Search Results (136)

Direct air capture (DAC) requires carbon capture interfaces that operate under highly dilute CO₂ conditions while minimizing thermal and chemical regeneration penalties. Carbonic anhydrase (CA) accelerates the reversible hydration of CO₂ to bicarbonate and is therefore a strong biocatalytic candidate for low-temperature CO₂ capture, but its implementation depends on candidate support materials that combine wet-state accessibility, chemical reactivity, mechanical processability and compatibility with membrane architectures. This study reports the preparation and screening of N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride/N-hydroxysuccinimide (EDC/NHS)-reactive biopolymer composite membranes for future carbonic anhydrase (CA) immobilization. Chitosan particles were precipitated with citrate or tripolyphosphate under high-shear homogenization and compared after lyophilization or convective drying. Chitosan-, shellac-, agarose- and cellulose-acetate-based films plasticized with glycerol and/or polyethylene glycol 400 (PEG-400) were then evaluated by optical microscopy, dry-state penetrometric puncture testing, qualitative EDC/NHS-reactivity mapping and Fourier-transform infrared spectroscopy (FTIR). Freshly precipitated chitosan particles showed dendrite-like high-surface morphologies, while lyophilization preserved porous flocculated aggregates and convective drying produced denser collapsed structures. Neat chitosan showed the highest dry-state puncture force (2.230 ± 0.173 N), whereas chitosan/shellac (0.377 ± 0.044 N) and agarose/chitosan/PEG-400 (0.386 ± 0.038 N) provided the strongest reactive-composite compromise between dry-state puncture resistance and EDC/NHS compatibility. The EDC/NHS reactivity map identified chitosan- and shellac-containing films as the chemically most relevant supports because they provide amine and/or carboxyl functionality, whereas agarose and cellulose acetate alone were not directly suitable for zero-length amidation. FTIR spectra confirmed polymer-specific functional signatures and EDC/NHS-associated changes in carbonyl, amide and C-O/C-O-C regions, especially in shellac- and chitosan-containing composites. The results identify chitosan/shellac as the lead candidate membrane and agarose/chitosan/PEG-400 as a hydration-rich comparator for subsequent carbonic anhydrase immobilization studies. This work should be interpreted as a first-stage materials-screening study of candidate membranes for enzyme immobilization. Full article

Pesticide contamination in urban runoff, stormwater, and peri-urban drainage networks is an increasing concern because of the persistence, mobility, and ecological toxicity of many pesticide residues and their transformation products. Nature-based solutions (NBSs), including constructed wetlands, bioretention systems, biofilters, and permeable reactive bio-barriers, provide low-energy and ecologically compatible platforms for urban water treatment; however, their performance is often constrained by limited sorption capacity, substrate saturation, variable hydraulic loading, and incomplete degradation of persistent pesticides. Biochar offers a multifunctional amendment for strengthening these systems because its tunable porosity, surface functionality, mineral composition, redox activity, and microbial habitat-forming capacity can support pesticide adsorption, catalytic transformation, and biodegradation. This review critically evaluates biochar-integrated NBSs for pesticide-contaminated urban water systems by linking biochar production and modification strategies with pesticide removal mechanisms, biochar–microbe interactions, engineered treatment configurations, and field-scale applicability. A comparative synthesis is provided across material-level mechanisms, system-level performance, machine learning-assisted prediction, techno-economic feasibility, life-cycle impacts, and environmental risk considerations. By integrating material properties, removal mechanisms, NBS configurations, predictive modeling, sustainability assessment, and risk considerations, this review provides a broader comparative basis than previous studies focused mainly on individual aspects of biochar-based pesticide remediation. Future priorities include standardized biochar production, long-term field validation, spent-biochar management, ecotoxicological assessment, and data-driven optimization of biochar-assisted NBSs. Full article

