Search Results (965)

Conductive core–shell superabsorbent polymers (SAPs) are emerging as multifunctional additives for cementitious materials, combining moisture management with electrical functionality. In cement-based systems, a swellable polymeric core enables internal curing and crack-sealing through controlled water uptake and release, while a conductive shell introduces ionic and/or electronic charge transport, addressing key limitations of conventional non-conductive SAPs. This dual functionality provides a pathway toward smart cementitious composites with enhanced durability, self-sensing capability, and moisture-responsive behavior. This review focuses on the physical chemistry mechanisms governing conductive core–shell SAPs in cementitious environments, with emphasis on swelling thermodynamics, water transport kinetics, interfacial phenomena, and charge transport mechanisms. The roles of osmotic pressure, elastic network constraints, ionic effects, and pore solution chemistry are critically discussed, together with their impact on conductivity, hydration processes, microstructure development, and long-term performance. The relative contributions of ionic and electronic conduction are examined in relation to hydration state, shell morphology, and percolation of conductive networks. In addition, the relevance of core–shell SAP architectures to sustainable packaging is briefly discussed as a secondary application, illustrating how similar physicochemical principles—such as moisture buffering and functional coatings—apply beyond construction materials. Finally, key knowledge gaps are identified, including long-term stability in highly alkaline environments, trade-offs between swelling capacity and conductivity, environmental impacts of conductive phases, and the need for integrated experimental and modeling approaches. Addressing these challenges is essential for the rational design and practical implementation of conductive core–shell SAPs in next-generation cementitious materials. Full article

This research evaluates the feasibility of using a lignocellulosic biosorbent prepared from mature leaves of Asplenium scolopendrium (produced through simple mechanical processing of the leaves, without applying any chemical modification or heat treatment) for the removal of methylene blue from water. Before and after adsorption the material was characterized using SEM technique and color analysis. Subsequently, the adsorption behavior was analyzed by examining equilibrium, kinetic, and thermodynamic aspects of the process. The equilibrium data were best represented by the Sips isotherm model, while the adsorption rate followed the Avrami model. Thermodynamic evaluation indicated that the retention of the dye occurs predominantly through a physical adsorption mechanism, while a minor contribution from chemisorption may be present, slightly enhancing the overall dye uptake. Process optimization was performed using the Taguchi experimental design, which also allowed the identification of the most significant operational variable. In addition, analysis of variance (ANOVA) was applied to quantify the contribution of each factor affecting dye removal efficiency. Among the investigated variables, time showed the strongest influence (72.65%), whereas temperature had a negligible effect (1.33%). The maximum adsorption capacity reached 174.1 mg/g, surpassing the performance of several comparable biosorbents reported in the literature. Overall, the findings demonstrate that Asplenium scolopendrium (hart’s-tongue fern) leaves represent an inexpensive, sustainable, and efficient material for eliminating methylene blue from aqueous solutions. Full article

Background/Objectives: Multidrug resistance (MDR) remains a major pathophysiological barrier to effective chemotherapy based on anthracyclines, including daunorubicin (DNR), in the treatment of leukemia. However, conventional population-level measurements of drug uptake do not resolve variability in uptake kinetics among individual leukemia cells, which may influence intracellular drug accumulation and therapeutic response. Methods: In this study, real-time DNR uptake was quantified at the single-cell level using a microfluidic biochip that enabled long-term cellular retention and continuous monitoring. Both wild-type drug-sensitive leukemia cells and a multidrug-resistant mutant overexpressing the P-glycoprotein (P-gp) efflux pump were examined. Results: Kinetic analysis revealed that DNR uptake in drug-sensitive cells was well described by a single dominant uptake process, whereas uptake in MDR cells required a model incorporating two kinetically distinct processes. In both cell populations, pronounced cell-to-cell variation was observed in uptake rates and intracellular drug retention, indicating substantial functional heterogeneity within phenotypically similar cells. This variability persisted following the treatment with an MDR inhibitor and obscured the differences between inhibitor-treated and untreated cells when the uptake was compared across different single cells. To overcome this limitation, a same-single-cell analysis (SASCA) approach was employed, enabling direct comparison of DNR uptake in the same individual cell before and after inhibitor exposure, thereby revealing enhanced intracellular DNR retention and accelerated uptake kinetics following inhibition. Conclusions: Together, these results demonstrate that real-time single-cell kinetic analysis reveals functionally relevant heterogeneity in multidrug-resistant leukemia cells and provides insight into the pathophysiology of MDR that cannot be obtained from population-averaged measurements. Full article

