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1.
PLoS One ; 19(5): e0301581, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38768168

RESUMEN

Research is ongoing to find solutions to the problem of Consolidation and seepage in saturated clay in enclosure space. Firstly, the boundary of non-zero-constant values is established, considering the seepage boundary of the clay is affected by pumping water or lowering boundary pressure on the site. Secondly, the differential equation is established to reflect the spatial and temporal variations of excess pore water pressure dissipation in the clay in enclosure space, and the solution is derived using variable separation methods. Finally, based on results of the solution derived, contour maps of the water pressure are drawn corresponding with the different inhomogeneous boundary conditions.


Asunto(s)
Arcilla , Arcilla/química , Agua/química , Presión , Modelos Teóricos , Silicatos de Aluminio/química , Soluciones
2.
J Chromatogr A ; 1725: 464943, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38691924

RESUMEN

In this study, we proposed a novel method utilizing polyethyleneimine (PEI)-modified halloysite nanotubes (HNTs)-based hybrid silica monolithic spin tip to analyze hydrophilic ß-lactam antibiotics and ß-lactamases inhibitors in whole blood samples for the first time. HNTs were incorporated directly into the hybrid silica monolith via a sol-gel method, which improved the hydrophilicity of the matrix. The as-prepared monolith was further modified with PEI by glutaraldehyde coupling reaction. It was found that the PEI-modified HNTs-based hybrid silica monolith enabled a large adsorption capacity of cefoperazone at 35.7 mg g-1. The monolithic spin tip-based purification method greatly reduced the matrix effect of whole blood samples and had a detection limit as low as 0.1 - 0.2 ng mL-1. In addition, the spiked recoveries of sulbactam, cefuroxime, and cefoperazone in blank whole blood were in the range of 89.3-105.4 % for intra-day and 90.6-103.5 % for inter-day, with low relative standard deviations of 1.3-7.2 % and 4.9-10.5 %, respectively. This study introduces a new strategy for preparing nanoparticles incorporated in a hybrid silica monolith with a high adsorption capacity. Moreover, it offers a valuable tool to monitor sulbactam, cefoperazone, and cefuroxime in whole blood from pregnant women with the final aim of guiding their administration.


Asunto(s)
Cefoperazona , Cefuroxima , Interacciones Hidrofóbicas e Hidrofílicas , Límite de Detección , Nanotubos , Dióxido de Silicio , Extracción en Fase Sólida , Sulbactam , Cefoperazona/sangre , Cefoperazona/química , Humanos , Sulbactam/sangre , Sulbactam/química , Extracción en Fase Sólida/métodos , Dióxido de Silicio/química , Nanotubos/química , Cefuroxima/sangre , Cefuroxima/química , Arcilla/química , Adsorción , Antibacterianos/sangre , Antibacterianos/química , Polietileneimina/química , Cromatografía Líquida de Alta Presión/métodos , Reproducibilidad de los Resultados
3.
J Phys Chem Lett ; 15(19): 5295-5305, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38722703

RESUMEN

Coacervate microdroplets, a protocell model in exploring the origin of life, have gained significant attention. Clay minerals, catalysts during the origin of life, are crucial in the chemical evolution of small molecules into biopolymers. However, our understanding of the relationship between clay minerals and the formation and evolution of protocells on early Earth remains limited. In this work, the nanoclay montmorillonite nanosheet (MMT-Na) was employed to investigate its interaction with coacervate microdroplets formed by oligolysine (K10) and adenine nucleoside triphosphate (ATP). As an anionic component, MMT-Na was noted to promote the formation of coacervate microdroplets. Furthermore, the efficiency of ssDNA enrichment and the degree of ssDNA hybridization within these microdroplets were significantly improved. By combining inorganic nanoclay with organic biopolymers, our work provides an efficient way to enrich genetic biomolecules in the primitive Earth environment and builds a nanoclay-based coacervate microdroplets, shedding new light on life's origin and protocell evolution.


Asunto(s)
Células Artificiales , Bentonita , Células Artificiales/química , Bentonita/química , ADN de Cadena Simple/química , Arcilla/química , Adenosina Trifosfato/química , Nanoestructuras/química , Origen de la Vida , Hibridación de Ácido Nucleico
4.
Bull Environ Contam Toxicol ; 112(5): 68, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38722367

