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1.
Ultrason Sonochem ; 111: 107096, 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39383789

RESUMEN

Bacterial infections pose considerable health risks, emphasising the critical need for effective and biocompatible antibacterial drugs. Considerably, we developed an efficient antimicrobial system incorporating the combined potential of high-frequency ultrasound and antimicrobial drugs against bacterial infections. A ZnO-kaolinite (Kaol) composite with antibacterial properties was synthesised by growing ZnO on the Kaol nano-clay surface using the co-precipitation method. High-frequency ultrasound efficiently promotes the release of Zn2+, which enhances the antibacterial properties. Furthermore, in-depth in vitro antibacterial studies and bacterial live/dead staining experiments validate the exceptionally high antibacterial performance of the composite. Therefore, owing to the synergistic effects of high-frequency ultrasound and antibacterial properties, the as-prepared novel antibacterial composite is a promising potential substitute for conventional antibacterial agents.

2.
Artículo en Inglés | MEDLINE | ID: mdl-39353462

RESUMEN

The importance of real-time dose evaluation has increased for recent advanced radiotherapy. However, conventional methods for real-time dosimetry using gel dosimeters face challenges owing to the delayed dose response caused by the slow completion of radiation-induced chemical reactions. In this study, a novel technique called photoluminescence-detected pulse radiolysis (PLPR) was developed, and its potential to allow real-time dose measurements using nano-clay radio-fluorogenic gel (NC-RFG) dosimeters was investigated. PLPR is a time-resolved observation method, and enables time-resolved fluorescence measurement. NC-RFG dosimeters were prepared, typically consisting of 100 µM dihydrorhodamine 123 (DHR123) and 2.0 wt.% nano-clay, along with catalytic and dissolving additives. We successfully achieved time-resolved observation of the increase in fluorescence intensity upon irradiation of the dosimeter. Dose evaluation was possible at 1 s after irradiation. The dose-rate effect was not observed for the deoxygenated dosimeter, but was observed for the aerated dosimeter. Besides the dose-rate effect, linear dose responses were obtained for both conditions. Furthermore, we made a novel observation of a decay in the fluorescence intensity over time in the early stages which named fluorescence secondary loss (FSL) and elucidated the conditions under which this phenomenon occurs.

3.
Small ; : e2402648, 2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-39375963

RESUMEN

Metal ions show tremendous promise for tumor therapy due to their critical roles in many important catalytic circulations and immune processes. However, the valence state variability and systemic side-effects of metal ions cause ineffective ion enrichment in tumor cells, which limit their further application. Here, a Mn3+ ion delivery system (Mn-HNT) is constructed based on halloysite nanotubes (HNT) via an ion-engineered strategy. Due to the stabilizing effect of HNT on Mn3+ ions, Mn-HNT not only maintained the valence state of Mn3+ ions, but also presented strong catalase (CAT)- and glutathione oxidase (GSHOx)-like catalytic activity to catalyze O2 generation and GSH consumption to relieve the inhibition of tumor microenvironment on photodynamic therapy (PDT). After further coordination with the photosensitizer porphyrin (TCPP), obtained TCPP-Mn-HNT not only inherited the catalytic properties of Mn-HNT to produce oxygen and consume GSH, but acted as photosensitizer for ROS accumulation to effectively destroy tumor cells. Moreover, TCPP-Mn-HNT can promote the maturation of dendritic cells (≈2.8 times), and present the tumor antigen triggered by PDT to T cells to strengthen high-efficient tumor therapy. The study provides new opportunities for designing metal ion delivery system with versatile biofunctions and offers a paradigm of synergistic metal-ion-mediated tumor therapy.

