Search Results (1,091)

Bentonite is the most widely used raw material for producing organoclays, which have numerous industrial and environmental applications. Due to their hydrophobicity, high swelling, and strong affinity for organic compounds, organoclays are effective in removing organic solvents from contaminated water originating from pipeline leaks, oil spills, traffic accidents, and industrial discharges. Such contamination not only degrades water quality but also forms surface films that hinder oxygen transfer, threatening aquatic ecosystems. In this study, two sodium bentonites with different specific surface areas (30 and 50 m²/g) were modified with three quaternary ammonium salts of varying molar masses and alkyl chain lengths (Sun, Arq, and Arm) to evaluate their performance in organic solvent sorption (gasoline, diesel, and kerosene). The materials were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential thermal analysis (DTA), scanning electron microscopy (SEM), and swelling capacity and sorption efficiency. The swelling capacity was determined according to ASTM D5890-19 (Foster method) using gasoline, diesel, kerosene, toluene, and xylene, while the sorption efficiency was assessed following ASTM F726-17 in gasoline, diesel, and kerosene, chosen due to their high potential for water contamination and frequent occurrence in oil spill and leakage scenarios. These solvents also differ in polarity and aromatic content, providing a relevant model for hydrocarbon mixtures commonly found in the environment. Results showed that the interaction between the clay and the surfactant depended strongly on the modifier’s chemical structure. The sorption capacity increased with greater interlayer expansion, surfactant molar mass, and specific surface area of the clay. Among all samples, the Arm-modified natural bentonite (VLArm) exhibited the best performance, with adsorption capacities of up to 6 g/g for diesel, 5 g/g for gasoline, and 5 g/g for kerosene. These values exceeded most previously reported organoclays. These findings demonstrate that optimizing the combination of clay properties and surfactant chemistry can yield highly efficient, low-cost organoclays for environmental remediation of organic contaminants. Full article

This study employed urea (U), acrylamide (AM), and choline chloride (ChCl) as raw materials to synthesize a deep eutectic solvent (DES), incorporated dispersed Fe₃O₄ as a filler within the DES, and effectively fabricated Fe₃O₄/P(U-AM-ChCl) composite hydrogels through in situ polymerization (SP). The hydrogels were analyzed through Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The influence of different Fe₃O₄ contents on the swelling behavior, anti-fatigue properties, and adsorption efficiency of the composite hydrogels was thoroughly examined. The results indicated that, in comparison to the hydrogel lacking Fe₃O₄, the hydrogel containing 1 wt% Fe₃O₄ demonstrated enhanced swelling and anti-fatigue characteristics, with its equilibrium swelling ratio (ESR) increasing by 16.34%, the time to achieve swelling equilibrium decreasing by 60%, the maximum stress recovery rate rising by 7.8%, and the toughness recovery rate improving by 7.28%.The adsorption efficiency of the hydrogel was improved, and adsorption equilibrium was achieved more quickly, due to the supplementary adsorption sites introduced by Fe₃O₄. When the Fe₃O₄/P(U-AM-ChCl) composite hydrogel was immersed in a 120 mg/L Cu²⁺ so-lution for 48 h, the adsorption capacity reached 171.5 mg/g. This study introduces a novel, viable approach for synthesizing hydrogels with reduced pore sizes and enhanced functionality, while also illustrating their prospective utility in water purification applications. Full article

Background/Objectives: In recent years, it has been suggested that sedatives may cause brain damage. One possible mechanism is interference with oxidative phosphorylation of brain mitochondria, but much remains unknown. In this study, we focused on dexmedetomidine, midazolam, and propofol, essential sedatives in anesthesia and intensive care, and aimed to understand the effects of these drugs on mouse brain mitochondria. Methods: We measured changes in mitochondrial respiratory capacity and swelling rate upon exposure to these sedatives in a wide concentration range. For the sedative that demonstrated impaired mitochondrial function we explored the possible involvement of mitochondrial permeability transition pore opening using brain mitochondria from cyclophilin D knockout (CypD KO) mice and detected cytochrome c (cyt c) release by Western blot. Results: Of the three sedatives, only high concentrations of propofol exhibited reduced respiratory capacity and mitochondrial swelling, toxicity which was not prevented by CypD KO. Furthermore, propofol did not induce cyt c release. Conclusions: These results suggest that propofol-induced brain mitochondrial dysfunction is a mechanism independent of mPTP opening. Full article

