AnMBRs can be regarded as high-rate bioreactors, membrane fouling caused by organic, inorganic, and biological contaminants remains an inevitable challenge. In order to alleviate this issue, this review systematically summarizes modification methods including crosslinking, surface coating, and assembly for the loading of functional materials and inorganic nanoparticles onto the membrane surface. Additionally, this review indicates that modified PVDF-based membranes with enhanced conductive or antifouling properties can be effectively applied in AnMBRs, and better chemical oxygen demand (COD) removal efficiency can be achieved compared with those utilizing pristine PVDF membranes. Different from previous reviews, this review proposes technology intensification strategies utilizing pristine PVDF membranes including electrochemical AnMBR (electro-AnMBR) and anaerobic fluidized bed membrane bioreactor (AFMBR). Both of them have demonstrated enormous potential for mitigating membrane fouling relative to conventional AnMBR configurations. Spontaneously, this review underscores the critical need to integrate these intensification strategies with modified PVDF-based membranes as relative studies in this combined area. Therefore, this review provides comprehensive guidance on modification methods of PVDF membranes and technology intensification strategies utilizing modified PVDF-based membranes. Full article

Vanadium dioxide (VO₂)-based thermochromic films are highly attractive for smart window applications due to their ability to dynamically modulate solar radiation in response to ambient temperature. However, their practical deployment is significantly hindered by poor long-term stability in outdoor environments, vulnerability to surface contamination, and insufficient mechanical durability. Herein, we propose a novel strategy to obtain self-cleaning and durable VO₂ composite films, consisting of a VO₂ thermochromic layer covered by either a SiO₂ or TiO₂ overcoat and further modified by a transparent and matter-repellent surface. Multifunctional VO₂ composite films are rationally designed to exhibit superior repellence towards various liquids, thereby imparting excellent anti-fouling property. Crucially, the VO₂ composite film is engineered for high optical transparency to ensure it does not compromise the solar modulation ability of the underlying VO₂ layer. Furthermore, the robust mechanical properties of the SiO₂ or TiO₂ overcoat with matter-repellent modification provide effective protection against abrasion and scratch damages. The resulting VO₂-based composite films demonstrate significantly enhanced environmental stability and operational reliability while maintaining desirable thermochromic performance. This work presents a promising strategy to overcome the stability and durability challenges facing VO₂ smart windows, paving the way for their real-world application in energy-efficient buildings. Full article

Metal corrosion and microbial contamination cause severe damage to marine facilities and result in immeasurable economic losses. Highly efficient and durable anti-corrosion and anti-fouling coatings represent the most effective solution strategy widely employed, whilst two-dimensional graphitic carbon nitride (g-C₃N₄), owing to its non-toxic and highly effective properties, is frequently utilized as a coating filler. Herein, this work innovatively engineered g-C₃N₄ into rod-like structures with layer-oriented alignment through a two-step simplified synthesis process, naturally achieving the self-assembly integration of ultrathin sheets. Subsequently, the special rod-like g-C₃N₄ (RCN) was blended with a polydimethylsiloxane (PDMS) matrix, ultimately yielding a multifunctional nanocomposite coating (RCN/PDMS) that combines mechanical reinforcement, long-term corrosion resistance, and microbial fouling protection. Notably, the compact lamellar structure within uniformly dispersed RCN particles in the polymer matrix effectively enhances the crosslinking density of the composite, significantly improving the coating’s adhesion and tensile strength (1.795 MPa). Furthermore, upon exposure to light, the modified RCN-2 releases substantial reactive oxygen species (ROS), exhibiting pronounced antibacterial activity (90.3% of E. coli and 95.1% of S. aureus) against surface-adhering microorganisms. Following a 60 d marine immersion simulation test, the impedance arc radius of the RCN-2/PDMS coating remained as high as 5.17 × 10⁹ Ω·cm², representing an improvement of nearly two orders of magnitude over pure PDMS coatings. This work expands the application of morphology-controlled g-C₃N₄-based fillers in marine anti-fouling and anticorrosion coatings. Full article