4.
ACS Appl Bio Mater ; 2024 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-39415452

RESUMEN

Biocompatible and biodegradable nerve growth conduits (NGCs) provide a promising alternative to conventional nerve grafting for peripheral nerve regeneration. Incorporating nanoclay (NC) has been shown to increase the hydrophilicity and flexibility of polymeric scaffolds. In the present study, poly caprolactone-alginate (PCL-ALG) conduits with varying percentages of NC (0.1%, 0.2%, and 0.5%) were fabricated using the electrospinning technique. The conduit containing 0.5% NC showed a greater increase in elongation (33%) and porosity, reaching 95% with the lowest contact angle (10°). For in vitro, human olfactory ectomesenchymal stem cells (OE-MSCs) were used as a favorable choice for neuronal differentiation owing to the origin from the neural crest. The viability and proliferation of OE-MSCs were maintained after 5 days on scaffolds with 0.5% NC, as confirmed by the MTT assay, cell adhesion analysis, and live/dead staining. Furthermore, the impact of 0.5% PCL-ALG-NC on the paracrine activity of OE-MSCs was studied for a period of 7 days. Our results indicated that human OE-MSCs, when cocultured with PC12 cells on NGC, have the capability to release nerve growth factor levels of up to 1392.83 pg/mL. In summary, the electrospun PCL-ALG conduit containing an optimal NC dosage (0.5%) and seeded with human OE-MSCs shows promising outcomes as NGC scaffold for peripheral nerve regeneration.

5.
Int J Biol Macromol ; 279(Pt 4): 135391, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39245111

RESUMEN

A special nano-filter made of cellulose acetate (CA) was developed, including a 3D hierarchically porous structure. The nano-filter utilized nano-clay (hydrophilic bentonite (NCB)), comprising 0.5-1.5 % of its weight. The objective of this study was to evaluate the adsorption properties of four carcinogenic polyaromatic hydrocarbons (benz[α] anthracene (BαA), chrysene (CHR), benzo[ß]fluoranthene (BßF), and benzo[α] pyrene (BαP)) during the rice smoking process. The evaluation of the nano-filter encompassed an analysis of its mechanical attributes, surface qualities, morphology, and adsorption efficacy. The experimental results demonstrated that adding NCB to the nano-filter composition of CA led to substantial improvements in tensile strength, elongation at break, and maximum load stress values compared to the control group. The nano-filter displayed a uniform and homogeneously distributed arrangement of nanoparticles. The GC-MS analysis demonstrated that the enhanced nano-filter, comprising nano-clay particles, successfully absorbed the polycyclic aromatic hydrocarbons (PAHs) over a 21-day rice smoking period. The performance, removal efficiency and porosity during repetitive filtering and cleaning cycles in the rice samples at different smoking times were approved reusability of CA-NCB filter. It is recommended to explore the application of hybrid CA nano-filter s, namely those containing NCB, as a cutting-edge filtration technique for smoked food products.


Asunto(s)
Celulosa , Nanofibras , Nanofibras/química , Celulosa/química , Celulosa/análogos & derivados , Porosidad , Arcilla/química , Filtros de Aire , Adsorción , Oryza/química , Hidrocarburos Policíclicos Aromáticos/química , Hidrocarburos Policíclicos Aromáticos/aislamiento & purificación , Resistencia a la Tracción , Filtración/métodos , Bentonita/química
6.
Int J Biol Macromol ; 279(Pt 4): 135363, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39260628

RESUMEN

The worldwide challenge of eliminating pharmaceutical contaminants requires immediate attention. Developing bio-based catalysts that are eco-friendly, reusable, and high-performance, employing starch (ST) and montmorillonite (MMT) as support, holds tremendous promise as a novel biocatalyst for pharmaceutical waste removal. In this study, a montmorillonite/α-Fe2O3/starch (MMT/α-Fe2O3/ST) bio-nanocomposite photocatalyst was successfully synthesized and used for acetaminophen (ACT) degradation under UVA-LED irradiation. The influence of operational factors, such as catalyst, ACT concentrations, and solution pH, on photocatalytic activity was examined in detail; catalyst: 0.75 g/L, pH: 7.1, leading to total ACT (10 mg/L) removal in ∼80 min. MMT/α-Fe2O3/ST showed excellent durability due to negligible Fe leaching. After four successive degradation cycles, ACT and TOC elimination efficiencies remained over 91 and 42.7 %. Compared to other anions studied, carbonate ions suppressed the most ACT degradation. Based on the radical scavenger experiments, hydroxyl and superoxide radicals and holes were involved in the MMT/α-Fe2O3/ST system. LC-MS results were used to propose ACT degradation pathways. This work illuminated the significance of biocatalysts in removing emerging pollutants from wastewater.