Climate change and the impacts related to nonbiodegradable synthetic materials highlight the need for sustainable alternatives. Biopolymers from renewable sources show great potential for producing hydrogels, which are three-dimensionally crosslinked materials with high water absorption. In this work, super-absorbent biodegradable hydrogels were produced via single-step reactive extrusion using mixtures of starch, gelatin, cellulose, and xanthan gum, with glycerol as a plasticizer, and citric acid as a crosslinking agent. Pelleted hydrogels were obtained with water absorption between 290% and 363%. Reactive extrusion promoted the formation of new ester and amide bonds, confirmed by FT-IR. Citric acid was effective as a crosslinker, and higher citric acid content (3%) produced samples with greater swelling, supported by the porous internal structure observed. Preliminary agricultural tests showed that the formulation with the highest citric acid content, when added to soil at 5%, significantly increased water-holding capacity and resulted in the highest germination rate of maize seeds. Overall, the extrusion process proved efficient, scalable, and environmentally friendly for producing biodegradable hydrogels for agricultural applications. Full article

The increasing prevalence of celiac disease and demand for nutritious gluten-free alternatives have driven interest in cereal–legume composite flours. This study examined the functional, rheological, and textural properties of gluten-free flour blends formulated from brown (red) teff (Eragrostis tef (Zucc.) Trotter) and soybean (Glycine max (L.) Merr.) at different ratios (100:0, 90:10, 80:20, 70:30, 60:40, 0:100). Absorptive characteristics, particle size distribution, pasting behaviour, viscoelastic properties through oscillatory rheology, and texture profile analysis were evaluated. Soybean flour exhibited higher water holding capacity (5.54 g/g) and water solubility index (40.18%), while teff demonstrated notable water absorption index (5.62 g/g) and swelling power (6.18 g/g). Particle size analysis revealed that coarse fractions enhanced water binding and solubility, whereas fine fractions favoured hydration and swelling. Pasting properties showed that teff achieved a peak viscosity of 12,198 mPas in water, significantly reduced to 1839 mPas with AgNO₃. Pure teff exhibited the highest storage modulus (1947.98 Pa) and hardness (7.60 N), whereas the incorporation of soybeans progressively softened the texture. The complementary functional properties of teff and soybean demonstrate promising potential for developing nutritionally enhanced, protein-enriched gluten-free products, with solvent selection and blending ratios serving as critical optimization parameters for specific food applications. Full article

This study presents an energy-efficient, room-temperature synthesis and characterization of methacrylated pullulan (Pull-MA) hydrogel developed for controlled nutrient delivery in agricultural applications. Fourier Transform Infrared Spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC) analyses confirmed the successful functionalization of pullulan with methacrylate groups, accompanied by a decrease in thermal transition temperatures, indicative of increased polymer chain mobility. The synthesized Pull-MA hydrogel exhibited a high swelling capacity, reaching an equilibrium swelling ratio of 1068% within 5 h, demonstrating its suitability as a carrier matrix. The room-temperature synthesis approach enabled the in situ incorporation of microbial inoculant into the hydrogel network, preserving microbial viability and activity. SEM analysis performed under the different magnifications (1000, 2500, 5000, 10,000, 25,000×) has confirmed brittle nature of xerogels and increasing in structural irregularities with increasing in cultivation broth content.The biological performance of the fertilizer-loaded hydrogels was evaluated through seed germination assays using maize and pepper as model crops. The optimized formulation, T2 (Pull-MA: cultivation broth 1:5 w/w), significantly improved germination efficiency, as evidenced by increased relative seed germination (RSG), root growth rate (RRG), and germination index (GI) compared to both the control and the low-fertilizer formulation (T1, 1:2.5 w/w). These findings highlight the potential of Pull-MA hydrogels as bioactive seed-coating materials that enhance early seedling development through controlled nutrient release. The results lay a solid foundation for further optimization and future application of this system under real field conditions. Full article