RESUMEN

An investigation of the impact of adding plant-based organic compost to clay soil from a Moringa oleifera farm focusing on the metal content, bioavailability, and accumulation of nutrients in M. oleifera leaves was conducted. Clay soil was mixed with 15%, 30%, 45% and 60% plant-based organic compost (by volume) in 20 cm wide, 2 L pots. Moringa oleifera plants were planted in four replicates of each treatment and control group. Results revealed that the addition of compost significantly (P < 0.05) altered the concentration of metals in the soil. Correspondingly, accumulation of nutrients in M. oleifera leaves increased with the addition of compost to the soil, except for cobalt and chromium. Trace elements had minimal bioavailability in the amended soils, and their presence in the leaves was lower than the permissible trace metal levels in food. The 30% combination had the highest concentration of calcium (45 042.5 mg/kg), magnesium (17430.0 mg/kg) and phosphorous (8802. 5 mg/kg) in M. oleifera leaves. The study concluded the addition of compost improved bioavailability of nutrients in the soil and their concentration in M. oleifera leaves. The target hazard quotients for heavy metals was less than one, indicating that M. oleifera leaf biomass harvested from soil amended with plant-based compost is safe for human consumption. These results serve as guidelines for recommended organic certification requiremets where plant-based compost is often used in the fast-growing herbal industry.


Asunto(s)
Arcilla , Compostaje , Metales Pesados , Moringa oleifera , Hojas de la Planta , Contaminantes del Suelo , Suelo , Moringa oleifera/química , Contaminantes del Suelo/análisis , Hojas de la Planta/química , Humanos , Arcilla/química , Medición de Riesgo , Suelo/química , Metales Pesados/análisis , Biomasa
5.
J Environ Manage ; 359: 121063, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38704955

RESUMEN

Due to the potential harm caused by emerging micro-pollutants to living organisms, contaminating water supplies by micro-pollutants like EDCs, pharmaceuticals, and microorganisms has become a concern in many countries. Considering both microbiological and micro-pollutant exposure risks associated with water use for agricultural/or household purposes, it is imperative to create a strategy for improving pollutant removal from treated wastewater that is both effective and affordable. Natural clay minerals efficiently remove contaminants from wastewater, though the pristine clay has less affinity to several organic pollutants. Hydrophilic polymers, viz., poly(ethylene glycol) (PEG), improve the dispersion of particles, flocculation processes, and surface properties. In this study, PEG grafted with attapulgite, thereby providing a high-specific surface-area, mesoporous materials for the adsorption of micro-pollutants like ciprofloxacin (CIP) and 17α-ethinylestradiol (EE2) at high rates. A gentle washing process regenerates the clay-polymer material several times with no performance loss, and the natural water implications show fair applicability of solid in decontaminating the CIP and EE2 in an aqueous medium. Further, greenly synthesized silver nanoparticles in situ disperse with the clay polymer efficiently remove the gram-positive and gram-negative bacterium viz., Bacillus subtilis, and Pseudomonas aeruginosa, which are commonly persistent in aquatic environments. The clay polymer outperformed a modified clay composite to eliminate microorganisms and organic micro-pollutants in significant quantities quickly. These results clearly show the importance of fibrous clay-polymer composite for water purification technologies.


Asunto(s)
Arcilla , Polímeros , Plata , Purificación del Agua , Purificación del Agua/métodos , Polímeros/química , Arcilla/química , Plata/química , Adsorción , Contaminantes Químicos del Agua/química , Aguas Residuales/química , Bacterias
6.
Harmful Algae ; 134: 102609, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38705612

RESUMEN

Modified clay compounds are used globally as a method of controlling harmful algal blooms, and their use is currently under consideration to control Karenia brevis blooms in Florida, USA. In 1400 L mesocosm tanks, chemical dynamics and lethal and sublethal impacts of MC II, a polyaluminum chloride (PAC)-modified kaolinite clay, were evaluated over 72 h on a benthic community representative of Sarasota Bay, which included blue crab (Callinectes sapidus), sea urchin (Lytechinus variegatus), and hard clam (Mercenaria campechiensis). In this experiment, MC II was dosed at 0.2 g L-1 to treat bloom-level densities of K. brevis at 1 × 106 cells L-1. Cell removal in MC II-treated tanks was 57% after 8 h and 95% after 48 h. In the water column, brevetoxin analogs BTx-1 and BTx-2 were found to be significantly higher in untreated tanks at 24 and 48 h, while in MC II-treated tanks, BTx-3 was found to be higher at 48 h and BTx-B5 was found to be higher at 24 and 48 h. In MC II floc, we found no significant differences in BTx-1 or BTx-2 between treatments for any time point, while BTx-3 was found to be significantly higher in the MC II-treated tanks at 48 and 72 h, and BTx-B5 was higher in MC II-treated tanks at 24 and 72 h. Among various chemical dynamics observed, it was notable that dissolved phosphorus was consistently significantly lower in MC II tanks after 2 h, and that turbidity in MC II tanks returned to control levels 48 h after treatment. Dissolved inorganic carbon and total seawater alkalinity were significantly reduced in MC II tanks, and partial pressure of CO2 (pCO2) was significantly higher in the MC II-only treatment after 2 h. In MC II floc, particulate phosphorus was found to be significantly higher in MC II tanks after 24 h. In animals, lethal and sublethal responses to MC II-treated K. brevis did not differ from untreated K. brevis for either of our three species at any time point, suggesting MC II treatment at this dosage has negligible impacts to these species within 72 h of exposure. These results appear promising in terms of the environmental safety of MC II as a potential bloom control option, and we recommend scaling up MC II experiments to field trials in order to gain deeper understanding of MC II performance and dynamics in natural waters.


