Search Results (5,337)

In this work, three functionalized hybrid composites, CS/PVA-VAN, CS/PVA-VAN@TiO₂ and CS/GO/PVA-VAN@TiO₂, were synthesized and applied for adsorption evaluation on two common non-steroidal anti-inflammatory drugs, i.e., diclofenac (DCF) and ketoprofen (KTP). The structural and morphological characteristics of new composites were identified via Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD) and BET techniques. BET analysis demonstrated that the CS/GO/PVA-Van@TiO₂ composite has a surface area 64.86 m²/g, which is twice that of CS/PVA-Van. Moreover, adsorption evaluation was achieved at an optimum pH condition (pH 5.0) for both drugs. In addition, the kinetic data fitted better in a pseudo-second-order kinetic model, while the adsorption was heterogeneous and multilayer. The adsorption capacity of CS/GO/PVA-VAN@TiO₂ was found to be 114.53 mg/g and 65.20 mg/g for diclofenac and ketoprofen, respectively. Thermodynamic analysis confirmed that the adsorption process was endothermic and spontaneous for all pollutants. Moreover, the kinetic swelling and stability studies demonstrated that graphene oxide contributed to improving the structural compactness and stability of composite. Finally, the adsorption performance of the optimal composite material was investigated in a binary system of non-steroidal anti-inflammatory drugs in various ratios. Full article

Poly(glycidyl methacrylate) (PGMA) is a polymer containing epoxy groups in its side chains, which makes it a suitable platform for the development of functional materials. In this study, crosslinked PGMA-based microspheres were synthesized by suspension polymerization using N,N′-methylenebisacrylamide as a crosslinker, and the effect of incorporating inorganic additives (InAds) (NaCl, CaCO_3, and MgO nanoparticles) during synthesis was evaluated. In all cases, solid microspheres were obtained, exhibiting variations in particle size, sphericity, and aggregation depending on the type and amount of InAds. Thermal stability was characteristic of crosslinked PGMA (i.e., a single broad thermal transition in ~80–110 °C), while water absorption remained within a narrow range (80–120% for t = 40 min). In addition, the number of epoxy groups per gram of sample was 4.83 ± 0.02 mmol g⁻¹. Selected microspheres were subsequently functionalized with polyethyleneimine (PEI) to obtain graft polymers (PGMA–PEI) and evaluated for the adsorption of three model contaminants: Acid Red 27 (AR-27), nitrites, and acetaminophen. PGMA–PEI showed high affinity toward AR-27 and nitrites, achieving high removal efficiencies at acidic and neutral pH, with rapid adsorption kinetics consistent with a pseudo-second-order model, attributed to electrostatic interactions between protonated amine groups and anions. At pH 11, anion desorption was promoted, enabling partial material regeneration. The results highlight the potential of PGMA–PEI microspheres for the removal of AR-27 (maximum retention ~0.25 mg of dye/g of polymer) and nitrites (maximum retention ~0.023 mg of <!-- MathType@Translator@5@5@MathML2 (no namespace).tdl@MathML 2.0 (no namespace)@ --> Full article

Polymer–drug conjugates (PDCs) represent an advanced drug delivery strategy designed to address critical limitations of conventional therapeutics, including poor water solubility, rapid systemic clearance, and off-target toxicity. By covalently linking therapeutic agents to polymeric carriers through rationally designed linkers, PDCs enable improved pharmacokinetic profiles, enhanced stability, and controlled drug release. This review provides a comprehensive overview of the key design principles governing PDC systems, with a particular focus on the role of biofunctional polymers. Essential parameters for polymer selection, including biocompatibility, biodegradability, molecular weight, and functional group availability, are discussed in relation to their influence on drug loading, release kinetics, and biological performance. In addition, both natural and synthetic polymers are evaluated for their ability to improve solubility, modulate biodistribution, and reduce systemic toxicity. An overview of stimuli-responsive PDCs is provided, including pH-, redox-, and temperature-sensitive systems, which enable site-specific and spatiotemporally controlled drug release in response to pathological microenvironments. We emphasize the special role of bioactive polymers such as poly-lysine, hyaluronic acid, chitosan, and gelatin for their intrinsic biological activity, including receptor-mediated targeting, antimicrobial activity, and synergistic therapeutic effects. These properties support the development of dual-active conjugates with enhanced specificity and efficacy. Overall, this review underscores the transition of polymers from passive carriers to active therapeutic components and outlines current challenges and future perspectives for the clinical translation of next-generation PDCs. Full article