Asunto(s)
Acetaminofén , Bentonita , Compuestos Férricos , Nanocompuestos , Almidón , Bentonita/química , Almidón/química , Acetaminofén/química , Nanocompuestos/química , Catálisis , Compuestos Férricos/química , Contaminantes Químicos del Agua/química , Concentración de Iones de Hidrógeno , Fotólisis , Purificación del Agua/métodos , Aguas Residuales/química
7.
Nanomaterials (Basel) ; 14(17)2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39269065

RESUMEN

An understanding of the mechanical behavior of polymeric materials is crucial for making advancements in the applications and efficiency of nanocomposites, and encompasses their service life, load resistance, and overall reliability. The present study focused on the prediction of the mechanical behavior of biopolymeric nanocomposites with nano-clays as the nanoadditives, using a new modeling and simulation method based on Comsol Multiphysics software 6.1. This modeling considered the complex case of flake-shaped nano-clay additives that could form aggregates along the polymeric matrix, varying the nanoadditive thickness, and consequently affecting the resulting mechanical properties of the polymeric nanocomposite. The polymeric matrix investigated was biopolyamide 11 (BIOPA11). Several BIOPA11 samples reinforced with three different contents of nano-clays (0, 3, and 10 wt%), and with three different nano-clay dispersion grades (employing three different extrusion screw configurations) were obtained by the compounding extrusion process. The mechanical behavior of these samples was studied by the experimental tensile test. The experimental results indicate an enhancement of Young's modulus as the nano-clay content was increased from 0 to 10 wt% for the same dispersion grades. In addition, the Young's modulus value increased when the dispersion rate of the nano-clays was improved, showing the highest increase of around 93% for the nanocomposite with 10 wt% nano-clay. A comparison of the modeled mechanical properties and the experimental measurements values was performed to validate the modeling results. The simulated results fit well with the experimental values of Young's modulus.

8.
Chemosphere ; 364: 143309, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39265733

RESUMEN

Herein, coupling of noble metal-free plasmonic copper nanoparticles with tungsten suboxide and supporting on zeolite nanoclay (Cu/WO3-x@ZNC) composite will be introduced for bi-functional photocatalytic ciprofloxacin (CIP) degradation and water photothermal evaporation under visible/infrared (Vis/IR) exposure. Reduced band-gap of WO3-x via oxygen vacancies creation and localized surface plasmon resonance (LSPR) formation by Cu nanoparticles contributed significantly the extension and intensification of composite's photo-absorption range. Furthermore, small mesoporous structure of ZNC enhanced CIP adsorption and charge carriers separation where the reported photocatalytic efficiencies were 88.3 and 81.7% upon IR and Vis light exposure respectively. It was evidenced that plasmonic hot electrons (e-.s) and hydroxyl radicals (OH•-) performed the basic functions of the photocatalytic process. At the other side, oxygen vacancies existence, plasmonic effect, and confining thermal characteristics of WO3-x, Cu, and ZNC correspondingly induced water photothermal evaporation with efficiencies up to 97.5 and 72.8% under IR and Vis illumination respectively. This work introduces synthesis of a novel bi-functional photocatalytic-photothermal composite by metal sub-oxide and non-noble metal plasmonic coupling and supporting on naturally-derived carrier for water restoration under broad spectral exposure.