Asunto(s)
Hidróxido de Aluminio , Dinoflagelados , Floraciones de Algas Nocivas , Toxinas Marinas , Animales , Dinoflagelados/efectos de los fármacos , Dinoflagelados/fisiología , Dinoflagelados/química , Arcilla/química , Bivalvos/fisiología , Bivalvos/efectos de los fármacos , Erizos de Mar/fisiología , Erizos de Mar/efectos de los fármacos , Florida , Braquiuros/fisiología , Braquiuros/efectos de los fármacos , Mercenaria/efectos de los fármacos , Mercenaria/fisiología , Silicatos de Aluminio/farmacología , Silicatos de Aluminio/química
7.
Skin Res Technol ; 30(4): e13672, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38591218

RESUMEN

BACKGROUND: Hyaluronic acid (HA) is a widely used active cosmetic ingredient. Its multiple skin care benefits are modulated by its molecular weight. Low molecular weight (LMW) HA can penetrate the skin, but high molecular weight (HMW) HA remains at the surface. Here, we assessed how vectorization of HMW HA with bentonite clay-achieved with an innovative technology-enhances its cosmetic and hydrating properties. MATERIALS AND METHODS: The two HA forms were applied to skin explants; their penetration and smoothing effects were monitored by Raman spectroscopy and scanning electron microscopy. The two forms were biochemically characterised by chromatography, enzyme sensitivity assays, and analysis of Zeta potential. Cosmetics benefits such as, the smoothing effect of vectorised-HA was assessed in ex vivo experiments on skin explants. A placebo-controlled clinical study was finally conducted applying treatments for 28 days to analyse the final benefits in crow's feet area. RESULTS: Raman spectroscopy analysis revealed native HMW HA to accumulate at the surface of skin explants, whereas vectorised HMW HA was detected in deeper skin layers. This innovative vectorisation process changed the zeta potential of vectorised HMW HA, being then more anionic and negative without impacting the biochemical structure of native HA. In terms of cosmetic benefits, following application of vectorised HMW HA ex vivo, the skin's surface was visibly smoother. This smoothing was clinically confirmed, with a significant reduction in fine lines. CONCLUSION: The development of innovative process vectorising HMW HA allowed HMW HA penetration in the skin. This enhanced penetration extends the clinical benefits of this iconic cosmetic ingredient.


Asunto(s)
Ácido Hialurónico , Envejecimiento de la Piel , Humanos , Ácido Hialurónico/farmacología , Ácido Hialurónico/química , Arcilla , Peso Molecular , Piel
8.
PLoS One ; 19(4): e0302150, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38625994

RESUMEN

Electroosmosis has been proposed as a technique to reduce moisture and thus increase the stability of soft clay. However, its high energy consumption and uneven reinforcement effect has limited its popularization and application in practical engineering. This paper presents the results of some electrokinetic tests performed on clayey specimens with different electrification time and anode boundary conditions. The results indicate that the timing of the formation of electroosmotic flow (EF) by the water originally contained in different soil cross sections, from the anode to the cathode, varies. The measuring soil cross section nearest the anode first reached the limiting water content of 22%±3% and electroosmosis had to be stopped. Water injection into the anode during electroosmosis enhanced further drainage of other four measuring soil cross sections until the second soil cross section from the anode reached the limiting water content of 30%±2%. Electroosmosis with water injection into the anode technique provides more uniform reinforcement, increasing EF, and environmental protection. The experimental results highlighted the relevant and expected contribution of water injection into the anode on the effectiveness of the electroosmotic treatment as a soft clay improvement technique.