Biocatalysis has emerged as a mainstay in the field of sustainable chemical synthesis owing to its high selectivity, mild reaction conditions, and reduced environmental impact. Traditional enzyme engineering approaches, such as rational design and directed evolution, are often associated with limited throughput and a limited understanding of sequence–structure–function relationships, despite high experimental costs. In recent years, the integration of machine learning (ML) into enzyme engineering has emerged as a transformative approach, enabling data-driven prediction, design, and optimization of biocatalysts, thereby enhancing performance and applications. This review provides a comprehensive overview of ML-guided strategies to improve key enzymatic parameters, including the turnover number (k_cat), substrate affinity (K_m), and catalytic efficiency (k_cat/K_m), with a focus on mechanistic insights and performance outcomes. The integration of ML models into design–build–test–learn (DBTL) cycles accelerated directed evolution, reduced screening efforts, and enabled targeted mutagenesis. Beyond applications, this review also discusses the current limitations of ML-guided approaches, including data scarcity, model interpretability, and challenges in predicting complex mutations and allosteric effects. The gap between computational predictions and experimental outcomes is identified, and the role of ML integration with enzyme kinetics, molecular dynamics, and high-throughput experimentation is emphasized. Future directions, such as generative AI, explainable ML, and autonomous laboratories, are discussed for next-generation biocatalytic applications. Full article

In recent years, synergistic effects between inorganic clay minerals (e.g., montmorillonite, sepiolite, kaolinite) and bio-based flame retardants (e.g., chitosan-based, lignin-based, phytate-based) have achieved certain progress in the area of polymer flame retardancy. The effects of bio-based flame retardants are exerted through mechanisms such as catalytic char generation and vapour-phase hindrance. However, they have limitations when used alone, including insufficient thermal stability and the need for a high dosage. Inorganic clays form physical barriers through their layered or tubular structures. The high thermal stability of these structures suppresses heat and mass transfer, thereby offsetting the shortcomings of bio-based flame retardants. This synergistic combination greatly improves the flame retardancy of polymer composites, often strengthening their mechanical performance in the process. It therefore offers great potential for the design of multifunctional, eco-friendly flame-retardant polymer composites. Nevertheless, a systematic review of the synergistic mechanisms, fabrication approaches and application progress of different inorganic clay minerals when combined with various bio-based flame retardants is still lacking. Therefore, this article offers a comprehensive review of the current developments of synergistic systems that incorporate various primary clays, such as sepiolite and montmorillonite, with bio-based flame retardants for usage in polymers. Before this, the synergistic flame-retardant mechanism and the key preparation techniques of the composite system were explained in detail. Finally, this article puts forward solutions to the current challenges and sets out prospects for innovation in the designing of flame-retardant materials and the optimisation of processes. The aim is to promote the sustainable growth of efficient, eco-friendly flame-retardant materials. Full article

Aerogels represent an extraordinary class of materials characterized by remarkable properties, including an exceptionally high porosity (approximately 99.8%), minimal weight, extraordinarily low density, low thermal conductivity, a diminished dielectric constant, and a reduced refractive index. These attributes arise from their extensive micro-meter-sized pores. In recent years, there has been a notable surge of interest in carbon or carbon nanotube (CNT) based aerogels due to their compelling potential across various applications, encompassing sensors, energy systems, and catalysis, among others. In the context of our ongoing investigation, we have successfully synthesized lightweight aerogels by incorporating copper and carbon nanotubes (Cu-CNT) through electrospinning. Intriguingly, these aerogels exhibit an electrical conductivity of approximately 0.5 × 103 S/cm, positioning them within the realm of semiconductors. Concurrently, their density measures approximately 1.669 g/c.c (similar to CNTs), underscoring their notably low mass. These semi-conductive aerogels, uniquely characterized by their lightweight nature and expansive surface area (approximately 442 m²/g), manifest considerable potential across a spectrum of applications. This includes catalytic processes, energy storage mechanisms, bio-sensing technologies, thermoelectric systems, and the burgeoning domains of micro and wearable electronics. The distinctive combination of properties within these aerogels augments their suitability for these diverse applications, offering the prospect of innovative and impactful advancements in various scientific and technological arenas. Full article