To address the limited selectivity of conventional membrane materials toward sulfonamide antibiotics, this study employed a DFT calculation approach to optimize the design of a molecularly imprinted system for sulfadiazine (SDZ). A hierarchical set of template molecules—aniline (ANL), sulfanilamide (SNM), and SDZ—was introduced to systematically elucidate structure-dependent template–monomer matching mechanisms in sulfonamide imprinting systems. Through rational screening, trifluoroethyl methacrylate (TFEMAA) was identified as the optimal functional monomer, with an optimal imprinting molar ratio of 1:4 (SDZ to TFEMAA). Guided by the simulation results, SDZ molecularly imprinted polymers (MIPs) were synthesized via precipitation polymerization and systematically characterized for their morphology and recognition properties. The MIPs exhibited a well-defined spherical morphology with abundant imprinted cavities, achieving adsorption equilibrium within 1.5 h. The adsorption kinetics followed a pseudo-second-order model, indicating a chemisorption-dominated process. Scatchard analysis revealed the presence of both high- and low-affinity binding sites in the MIPs. Selectivity experiments, quantified by distribution coefficients (K_d) and selectivity coefficients (k), demonstrated a significantly higher adsorption capacity for SDZ than for structural analogs and non-analogs. In real water samples, the MIPs outperformed conventional HLB sorbents and showed strong anti-interference capability (RSD < 3%). This work provides a material foundation for developing highly selective SDZ-imprinted membranes and advances the application of molecular imprinting technology in membrane separation systems. Full article

This study develops a kinetic model that captures poly-ether-ether-ketone (PEEK) crystallization over a temperature $T$ window from glass transition ($T_g$) to melting ($T_m$) temperature, and across cooling rates from 5 to ~10³ °C/min. The framework is a parallel dual-Nakamura formulation whose isokinetic parameters {$k_i\left(T\right),n_i,w_i\left(T\right)$} are obtained from a bi-level non-linear regression of isothermal crystallization tests conducted using a flash-differential scanning calorimeter (FSC). The weight $w_i\left(T\right)$ partitions the faster primary and slower secondary crystallization and is represented by a physics-based analytical function that captures its dome-shaped temperature dependence. A maximum isothermally achievable enthalpy function is introduced so that the model predicts enthalpy $\Delta H\left(t\right)$ natively under arbitrary thermal profiles. To extend this isothermal backbone to non-isothermal conditions, two explicit cooling-rate-dependent scalars are introduced, $\omega \left(\dot{T}\right)$ and $\chi \left(\dot{T}\right)$, which shift $w_i\left(T\right)$ and limit attainable crystallinity at high cooling rates respectively. Finally, a rate-dependent induction time relation is added to adjust the onset of crystallization. Calibrating these rate functions against non-isothermal experiments, while keeping the isokinetic parameters fixed, yields a single isothermal–non-isothermal model that predicts $\Delta H\left(t\right)$ under arbitrary $T\left(t\right)$ profiles. Model performance is validated using an interrupted FSC experiment with a multi-segment cooling program that mimics a local transient thermal history of PEEK during additive manufacturing. The sample is cooled through successive constant-rate segments with intermittent quench–remelt cycles to probe the accumulated crystallinity along the path. Without additional fitting, the model predicts the measured enthalpy evolution with R² ≈ 0.95. The framework thus provides a practical route for predicting polymer crystallinity under processing-relevant thermal histories. Full article

Alzheimer’s disease (AD) remains a significant global health challenge, highlighting the need for novel dual inhibitors targeting acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). This study investigated the trunk bark of Terminalia triptera Stapf. as a potential source of bioactive secondary metabolites for AD management. Bioassay-guided isolation led to the identification of two flavan-3-ol derivatives, epicatechin-(4β→8)-ent-catechin (1) and (−)-catechin (2), reported here for the first time from this species. In vitro assays demonstrated that the dimeric compound 1 exhibited stronger dual inhibitory activity against AChE and BChE, with IC₅₀ values of 4.41 × 10⁻⁴ and 4.75 × 10⁻⁴ mol/L, respectively, surpassing the reference compound berberine chloride. Molecular docking analysis revealed that compound 1 formed extensive interactions within both catalytic and peripheral anionic sites of the enzymes. Density Functional Theory (DFT) calculations indicated high kinetic stability, reflected by large HOMO–LUMO energy gaps (6.66–6.97 eV), while global reactivity descriptors suggested lower electrophilicity (ω = 2.19–2.34 eV), supporting a potentially favorable safety profile. Furthermore, 100 ns molecular dynamics simulations confirmed stable ligand–protein complexes stabilized by hydrogen-bond networks and deep binding within catalytic pockets. Overall, these findings highlight T. triptera and its dimeric proanthocyanidins as promising multi-target candidates for anti-Alzheimer drug development. Full article