Phosphorus (P) availability is currently a limiting factor for agricultural production, especially in tropical soils, and its interaction with cationic micronutrients can significantly affect physiological efficiency and nutrient uptake by plants. Therefore, this study aimed to evaluate the uptake kinetic parameters described by the Michaelis–Menten model (Vmax, Km, and Cmin) for P as a function of the supply of Cu, Fe, Mn, and Zn, as well as the kinetic parameters of Cu, Fe, Mn, and Zn as a function of P supply in cotton (Gossypium hirsutum L.). The experiment was conducted in a greenhouse at the experimental unit of CENA, in Piracicaba, São Paulo, Brazil, using individual pots. Phosphorus concentration and accumulation were reduced only under Fe and Zn deficiency, with reductions of up to 60% in the shoots and 85% in the roots. Zn deficiency caused a drastic reduction in P uptake capacity, with Vmax decreasing from 590 to 50.85 µmol g⁻¹ h⁻¹ (approximately a 12-fold reduction), accompanied by an increase in Cmin (from 269 to 1508 µmol L⁻¹). In terms of micronutrient kinetics, P omission reduced plant growth and affected only Fe and Zn uptake. For Fe, Km increased from 12.82 to 27.31 µmol L⁻¹ and Cmin from 1.03 to 20.51 µmol L⁻¹. For Zn, and Vmax decreased from 0.16 to 0.02 µmol g⁻¹ h⁻¹ (approximately 8-fold), while Cmin increased from 0.08 to 1.56 µmol L⁻¹. These results demonstrate a strong interaction between P, Fe, and Zn, highlighting their regulatory roles in nutrient uptake and providing mechanistic insights into plant nutritional efficiency. Full article

Arsenic contamination, mainly in the arsenate (As(V)) form, continues to pose a serious threat to groundwater quality worldwide due to its long-term stability and toxicity at very low levels. Herein, we demonstrate, for the first time, a three-dimensional graphene oxide-based nanocomposite composed of Cu nanoparticle-doped, amino-functionalized UiO-66 (Cu/UiO-66-NH₂) anchored on a graphene oxide framework (Cu/UiO-66-NH₂@GO) as a novel and efficient nanosorbent for the rapid removal of As(V) in groundwater-like solutions. The nanocomposite was characterized by SEM and HRTEM to confirm the hybrid structure and by XRD, N₂ adsorption–desorption isotherms, and XPS to investigate crystallinity, porosity, and surface chemistry. The derived material exhibited a highly dispersed morphology and performed rapid arsenate solid-phase extraction to attain equilibration within 10 min and was effective for a wide pH range of 2–11. The best fit for the kinetic profiles was provided by the pseudo-second-order model. Interestingly, the maximum adsorption capacity of 747.9 mg g⁻¹ at pH 6.8 was achieved, demonstrating the benefits of the complementary pairing of dispersive GO sheets and Zr-MOF adsorption domains with Cu-derived active sites. Mechanistically, the enhanced uptake is ascribed to a combination of effects, including electrostatic pre-concentration, ligand exchange, and inner-sphere complexation at metal-oxo nodes; spectroscopic analysis (XPS and FTIR) suggests that the majority of arsenate is immobilized via a strong Zr-O-As bond at coordinatively unsaturated Zr centers, which is in line with t-ZrO₂-like surface domains formed within the nanocomposite. The embedded GO support inhibits further framework interpenetration and enhances active site availability and mass transport, leading to fast and high-capacity arsenate capture in groundwater samples with related conditions. Taken together, this work presents a powerful design concept that integrates unique GO-supported, Cu-modified UiO-66-NH₂ with Zr-O binding motifs to afford high-rate remediation nanocomposites, providing an excellent platform for next-generation arsenate remediation materials. Full article