Asunto(s)
Ciprofloxacina , Cobre , Tungsteno , Ciprofloxacina/química , Cobre/química , Tungsteno/química , Catálisis , Contaminantes Químicos del Agua/química , Óxidos/química , Nanopartículas del Metal/química , Agua/química , Zeolitas/química , Rayos Infrarrojos , Fotólisis , Procesos Fotoquímicos , Resonancia por Plasmón de Superficie , Adsorción
9.
Int J Biol Macromol ; 280(Pt 2): 135591, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39304055

RESUMEN

The objective of this study is to create high-performance nano biocomposites by utilizing unsaturated polyester resin (PE) reinforced with pre-treated short (2 cm) lengthened sunn hemp (SH) fibers and by incorporating 5 % nanoclay (hydrophilic bentonite) through the compression molding technique. The addition of 5 % nanoclay to the biocomposite significantly increased the flexural strength by approximately 165 % for H2O2-treated SH fiber and 148 % for KMnO4-treated SH fiber, when compared to untreated fibers. This enhancement was achieved through phase separation, intercalation, and exfoliation between the SH fibers, polyester resin (PE), and 5 % nanoclay. In particular, the H2O2-treated SH fiber nanobiocomposite exhibited a 43 % higher flexural strength compared to its corresponding biocomposite. The incorporation of nanoclay significantly decreased the water absorption of the bio-composites from 11.86 % in the untreated samples to a minimum of 2.76 % in the H2O2-treated SH/PE nanobiocomposite. The study suggests that short SH fiber/PE/nanoclay nanobiocomposites could be used as effective alternatives to synthetic composites in various applications, including the aerospace industry, household products, and automotive interior components such as side panels, seat frames, and central consoles. Additionally, they could be utilized in exterior parts like door panels and dashboards.

10.
Sci Total Environ ; 951: 175641, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-39168336

RESUMEN

The extensive use of the antibiotic oxytetracycline (OTC) has led to considerable environmental contamination and other negative impacts, prompting an urgent need for a green, effective, and innovative OTC adsorption material. In this study, diatom-allophane bio-nanocomposites were synthesized using a simple and eco-friendly method, yielding a homogeneous coating of allophane nanoparticles on diatom surfaces. The resultant bio-nanocomposites were found to have hierarchically porous structures and abundant active sites derived from successful allophane loading and dispersion on diatom surfaces. The OTC adsorption capacity of this novel adsorbent is remarkable (219.112 mg·g-1), surpassing the capacities of raw allophane and diatoms by >5 and 10 times, respectively. Mechanistically, OTC adsorption by the bio-nanocomposites was found to be driven primarily by chemisorption through a process involving complexation between the amide and amino groups on OTC and the aluminum hydroxyl and carboxyl groups on the adsorbent surface. Electrostatic interactions and hydrogen bonding also contribute significantly to OTC capture. Furthermore, the diatom-allophane bio-nanocomposites exhibit excellent performance over a wide pH range (4-7), in the presence of various cations (Na+, K+, Ca2+, Mg2+) and anions (Cl-, NO3-, SO42-), and in real water bodies. These findings demonstrate the potential of the diatom-allophane bio-nanocomposite as a green, efficient, and promising biological-mineral adsorbent for environmental remediation, leveraging the combined utilization of biological and mineral resources.


Asunto(s)
Diatomeas , Nanocompuestos , Oxitetraciclina , Contaminantes Químicos del Agua , Oxitetraciclina/química , Adsorción , Contaminantes Químicos del Agua/química , Nanocompuestos/química , Antibacterianos/química , Tecnología Química Verde
11.
Int J Biol Macromol ; 278(Pt 3): 134592, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39122069

RESUMEN

Developing an effective and user-friendly hemostatic agent is highly desired in the treatment of hemorrhage. Inspired by the natural nanostructure and abundant hydroxyl groups of cellulose and clay minerals, we designed an aerogel (HNTs/TOCNs) composed of halloysite nanotubes (HNTs) and TEMPO-oxidized cellulose nanofibers (TOCNs) with a hierarchical porous structure for the treatment of bleeding, using a simple and environmentally friendly self-assembly method. TOCNs formed a three-dimensional porous scaffold with excellent water-holding capacity. The incorporation of HNTs enhanced the hemostatic efficiency and mechanical properties of the 3D framework. The large interlayer spaces and wide channels within the HNTs/TOCNs aerogel provided rapid passage for blood, facilitating blood concentration and offering ample room for interactions between the HNTs/TOCNs aerogel and platelets, erythrocytes, and coagulation factors, thereby promoting hemostasis. Benefiting from the natural hemostatic properties and well-designed structure, the HNTs/TOCNs aerogel displayed excellent hemostatic performance both in vitro and in vivo. Notably, the hemostatic time of HNTs/TOCNs-2 was only 74 ± 8 s, which is approximately 50 % shorter than the blank control (151 ± 20 s) in liver femoral artery injury model. This design of an HNTs/TOCNs aerogel presents a unique opportunity to enhance hemostatic efficacy by synergizing the advantages of natural materials.