Asunto(s)
Electroósmosis , Contaminantes del Suelo , Arcilla , Electroósmosis/métodos , Contaminantes del Suelo/análisis , Suelo , Agua
9.
Environ Monit Assess ; 196(5): 455, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38625667

RESUMEN

This study is to understand the fate and ecological consequences of pyroxasulfone in aridisols of Punjab, a detailed dissipation study in soil, its influence on soil enzymes, microbial count and succeeding crops was evaluated. Half-lives (DT50) increased with an increase in the application rate of pyroxasulfone. Dissipation of pyroxasulfone decreased with increase in organic matter content of soil and was slower in clay loam soil (DT50 12.50 to 24.89) followed by sandy loam (DT50 8.91 to 17.78) and loamy sand soil (DT50 6.45 to 14.89). Faster dissipation was observed under submerged conditions (DT50 2.9 to 20.99 days) than under field capacity conditions (DT50 6.45 to 24.89 days). Dissipation increased with increase in temperature with DT50 varying from 6.46 to 24.88, 4.87 to 22.89 and 2.97 to 20.99 days at 25 ± 2, 35 ± 2 and 45 ± 2 °C, respectively. Dissipation was slower under sterile conditions and about 23.87- to 33.74-fold increase in DT50 was observed under sterile conditions as compared to non-sterile conditions. The application of pyroxasulfone showed short-lived transitory effect on dehydrogenase, alkaline phosphatase and soil microbial activity while herbicide has non-significant effect on soil urease activity. PCA suggested that dehydrogenase and bacteria were most sensitive among enzymatic and microbial activities. In efficacy study, pyroxasulfone effectively controlled Phalaris minor germination, with higher efficacy in loamy sand soil (GR50 2.46 µg mL-1) as compared to clay loam soil (GR50 5.19 µg mL-1).


Asunto(s)
Isoxazoles , Arena , Suelo , Sulfonas , Arcilla , Monitoreo del Ambiente , Oxidorreductasas
10.
Environ Sci Technol ; 58(16): 7217-7227, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38588505

RESUMEN

The energy transition will have significant mineral demands and there is growing interest in recovering critical metals, including rare earth elements (REE), from secondary sources in aqueous and sedimentary environments. However, the role of clays in REE transport and deposition in these settings remains understudied. This work investigated REE adsorption to the clay minerals illite and kaolinite through pH adsorption experiments and extended X-ray absorption fine structure (EXAFS). Clay type, pH, and ionic strength (IS) affected adsorption, with decreased adsorption under acidic pH and elevated IS. Illite had a higher adsorption capacity than kaolinite; however, >95% adsorption was achieved at pH ∼7.5 regardless of IS or clay. These results were used to develop a surface complexation model with the derived binding constants used to predict REE speciation in the presence of competing sorbents. This demonstrated that clays become increasingly important as pH increases, and EXAFS modeling showed that REE can exist as both inner- and outer-sphere complexes. Together, this indicated that clays can be an important control on the transport and enrichment of REE in sedimentary systems. These findings can be applied to identify settings to target for resource extraction or to predict REE transport and fate as a contaminant.


Asunto(s)
Arcilla , Metales de Tierras Raras , Minerales , Adsorción , Metales de Tierras Raras/química , Arcilla/química , Minerales/química , Concentración de Iones de Hidrógeno , Silicatos de Aluminio/química
11.
Sci Rep ; 14(1): 8526, 2024 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-38609406

RESUMEN

Understanding the efficacy of alternative phosphorus (P) sources in tropical soils is crucial for sustainable farming, addressing resource constraints, mitigating environmental impact, improving crop productivity, and optimizing soil-specific solutions. While the topic holds great importance, current literature falls short in providing thorough, region-specific studies on the effectiveness of alternative P sources in Brazilian tropical soils for maize cultivation. Our aim was to assess the agronomic efficiency of alternative P sources concerning maize crop (Zea mays L.) attributes, including height, shoot dry weight, stem diameter, and nutrient accumulation, across five Brazilian tropical soils. In greenhouse conditions, we carried out a randomized complete block design, investigating two factors (soil type and P sources), evaluating five tropical soils with varying clay contents and three alternative sources of P, as well as a commercial source and a control group. We evaluated maize crop attributes such as height, dry weight biomass, and nutrient accumulation, P availability and agronomic efficiency. Our results showed that, although triple superphosphate (TSP) exhibited greater values than alternative P sources (precipitated phosphorus 1, precipitated phosphorus 2 and reactive phosphate) for maize crop attributes (e.g., height, stem diameter, shoot dry weight and phosphorus, nitrogen, sulfur, calcium and magnesium accumulation). For instance, PP1 source increased nutrient accumulation for phosphorus (P), nitrogen (N), and sulfur (S) by 37.05% and 75.98% (P), 34.39% and 72.07% (N), and 41.94% and 72.69% (S) in comparison to PP2 and RP, respectively. Additionally, PP1 substantially increased P availability in soils with high clay contents 15 days after planting (DAP), showing increases of 61.90%, 99.04%, and 38.09% greater than PP2, RP, and TSP. For Ca and Mg accumulation, the highest values were found in the COxisol2 soil when PP2 was applied, Ca = 44.31% and 69.48%; and Mg = 46.23 and 75.79%, greater than PP1 and RP, respectively. Finally, the highest values for relative agronomic efficiency were observed in COxisol2 when PP1 was applied. The precipitated phosphate sources (PP1 and PP2) exhibited a similar behavior to that of the commercial source (TSP), suggesting their potential use to reduce reliance on TSP fertilization, especially in soils with low clay contents. This study emphasized strategies for soil P management, aimed at assisting farmers in enhancing maize crop productivity while simultaneously addressing the effectiveness of alternative P sources of reduced costs.