Background: Transferrin receptor protein 1 (TfR1) plays a central role in cellular iron uptake and is frequently overexpressed in malignant tumor cells, rendering it an attractive target for tumor-directed therapy and drug delivery. Methods: A fully human single-chain variable fragment (scFv) antibody targeting TfR1, termed T8scFv, was isolated from a human scFv phage display library through three rounds of stringent biopanning and subsequently reformatted into a full-length IgG1 antibody (T8IgG1). Binding kinetics were characterized using Octet biolayer interferometry (BLI), while cellular binding and internalization were assessed by flow cytometry and immunofluorescence microscopy, respectively. T8IgG1 was further conjugated to DT3C, a recombinant truncated diphtheria toxin fusion protein, to evaluate its internalization-dependent cytotoxicity in vitro. Results: T8scFv exhibited nanomolar affinity for TfR1 (K_D = 214 ± 1 nM), which was substantially enhanced following conversion to the IgG1 format (T8IgG1, K_D = 18.5 ± 0.1 nM). T8IgG1 specifically recognized TfR1 on the surface of tumor cells and underwent efficient TfR1-mediated internalization. The T8IgG1-DT3C complex significantly reduced cell viability and induced apoptosis in K562 cells in vitro. Conclusions: These findings indicate that T8IgG1 is a moderate-affinity, internalizing anti-TfR1 antibody and highlight its potential as a promising candidate for TfR1-based targeted antitumor drug delivery systems. Full article

Objectives: Limited intracellular exposure can reduce the in vitro activity of pazopanib (PAZ) and enzalutamide (ENZ). This study developed bovine serum albumin (BSA) particles co-encapsulating PAZ and ENZ (PE-BSA) and evaluated physicochemical properties, release kinetics, 4T1 cellular uptake, and in vitro cytotoxicity versus free drugs and single-drug particles. Methods: Drug-loaded BSA particles were prepared using a crosslinking-based method. Particle size (PS), polydispersity index (PDI), zeta potential (ZP), and encapsulation efficiency (EE) were determined. In vitro release was assessed over 48 h and fitted to kinetic models. 4T1 uptake was quantified after 2 and 4 h by intracellular drug levels. Cytotoxicity was measured by MTT at 24 and 72 h (1–100 µg/mL). Moreover, cell death analyses were conducted. Stability studies at +4 °C and serum were also carried out. Results: PE-BSA was nanoscale and monodisperse (PS 128.7 ± 2.6 nm; PDI 0.026 ± 0.01) with ZP −31.65 ± 1.13 mV and high EE (PAZ 98.59 ± 1.78%; ENZ 69.79 ± 0.02%). At 24/48 h, cumulative release from PE-BSA was 11.96/12.31% for PAZ and 52.26/85.95% for ENZ. The release kinetics were best described by the Korsmeyer–Peppas model for PAZ (r² = 0.9578) and the Higuchi model for ENZ (r² = 0.9605), indicating diffusion-controlled release. PE-BSA increased 4T1 uptake versus free drugs (2 h: 10.02% PAZ and 21.9% ENZ; 1.77-fold and 4.15-fold), with sustained enhancement at 4 h (2.2- and 4.69-fold, respectively). After 24 h, PE-BSA induced a markedly higher apoptotic response in 4T1 cells (32.5% early apoptosis and 0.8% late apoptosis/early necrosis) compared with free-PAZ (6.6% early apoptosis) and P-BSA (7.3% early apoptosis). Particles were stable. Conclusions: PE-BSA produced BSA particles with diffusion-governed release and enhanced 4T1 internalization, supporting albumin particles as a delivery platform to increase intracellular exposure of PAZ/ENZ in vitro. Full article