Plastic manufacturing depends heavily on petroleum-derived monomers like terephthalic acid, the main component of polyethylene terephthalate (PET). However, the depletion of fossil resources and increasing environmental concerns have heightened the need for sustainable alternatives. Lignocellulosic biomass has emerged as a promising resource due to its renewable, abundant, and eco-friendly nature. Understanding its chemical composition enables conversion of this biomass into platform chemicals, such as 2,5-furandicarboxylic acid (FDCA) and lactic acid, derived from cellulose and hemicellulose. These can be polymerized into bio-based plastics such as polyethylene furanoate (PEF), polylactic acid (PLA), and polyhydroxyalkanoates (PHAs), offering greener alternatives to fossil-based plastics. PEF features rigid furan rings that enhance thermal stability, mechanical strength, and barrier properties, and reduce gas permeability compared to PET. PLA is a renewable, biodegradable plastic widely used in packaging and medical applications. This review covers the chemical composition of lignocellulosic biomass cellulose, hemicellulose, and lignin, and various pretreatment strategies, chemical, physicochemical, and physical, to overcome biomass recalcitrance and improve conversion efficiency. It also highlights recent catalytic advances in transforming cellulosic carbohydrates into bio-based plastic precursors such as FDCA and lactic acid. Lastly, this review discusses polymerization pathways for producing PEF and PLA, emphasizing their role in reducing the environmental impact of polymer manufacturing and promoting green chemistry principles. Full article

Nano–bio hybrid catalysts have emerged as a promising platform for sustainable energy conversion by integrating the high selectivity of enzymes with the structural robustness and conductivity of nanomaterials. In recent years, the growing demand for clean energy technologies has driven the development of biohybrid systems capable of efficient electron transfer, enhanced catalytic activity, and improved operational stability. This review comprehensively discusses the design principles, mechanistic foundations, and performance metrics of enzyme–nanomaterial interfaces for energy-related applications. We first outline the fundamentals of enzymatic redox catalysis and the limitations of free enzymes in practical systems. Subsequently, we examine the functional roles of nanomaterials including carbon-based materials, metal and metal oxide nanoparticles, and two-dimensional platforms such as MXenes in facilitating enzyme immobilization and promoting direct or mediated electron transfer. Special emphasis is placed on engineering strategies at the bio–nano interface, including immobilization techniques, surface functionalization, and structural tuning to optimize catalytic efficiency. The review further highlights representative hybrid systems based on laccase, glucose oxidase, peroxidase, and hydrogenase enzymes, and evaluates their applications in biofuel cells, solar–bio hybrid systems, green oxidation reactions, and self-powered biosystems. Stability challenges, deactivation mechanisms, and enhancement strategies such as polymer coatings, cross-linking, and nanoconfinement are critically analyzed. Finally, emerging directions including artificial enzymes, AI-guided catalyst design, and self-healing bioelectrodes are discussed to provide a forward-looking perspective on next-generation sustainable bioelectrocatalytic systems. Full article