Asunto(s)
Fósforo , Suelo , Agricultura , Brasil , Arcilla , Nitrógeno , Fosfatos , Azufre
12.
J Clin Neurosci ; 123: 186-193, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38599032

RESUMEN

BACKGROUND: Clay art therapy can be used as part of rehabilitation for chronic stroke patients. OBJECTIVE: The objective of this study is to examine the effect of clay therapy on hopelessness and depression levels in chronic stroke patients who receive physical therapy and compare them to patients who only receive physical therapy. METHODS: This randomized controlled study was conducted between August 1st - September 28th, 2022 in Turkiye, with 60 patients who agreed to participate in the study and met the inclusion criteria, which were chronic stroke patients who received physical therapy. The patients were divided into two groups (30 in the experimental group, 30 in the control group) with the control group receiving only their routine physical therapy and rehabilitation (5 days a week, 40 sessions in total), while the experimental group received their routine physical therapy and rehabilitation program as well as clay therapy twice a week, 60 min per session, for 8 weeks. Demographic information of all the participants was recorded, and the Beck Depression Inventory and Beck Hopelessness Scale were administered before and after treatment. RESULTS: The patients' depression posttest scores (t(58) = -11.386; p = 0.000 < 0,05), and hopelessness posttest scores (t(58) = -10.247; p = 0.000 < 0,05) differed significantly based on their groups. The control group's depression posttest scores (x¯ =25,033) and hopelessness posttest scores (x¯ =15,000) were higher than the experimental group's depression posttest scores (x¯ =9,067) and hopelessness posttest scores (x¯ =8,000). The control group's feeling about the future posttest scores (x¯ =2,967) were higher than the experimental group's posttest scores (x¯ =0,967). The control group's loss of motivation posttest scores (x¯ =6,400) were higher than the experimental group's posttest scores (x¯ =2,667). CONCLUSION: It was seen that clay therapy, in addition to physical therapy, was effective in reducing depression and hopelessness in chronic stroke patients.


Asunto(s)
Arcilla , Depresión , Esperanza , Modalidades de Fisioterapia , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Masculino , Femenino , Persona de Mediana Edad , Depresión/psicología , Depresión/etiología , Depresión/terapia , Rehabilitación de Accidente Cerebrovascular/métodos , Rehabilitación de Accidente Cerebrovascular/psicología , Accidente Cerebrovascular/psicología , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/terapia , Anciano , Enfermedad Crónica , Silicatos de Aluminio , Arteterapia/métodos , Resultado del Tratamiento
13.
Int J Pharm ; 656: 124073, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38569977

RESUMEN

Traumatic multidrug-resistant bacterial infections are the most threat to wound healing. Lower extremity wounds under diabetic conditions display a significant delay during the healing process. To overcome these challenges, the utilization of protein-based nanocomposite dressings is crucial in implementing a successful regenerative medicine approach. These dressings hold significant potential as polymer scaffolds, allowing them to mimic the properties of the extracellular matrix (ECM). So, the objective of this study was to develop a nanocomposite film using dialdehyde-xanthan gum/soy protein isolate incorporated with propolis (PP) and halloysite nanotubes (HNTs) (DXG-SPI/PP/HNTs). In this protein-polysaccharide hybrid system, the self-healing capability was demonstrated through Schiff bonds, providing a favorable environment for cell encapsulation in the field of tissue engineering. To improve the properties of the DXG-SPI film, the incorporation of polyphenols found in PP, particularly flavonoids, is proposed. The synthesized films were subjected to investigations regarding degradation, degree of swelling, and mechanical characteristics. Additionally, halloysite nanotubes (HNTs) were introduced into the DXG-SPI/PP nanocomposite films as a reinforcing filler with varying concentrations of 3 %, 5 %, and 7 % by weight. The scanning electron microscope (SEM) analysis confirmed the proper embedding and dispersion of HNTs onto the DXG-SPI/PP nanocomposite films, leading to functional interfacial interactions. The structure and crystallinity of the synthesized nanocomposite films were characterized using Fourier Transform Infrared Spectrometry (FTIR) and X-ray diffraction (XRD), respectively. Moreover, the developed DXG-SPI/PP/HNTs nanocomposite films significantly improved cell growth of NIH-3T3 fibroblast cells in the presence of PP and HNTs, indicating their cytocompatibility. The antibacterial activity of the nanocomposite was evaluated against Escherichia coli (E. Coli) and Staphylococcus aureus (S. Aureus), which are commonly associated with wound infections. Overall, our findings suggest that the synthesis of DXG-SPI/PP/HNTs nanocomposite scaffolds holds great promise as a clinically relevant biomaterial and exhibits strong potential for numerous challenging biomedical applications.