The study was conducted to determine the apparent total tract digestibility, the rate of digesta passage, growth performance, and physicochemical properties of the digesta of Windsnyer pigs fed on increasing levels of potato hash silage. Diets were formulated to contain 0, 80, 160, 240, 320, and 400 g potato hash silage/kg of diet. Pigs were randomly assigned to six diets according to a completely randomised design. Six pigs were allocated to each dietary treatment. All diets were blended with chromic oxide (Cr₂O₃) to calculate apparent total tract digestibility and rate of passage. Pigs were fed diets containing different levels of potato hash silage for 5 d, following 7 d of adaptation. Thereafter, pigs were subjected to a 35-day growth performance experiment. Thirty-six pigs were slaughtered and eviscerated to determine digesta characteristics and gut compartment weights. There was a positive correlation (p < 0.05) between mean retention time and each of digestibility of dry matter, organic matter, and crude protein. There was a quadratic increase (p < 0.05) in digestibility of organic matter, crude protein, fibre and feed intake as dietary levels of potato hash silage increased. Average daily gain and gain-to-feed ratio decreased linearly (p < 0.05) in pigs as levels of potato hash silage increased. The swelling capacity (SWC) of the digesta from ileum decreased linearly (p < 0.05) as dietary levels of potato hash silage increased. The SWC of the digesta from the caecum increased linearly (p < 0.05) as dietary levels of potato hash silage increased. The water holding capacity (WHC) of the stomach digesta decreased linearly (p < 0.05) as dietary levels of potato hash silage increased. The WHC of the digesta from the ileum and caecum displayed negative quadratic responses (p < 0.05) as dietary levels of potato hash silage increased. The WHC of digesta from the proximal colon showed a linear decline (p < 0.05) as dietary levels of potato hash silage increased. The WHC of digesta from the distal colon increased linearly (p < 0.05) as dietary levels of potato hash silage increased. The results indicated that Windsnyer pigs can effectively utilise potato hash silage in diets until the 240 g/kg inclusion level beyond which total tract digestibility and feed intake are compromised. Full article

Guamuchil (Pithecellobium dulce) is an underutilized legume with significant potential as a food ingredient. This study valorized guamuchil fractions (pulp, peel, and seed) by developing dietary fiber concentrates (DFC) and evaluating their physicochemical, techno-functional, and antioxidant properties using a single-factor completely randomized design. Proximate composition and dietary fiber profiles (2011.25) were analyzed following AOAC official methodologies. Results showed the peel fraction contained the highest total dietary fiber (64.16 ± 1.23 g 100 g⁻¹ dry basis (db)) and total phenolic content (15.46 ± 0.26 mg GAE g⁻¹ db), positioning it as a bioactive fiber source. Conversely, the pulp DFC exhibited superior hydration properties, with high solubility (43.54 ± 1.22%), swelling (10.23 ± 0.30 mL g⁻¹ db), and water retention capacity (14.17 ± 0.35 mL g⁻¹ db), making it suitable as a texturizer. Moisture sorption isotherms exhibited type II sigmoidal behavior, accurately fitted by GAB and Peleg models (R² ≥ 0.997). The pulp showed higher hygroscopicity and water binding ability, whereas peel and seed fractions displayed lower sorption and enhanced stability. These findings demonstrate that Guamuchil DFCs are suitable as a potential food formulation ingredient owing to their high functionality. Full article

The paper analyses the effect of the solvent amount and nature on the structure and mechanical properties of hydrogels based on copolymers of 2-hydroxyethylmethacrylate (HEMA) with polyvinylpyrrolidone (PVP). The synthesis of pHEMA-gr-PVP copolymers was carried out by the copolymerization method in the presence of metal ions of variable oxidation states in solvents with various nature: water, dimethyl sulfoxide (DMSO), diethylene glycol (DEG), and cyclohexanol (HOCy). The structure of the copolymers was evaluated by the PVP grafting efficiency, its actual content in the copolymer, and the molecular weight between crosslinks (M_C). Taking the example of water, an increase in the solvent content up to 50 mass parts causes an increase in the efficiency of PVP grafting, which occurs due to enhanced macromolecule mobility through the dilution of the starting composition, hence the decrease in its viscosity. It was established that the nature of the solvent significantly affects the crosslinking density of the polymer network in the series H₂O, DEG, DMSO, HOCy, an increase in the M_C is observed causing a decrease in the hardness and elasticity of hydrogels and an increase in their water-retention capacity and swelling coefficient. The obtained results prove the possibility of targeted regulation within wide limits of the structure and properties of hydrogels based on pHEMA-gr-PVP copolymers through control of polymerization conditions (selection of the type and concentration of solvent). Full article