Tapered optical fiber-based surface-enhanced Raman scattering (SERS) probes have emerged as promising miniaturized platforms for chemical and molecular sensing by integrating optical excitation, plasmonic enhancement, and Raman signal collection within a single fiber architecture. Their enhanced light–matter interaction, compact geometry, and remote interrogation capability make them particularly attractive for in situ sensing in confined and complex environments. This review systematically examines recent advances in tapered optical fiber SERS probes, covering enhancement mechanisms, taper fabrication, plasmonic hotspot engineering, and analytical applications. Particular emphasis is placed on how taper geometry and plasmonic nanostructure organization jointly influence sensing performance. Fabrication and hotspot-engineering strategies are critically compared in terms of sensitivity, reproducibility, stability, fabrication complexity, and scalability. Representative applications in biomedical analysis, food safety, and environmental monitoring are further evaluated. Despite these advances, practical implementation remains constrained by insufficient hotspot reproducibility, quantitative reliability in complex matrices, long-term stability and antifouling performance, as well as the limited scalability of current fabrication protocols. Future progress will require balancing analytical sensitivity with reproducibility, robustness, and real-sample compatibility, while advancing deterministic hotspot engineering, selective recognition interfaces, standardized performance evaluation, intelligent spectral analysis, and Lab-on-Fiber integration. Together, these developments could accelerate the transition of tapered optical fiber SERS from laboratory-scale demonstrations to field-deployable platforms for remote and in situ molecular sensing. Full article

Oily wastewater commonly contains dissolved organic contaminants such as dyes, antibiotics, and phenolic compounds. Conventional stepwise treatment processes involve complex operation, high energy consumption, and severe membrane fouling. Multifunctional membranes integrating oil/water separation, pollutant adsorption or catalytic degradation, and membrane self-cleaning provide a promising solution for treating complex oily wastewater. This review summarizes recent advances in multifunctional membranes based on metal oxides, two-dimensional (2D) materials, three-dimensional (3D) porous structures, and biomass-derived materials. Key strategies, including micro and nanoscale structure regulation, wettability control, interlayer channel optimization, heterojunction construction, and active site engineering, are discussed together with the synergistic mechanisms involving oil/water separation, adsorption enrichment, photocatalysis, and Fenton reactions. Approaches for improving membrane flux, separation efficiency, degradation activity, antifouling performance, and cycling stability are also reviewed. Finally, challenges related to scalable fabrication, adaptability to real wastewater, long-term stability, and standardized evaluation are outlined, providing guidance for the design and practical application of multifunctional membranes. Full article

To improve the antifouling and self-cleaning performance of 3003 aluminum alloy, a fluorine-free water-repellent surface was fabricated by combining nanosecond laser texturing with subsequent heat treatment. The effects of scanning speed, laser power, pulse frequency, and scanning interval on surface wettability were systematically investigated. Under the optimal conditions of 2700 mm/s, 6 W, 35 kHz, and 20 μm, the surface achieved a maximum static water contact angle of 154.3 ± 0.8°. Surface characterization showed that laser processing generated hierarchical micro-/nano-scale structures, while heat treatment promoted surface chemical evolution associated with enhanced hydrophobicity. The highly water-repellent behavior resulted from the synergistic effect of hierarchical roughness and heat-treatment-induced surface chemical changes. The fabricated surface exhibited effective self-cleaning performance, achieving a SiO₂ removal efficiency of 98.8% under the specified test conditions. In addition, relatively high water repellency was retained after repeated water-impact and tape-peeling tests. These results demonstrate that nanosecond laser texturing combined with heat treatment provides a simple and environmentally friendly strategy for fabricating water-repellent AA3003 surfaces for antifouling and surface-protection applications. Full article