High wind power penetration aggravates power system inertia scarcity, and wind turbines switching to MPPT mode after virtual inertia support induces secondary frequency drop (SFD), impairing grid frequency stability. Traditional energy storage system (ESS) sizing methods fail to couple wind turbine virtual inertia dynamics, rotor kinetic energy recovery and time-varying wind speeds, causing a trade-off between regulation performance and economy. To address this, an optimal ESS sizing method for wind-storage coordinated frequency regulation is proposed, including a doubly fed induction generator (DFIG) model for virtual inertia-power drop correlation, an incomplete compensation strategy, and a constrained three-objective optimization model co-optimizing virtual inertia and ESS parameters. The method, solved by NSGA-II with fuzzy membership functions, is validated on a 1000 MVA grid with a 245 MW DFIG wind farm. Results show it mitigates SFD, avoids ESS over-sizing, and balances performance and economy, breaking the decoupling between traditional ESS sizing and the virtual inertia dynamics of wind turbines. Full article

The closed kinetic chain is an essential movement method for humans in daily life, and is also important as a training method. However, there have been few studies focusing on the hip adductor muscles. We used electromyography to measure the muscle activity of the hip adductor muscles during walking and standing movements as part of daily living activities, as well as bicycle ergometer exercise and squats. Concerning the role of the adductor muscles, they are thought to stabilize the pelvis during the unilateral support phase when walking, and to act as hip extension and hip alignment adjustment during cycle ergometer exercise. By using electromyography and inertial sensors, the results of this study showed that wearable technologies can be used to quantify neuromuscular function during closed kinetic chain movements. The results serve as a reference for the development of rehabilitation devices, assistive technologies, and computational models that need the simulation of hip joint mechanics. Linking muscle activity data to engineering-based strategies enables precise musculoskeletal assessment and intervention beyond biological observation. Full article

Degradable polymers, such as poly(L-lactide) (PLLA), are widely investigated for biomedical applications, including drug delivery systems and temporary implants. Their functionality can be expanded by incorporating degradable metal microparticles that may influence degradation behaviour and enable additional surface modification strategies. In this study, the feasibility of composites consisting of PLLA and biodegradable iron microparticles was investigated. Composites were fabricated by solvent casting, providing a gentle alternative to thermal processing methods, which often compromise polymer integrity. Composites were evaluated by thermogravimetric analysis, differential scanning calorimetry, scanning electron microscopy (SEM), tensile testing, dynamic mechanical analysis, and X-ray photoelectron spectroscopy (XPS). Incorporation of iron altered thermal behaviour and crystallinity of PLLA, indicating interactions between polymer matrix and dispersed metal phase that may affect degradation kinetics and material stability. While iron addition reduced Young’s modulus, tensile strength, and elongation at break, composites maintained sufficient structural integrity for potential biomedical applications. XPS and SEM confirmed the embedding of particles within the polymer matrix, enabling potential post-processing approaches. In vitro direct contact and eluate tests demonstrated good cell viability, whereas exposure to free iron particles resulted in dose- and time-dependent cytotoxic effects. Overall, the results demonstrate the feasibility of solvent-cast PLLA–iron composites for resorbable biomedical applications. Full article