Asunto(s)
Antibacterianos , Antioxidantes , Arcilla , Nanocompuestos , Nanotubos , Polisacáridos Bacterianos , Própolis , Proteínas de Soja , Cicatrización de Heridas , Antibacterianos/química , Antibacterianos/farmacología , Antibacterianos/administración & dosificación , Nanotubos/química , Arcilla/química , Cicatrización de Heridas/efectos de los fármacos , Animales , Própolis/química , Própolis/farmacología , Própolis/administración & dosificación , Polisacáridos Bacterianos/química , Ratones , Proteínas de Soja/química , Antioxidantes/química , Antioxidantes/farmacología , Antioxidantes/administración & dosificación , Nanocompuestos/química , Staphylococcus aureus/efectos de los fármacos , Escherichia coli/efectos de los fármacos
14.
Environ Sci Pollut Res Int ; 31(20): 29357-29373, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38573574

RESUMEN

In this study, Tunisian raw clay (RC) was utilized as a cheap source of silicium and aluminum for the preparation of faujasite zeolite (FAUsyn) using the alkaline fusion technique. The zeolite's structural analysis was carried out using the XRD, nitrogen adsorption-desorption, and SEM-EDX techniques. The data collected demonstrate that the produced zeolite only included one homogeneous faujasite phase. Textural analysis shows that the FAUsyn prepared from RC has a hierarchical porosity (micro-, meso-, and macropores). The total porosity was found to be 0.33 cm3/g as well as the BET area was equal to 360 m2/g. Adsorption experiments for propene capture were performed using the FAUsyn as adsorbent material. The performance of the column was examined in relation to various parameter impacts, including flow rate (50, 100, and 150 mL/min), input concentration (4, 8, and 12 mg/L), and bed depth (10, 14, and 18 cm). Finally, experimental and theoretical studies were investigated to predict adsorption capacities and kinetics parameters. To clarify and estimate column inputs, a model that incorporates axial dispersion, Langmuir equation, and migration within the adsorbent's pore was improved. COMSOL Multiphysics software was used to execute the model and resolve it computationally. The results of the experiments and the expected breakthrough curves were very well agreed. Modeling obtained results can be extrapolated to industrial level.


Asunto(s)
Arcilla , Zeolitas , Zeolitas/química , Adsorción , Arcilla/química , Túnez , Cinética , Porosidad
15.
Environ Sci Pollut Res Int ; 31(20): 29719-29729, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38584232

RESUMEN

The application of bentonite (Bt) as an adsorbent for heavy metals has been limited due to its hydrophobicity and insufficient surface area. Herein, we present cellulose nanocrystal (CNC) modified Bt composite (CNC@Bt) with enhanced efficiency for Cr(VI) removal. CNC@Bt exhibited an increased specific surface area and a porous structure, while maintaining the original crystal structure of Bt. This was achieved through a synergistic function of ion exchange, hydrogen bonding, electrostatic interactions, and steric hindrance. The adsorption of Cr(VI) by CNC@Bt followed the pseudo-second-order kinetic and Langmuir isotherm adsorption model. Moreover, the process was endothermic and spontaneous. At an initial Cr(VI) concentration of 20 mg/L and pH = 4.0, 10 g/L CNC@Bt achieved a removal rate of 92.7%, and the adsorption capacity was 1.85 mg/g, significantly higher than bare Bt (37.9% and 0.76 mg/g). The removal efficiency remained consistently above 80% over a wide pH range, indicating the potential practical applicability of CNC@Bt. With its fast adsorption rate, pH adaptability, and stable performance, CNC@Bt presents promising prospects for the rapid treatment of Cr-contaminated wastewater.