Hydrophobic and superhydrophobic coatings have attracted considerable attention due to their ability to provide water repellency, self-cleaning, anti-corrosion, anti-icing, and anti-fouling properties, making them promising for a wide range of industrial applications. This review summarizes recent advances in the development of hydrophobic and superhydrophobic coatings, with particular emphasis on wetting mechanisms, material selection, coating formation approaches, durability issues, commercial implementation, and environmental aspects. The analysis examines the principal classes of materials used for coating fabrication, including polymeric materials, inorganic compounds, and composite systems. The mechanisms responsible for the formation of hydrophobic and superhydrophobic surfaces are discussed in terms of surface chemistry modification and hierarchical roughness generation. Attention is devoted to factors limiting long-term performance, such as mechanical wear, chemical degradation, ultraviolet exposure, climatic effects, hydrodynamic erosion, and adhesion-related failures, as well as to current strategies for improving durability. Commercially available technologies and their application areas are reviewed, and the environmental challenges associated with fluorinated compounds are considered. The analysis demonstrates that the combination of controlled surface morphology and reduced surface energy remains an effective approach for achieving durable hydrophobicity, with optimized coating systems reaching contact angles of 160–170° and retaining superhydrophobic properties for more than 500 h under demanding operating conditions. Future developments are expected to focus on environmentally friendly, multifunctional, and long-lasting coating systems. Full article

Environmental concerns regarding the ecotoxicological effects of antifouling biocides have led to the development of products targeting biofilm-forming bacteria. However, the potential for sublethal biocide exposure to promote bacterial adaptation and increase the risk of resistance development poses a potential threat to marine ecosystems and human health, yet it remains insufficiently understood. Although this study focuses on conventional antifouling biocides, the findings are intended to inform the future development and evaluation of both conventional and environmentally friendly antifouling technologies by highlighting the importance of assessing resistance induction at sublethal concentrations. In this study, the effects of three representative antifouling biocides on marine bacterial growth and bacterial adhesion were investigated. Sea-Nine 211 (DCOIT), copper sulphate (CuSO₄), and tributyltin oxide (TBTO; included as a historical reference compound due to its environmental persistence) were tested at four concentrations (0.01, 0.1, 1.0, and 10 µg/mL) against six marine biofilm-forming bacteria: Vibrio proteolyticus, V. aestuarianus, V. harveyi, V. natriegens, Shewanella putrefaciens and Pseudoalteromonas elyakovii. The results showed that Sea-Nine 211 exhibited a strong antibacterial effect at 10 µg/mL against all tested species except V. harveyi, whereas at the lowest concentration it promoted bacterial adhesion in V. proteolyticus. In contrast, TBTO and CuSO₄ showed limited antibacterial activity and increased microbial adhesion at the three lowest concentrations tested. These findings demonstrate that antifouling biocides can induce distinct responses depending on the concentration, ranging from growth inhibition to enhanced bacterial adhesion. Given that reducing biocide release has been proposed as a strategy to mitigate environmental impacts, our results highlight two potential challenges: (i) reduced antifouling efficacy at sublethal concentrations and (ii) an increased risk of bacterial adaptation associated with enhanced adhesion. To support future monitoring and resistance risk assessment, we propose a conceptual Resistance Risk Index (RRI) framework that could contribute to the sustainable management of antifouling agents while accounting for local environmental conditions. Full article