Asunto(s)
Celulosa , Arcilla , Hemostasis , Nanofibras , Nanofibras/química , Porosidad , Animales , Hemostasis/efectos de los fármacos , Arcilla/química , Celulosa/química , Geles/química , Hemostáticos/química , Hemostáticos/farmacología , Ratas , Hemorragia/tratamiento farmacológico , Masculino , Nanotubos/química , Óxidos N-Cíclicos/química , Ratones
12.
Iran J Vet Res ; 25(1): 16-24, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39156793

RESUMEN

Background: Incorporation of bentonite into the diets of ruminants can be helpful to maximize their performance. Modifying the structure of bentonite to nano and nanocomposite has improved their chemical stability and physicochemical properties, enhancing adsorption, absorption, and cation exchange capacity. Aims: This study aimed to assess the effect of magnetic bentonite nanocomposite (MBNC) on in vivo and in vitro fermentation process patterns, nutrient digestibility, and growth performance of Baluchi male lambs. Methods: Effects of control (basal diet), natural bentonite (NB) (10 g/kg dry matter (DM)), processed bentonite (PB) (5 and 10 g/kg DM basal diet), and MBNC (5 and 10 g/kg DM basal diet) on gas production (GP), and the fermentation process were determined using in vitro GP technique. For the in vivo experiment, 20 Baluchi male lambs were used with 4 experimental treatments: control, NB (5 g/kg DM), PB (5 g/kg DM), and MBNC (5 g/kg DM) and 5 replications in a completely randomized design for 60 consecutive days. Results: The potential for GP and its fractional rates were significantly decreased and increased in MBNC, respectively (P<0.01). The lowest cumulative GP, and CH4 yield were observed in MBNC (P<0.05). In vitro, DM and organic matter (OM) digestibility and all fermentation parameters increased with the addition of two levels of MBNC to the culture medium (P<0.01). Except for feed conversion ratio (FCR), other growth performance parameters increased with the addition of MBNC to the diet (P<0.01). The ruminal pH, total volatile fatty acids (TVFA), acetate, and propionate significantly increased when MBNC incorporated to the diet (P<0.01). The NH3-N (P<0.001) was significantly decreased in MBNC. The bentonite supplementation decreased acetate to propionate (P=0.001) compared to the control. Conclusion: Adding MBNC at the 5 g/kg diet DM level can be used as a useful supplement to optimize rumen fermentation pattern, reduce methane production, and increase lamb performance.

13.
J Biomed Mater Res B Appl Biomater ; 112(9): e35477, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39213159

RESUMEN

Our laboratory recently developed a new class of high surface area, honeycomb Nanoclay Microsphere Framework absorbents (NMFs) that prompt rapid hemostasis. In the present work, we propose a novel approach to develop antibacterial Topical Hemostatic Agents (THAs) by anchoring silver nanoparticles (AgNPs) onto NMFs. This combination was obtained by a chemical co-reduction approach, followed by freeze-processing, and was shown to ensure stability and on-site delivery of AgNPs, without altering the hemostatic properties of NMFs. Silver-loaded NMFs showed no change in their unique architecture and led to a 55% increase in clot strength, compared to standard control plasma or commercially available THA, and a significant decrease in mean fibrin fiber diameter. Silver nanoparticles were successfully released when solubilized and prevented the growth of both Pseudomonas aeruginosa and Staphylococcus aureus at concentrations of 22 and 30 ppm of silver released, respectively. Overall, cell mortality was between 9.1 ± 5.1% and 6.3 ± 3.2%, depending on AgNP concentration, confirming a low cytotoxicity. Silver-loaded nanoclay microsphere frameworks appear to constitute promising candidates as topical hemostatic agents for secondary management of hemostasis when infection control is needed.