This study investigates the impact of ultrasonic treatment on the deagglomeration of aggregates of single-walled carbon nanotubes (SWCNTs) and reduced graphene oxide (rGO). The aim of the research is to enhance the electrical conductivity of a biopolymer hydrogel designed for coating metallic neurostimulation electrodes. Biocompatible coating materials are essential for the safe long-term function of implants within the body, enabling the transmission of nerve impulses to external devices for signal conversion and neurostimulation. Dynamic light scattering (DLS) was employed to monitor the dispersion state, in conjunction with measurements of specific electrical conductivity. The mass loss and swelling capacity were evaluated over an 80-day period to account for the effects of degradation during in vitro studies. Samples of flexible–elastic hydrogels for electrodes with complex geometry were formed by the photopolymerization of a photopolymerizable medium, similar to a photoresist. Analysis of the dependence of temperature and normalized optical transmittance on the duration of laser photopolymerization made it possible to determine the optimal polymerization temperature for the photopolymerizable medium as −28 °C. This temperature regime ensures maximum reproducibility of hydrogel formation and eliminates the presence of unpolymerized areas. The article presents a biopolymer hydrogel with SWCNTs and rGO nanoparticles in a 1:1 ratio. It was found that sufficient specific electrical conductivity is achieved using SWCNTs with a characteristic hydrodynamic radius of R = 490 nm and rGO with R = 210 nm (sample Col/BSA/CS/Eosin Y/SWCNTs (490 nm)/rGO 4). The photopolymerized hydrogel 4 demonstrated sufficient biocompatibility, exceeding the control sample by 16%. According to the results of in vitro studies over 80 days, this sample exhibited moderate degradation of 45% while retaining its swelling ability. The swelling degree decreased by 50% compared to the initial value of 170%. The presented hydrogel 4 is a promising coating material for implantable metallic neurostimulation electrodes, enhancing their stability in the physiological environment. Full article

Expansive soils undergo significant volume changes with moisture fluctuations, posing persistent challenges for infrastructure due to heave, settlement, and loss of bearing capacity. Stabilization is a common mitigation strategy, though traditional binders, such as cement and lime, are associated with high energy consumption and considerable CO₂ emissions. In this context, identifying low-carbon alternatives is essential. This study evaluates the short-term behavior of expansive marly clays from southern Spain stabilized with volcanic ash generated during the 2021 Tajogaite eruption (La Palma, Canary Islands, Spain). Volcanic ash was incorporated in different proportions to assess its performance as a natural pozzolan, while natural hydrated lime was used both as a direct stabilizer and as an activator to enhance ash reactivity. A key methodological contribution of this research is the monitoring of lime reactivity throughout storage, using XRD and TGA to quantify portlandite loss and partial carbonation before mixing—an aspect seldom addressed in stabilization studies. The experimental program included chemical and mineralogical characterization, compaction, Atterberg limits, free swelling, unconfined compressive strength, and direct shear tests on natural and stabilized mixtures. The results show that volcanic ash, particularly when lime-activated, substantially improves volumetric stability. Free swelling decreased from 11.9% in the natural soil to values as low as 1.7%, while dry density increased and plasticity decreased. Strength gains were modest under short-term conditions, consistent with the limited time for pozzolanic reactions to develop. The combined use of volcanic ash and lime reduced the lime demand required to achieve equivalent volumetric control, offering an eco-efficient and technically viable alternative for stabilizing expansive marly clays. Full article

Background/Objectives: The ABCG2 transporter actively effluxes anticancer drugs, reducing their efficacy and promoting multidrug resistance (MDR). Developing oral formulations of poorly soluble ABCG2 inhibitors remains challenging due to their low solubility and intestinal permeability. This study aimed to formulate and evaluate an ABCG2 inhibitor using micro- and nanoscale drug delivery systems. Methods: To address the poor solubility and bioavailability of the corresponding active ingredient, a self-nanoemulsifying drug delivery system (SNEDDS) was developed. The SNEDDS was encapsulated into microcapsules using sodium alginate crosslinked with calcium chloride. Five microcapsule formulations were developed, varying in the inclusion of polyvinylpyrrolidone (PVP), Transcutol^® HP and SNEDDS. The effects of the excipients on encapsulation efficiency, swelling capacity, enzymatic stability, dissolution, cytocompatibility, and permeability were systematically evaluated. Results: The SNEDDS exhibited monodisperse particle sizes and efficient drug entrapment. Results revealed that formulations incorporating PVP and SNEDDS improved encapsulation efficiency and bioavailability. SNEDDS-containing formulations demonstrated superior enzymatic stability in simulated gastric and intestinal fluids and provided the highest cumulative drug release in vitro. Cytotoxicity studies conducted on Caco-2 and MCF-7 cells demonstrated that our formulations were well tolerated, indicating favorable biocompatibility. Conclusions: Our findings demonstrate that SNEDDS-loaded alginate microcapsules offer an efficient platform for oral delivery of dimeric ABCG2 inhibitors, combining enhanced solubility, stability, and controlled release. The optimized formulation can be regarded as a promising strategy to enhance the oral bioavailability of efflux pump inhibitors and other poorly soluble drugs. Full article