Asunto(s)
Celulosa , Cromo , Nanopartículas , Contaminantes Químicos del Agua , Celulosa/química , Nanopartículas/química , Adsorción , Cromo/química , Contaminantes Químicos del Agua/química , Cinética , Arcilla/química , Bentonita/química , Concentración de Iones de Hidrógeno
16.
Biomed Mater ; 19(3)2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38636501

RESUMEN

Palygorskite (Pal) is a naturally available one-dimensional clay mineral, featuring rod-shaped morphology, nanoporous structure, permanent negative charges as well as abundant surface hydroxyl groups, exhibiting promising potential as a natural hemostatic material. In this study, the hemostatic performance and mechanisms of Pal were systematically investigated based on the structural regulate induced by oxalic acid (OA) gradient leaching from perspectives of structure, surface attributes and ion release.In vitroandin vivohemostasis evaluation showed that Pal with OA leaching for 1 h exhibited a superior blood procoagulant effect compared with the raw Pal as well as the others leached for prolonging time. This phenomenon might be ascribed to the synergistic effect of the intact nanorod-like morphology, the increase in the surface negative charge, the release of metal ions (Fe3+and Mg2+), and the improved blood affinity, which promoted the intrinsic coagulation pathway, the fibrinogenesis and the adhesion of blood cells, thereby accelerating the formation of robust blood clots. This work is expected to provide experimental and theoretical basis for the construction of hemostatic biomaterials based on clay minerals.


Asunto(s)
Coagulación Sanguínea , Hemostáticos , Compuestos de Magnesio , Ácido Oxálico , Compuestos de Silicona , Compuestos de Magnesio/química , Ácido Oxálico/química , Animales , Compuestos de Silicona/química , Coagulación Sanguínea/efectos de los fármacos , Hemostáticos/química , Hemostáticos/farmacología , Materiales Biocompatibles/química , Hemostasis/efectos de los fármacos , Ensayo de Materiales , Humanos , Propiedades de Superficie , Arcilla/química , Magnesio/química , Ratas
17.
Environ Pollut ; 349: 123903, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38599272

RESUMEN

To investigate watershed remediation within a Total Maximum Daily Load program, this study examined the field-scale filtration performance of two specialty absorbents. The goal was to simultaneously remove nutrients and biological pollutants along Canal 23 (C-23) in the St. Lucie River Basin, Florida. The filtration system installed in the C-23 river corridor was equipped with either clay-perlite with sand sorption media (CPS) or zero-valent iron and perlite green environmental media (ZIPGEM). Both media were formulated with varying combinations of sand, clay, perlite, and/or recycled iron based on distinct recipes. In comparison with CPS, ZIPGEM exhibited higher average removal percentages for nutrients. Findings indicated that ZIPGEM could remove total nitrogen up to 49.3%, total Kjeldahl nitrogen up to 67.1%, dissolved organic nitrogen (DON) up to 72.9%, total phosphorus up to 79.6%, and orthophosphate up to 73.2%. Both ZIPGEM and CPS demonstrated similar efficiency in eliminating biological pollutants, such as E. coli (both media exhibiting an 80% removal percentage) and chlorophyll a (both media achieving approximately 95% removal). Seasonality effects were also evident in nutrient removal efficiencies, particularly in the case of ammonia nitrogen; the negative removal efficiency of ammonia nitrogen from the fifth sampling event could be attributed to processes such as photochemical ammonification, microbial transformation, and mineralization of DON in wet seasons. Overall, ZIPGEM demonstrated a more stable nutrient removal efficiency than CPS in the phase of seasonal changes.


Asunto(s)
Restauración y Remediación Ambiental , Filtración , Nitrógeno , Fósforo , Dióxido de Silicio , Contaminantes Químicos del Agua , Filtración/métodos , Contaminantes Químicos del Agua/análisis , Restauración y Remediación Ambiental/métodos , Restauración y Remediación Ambiental/instrumentación , Florida , Purificación del Agua/métodos , Ríos/química , Óxido de Aluminio/química , Escherichia coli , Clorofila A , Arcilla/química , Hierro/química
18.
Chemosphere ; 358: 142134, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38677609

RESUMEN

Soil cracking can significantly alter the water and nutrient migration pathways in the soil, influencing plant growth and development. While biochar usage has effectively addressed soil cracking, the feasibility of using less energy-intensive hydrochars in desiccating soils remains unexplored. This study investigates the impact of wood and peanut shell hydrochars on the desiccation cracking characteristics of clayey soil. A series of controlled environmental laboratory incubations with regular imaging was conducted to determine crack development's dynamic in unamended and hydrochar-amended soils. The results reveal that the addition of wood hydrochar at 2% and 4% dosage reduced the crack intensity factor (CIF) by 22% and 43%, respectively, compared to the unamended control soil. Similarly, the inclusion of peanut shell hydrochar at 2% and 4% lowered the CIF by 22% and 51%, respectively. The presence of hydrophilic groups on the surface of hydrochars, such as O-H, CH, and C-O-C, enhanced the water retention capacity, as confirmed by Fourier-transform infrared analysis. The CIF decrease is attributed to mitigated water evaporation rates, enabled by enhanced water retention within the hydrochar pore spaces. These findings are supported by scanning electron microscopy analyses of the hydrochar morphology. Despite CIF reduction with hydrochar incorporation, the crack length density (CLD) increased across all hydrochar-amended series. In contrast to unamended soil which exhibited pronounced widening of large cracks and extensive inter-pore voids, the incorporation of hydrochar resulted in higher CLD due to the formation of finer interconnecting crack meshes. Consequently, the unamended control soil suffered greater water loss due to heightened evaporation rates. This study sheds new light on the potential of hydrochars in addressing desiccation-induced soil cracking and its implications for water conservation.