Asunto(s)
Antibacterianos , Arcilla , Hemostáticos , Nanopartículas del Metal , Pseudomonas aeruginosa , Plata , Staphylococcus aureus , Antibacterianos/farmacología , Antibacterianos/química , Plata/química , Plata/farmacología , Hemostáticos/farmacología , Hemostáticos/química , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Pseudomonas aeruginosa/efectos de los fármacos , Nanopartículas del Metal/química , Arcilla/química , Humanos , Hemostasis/efectos de los fármacos
14.
Gels ; 10(8)2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39195042

RESUMEN

Nanoclay-composite hydrogels represent a promising avenue for advancing bone tissue engineering. Traditional hydrogels face challenges in providing mechanical strength, biocompatibility, and bioactivity necessary for successful bone regeneration. The incorporation of nanoclay into hydrogel matrices offers a potential unique solution to these challenges. This review provides a comprehensive overview of the fabrication, physico-chemical/biological performance, and applications of nanoclay-composite hydrogels in bone tissue engineering. Various fabrication techniques, including in situ polymerization, physical blending, and 3D printing, are discussed. In vitro and in vivo studies evaluating biocompatibility and bioactivity have demonstrated the potential of these hydrogels for promoting cell adhesion, proliferation, and differentiation. Their applications in bone defect repair, osteochondral tissue engineering and drug delivery are also explored. Despite their potential in bone tissue engineering, nanoclay-composite hydrogels face challenges such as optimal dispersion, scalability, biocompatibility, long-term stability, regulatory approval, and integration with emerging technologies to achieve clinical application. Future research directions need to focus on refining fabrication techniques, enhancing understanding of biological interactions, and advancing towards clinical translation and commercialization. Overall, nanoclay-composite hydrogels offer exciting opportunities for improving bone regeneration strategies.

15.
Sci Rep ; 14(1): 19687, 2024 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-39181917

RESUMEN

This study investigated the adsorption of Oxytetracycline (OTC) from pharmaceutical wastewater using a kappa carrageenan based hydrogel (KPB). The aim of the present study was to explore the potential of KPB for long-term pharmaceutical wastewater treatment. A sustainable adsorbent was developed to address oxytetracycline (OTC) contamination. The hydrogel's structural and adsorption characteristics were examined using various techniques like Scanning Electron Microscope (SEM), Fourier Transform Infrared (FTIR), X-ray powder diffraction (XRD), and kinetic models. The results revealed considerable changes in the vibrational modes and adsorption bands of the hydrogel, suggesting the effective functionalization of Bentonite nano-clay. Kappa carrageenan based hydrogel achieved the maximum removal (98.5%) of OTC at concerntration of 40 mg/L, pH 8, cotact time of 140 min and adsorbent dose of 0.1 g (KPB-3). Adsorption of OTC increased up to 99% with increasing initial concentrations. The study achieved 95% adsorption capacity for OTC using a KPB film at a concentration of 20 mg/L and a 0.1 g adsorbent dose within 60 min. It also revealed that chemisorptions processes outperform physical adsorption. The Pseudo-Second-Order model, which emphasized the importance of chemical adsorption in the removal process, is better suited to represent the adsorption behavior. Excellent matches were found that R2 = 0.99 for KPB-3, R2 = 0.984 for KPB-2 and R2 = 0.989 for KPB-1 indicated strong chemical bonding interactions. Statisctical analysis (ANOVA) was performed using SPSS (version 25) and it was found that pH and concentration had significant influence on OTC adsorption by the hydrogel, with p-values less than 0.05. The study identified that a Kappa carrageenan-based hydrogel with bentonite nano-clay and polyvinyl alcohol (PVA) can efficiently remove OTC from pharmaceutical effluent, with a p-value of 0.054, but weak positive linear associations with pH, temperature, and contact time. This research contributed to sustainable wastewater treatment and environmental engineering.