Antimicrobial resistance represents one of the most formidable global health crises of the 21st century, driven by the diminishing efficacy of conventional antibiotics due to bacterial adaptation and biofilm formation. In response, antimicrobial nanoformulations have emerged as a transformative therapeutic paradigm, offering multifaceted and innovative mechanisms to combat resistant pathogens. This comprehensive review delineates the broad scope and distinct novelty of nano-enabled antimicrobial strategies, moving beyond the single-target limitations of traditional drugs. We systematically explore the diverse architectural classes of nanoformulations—including metallic, polymeric, and self-assembling nanostructures—and elucidate their unique mechanistic actions. These encompass (1) physical disruption of microbial membranes via electrostatic interactions; (2) catalytic generation of reactive oxygen and nitrogen species to induce an ‘oxidative storm’; (3) intracellular sabotage of essential metabolic pathways; (4) the ‘Trojan horse’ strategy for enhanced drug delivery and bioavailability; (5) efflux pump bypass to counteract a major resistance mechanism; (6) penetration and eradication of resilient biofilms; and (7) disarming pathogens through quorum sensing and virulence inhibition. Furthermore, this review highlights the immunomodulatory potential of nanoformulations; their activity beyond bacteria against fungi, viruses, and parasites; and the critical role of the nano-bio interface defined by surface physicochemistry. We also address the translational pathway, considering challenges in nanotoxicology, scalability, and regulatory approval, alongside the ecological impact and economic horizon of these technologies. This sector is projected to reach USD 5.4 to 8.96 billion by 2033 to 2034, with compound annual growth rates of 11 to 21% across antimicrobial nanomaterials, nanocoatings, and nanomedicine applications. By integrating insights from computational modeling and in silico design, this review underscores how nanoformulations leverage synergistic, multi-target approaches to overcome resistance, enhance therapeutic efficacy, and represent a significant leap forward in the future of infectious disease management. The novelty lies in the holistic and mechanistic synthesis of how nanotechnology is redefining antimicrobial warfare, offering a promising arsenal to avert a post-antibiotic era. Full article

Development of green and efficient technologies for valorizing crayfish shell waste is crucial for enhancing industrial value. This study presents an integrated strategy for the extraction and structural engineering of chitin using a novel alkaline deep eutectic solvent (DES) system composed of lysine and monoethanolamine (LysMEA), which enables the simultaneous deproteinization and architectural modification of chitin. Following mild demineralization, the optimized process yielded chitin with 97.1% purity and a high molecular weight of 209.3 kDa. DES demonstrated considerable reusability and decolorization capability. Structural characterization revealed that the LysMEA system effectively engineered the chitin architecture, resulting in lower crystallinity and a larger surface area compared to conventional methods. This engineered structure rendered the chitin highly accessible to enzymes. Consequently, the chitin extracted by LysMEA exhibited superior reactivity, achieving a deacetylation degree of 63.7% when catalyzed by Bacillus aryabhattai chitin deacetylase, significantly outperforming chitin obtained via acid-alkali or acidic DES methods. Molecular dynamics simulations elucidated the mechanism, showing that lysine and monoethanolamine molecules penetrated the chitin fiber bundles at high temperatures, weakening interchain hydrogen bonds and partially separating the chains. This work provides a green route for producing enzymatically reactive chitin, demonstrating the potential of solvent-based structural engineering in biocatalytic valorization. Full article

Smart healthcare is rapidly emerging as a transformative paradigm, enabling simultaneous health monitoring, therapeutic intervention, and early prediction of disease onset. In this context, electrochemical monitoring systems have attracted growing interest due to their cost-effectiveness, ease of operation, miniaturization and compatibility with wearable platforms. Accordingly, conductive hydrogel-based electrochemical (bio)sensors have gained significant attention for health monitoring owing to their soft mechanical properties, high water content, excellent biocompatibility, and ability to form intimate, conformal interfaces with biological tissues. Their three-dimensional polymeric networks facilitate efficient ion transport and mechanical flexibility, making them particularly suitable for wearable and noninvasive sensing and monitoring applications. However, the intrinsically limited conductivity and catalytic activity of pristine hydrogels often constrain their electrochemical performance. To overcome these limitations, functional nanomaterials such as metal–organic frameworks (MOFs) and MXene (MX) nanosheets have been increasingly integrated into hydrogel matrices to enhance conductivity and electrochemical activity. This review provides a comprehensive and critical comparison of recent advances in MOF- and MX-integrated conductive hydrogels for electrochemical health monitoring. In addition to material design strategies and sensing performance, emerging trends in data-driven sensing aimed at improving signal interpretation and multi-analyte discrimination are systematically discussed. Key challenges related to long-term stability, biocompatibility, scalability, and intelligent system integration are critically assessed, and the future potential of these platforms within closed-loop architectures is highlighted, paving the way for next-generation conductive hydrogel-based electrochemical sensors in smart healthcare applications. Full article

