Search Results (844)

The increasing global demand for natural bioactive compounds in the food, nutraceutical, and pharmaceutical sectors highlights the need for sustainable extraction technologies capable not only of efficiently valorizing crop biomass and agro-waste but also of producing reproducible and standardized botanical extracts. Subcritical water extraction (SWE), which utilizes pressurized hot water at temperatures between 100 °C and 374 °C to modify solvent properties, has emerged as a promising green alternative to conventional organic solvent-based extraction methods. Despite its advantages in terms of environmental compatibility, extraction efficiency and tunable selectivity, the industrial application of SWE remains limited, and strategies for obtaining standardized extracts using this technology are still insufficiently explored. This review provides a comprehensive overview of SWE in the context of natural product extraction and the development of standardized plant extracts. The fundamental principles of SWE are discussed, including temperature-dependent changes in water polarity, solvent–solute interactions, and the influence of key process parameters such as temperature, pressure, extraction time, and particle size. Particular emphasis is placed on how these factors affect extraction selectivity, phytochemical composition, and reproducibility, which are critical aspects for extract standardization. Mechanistic insights into plant cell disruption, compound stability, and hydrothermal transformations under SWE conditions are also examined. Recent applications of SWE for the extraction of phenolics, flavonoids, terpenoids, alkaloids, and other pharmacologically relevant compounds are reviewed, highlighting the relationship between extraction conditions and extract quality. Finally, current challenges and future perspectives for integrating SWE into the production of standardized botanical extracts suitable for food, nutraceutical, and pharmaceutical applications are discussed, paving the way for the wider industrial adoption of this environmentally friendly technology. Full article

To promote green chemistry and improve the utilization of plant resources, flavonoids from Dalbergia pinnata (Lour.) Prain were extracted in this study by combining NADES (natural deep eutectic solvents) with UAE (ultrasound-assisted extraction). Among the 13 synthesized NADES, choline chloride (ChCl)–urea (NADES-13) exhibited the highest extraction rate, outperforming traditional organic solvents. The optimal conditions determined by response surface methodology (RSM) were as follows: ChCl–urea molar ratio of 1:3, moisture content of 60%, liquid-to-material ratio of 28.5 mL/g, ultrasonic extraction time of 49 min, and temperature of 62 °C. Under these conditions, the extraction rate reached 117.95 ± 5.97 mg/g, a 73.5% improvement compared with 80% EtOH extraction. The comparison of the two algorithms showed that RSM (R = 0.9981, RMSE = 0.6570) had better fitting accuracy and prediction stability under small sample conditions than MLP (R = 0.9427, RMSE = 5.261) and RF (R = 0.9431, RMSE = 5.2442). DFT (density functional theory) analysis demonstrated that hydrogen bonds, Van der Waals forces, and cation–π interactions mediate the interaction between NADES-13 and flavonoids. Ultrasonic cavitation-induced cell wall damage and the hydrogen-bond network of NADES-13 were confirmed separately by SEM (scanning electron microscopy) and FTIR (Fourier transform infrared spectroscopy). In vitro experiments showed that the extract possessed concentration-dependent antioxidant activity and strong antibacterial activity, with an inhibition rate of 96.87 ± 5.09% against Escherichia coli at a concentration of 0.04 mg/mL. In this study, a “Smart Optimization–Molecular Mechanism–Activity Verification” green extraction system was developed, which offers an efficient and environmentally friendly strategy for extracting plant bioactive components and contributes to the progress of green chemistry. Full article

The application of lignin-based films is often restricted by traditional processing methods that rely on toxic organic solvents and harsh chemical reagents, which result in poor compatibility with the polymer matrix and difficulty balancing transparency, barrier, and toughness. Here, lignin was green-modified by ternary deep eutectic solvent (choline chloride-lactic acid-ethanol), and ZnO hybrids with cellulose nanocrystals (CNC) as anchor points were introduced to realize the stability and uniform dispersion of ZnO in the polyvinyl alcohol (PVA) matrix. The prepared composite film maintains a transmittance of about 78% at 800 nm while achieving a wide spectrum of ultraviolet shielding. The barrier properties of the film were markedly improved: the water vapor permeability (WVP) decreased to 0.24 × 10⁻⁷ g·m⁻¹·h⁻¹·Pa⁻¹, and the oxygen permeability (OTR) to 6.98 cm³·m⁻²·24 h⁻¹·0.1 MPa⁻¹. In addition, the mechanical flexibility and durability of the material were significantly improved, as evidenced by a tensile strain of 109%. In the insurance experiment, compared with the blank film, the browning degree and weight loss of the composite film were relatively low. The scalable and low-solvent consumption route provides a practical idea for the application of lignin in food preservation. Full article