Asunto(s)
Carragenina , Hidrogeles , Oxitetraciclina , Aguas Residuales , Contaminantes Químicos del Agua , Purificación del Agua , Oxitetraciclina/química , Oxitetraciclina/aislamiento & purificación , Carragenina/química , Aguas Residuales/química , Hidrogeles/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Purificación del Agua/métodos , Cinética , Concentración de Iones de Hidrógeno , Espectroscopía Infrarroja por Transformada de Fourier , Antibacterianos/química
16.
J Funct Biomater ; 15(7)2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39057319

RESUMEN

Pulpotomies and pulpectomies are the most common clinical approach for dental caries in the primary dentition. Reinforced zinc oxide eugenol (ZOE) is an ideal material for filling in the pulp chamber after pulp therapies. The aim of this study was to assess the addition of Cloisite 5A nanoclay material to ZOE and evaluate its antibacterial properties. In this case-control study, the nanoclay nanoparticles were dissolved using a solvent (Eugenol) in different concentrations and their antibacterial properties were assessed using the agar diffusion test and biofilm analysis of Streptococcus mutans (S. mutans), Enterococcus faecalis (E. faecalis), and Escherichia coli (E. coli) in in vitro conditions using the AATCC 100 standards. The diameter of the inhibition zone was measured and assessed statistically using the SPSS software (Version 28, IBM, Chicago, IL, USA) with a significance level of 0.05. The antibacterial properties of the ZOE with nanoclay particles were significantly greater in comparison to the plain ZOE against E. faecalis, S. mutans, and E. coli. The inhibition zone against E. coli under the effect of the ZOE and nanoclay particles combined was significantly higher than that against E. faecalis and S. mutans. The current study showed that the addition of Cloisite 5A nanoclay particles can improve the antibacterial properties of ZOE significantly at certain concentrations.

17.
ACS Nano ; 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39016265

RESUMEN

Medical mineralogy explores the interactions between natural minerals and living organisms such as cells, tissues, and organs and develops therapeutic and diagnostic applications in drug delivery, medical devices, and healthcare materials. Many minerals (especially clays) have been recognized for pharmacological activities and therapeutic potential. Halloysite clay (Chinese medicine name: Chishizhi), manifested as one-dimensional aluminum silicate nanotubes (halloysite nanotubes, HNTs), has gained applications in hemostasis, wound repair, gastrointestinal diseases, tissue engineering, detection and sensing, cosmetics, and daily chemicals formulations. Various biomedical applications of HNTs are derived from hollow tubular structures, high mechanical strength, good biocompatibility, bioactivity, and unique surface characteristics. This natural nanomaterial is safe, abundantly available, and may be processed with environmentally safe green chemistry methods. This review describes the structure and physicochemical properties of HNTs relative to bioactivity. We discuss surface area, porosity and surface defects, hydrophilicity, heterogeneity and charge of external and internal surfaces, as well as biosafety. The paper provides comprehensive guidance for the development of this tubule nanoclay and its advanced biomedical applications for clinical diagnosis and therapy.

18.
Eur J Pharm Sci ; 201: 106858, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39033884

RESUMEN

Protein therapeutics hold immense promise for treating a wide array of diseases. However, their efficacy is often compromised by rapid degradation and clearance. The synthetic smectite clay Laponite emerges as a promising candidate for their sustained delivery. Despite its unique properties allow to load and release proteins mitigating burst release and extending their effects, precise control over Laponite-protein interactions remains challenging since it depends on a complex interplay of factors whose implication is not fully understood yet. The aim of this review article is to shed light on this issue, providing a comprehensive discussion of the factors influencing protein loading and release, including the physicochemical properties of the nanoclay and proteins, pH, dispersion buffer, clay/protein concentration and Laponite degradation. Furthermore, we thoroughly revise the array of bioactive proteins that have been delivered from formulations containing the nanoclay, highlighting Laponite-polymer nanocomposite hydrogels, a promising avenue currently under extensive investigation.