The increasing energy demand and global dependence on conventional fuels have resulted in severe greenhouse gas (GHG) emissions, necessitating the development of sustainable bioenergy alternatives. Algal is recognized as a promising feedstock for the production of fourth-generation biofuels. This study optimizes catalytic pyrolysis of Arthrospira platensis for bio-oil production via a dual-bed catalyst system of iron-impregnated dolomite (Fe/DM) and a copper-impregnated spent fluid catalytic cracking catalyst (Cu/sFCC). A face-central composite design (FCCD) and response surface methodology (RSM) were used for the delineation of optimal conditions, ensuring that all experimental tests remained within feasible operating conditions of 500–600 °C, a reaction time of 45–75 min, a N₂ flow rate of 50–200 mL/min, and a catalyst loading of 5–20 wt%. The bio-oil yield was maximized at 39.73 ± 2.86 wt% at 500 °C for 45 min, a N₂ flow of 50 mL/min, and 5 wt% catalyst loading to feedstock with a 0.4:0.6 mass ratio of Fe/DM: Cu/sFCC. The dual-catalysts combined Brønsted and Lewis acid sites enhanced the catalytic activity, which promotes the cleavage of carbon–carbon and carbon–hydrogen bonds, including the mechanism of catalytic pathways such as dehydration, decarboxylation, oligomerization, aromatization, and further cracking reactions, and was successful in converting high-molecular-weight molecules into lighter hydrocarbons and significantly improving product selectivity, demonstrating a highly effective pathway for producing high-quality sustainable biofuel. Full article

For those who did not follow the invention and development of enantioselective catalysis, this review introduces pertinent historical aspects of the field and presents the scientific concepts of asymmetric bio- and organocatalysis. They are powerful technologies applied in organic laboratories and industry. They realize chiral amplification by converting inexpensive achiral substrates and reagents into enantiomerically enriched products using readily recoverable solvents, if any are used. Racemic substrates can also be deracemized catalytically. More sustainable fabrications are now available that require neither toxic metallic species nor costly reaction conditions in terms of energy, atmosphere control, product purification, and safety. Nature has been the source of the first asymmetric catalysts (microorganisms, enzymes, alkaloids, amino acids, peptides, terpenoids, sugars, and their derivatives). They act as temporary chiral auxiliaries and lower the activation free energy of the reaction by altering the reaction mechanism. Reductions, oxidations, carbon-carbon and carbon-heteroatom bond-forming reactions are part of the process panoply. Asymmetric catalyzed multicomponent and domino reactions are becoming common. Typical modes of activation are proton transfers, hydrogen bonded complex formation, charged or uncharged acid/base pairing (e.g., σ-hole catalysts), formation of equilibria between achiral aldehydes and ketones with their chiral iminium salt or/and enamine intermediates, umpolung of aldehydes and ketones by reaction with N-heterocyclic carbenes (NHCs), phase transfer catalysis (PTC), etc. Often, the best enantioselectivities are observed with polyfunctional catalysts derived from natural compounds, but not always. They may combine to form chiral structures containing nitrogen, phosphorus, sulfur, selenium, and iodine functional moieties. Today, man-made enantiomerically enriched catalysts, if not enantiomerically pure, are available in both enantiomeric forms. Being robust, they are recovered and reused readily. Full article