Biomass represents a vital and sustainable resource for developing renewable materials with the potential to replace petroleum-based chemicals. Paulownia wood has high cellulose content and a loose wood structure, giving it natural advantages as a biomass material. Therefore, in this study, Paulownia wood was selected as a lignocellulosic feedstock. An integrated pretreatment process combining a deep eutectic solvent (DES) with an organic solvent was employed to efficiently remove lignin and hemicellulose, yielding cellulose-enriched residues. Subsequently, high-intensity ultrasonication was applied to convert the residues into cellulose nanofibers and nanocrystals. Using the extracted cellulose and nanocellulose, a dual-crosslinked network composite hydrogel was fabricated. The structural, mechanical, thermal, swelling, and conductive properties of the hydrogel were systematically investigated. The results show that, compared with the blank group hydrogel, the addition of nanocellulose increased the maximum tensile strength and tensile strain of the composite hydrogel by approximately 113% and 81%, respectively; meanwhile, the compressive strengths of the nanocellulose-based hydrogels (0.04575–0.09060 MPa) are higher than that of the blank group hydrogel (0.04235 MPa), confirming that the incorporation of nanocellulose significantly enhances the mechanical strength and elasticity of the hydrogel. The introduction of an AlCl₃/ZnCl₂ solvent system imparts appreciable electrical conductivity. Furthermore, the composite hydrogel maintains structural integrity after full swelling, indicating good dimensional stability and reusability. This work not only presents a green and efficient strategy for valorizing Paulownia biomass but also offers a novel design route for high-performance conductive hydrogel materials, highlighting their potential application in areas such as flexible electronics and energy storage. Full article

Organic solvent reverse osmosis (OSRO) is an emerging membrane technology for low-energy separation of organic mixtures, yet developing OSRO membranes with both high permeance and robust stability remains challenging. Herein, we present a surface modification strategy using a D-glucamine/ethanol solution to tailor the physicochemical properties of a crosslinked polyimide-supported polyamide OSRO membrane. D-glucamine, as an amino sugar alcohol compound contains a primary amino group and multiple hydroxyl groups, endowing it with specific chemical reactivity and potential for interface modification. The optimized OSRO membrane exhibited a significantly decreased water contact angle from 52.6° of the control membrane to 36.6°, indicating substantially enhanced surface hydrophilicity. The optimized membrane (TFC-D-0.2) achieves a high water permeance of 12.84 LMH/MPa with a NaCl rejection of 98.25% and demonstrates excellent operational stability and pressure resistance (2.5~4.0 MPa). The membrane also shows good tolerance to most organic solvents, maintaining >96.5% NaCl rejection after 30 days of immersion in all tested solvents except acetone. In concentrating ethyl cinnamate/ethanol mixtures over 50 h, the membrane delivers stable performance with an ethanol permeance of ~2.5 L m⁻² h⁻¹ MPa⁻¹ and a solute rejection of >88%. This work provides an effective surface modification strategy for developing high-performance OSRO membranes, holding promise for green separation processes in fine chemical industries. Full article

Developing membranes with superior antifouling properties is crucial for efficient and sustainable water treatment. In this study, polysulfone (PSM) composite membranes were fabricated by incorporating hydroxylated titanium nanotubes (TNT@OH) via the non-solvent-induced phase separation method. The hydroxylation of TNTs enhanced their dispersion in the polymer matrix and promoted strong polymer–nanoparticle interactions. Comprehensive characterization using FTIR, XRD, TGA, FESEM, and AFM confirmed the successful integration of TNT@OH, resulting in membranes with improved hydrophilicity, porosity, and thermal stability. The contact angle decreased from ~88° for neat PSM to ~50° at 7 wt% TNT@OH, while surface free energy increased significantly. Mechanical strength and flexibility were also enhanced at optimal TNT@OH loadings (3–5 wt%), owing to uniform dispersion and strong interfacial bonding. Filtration experiments using humic acid (HA) and natural organic matter (NOM) demonstrated remarkable improvements in water flux, rejection efficiency, and fouling resistance. The composite membranes achieved HA rejection rates of up to 98%, with reduced irreversible fouling and higher flux recovery ratios across multiple filtration–cleaning cycles. The proposed antifouling mechanism is attributed to the formation of a stable hydration layer by surface hydroxyl groups, which prevents foulant adhesion and facilitates cleaning. These findings suggest that incorporating TNT@OH into polysulfone membranes is a promising approach for developing high-performance ultrafiltration membranes with enhanced permeability, mechanical robustness, and long-term antifouling stability, thereby making them suitable for advanced water purification applications. Full article