Asunto(s)
Preparaciones de Acción Retardada , Silicatos , Silicatos/química , Proteínas/administración & dosificación , Proteínas/química , Humanos , Animales , Arcilla/química , Sistemas de Liberación de Medicamentos/métodos , Hidrogeles/química , Nanocompuestos/química , Concentración de Iones de Hidrógeno , Liberación de Fármacos , Portadores de Fármacos/química
19.
Nano Lett ; 24(26): 8046-8054, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38912748

RESUMEN

Bacteria invasion is the main factor hindering the wound-healing process. However, current antibacterial therapies inevitably face complex challenges, such as the abuse of antibiotics or severe inflammation during treatment. Here, a drug-free bioclay enzyme (Bio-Clayzyme) consisting of Fe2+-tannic acid (TA) network-coated kaolinite nanoclay and glucose oxidase (GOx) was reported to destroy harmful bacteria via bimetal antibacterial therapy. At the wound site, Bio-Clayzyme was found to enhance the generation of toxic hydroxyl radicals for sterilization via cascade catalysis of GOx and Fe2+-mediated peroxidase mimetic activity. Specifically, the acidic characteristics of the infection microenvironment accelerated the release of Al3+ from kaolinite, which further led to bacterial membrane damage and amplified the antibacterial toxicity of Fe2+. Besides, Bio-Clayzyme also performed hemostasis and anti-inflammatory functions inherited from Kaol and TA. By the combination of hemostasis and anti-inflammatory and bimetal synergistic sterilization, Bio-Clayzyme achieves efficient healing of infected wounds, providing a revolutionary approach for infectious wound regeneration.


Asunto(s)
Antibacterianos , Glucosa Oxidasa , Cicatrización de Heridas , Glucosa Oxidasa/química , Glucosa Oxidasa/metabolismo , Glucosa Oxidasa/farmacología , Cicatrización de Heridas/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/química , Animales , Esterilización/métodos , Arcilla/química , Infección de Heridas/tratamiento farmacológico , Infección de Heridas/microbiología , Hierro/química
20.
Animals (Basel) ; 14(11)2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38891693

RESUMEN

The exploration of natural alternatives to antibiotics for enhancing productivity and performance in dairy cows is a crucial objective in farm animal management. This is the first study aimed at developing and evaluating the physicochemical properties and effects of Arabic gum-nano montmorillonite (AGNM) compost compared to ionophore monensin as feed additives on rumen fermentation, blood metabolites, and milk production of Holstein dairy cows. In a replicated 4 × 4 Latin square design, four multiparous mid-lactation Holstein dairy cows with an average body weight of 520 ± 15 kg were enrolled. The dietary treatments included a control diet (basal diet without feed additives), monensin diet [a basal diet supplemented with 35 mg/kg dry matter (DM) monensin], and AGNM diets comprising basal diet supplemented with two levels: low (L-AGNM) at 1.5 g/kg DM, and high (H-AGNM) at 3 g/kg DM. AGNM as a feed additive demonstrated promising physiochemical parameters, including containing highly bioactive components (α-amyrin and lupeol), functional groups (OH and Si-O), and essential mineral contents (Mg2+). Supplementations with H-AGNM significantly improved ruminal (p = 0.031) concentrations of total volatile fatty acids (VFAs), acetic (p = 0.05) and butyric (p = 0.05), enhanced (p < 0.05) digestibility of fiber and organic matter, while decreased (p = 0.013) estimated methane production. However, an increase (p = 0.04) in blood high-density lipoprotein levels and decrease (p < 0.05) in concentrations of creatinine (CREA), bilirubin (BILT), cholesterol (CHOL), and sodium (Na) were observed with H-AGNM supplementation. Both monensin and H-AGNM improved (p = 0.008) feed efficiency compared to L-AGNM; however, neither AGNM nor monensin affected the milk composition or energy status indicators of the dairy cows. The findings of this study highlight the potential of AGNM as a natural candidate to replace monensin in enhancing ruminal VFA production, nutrient digestibility, feed efficiency, blood metabolites, and milk yield in dairy cows.

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