Metallogels constitute a rapidly expanding class of hybrid soft materials in which metal ions, metal complexes, or metal-containing nanoparticles play a decisive structural and functional role within a three-dimensional gel network. Their unique combination of supramolecular assembly, metal-ligand coordination, and dynamic network behaviour provides tunable mechanical, optical, electrical, redox, and catalytic properties that are not accessible in conventional hydrogels or organogels. This review systematically summarises current knowledge on metallogels, beginning with a classification based on matrix type, dominant metal interaction and functional output, spanning metallohydrogels, metal-organic gels, metal-phenolic gels, nanoparticle-based gels, polymer-based metallogels and low-molecular-weight metallogels. Key synthesis pathways are discussed, including coordination-chemistry-driven formation, metal-ligand self-assembly, in situ reduction, diffusion-mediated strategies, sol-gel-like polymerisation, enzyme-assisted routes, and bio-derived fabrication. Particular emphasis is placed on structure-function relationships that enable the development of catalytic, conductive, luminescent, antimicrobial, and biomedical metallogels. The examples compiled here highlight the versatility and transformative potential of metallogels in next-generation soft technologies, including sensing, energy conversion, wound healing, drug delivery, and emerging applications such as soft electronics and on-skin catalytic or bioactive patches. By mapping current progress and emerging design principles, this review aims to support the rational engineering of metallogels for advanced technological and biomedical applications Full article

Integrating catalytic function with oxygen-carrying capability into bi-functional materials represents a promising strategy for reverse chemical looping pyrolysis (RCLPy), which utilizes a reduced metal oxide to improve the bio-oil quality through in situ hydrogen donation and deoxygenation. In this study, a systematic evaluation of two typical catalysts (CaO and ZSM-5) was conducted for the pyrolysis of microalgae Nannochloropsis sp. under RCLPy conditions. First, the effect of each catalyst on the pyrolysis behavior of microalgae was analyzed by Gaussian fitting of derivative thermogravimetric (DTG) curves. Second, gases evolved during thermogravimetric analysis (TGA) were monitored in real time using Fourier-transform infrared spectroscopy (FTIR) for detecting CO, CO₂, H₂O, and functional groups (e.g., C–C, C=C, C=O), and mass spectrometry (MS) for tracking nitrogen-containing compounds. Third, the composition of bio-oils produced under RCLPy conditions was examined by Gas Chromatography–Mass Spectrometer (GC–MS) analysis. The results demonstrate that the catalyst enhances the bio-oil quality by elevating the content of aromatics up to 41.9 area% and that of aliphatic hydrocarbons to 19.1 area%, respectively, while reducing the content of nitrogen-containing compounds to 3.8 area%. However, the elimination pathway of oxygen and nitrogen elements involves different mechanisms. These findings provide valuable guidance for the design of bifunctional oxygen carriers aimed at enhancing the quality of bio-oil derived from microalgae pyrolysis. Full article

Enzyme technology, characterized by high efficiency, environmental compatibility, and precise controllability, has become a pivotal biocatalytic approach for quality enhancement and nutritional improvement in modern food industries. This review summarizes recent advances and underlying mechanisms of enzyme applications in food processing optimization, nutritional enhancement, and functional food development. In terms of process optimization, enzymes such as transglutaminase, laccase, and peroxidase enhance protein crosslinking, thereby markedly improving the texture and stability of dairy products, meat products, and plant-based protein systems. Proteases and lipases play essential roles in flavor development, maturation, and modulation of sensory attributes. From a nutritional perspective, enzymatic hydrolysis significantly improves the bioavailability of proteins, minerals, and dietary fibers, while simultaneously degrading antinutritional factors and harmful compounds, including phytic acid, tannins, food allergens, and acrylamide, thus contributing to improved food safety and nutritional balance. With respect to functional innovation, enzyme-directed production of bioactive peptides has demonstrated notable antihypertensive, antioxidant, and immunomodulatory activities. In addition, enzymatic synthesis of functional oligosaccharides and rare sugars, glycosylation-based modification of polyphenols, and enzyme-assisted extraction of plant bioactive compounds provide novel strategies and technological support for the development of functional foods. Owing to their high specificity and eco-friendly nature, enzyme technologies are driving food and nutrition sciences toward more precise, personalized, and sustainable development pathways. Despite these advances, critical research gaps remain, particularly in the limited mechanistic understanding of enzyme behavior in complex food matrices, the insufficient integration of multi-omics data with enzymatic process design, and the challenges associated with translating laboratory-scale enzymatic strategies into robust, data-driven, and scalable industrial applications. Full article