In this study, a microcrystalline cellulose (MCC)-stabilized Pickering emulsion approach was developed to integrate hydrophobic natural deep eutectic solvents (NADES; menthol:decanoic acid, 1:1 molar ratio) into agar-based biopolymer films. MCC was evaluated not only as a filler but also as a functional interfacial component governing hydrophobic phase distribution and structural organization. SEM analysis showed that MCC concentration significantly influenced morphology; films with 0.2% MCC exhibited a more homogeneous structure, whereas 0.5% MCC led to heterogeneous and irregular formations. Mechanically, films with 0.2% MCC showed higher elongation at break (16.37%) compared to 0.5% MCC (9.86%), while tensile strength remained similar (2.75–2.78 MPa). Increased MCC content enhanced surface hydrophobicity, as indicated by higher contact angle values. The 0.5% MCC films exhibited high moisture content (85%) and water solubility (93%), attributed to increased free volume and structural irregularity. Swelling index exceeded 40% in 0.2% MCC films but decreased at higher MCC levels. HS-GC-MS analysis revealed temperature-dependent controlled release of menthol, with significant release at 50 °C compared to 25 °C. Antimicrobial tests demonstrated broad-spectrum activity (8.9–24.2 mm). These results highlight MCC as an effective stabilizer for hydrophobic NADES integration and support the potential of these films for active packaging applications. Full article

Lipid nanoparticles (LNPs) have become the cornerstone of nucleic acid delivery platforms, particularly in RNA-based vaccines and therapeutics. However, the conventional methods of LNP production, which are primarily reliant on microfluidic mixing of aqueous and organic solvent phases, pose limitations in terms of mRNA stability, residual organic contamination, scalability, cost, and environmental impact. These limitations prompted a renewed search for non-conventional strategies with the promise of improving mRNA-LNP encapsulation approaches. These emerging approaches aim to address key bottlenecks, including mRNA hydrolysis-driven degradation, high production losses, and complex downstream purification. Moreover, the ability to decouple LNP synthesis from mRNA encapsulation could enable streamlined, modular manufacturing workflows and customizable payload delivery, including single- or multiple-mRNA payloads, thereby expanding the therapeutic scope of LNPs. This review offers an early insight into the design principles and scalability potential of emerging non-conventional LNP encapsulation approaches, including solvent-free and microfluidics-free methodologies, and pre-built LNP workflows. We also examine trends in emerging LNP encapsulation tools, including high-shear mixing, sonication, membrane contraction, and other approaches. Finally, we extrapolate the suitability of the methods for scale-up approaches and their economic implications based on the process information. Full article

The synthesis of nitrogen-containing heterocycles remains a subject of significant interest due to their applications in medicinal chemistry and materials science. This paper describes the preparation of imidazo[1,2-a]pyridine using a catalytic system consisting of the deep eutectic solvent (DES) choline chloride (ChCl)–tartaric acid (1:2) and I₂ by reaction between 2-aminopyridines and chalcones (1,3-diphenylprop-2-en-1-ones). The proposed mechanism suggests the activation of the chalcone carbonyl by the DES, enhancing the polarization of the conjugated system which suffers electrophilic addition by I₂ to the C=C bond. The resulting intermediate undergoes a nucleophilic attack by 2-aminopyridine followed by cyclization and iodine-promoted oxidation and aromatization to yield the corresponding imidazo[1,2-a]pyridine products. The role of the DES is crucial, as it facilitates carbonyl activation through hydrogen bond interactions, stabilizes reactive intermediates, and promotes protonation–deprotonation steps, thereby eliminating the need for metal catalysts or toxic organic solvents. Theoretical calculations at the PM6 level of theory suggest that the DES acts as a catalyst in this reaction, due to the nature of its components enabling the development of more sustainable synthetic strategies. Full article