Porous starch (PS) is widely used in food, pharmaceutical, and environmental industries for its high adsorption capacity and controlled release properties. To explore how surface gelatinization affected enzymatically prepared PS, corn starch was first modified via surface gelatinization using a CaCl₂ solution and then treated with α-amylase and amyloglucosidase to synthesize PS. Its structural and functional characteristics were subsequently analyzed. The findings demonstrated that the CaCl₂ solution facilitated the surface gelatinization and enhanced the enzymatic hydrolysis of natural starch. The yield, specific volume, water solubility, swelling power, and oil absorption capacity of PS pretreated with CaCl₂ solution were improved. After 40 min of processing, the yield, specific volume, and oil absorption capacity of PS reached the optimal state, increasing by 19.90%, 91.19%, and 32.84%, respectively. Consequently, its fisetin encapsulation efficiency (93.67%) and loading capacity (8.03%) were also higher than those of non-pretreated PS, attributed to the reduced short-range structure and crystallinity in the CaCl₂-pretreated PS. The DPPH and ABTS radical scavenging activities of CaCl₂-pretreated PS/fisetin (PS/FIT) exceeded those of the non-pretreated PS/FIT and free fisetin. These findings highlight the potential of CaCl₂ pretreatment as an effective strategy to enhance the functional properties of enzymatic PS. Full article

Gelatin-based hydrogels are promising materials for pharmaceutical and biomedical applications due to their biocompatibility, biodegradability, and tunable gel-forming behavior. However, their thermo-sensitivity and limited processability often restrict their practical use in advanced drug delivery or tissue engineering systems. In this study, low-molecular-weight gelatin (LMWG) was obtained from native gelatin through controlled degradation with hydroxylamine, aiming to enhance processability while maintaining functional amino groups for crosslinking. Hydrogels prepared from both native gelatin and LMWG were crosslinked with genipin, a natural and biocompatible compound, and comprehensively characterized in terms of structural, mechanical, and biological properties. LMWG exhibited superior processability, remaining liquid at room temperature, which facilitates the preparation of different formulations and the potential incorporation of bioactive compounds into the crosslinked hydrogels. Compared with gelatin-genipin hydrogels, LMWG-genipin hydrogels showed higher swelling capacity, slightly increased porosity, and improved flexibility without significant loss of mechanical integrity. Rheological analysis confirmed both hydrogels’ viscoelastic properties with differences in their thermo-sensitive behavior. Cytocompatibility assays using L929 fibroblasts demonstrated low toxicity as well as proliferation of cells seeded on the materials. Overall, the combination of molecular weight modulation and crosslinking by genipin provides a simple and effective strategy to develop gelatin-based hydrogels suitable for pharmaceutical formulations, tissue-engineering scaffolds, and controlled-release systems. Full article

In the present study, alginate–silver nanoparticle (Alg-AgNP) nanocomposite hydrogels possessing antibacterial activity were synthesized via an innovative route. A task-specific designed Natural Deep Eutectic Solvent (NADES), composed of glucose, lactic acid, and water, was utilized as a green extraction solvent of bioactive compounds from olive leaves (OLs). The NADES–olive leaf extract (NADES-OLE) was used as obtained for the preparation of the Alg-AgNP nanocomposite hydrogel as a multiple-role component. The NADES-OLE acts (a) as a crosslinking agent for the preparation of the alginate hydrogels, (b) as a reducing agent for the in situ synthesis of AgNPs during hydrogel formation, and (c) as a bioactivity enhancement agent due to the presence of compounds obtained from the olive leaves. The Alg-AgNP hydrogel preparation process was optimized through a Box–Behnken experimental design. The resulting nanocomposite hydrogels were characterized for their swelling capacity and water retention in phosphate buffer (pH 5.5), achieving 538% swelling capacity within 180 min and 90% water retention after 250 min. The AgNPs formed within the hydrogels were found to have an average size of 103.2 ± 5.6 nm, with a concentration of 1.2 10⁸ ± 2.2 ∗ 10⁷ particles/mL. Antibacterial testing of the nanocomposite hydrogels against foodborne pathogens, including Gram-negative (Escherichia coli, Salmonella Typhimurium, Yersinia enterocolitica) and Gram-positive bacteria (Listeria monocytogenes, Staphylococcus aureus, Bacillus cereus), revealed significant antibacterial activity, particularly against E. coli (64.9%), Y. enterocolitica (60.6%), S. aureus (79.1%), and B. cereus (55.3%), at a concentration of 1 mg/mL. Full article