Microalgal and cyanobacterial biostimulants are increasingly recognized as sustainable tools for enhancing crop establishment and reducing dependence on synthetic agrochemicals. However, the strain-specific effects of many taxa on seed germination and early seedling development remain insufficiently characterized. This study evaluated the effects of seven microalgal and cyanobacterial suspensions on the germination kinetics and early seedling vigor of cucumber (Cucumis sativus L.). Several strains significantly accelerated germination and enhanced seedling performance relative to the control. Treatment with Coelastrella rubescens BCAC 301 S39, Scotinosphaera lemnae BCAC 113, Vischeria magna UTEX 2351, and Anabaena sp. IT4 significantly reduced mean germination time from 4.50 d to 2.23–2.29 d and advanced the time to 50% germination (T₅₀) from 4.0 to 2.0–2.1 d. These treatments also increased the germination index from 48.32 to 78.17–100.67 and enhanced seedling traits, including root length (32–53%), shoot length (≈29%), leaf length (17–21%), and fresh (30–43%) and dry biomasses (12–22%). Correlation analysis revealed strong positive associations between germination indices and seedling vigor parameters, indicating the faster germination promotes early growth. In conclusion, the results demonstrate that specific microalgal strains can function as effective seed-phase biostimulants, offering a sustainable strategy to enhance germination uniformity, early seedling establishment, and crop productivity. Full article

The food packaging industry requires sustainable solutions to reduce plastic waste and replace synthetic additives. This study addresses the need for scalable methods to transform conventional polyethylene terephthalate (PET) packaging into active food preservation systems using natural biocides. Commercial PET packaging was surface-activated using industrial-scale corona treatment, followed by coating with natural biocides—carvacrol (CV) and trans-cinnamaldehyde (tCN). The resulting active packaging materials (PET-CV and PET-tCN) were characterized using XRD, FTIR, SEM, AFM, and desorption kinetics. Packaging properties including mechanical strength, oxygen barrier, antioxidant (DPPH), and antibacterial activity (against S. aureus and E. coli) were evaluated. Real-food preservation tests were conducted using fresh minced pork (4 °C, 6 days) and table olives (23 °C, 21 days), monitoring microbiological (TVC), colorimetric (CIE L*a*b*), and pH changes. Corona treatment successfully anchored both biocides through physical adsorption, with tCN exhibiting stronger surface interaction (desorption energy: 128.0 kJ/mol). Both coatings significantly improved oxygen barrier properties (61% reduction for PET-CV, 80% for PET-tCN). PET-tCN demonstrated superior antibacterial activity (inhibition zones: 15.0 mm against E. coli). In pork preservation, PET-tCN achieved a 2-log reduction in TVC, maintained meat redness (a*: 12.80 vs. 5.10 for control), and stabilized pH. For olives, PET-tCN reduced TVC by 2.35 log cycles and preserved green color. This corona-assisted coating approach, demonstrated here at laboratory scale, successfully transforms inert PET into multi-functional active packaging with potent antimicrobial, antioxidant, and barrier properties, significantly extending food shelf-life and offering a sustainable solution for reducing food waste. Full article

This study developed an active packaging material by incorporating tea tree oil (TTO)-loaded lotus stalk biochar (BC@TTO) into a chitosan (CS) matrix. Biochar was prepared from lotus stalks via pyrolysis at 600 °C and characterized, revealing a mesoporous structure with a specific surface area of 35.9 m²/g. Adsorption studies demonstrated that BC exhibited high affinity for TTO, following pseudo-first-order kinetics and the Langmuir isotherm model, with a maximum adsorption capacity of 295.6 mg/g. Chitosan-based composite membranes with varying BC@TTO contents (1–7 wt%) were fabricated by solution casting. The incorporation of BC@TTO significantly enhanced the tensile strength, elongation at break, barrier properties (water vapor and oxygen), and antioxidant/antibacterial activities of the membranes, with optimal performance observed at 3 wt% loading. However, higher loadings led to filler aggregation, reduced transparency, and compromised mechanical properties. In vitro release studies indicated that TTO release followed the Avrami model, suggesting a diffusion-controlled mechanism. Preservation tests on blueberries showed that the CS-3BC@TTO membrane effectively reduced weight loss and maintained fruit quality during storage. This work presents a promising strategy for designing bioactive packaging materials with sustained release functionality for food preservation applications. Full article