Hydrogen absorption kinetics in metal hydride beds is constrained by coupled heat and mass transfer, which often leads to a slow refueling response and reduced storage system efficiency. In this work, hybrid molding by mixing silicone gel with various thermally conductive additives was used to prepare TiMn-based metal hydride beds with tailored porosity and thermal conductivity. Three experimental groups were prepared: 5 wt.% silicone gel and 5 wt.% single-walled carbon nanotubes (Group A), 5 wt.% silicone gel only (Group B), and 5 wt.% silicone gel and 5 wt.% silicone sheets (Group C). Hydrogen absorption kinetics at 30 °C and 50 bar were measured experimentally and simulated using a coupled heat-mass transfer model in COMSOL Multiphysics. The physical property results showed that Group A exhibited approximately threefold higher porosity (0.527) compared with the other two groups, while its thermal conductivity (2.476 W·m⁻¹·K⁻¹) was the lowest among them (3.189 W·m⁻¹·K⁻¹ for Group B and 3.246 W·m⁻¹·K⁻¹ for Group C). These property differences led to distinct hydrogen absorption rate-limiting behaviors. Group A dominated in the diffusion-controlled stage (hydrogen uptake between 0.5 and 1.15 wt.%) due to enhanced hydrogen transport through its macroporous network, while Group C exhibited faster kinetics in the later stage (above 1.15 wt.%), where thermal conductivity governed the absorption driving force. Numerical simulations reproduced the experimental kinetic curves and confirmed the transition of rate-limiting mechanisms. This work reveals that the rate-limiting factors of hydrogen absorption in hybrid molding hydride beds vary across different stages, and that independent optimization of porosity and thermal conductivity is required to achieve rapid kinetics across the entire absorption process. Full article

Cerium dioxide (CeO₂) has emerged as a structurally versatile oxide for dye-wastewater purification because its architecture, porosity, and surface accessibility can be tuned over a wide range while maintaining good chemical stability and environmental compatibility. Recent studies show that template-free or low-template routes can generate porous, mesoporous, multilayered, and flower-like CeO₂ architectures with rapid dye uptake and, in some systems, adsorption-assisted photocatalytic removal. However, CeO₂-based dye removal has often been discussed either within broad surveys of environmental applications or from composition-centered viewpoints, whereas the more fundamental question is how synthesis route controls architecture formation and how architecture, in turn, governs adsorption and subsequent removal behavior. This mini-review addresses that question from a morphology-centered perspective. It first examines template-free and low-template routes for constructing structured CeO₂, then discusses how porosity, hierarchical assembly, and surface accessibility regulate adsorption kinetics and equilibrium capacity in dye-containing aqueous systems. It further considers adsorption-assisted photocatalytic removal and argues that dark adsorption should be regarded as the structural first step rather than a secondary contribution. On this basis, the review shows that rare-earth doping in these systems is most usefully understood as a secondary tuning strategy that refines an already favorable host architecture by modifying surface interaction, optical response, or reactive-species generation. Overall, the available evidence indicates that CeO₂-based dye-wastewater purification is most meaningfully interpreted through a route–architecture–function framework in which morphology defines the host, adsorption organizes the local reaction environment, and doping serves mainly as structure-assisted tuning. This perspective shifts the design logic of CeO₂ from empirical performance optimization toward rational structure-directed construction of integrated removal platforms. Full article