The efficient capture of chlorinated volatile organic compounds (Cl-VOCs) represents a significant challenge in environmental protection and sustainable chemical engineering. In this study, a functional deep eutectic solvent (DES) composed of tetrabutylphosphonium bromide ([P₄₄₄₄][Br]) and levulinic acid (LEV) at a 1:2 molar ratio was prepared, and its absorption performance toward two typical Cl-VOCs, namely dichloromethane (DCM) and chloroform (TCM), was evaluated using this DES as a recyclable absorbent. Based on COSMO-SAC model predictions and experimental validation, the [P₄₄₄₄][Br]-LEV (1:2) system was identified as the preferred candidate. Under mild conditions (10 °C, N₂ flow rate of 100 mL/min), the saturated absorption capacities of this DES reached 1521.71 mg/g and 1620.30 mg/g for DCM and TCM, respectively. The absorbent exhibited favorable regeneration stability over five consecutive absorption–desorption cycles, retaining over 90% of its initial absorption efficiency. Mechanistic studies, including proton nuclear magnetic resonance (¹H NMR), Fourier-transform infrared spectroscopy (FT-IR), DSC (Differential Scanning Calorimetry), TGA (Thermogravimetric Analysis) and quantum chemical calculations, including electrostatic potential (ESP), independent gradient model (IGM), and reduced density gradient (RDG), demonstrated that the absorption process was dominated by physical interactions such as hydrogen bonding and van der Waals forces, with no chemical reactions involved. At the laboratory scale, this DES system showed excellent Cl-VOCs absorption performance, providing a useful reference for the rational design of high-efficiency VOC absorbents. Full article

Stable nanoemulsions with fine droplets reduce organic solvent use and improve the dispersion of hydrophobic pesticide. However, current studies on deltamethrin nanoemulsion lack systematic formula optimization, performance evaluation and biosafety assessment. This study developed a stable deltamethrin nanoemulsion (Del@Ne) and tested its physicochemical properties, insecticidal activity and non-target safety. In 2025, the effects of surfactant ratio, dosage, preparation temperature and emulsification method on emulsion stability was systematically investigated. The optimal formula contained an active ingredient (2.5% deltamethrin), a surfactant ratio of 8:1 (#601:#500), a 6% surfactant dosage, a 17.25% oil phase (S-100:DMF = 20:3), and deionised water filled to 100%, prepared by adding deionised water to an oil phase containing deltamethrin and surfactants at 40 °C. Del@Ne exhibited small droplet size and good storage stability (TSI ≈ 1), which had better wettability on peach leaves with contact angle falling from 40.4° to 21.6° in 120 s. Del@Ne also gave higher toxicity against Myzus persicae (LC₅₀ = 66.85 mg L⁻¹) than Del@EC (80.69 mg L⁻¹), while showing lower toxicity to zebrafish, earthworms and Harmonia axyridis, as well as better biocompatibility with human L02 hepatocytes. These results provide references for rapid screening of nanoemulsion formulation parameters and also offer insights for the efficient utilization of hydrophobic pesticides. Full article

Arsenic pollution is a prevalent challenge worldwide due to extensive use dating back thousands of years, and the pentavalent species arsenate (As(V)) is of particular interest because it predominates in oxygenated groundwater. Metal–organic frameworks (MOFs), characterized by their high surface area and tunable surface chemistry, have emerged as promising adsorbents for its rapid and efficient removal. This study systematically evaluated the adsorption performance, physicochemical properties, and regeneration behavior of monometallic Fe-BTC MOF and bimetallic Fe/Cu-BTC for As(V) removal under application-relevant conditions. Fe-BTC exhibited the highest adsorption capacity of As(V) (117.5 mg g⁻¹), whereas Fe/Cu-BTC showed a lower capacity (74.6 mg g⁻¹). Adsorption in tap water decreased slightly for both materials (19–23%), indicating mild competition from coexisting ions. The adsorption behavior followed the Freundlich model, indicating competitive occupation of high-energy sites on Fe-BTC. In contrast, the surface heterogeneity of Fe/Cu-BTC remained unchanged, highlighting its robust characteristics. Adsorption was strongly pH-dependent, reaching a maximum at neutral pH, and regeneration experiments identified ethanol as the most effective desorption agent for Fe-BTC, enabling reuse. Metal-leaching analysis confirmed superior Fe-BTC MOF stability and minimal leaching, whereas Fe/Cu-BTC instability demonstrated risk of secondary Cu contamination. Overall, these findings establish that Fe-BTC and Fe/Cu-BTC MOF are effective for As(V) adsorption, but Fe-BTC outperforms Fe/Cu-BTC as a practical adsorbent. Significantly, Fe-BTC performance is strongly influenced by water matrix composition and regeneration solvent, highlighting considerations for real-world applications. Full article