Conventional oral and injectable drug administration still struggles with unstable plasma levels, weak targeting, and considerable systemic toxicity, problems that become especially acute in chronic disease management. Implantable and wearable biomedical devices offer one path around these limits, yet device-only platforms continue to fall short on drug loading, release control, and protection of fragile therapeutics. Integrating nanoparticle-based biomaterials into such devices has therefore moved from a research curiosity to a serious clinical strategy. As a result, understanding the design principles, translational challenges, and clinical potential of these hybrid platforms has become increasingly important. This review provides a comprehensive assessment of four major nanoparticle families—polymeric carriers (PLGA, chitosan, and micelles), lipid-based vehicles (liposomes, SLNs, and NLCs), inorganic systems (gold, mesoporous silica, iron oxide, and calcium phosphate), and hybrid composites—focusing on how their physicochemical properties govern drug encapsulation, release behavior, and tissue compatibility. These classes are then linked to specific implantable formats such as drug-eluting stents, nano-enabled scaffolds, and reservoir depots, and to wearable formats including transdermal patches, microneedle arrays, biosensor-coupled patches, and patient-actuated devices. A dedicated section addresses stimuli-responsive release driven by pH, enzymes, temperature, and electrical or magnetic fields, alongside closed-loop platforms that pair real-time biosensing with on-demand dosing. Surface engineering strategies, ligand targeting, antifouling coatings, antimicrobial layers, and immune-modulating chemistries are also discussed, together with the central translational hurdles: long-term stability, foreign body response, scale-up, sterilization, and regulatory classification of combination products. Finally, the review outlines near-term directions, including AI-driven dosing, 4D bioprinting, biomimetic nanocarriers, gene therapy delivery, and bioresorbable electronics, that together suggest where these hybrid platforms are likely to mature next. Full article

Photocatalytic antibacterial coatings have emerged as a promising antibiotic-free strategy for combating healthcare-associated infections, biofilm formation, marine biofouling, and environmental microbial contamination. Unlike conventional antimicrobial approaches, photocatalytic systems continuously generate reactive oxygen species (ROS) under light irradiation, enabling broad-spectrum antimicrobial activity while minimizing the risk of antimicrobial resistance. This review systematically summarizes the fundamental mechanisms underlying photocatalytic antibacterial activity, including photogenerated charge-carrier dynamics, ROS generation pathways, and microbial inactivation processes. We further highlight recent advances in photocatalyst design, spanning conventional semiconductor photocatalysts, heterojunction engineering, cocatalyst modification, and two-dimensional material-assisted strategies for enhanced photocatalytic performance. Crucially, particular emphasis is placed on coating architectures and interfacial regulation, including encompassing fabrication methodologies, coating–substrate adhesion, internal heterointerface design, and coating–microorganism interactions, which dictate long-term durability and antibacterial efficacy. Finally, we explore the diverse applications of these coatings in medical devices, environmental remediation, and marine antifouling, while identifying current bottlenecks and future research trajectories toward developing durable, highly efficient, and clinically translatable antimicrobial surface technologies. Full article

Hollow fiber loose nanofiltration (HF-LNF) has attracted increasing attention as a pressure-driven membrane platform that combines loose nanofiltration (LNF) selectivity with the high packing density and self-supporting geometry of hollow fibers. This review critically evaluates recent advances in HF-LNF membranes, including controllable fabrication strategies, surface functionalization techniques, and practical engineering applications, with a discussion of life cycle assessment (LCA) for evaluating the environmental and economic sustainability of HF membrane systems. Phase inversion, interfacial polymerization (IP), coating, and grafting are compared in terms of structural controllability, process complexity, selective-layer stability, modification uniformity, reproducibility, and scale-up feasibility. Phase inversion is relatively compatible with continuous hollow-fiber spinning, but independent regulation of the support and selective layer remains difficult. IP provides greater control over selective-layer chemistry and effective pore size, whereas coating and grafting offer flexible surface functionalization but may be limited by additional transport resistance, layer durability, and non-uniform modification of curved surfaces. Direct HF-LNF application remains concentrated on dye/salt separation. Based on the evidence from HF-NF or flat LNF systems, the potential of HF-LNF in water softening, heavy metal removal and emerging pollutant control is analyzed. Critical challenges restricting industrial translation are discussed, including poor long-term antifouling capacity and difficulties in large-scale, low-cost manufacturing. On this basis, LCA is further introduced as a decision-support framework for identifying potential environmental hotspots in membrane manufacturing and operation, while the limited availability and comparability of HF-LNF-specific life-cycle data are explicitly recognized. Ultimately, it is proposed to focus on novel functional materials, eco-friendly preparation processes, and scaled membrane engineering, aiming to offer theoretical support for the rational design and real-world industrial deployment of next-generation HF-LNF membranes. Full article