Renal organic anion transporters 1 (OAT1) and 3 (OAT3) mediate the excretion of endogenous metabolites and xenobiotics. Flavonoids interact significantly with these transporters, but the structural determinants—especially regarding in vivo phase II metabolism—remain unclear. This review integrates recent cryogenic electron microscopy (cryo-EM) structural biology and transporter kinetics to delineate the molecular basis of flavonoid–OAT interactions. We highlight phase II metabolites as key in vivo effectors. Structurally, OAT1 strictly favors compact, planar anionic scaffolds, whereas OAT3 accommodates bulkier, conjugated forms. Crucially, flavonoids exert a “double-edged” toxicological effect: high-affinity OAT inhibition risks herb–drug interactions, yet competitively limits the tubular uptake of nephrotoxins. Furthermore, disease states and post-translational regulation reshape these interactions. By bridging structural insights with biomarker-guided pharmacokinetics, we propose a mechanistic framework to improve the precise safety assessment of flavonoid-containing therapeutics. Full article

This report investigates the capacity of crystal violet (CV) uptake from aqueous solutions by a sulfonated gel (Sulfo-Gel) made via free radical polymerization of acrylamide and sulfonic monomer (3-Allyloxy-2-hydroxy-1-propanesulfonic acid sodium salt). CV uptake was examined through a batch technique, assessing the effects of various conditions, including uptake time, solution pH, gel dose, initial concentration of dye, and temperature. Results showed that the hydrogel adsorbent removed 74.88% of the CV dye at a gel dose of 500 mg/L in a neutral medium at initial CV concentration of 30 mg/L and contact time 100 min. The adsorption kinetics were best depicted by nonlinear fitting of pseudo-first-order model. Additionally, adsorption isotherms were analyzed using nonlinear fitting of the Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich models, with the data fitting the Temkin model most effectively. Thermodynamic studies signified the exothermic nature of the adsorption process and its spontaneity. Full article

Ruthenocene (Rc) and its derivatives form a structurally versatile class of metallocenes with unique and multifunctional applicability. This review presents a detailed analysis of Rc chemistry including the structural comparison with ferrocene, its redox behavior, and substituent effects. We also discuss its applications in sensing, energy storage, photochemistry, and biomedicine. Rc exhibits unique conformational and adaptive electronic properties based on one and two-electron oxidation processes. Electrochemical investigations of Rc to date indicate that its redox behavior is strongly dependent on the electrolyte system, exhibiting quasi-Nernstian characteristics, the formation of stabilized dimeric species [Rc₂]²⁺, and interconversion among Ru(II), Ru(III), and Ru(IV) oxidation states. Rc-based systems exhibit superior performance as redox mediators and labels in electrochemical sensing systems in terms of electron-transfer kinetics, signal amplification, and surface immobilization. In the field of energy storage, Rc decreases the charging overpotential and increases the cycle life of Li-O₂ batteries. Rc further acts as a photoinitiator via charge-transfer-to-solvent and efficient photoinduced electron transfer in metalloporphyrin and fullerene dyads. In biomedical research, Rc derivatives as well as bioconjugates possess promising anticancer activities, displaying reactive oxygen species generation, topoisomerase inhibition, thioredoxin reductase inhibition, receptor-mediated uptake, and target peptide conjugation. Given its flexible ligand design, electrolyte driven redox behaviors, and antiproliferative properties, Rc exhibits a very adaptive molecular scaffold for next generation electrochemical technologies as well as metallodrug design. Full article