The removal of water pollutants, specifically the organophosphorus pesticides chlorpyrifos (CHP) and azinphos-methyl (AZM), as well as the dye Rhodamine B (RB), was investigated through the valorization of grape pomace, an abundant agricultural byproduct. For the first time, hydrochars derived from grape pomace were utilized as adsorbents for these contaminants following KOH activation (HCK) and pyrolysis at 400 °C (PHC). The study aimed to evaluate the adsorption performance, determine the optimal conditions, and elucidate the adsorption mechanisms. Physicochemical characterization using SEM, FTIR, BET surface area analysis, stability, and pH_PZC measurements revealed distinct differences in surface morphology, functional groups, porosity, and surface charge. Under optimized conditions, maximum adsorption capacities reached 751.0, 3.98, and 1.39 mg g⁻¹ for RB, CHP, and AZM, respectively, on HCK, and 616.0 (RB), 30.10 (CHP), and 9.15 mg g⁻¹ (AZM) on PHC, indicating that the selected hydrochars efficiently removed the investigated pollutants from water. Kinetic modeling demonstrated pseudo-first-order adsorption for RB and CHP on HCK and pseudo-second-order adsorption for AZM on HCK and all pollutants on PHC. Thermodynamic analysis confirmed that adsorption processes were spontaneous and favorable, with enhancements dependent on temperature. These findings suggest that HCK is particularly effective for cationic dyes, while PHC exhibits greater affinity toward organophosphorus pesticides, offering complementary applications and providing new mechanistic insights into hydrochar-based pollutant removal. Full article

Background: Gene expression and cellular identity are regulated by epigenetics that occurs through chromatin modifications, RNA changes, chromatin accessibility, and three-dimensional genome organization. Although DNA methylation has been the focus of most epigenetics studies in the past, other non-methyl epigenetic processes, including histone post-translational modifications (PTMs), epitranscriptomic marks, and chromatin remodeling, are dynamic, reversible, and context-dependent, and thus are difficult to accurately interrogate using endpoint sequencing-based assays, especially in heterogeneous tissues, developing systems, and therapeutic response environments. Scope and Approach: The present review discusses epigenetic modifications other than DNA methylation regarding sensor-based technologies that can measure live, dynamic, and spatially resolved measurements. Epigenetic sensors include any genetically encoded sensors (GECs) based on resonance energy transfer, CRISPR/dCas-derived sensors, or aptamer-based sensors, and hybrid biochemical/imaging sensors that can be used in live or semi-live settings. It lays emphasis on the technologies, which have been developed recently, that allow real-time kinetic measurements, working in three-dimensional and organoid models, and being applied to disease-relevant perturbations. On these platforms, performance properties such as specificity, sensitivity, spatial and temporal resolution, ability to perform dynamic versus locus-specific interrogation, and perturbed endogenous chromatin states are compared. Key Conclusions and Outlook: Together, these sensing strategies are complementary to the traditional methods of measuring epigenomics in that they show epigenetic dynamics unobservable with static measurements. We list the important technical issues, including specificity, quantitation, multiplexing, and chromatin perturbation, and report the barriers and solutions in development and design. Lastly, we provide a conceptual map of how live epigenetic sensing and multi-omics and translational models can be integrated, and how the two methodologies can be used to develop functional epigenetics and guide disease modeling and drug development. Full article

Biopolymers such as chitosan are considered important candidates for water purification due to their non-toxicity, biodegradability, natural origin, biocompatibility, and potential for modification to provide additional capabilities, such as incorporating nanomaterials for magnetism to enable rapid separation or adding functional groups to enhance selectivity towards target adsorbates. This study investigated adsorption of Co (II), traced by Co-60 radionuclide, systematically evaluated in natural aquatic matrices selected according to water body type: seawater (Baltic Sea) and freshwater systems further distinguished as lentic (Lake Balsys) and lotic (Neris River) environments, using synthesized magnetite–chitosan nanocomposites (MCNs) with varying loadings of Fe₃O₄ (10–30 wt. %) nanoparticles providing different levels of magnetization. Comprehensive characterization (TEM, FTIR, AFM, XRD, and Mössbauer spectroscopy) confirmed successful integration of magnetite nanoparticles within the chitosan matrix and reproducible structural properties. An optimal magnetization of 11 emu/g was achieved at 20 wt. % Fe₃O₄, enabling rapid magnetic separation within <1 min without compromising sorption capacity. Adsorption isotherm models were applied to investigate the adsorption parameters, and sorption kinetics were studied, yielding a maximum adsorption capacity of 14.93 mg/g for MCN-10 in seawater and 11.95 mg/g for MCN-20 in freshwater with observed equilibrium within 120 min. These promising results indicate that the MCN is a suitable nanocomposite for the removal of Co (II) ions and the Co-60 radionuclide from aquatic media. Full article