Asunto(s)
Arachis , Arcilla , Desecación , Suelo , Madera , Madera/química , Suelo/química , Arcilla/química , Agua/química , Carbón Orgánico/química
19.
Int J Biol Macromol ; 267(Pt 2): 131375, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38604424

RESUMEN

Compostable zein-polycaprolactone (PZ) electrospun nanofiber integrated with different concentrations of Aster yomena extract loaded halloysite nanotubes (A. yomena-HNT) as bioactive nanofibrous food packaging is reported. SEM micrographs reveal heterogeneous nanofibers. A. yomena extract used in the study showed weak antioxidant activity with AAI and TEAC values of 0.229 and 0.346. In vitro, release profile over 7 days of A. yomena indicates a controlled, sustained, and prolonged release. The prepared nanofibers were effective against both gram-positive and gram-negative bacteria. The prepared composite nanofibers were rendered biocompatible and nontoxic when subjected to WST-1 and LDH assay after incubating with NIH 3T3 mouse fibroblast cell line. PZ-15 nanofiber packaging showed the best postharvest quality preservation in Black mulberry fruits after 4 days of storage at 25 °C and 85 % Rh. Moreover, the in vitro decomposition test reveals that the fabricated nanofibers decompose in the soil and do not pose as a threat to the environment.


Asunto(s)
Arcilla , Embalaje de Alimentos , Nanofibras , Nanotubos , Extractos Vegetales , Poliésteres , Zeína , Nanofibras/química , Poliésteres/química , Zeína/química , Ratones , Animales , Arcilla/química , Embalaje de Alimentos/métodos , Nanotubos/química , Células 3T3 NIH , Extractos Vegetales/química , Extractos Vegetales/farmacología , Antioxidantes/farmacología , Antioxidantes/química , Antibacterianos/farmacología , Antibacterianos/química
20.
Int J Biol Macromol ; 267(Pt 2): 131651, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38636746

RESUMEN

The plastics derived from fossil fuels for food packaging results in serious environmental problems. Developing environment-friendly materials for food packaging is urgent and essential. In this study, polylactic acid (PLA) composite nanofibers membranes were prepared with good biocompatibility and antibacterial property. Cu2+ loaded in the natural halloysite nanotubes (HNTs) was used for the antibacterial agent. Cu2+ was loaded in the HNTs and was confirmed by the X-ray photoelectron spectroscopy (XPS). PLA nanofibers with different HNTs-Cu content were continuous nanofibers with the nanoscale range. HNTs-Cu entered into the nanofiber successfully. Thermal analysis results showed composite nanofibers had good thermal stability. Composite nanofiber membranes had the good hydrophobic property. HNTs-Cu improved the mechanical property of composite nanofibers than pure PLA nanofibers. Tensile strength and elasticity modulus of composite nanofibers with 4 % HNTs-Cu content were the most outstanding. L929 cells were cultured on the nanofiber membranes for biocompatibility evaluation. Cell viability of nanofiber membranes was above the 90 %. Cell live/dead staining results showed L929 cells was seldom dead on the nanofiber membranes. PLA/HNTs-Cu nanofiber membranes exhibited excellent antibacterial effects on S. aureus and E. coli. The inhibitory rates against S. aureus and E. coli were 98.31 % and 97.80 % respectively. The fresh-keeping effects of nanofiber membranes were evaluated by the strawberry preservation. Strawberries covered by nanofiber membranes exhibited better appearance, lower weight loss and higher firmness than control, PLA and PLA/HNTs groups. It promised that PLA/HNTs-Cu composite nanofiber membranes have the significant potential application for active food packaging.


Asunto(s)
Antibacterianos , Arcilla , Cobre , Embalaje de Alimentos , Nanofibras , Nanotubos , Poliésteres , Staphylococcus aureus , Cobre/química , Cobre/farmacología , Nanofibras/química , Poliésteres/química , Nanotubos/química , Embalaje de Alimentos/métodos , Arcilla/química , Antibacterianos/farmacología , Antibacterianos/química , Staphylococcus aureus/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Ratones , Membranas Artificiales , Animales , Línea Celular , Resistencia a la Tracción , Supervivencia Celular/efectos de los fármacos
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