Phthalate esters (PAEs) are ubiquitously emerging pollutants in the environment and have a notably high detection rate in tea; they can leach out during consumption and pose potential risks to human health. However, the process of PAEs entering and accumulating in tea plants is undocumented. This study investigated the uptake of PAEs in tea plant seedlings, focusing on both root and foliar pathways under hydroponic conditions. In controlled indoor deposition experiments, PAEs on fresh tea leaves underwent rapid degradation within five days, with the degradation rates ranging from 66.98% to 81.69%; outdoor rates exhibited even higher degradation rates. This degradation process followed first-order kinetics. The results revealed that tea plants were capable of absorbing and translocating PAEs via roots and leaves, culminating in their accumulation in various tea plant tissues. The Root Concentration Factor (RCF) was highest for di(2-ethylhexyl) phthalate (DEHP). Conversely, the shoot concentration factor, Leaf Concentration Factor, and Translocation Factors for the leaves, stems, and roots for the PAEs were inversely related to the RCF. The moderated mediation analysis suggested that root concentration was strongly influenced by translocation-mediated pathways. However, leaf concentration was largely not mediated by the translocation pathways. These findings indicate that both root uptake and foliar deposition can contribute to PAE accumulation in tea plants, providing a basis for source apportionment and for designing targeted control strategies to reduce PAE contamination in tea production systems. Full article

Nanomaterials are emerging versatile platforms for therapeutic delivery, as they offer precise control over drug, antioxidant, and genetic payload transport across biological barriers. Inorganic, organic, hybrid, and biomimetic systems are the major classes of nanomaterials, which all have different physicochemical properties such as size, surface charge, and surface functionalization. These properties collectively influence stability, biodistribution, cellular uptake, and release kinetics. Engineering strategies are increasingly using stimuli-responsive designs that are triggered by pH, reactive oxygen species (ROS), and intracellular redox gradients to perform spatially and temporally controlled delivery. Antioxidant and redox-modulating nanocarriers are of great importance as they overcome the limited bioavailability and nonspecific activity of conventional antioxidants by improving stability, targeting oxidative microenvironments, and allowing for regulated release. Improvements in lipid, polymeric, and inorganic nanoplatforms have also developed gene delivery applications, including siRNA, mRNA, and CRISPR/Cas systems, to provide better cytosolic release and precise therapeutics. When diagnostic imaging is integrated with therapy through theranostic nanoparticles, real-time monitoring and personalized intervention are possible. Safety, scalable manufacturing, and regulatory alignment are some challenges that show the need for standardization and translational procedures to utilize the potential of theranostic nanomedicine. Full article

Excess post-exercise oxygen consumption (EPOC) reflects cardiorespiratory fitness, energy metabolism and the residual physiological effects of preceding exercise. We aimed to compare EPOC profiles of master swimmers across different age groups and performance levels. Fourteen male master swimmers performed a 200 m all-out front crawl and breath-by-breath gas exchange and their heart rates were recorded during exercise and for 5 min post-exercise. A single exponential regression model was fitted to the post-exercise oxygen uptake kinetics to determine the EPOC amplitude, time constant and time delay. The EPOC magnitude was calculated as the area under the oxygen uptake–time curve. Swimmers were grouped into younger vs. older and faster vs. slower clusters using the 50th percentile, and the associations between age, performance and physiological variables were examined. Older swimmers were slower and showed a lower peak oxygen uptake than their younger counterparts (213.9 ± 27.9 vs. 165.7 ± 24.9 s and 39.1 ± 4.8 vs. 50.2 ± 8.1 mL∙kg⁻¹∙min⁻¹; p < 0.05). Slower swimmers were older and displayed a lower EPOC amplitude than faster performers (69.8 ± 7.3 vs. 45.7 ± 1.7 years and 23.2 ± 4.0 vs. 36.8 ± 10.2 mL∙kg⁻¹∙min⁻¹; p < 0.05). Although many of the variables did not differ between groups, effect sizes were moderate to very large (except for time constant and time delay). The swimmers’ age related directly to their performance and inversely to their peak oxygen uptake, peak heart rate and EPOC amplitude, while performance presented inverse associations with peak oxygen uptake, peak heart rate, EPOC amplitude and EPOC magnitude (p < 0.05). Master swimmers of different ages and performance levels exhibited distinct EPOC characteristics, which may provide relevant information regarding the individualisation of training and recovery strategies in this population. Full article