We report here a thorough study concerning the acylation reaction products of 8-hydroxyquinoline with 2-chloroacyl chloride, with new insights and clarifications in respect to the obtained products brought by NMR and X-ray studies. According to the reaction conditions we employed, three compounds could be obtained: 1-(2-chloro-2-oxoethyl)pyridin-1-ium chloride 10, 8-hydroxyquinoline hydrochloride 11, and the acylated product 8-(2-chloroacetoxy)quinolin-1-ium chloride 12. A certain influence of the catalyst and the used solvent was observed, and feasible explanations for product formations were furnished. The structure of the compounds was proved by using ¹H- and ¹³C-NMR spectra as well as single-crystal X-ray diffraction studies for compounds 12 and 11. According to X-ray crystallography, compounds 11 and 12 have a planar structure and exhibit an ionic crystal structure crystallized as a hydrochloride salt of the corresponding organic base. The crystal structures of both compounds are stabilized by intermolecular hydrogen bonds and π-π stacking interactions. In the crystals of compounds 11 and 12, the structural components are interconnected by a system of intermolecular hydrogen bonding, and a similar one-dimensional array is formed via hydrogen bonding and π-π stacking. The further assembling of the structure for 12 and 11 occurs with the formation of a three-dimensional supramolecular network. Full article

Perylene bisimide derivatives are typical n-type semiconductors as well as redox-active materials. However, it has been difficult to produce thin films by solution processes because of their low solubilities in organic solvents. Perylene bisimide derivatives bearing oligosiloxane moieties exhibit columnar phases over wide temperature ranges, including room temperature and high solubilities in organic solvents. The columnar phases are stabilized by nanosegregation between crystal-like one-dimensional π-stacks and liquid-like mantle consisting of oligosiloxane moieties. The electron mobility at room temperature exceeded 0.1 cm²V⁻¹s⁻¹ in the ordered columnar phases of perylene bisimide derivatives bearing four disiloxane chains. Uniaxially aligned thin films of the perylene bisimide derivatives bearing oligosiloxane moieties could be produced by a spin-coating method. The spin-coated films of the perylene bisimide derivatives bearing cyclotetrasiloxane rings could be insolubilized via in situ ring-opening polymerization by the exposure of the thin films to trifluoromethanesulfonic acid vapors. Uniaxially aligned thin films of perylene bisimide derivatives bearing an ethylene oxide chain as well as cyclotetrasiloxane rings could be doped in an aqueous solution of sodium dithionate, resulting in an anisotropic electrical conductivity. Polymerized thin films of perylene bisimide derivatives bearing a crown ether ring exhibited electrochromism in electrolyte solutions. These compounds formed 1:1 complexes with lithium triflate, exhibiting columnar phases at room temperature. The nanostructures of the complexes were stabilized by the electrostatic interaction between cationic crown-metal units and triflate anions. Full article

Background: Solid pro-nano lipid (SPNL) oral formulations were prepared and tested in rats for enhanced oral bioavailability of cannabidiol (CBD). Methods: The solid formulation at room temperature is a uniform solution of CBD in a mixture of solid lipids and surfactants. Upon contact with aqueous media, it disperses into <200 nm particles. Up to 40% w/w of CBD can be loaded in this formulation into a hard gelatin capsule or mixed with solid additives and compressed into a tablet. Another type of SPNL formulation was prepared from the absorption of a liquid pro-nano lipid formulation onto a solid support, termed LPNL. Results: Pharmacokinetic studies on male Wistar rats (0.295–0.335 kg) reveals that a single oral dose of SPNL or LPNL leads to rapid CBD absorption and high C_max values. The SPNL and LPNL formulations are stable at room temperature for at least 3 months. Powder forms of the SPNL and LPNL were prepared with Neusilin US2, SYLOID 244 FP, microcrystalline cellulose (Avicel PH 102), and mannitol. Both SPNL and LPNL show lesser stability for CBD with mesoporous silica particles such as Neusilin US2 and SYLOID 244 FP. Conclusions: The SPNL formulations do not contain any organic solvent and therefore are safer compared to the SNEDDS systems. These solid lipids-based oral formulations can be applied for the delivery of other lipophilic drugs. Full article