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Herein, a nanocomposite of Cu,Ce-containing phosphotungstates (Cu,Ce-PTs) with outstanding laccase-like activity was fabricated via a one-pot microwave-assisted hydrothermal method. Notably, it was discovered that both Fe3+ and Cr6+ could significantly enhance the electron transfer rates of Ce3+ and Ce4+, along with generous Cu2+ with high catalytic activity, thereby promoting the laccase-like activity of Cu,Ce-PTs. The proposed system can be used for the detection of Fe3+ and Cr6+ in a range of 0.667-333.33 µg/mL and 0.033-33.33 µg/mL with a low detection limit of 0.135 µg/mL and 0.0288 µg/mL, respectively. The proposed assay exhibits excellent reusability and selectivity and can be used in traditional Chinese medicine samples analysis.
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Cerio , Cromo , Colorimetría , Cobre , Hierro , Lacasa , Cobre/análisis , Cobre/química , Cromo/análisis , Colorimetría/métodos , Lacasa/metabolismo , Lacasa/química , Hierro/análisis , Hierro/química , Cerio/química , Límite de Detección , Ácido Fosfotúngstico/química , Nanocompuestos/química , CatálisisRESUMEN
A rapid photoelectrochemical (PEC) sensor was constructed for nitrite detection in food based on the one-step chemical etching strategy of BiOCl/Zn0.5Cd0.5S (BOC/ZCS) nanocomposites by nitrite. BOC/ZCS heterojunction was prepared by a simple coprecipitation method, and it was found that BOC/ZCS showed significant photoelectrochemical (PEC) activity. The results of this study confirmed that the decrease in the photocurrent of the sensor was linked to the etching of ZCS by nitrite under acidic conditions. Under optimized conditions, the BOC/ZCS-based PEC sensor showed good analytical properties for detecting nitrite, with linear ranges of 1-100 µM and 100-600 µM. The detection limit of the sensor was 0.41 µM (S/N = 3). Excellent repeatability, reproducibility, low background noise, and immunity to interference were demonstrated using the proposed system, and satisfactory results were achieved for the nitrite assay using real samples. These results demonstrate a new method for nitrite detection developed using the proposed PEC sensor.
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Técnicas Electroquímicas , Límite de Detección , Nitritos , Nitritos/análisis , Técnicas Electroquímicas/instrumentación , Bismuto/química , Zinc/química , Zinc/análisis , Nanocompuestos/química , Procesos Fotoquímicos , Contaminación de Alimentos/análisisRESUMEN
Phoxim, extensively utilized in agriculture as an organothiophosphate insecticide, has the potential to cause neurotoxicity and pose human health hazards. In this study, an electrochemical enzyme biosensor based on Ti3C2 MXene/MoS2@AuNPs/AChE was constructed for the sensitive detection of phoxim. The two-dimensional multilayer structure of Ti3C2 MXene provides a robust framework for MoS2, leading to an expansion of the specific surface area and effectively preventing re-stacking of Ti3C2 MXene. Additionally, the synergistic effect of self-reduced grown AuNPs with MoS2 further improves the electrical conductivity of the composites, while the robust framework provides a favorable microenvironment for immobilization of enzyme molecules. Ti3C2 MXene/MoS2@AuNPs electrochemical enzyme sensor showed a significant response to phoxim in the range of 1 × 10-13 M to 1 × 10-7 M with a detection limit of 5.29 × 10-15 M. Moreover, the sensor demonstrated excellent repeatability, reproducibility, and stability, thereby showing its promising potential for real sample detection.
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Técnicas Biosensibles , Técnicas Electroquímicas , Frutas , Oro , Nanopartículas del Metal , Nanocompuestos , Compuestos Organotiofosforados , Titanio , Oro/química , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/métodos , Nanocompuestos/química , Frutas/química , Nanopartículas del Metal/química , Técnicas Biosensibles/instrumentación , Compuestos Organotiofosforados/análisis , Titanio/química , Límite de Detección , Contaminación de Alimentos/análisis , Molibdeno/química , Insecticidas/análisis , Insecticidas/química , Residuos de Plaguicidas/análisis , Residuos de Plaguicidas/químicaRESUMEN
Osteosarcoma, a malignant bone tumor often characterized by high hedgehog signaling activity, residual tumor cells, and substantial bone defects, poses significant challenges to both treatment response and postsurgical recovery. Here, we developed a nanocomposite hydrogel for the sustained co-delivery of bioactive magnesium ions, anti-PD-L1 antibody (αPD-L1), and hedgehog pathway antagonist vismodegib, to eradicate residual tumor cells while promoting bone regeneration post-surgery. In a mouse model of tibia osteosarcoma, this hydrogel-mediated combination therapy led to remarkable tumor growth inhibition and hence increased animal survival by enhancing the activity of tumor-suppressed CD8+ T cells. Meanwhile, the implanted hydrogel improved the microenvironment of osteogenesis through long-term sustained release of Mg2+, facilitating bone defect repair by upregulating the expression of osteogenic genes. After 21 days, the expression levels of ALP, COL1, RUNX2, and BGLAP in the Vis-αPD-L1-Gel group were approximately 4.1, 5.1, 5.5, and 3.4 times higher than those of the control, respectively. We believe that this hydrogel-based combination therapy offers a potentially valuable strategy for treating osteosarcoma and addressing the tumor-related complex bone diseases.
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Neoplasias Óseas , Hidrogeles , Inmunoterapia , Nanocompuestos , Osteosarcoma , Osteosarcoma/patología , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/terapia , Animales , Hidrogeles/química , Nanocompuestos/química , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/patología , Neoplasias Óseas/terapia , Ratones , Inmunoterapia/métodos , Línea Celular Tumoral , Regeneración Ósea/efectos de los fármacos , Humanos , Osteogénesis/efectos de los fármacos , Antígeno B7-H1/metabolismo , Ratones Endogámicos BALB C , Magnesio/químicaRESUMEN
For environmental applications, it is crucial to rationally design and synthesize photocatalysts with positive exciton splitting and interfacial charge transfer. Here, a novel Ag-bridged dual Z-scheme Ag/g-C3N4/CoNi-LDH plasmonic heterojunction was successfully synthesized using a simple method, with the goal of overcoming the common drawbacks of traditional photocatalysts such as weak photoresponsivity, rapid combination of photo-generated carriers, and unstable structure. These materials were characterized by XRD, FT-IR, SEM, TEM UV-Vis/DRS, and XPS to verify the structure and stability of the heterostructure. The pristine LDH, g-C3N4, and Ag/g-C3N4/CoNi-LDH composite were investigated as photocatalysts for water remediation, an environmentally motivated process. Specifically, the photocatalytic degradation of tetracycline was studied as a model reaction. The performance of the supports and composite catalyst were determined by evaluating both the degradation and adsorption phenomenon. The influence of several experimental parameters such as catalyst loading, pH, and tetracycline concentration were evaluated. The current study provides important data for water treatment and similar environmental protection applications.
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Nanocompuestos , Fotólisis , Plata , Contaminantes Químicos del Agua , Purificación del Agua , Nanocompuestos/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Plata/química , Catálisis , Nitrilos/química , Compuestos de Nitrógeno/química , Adsorción , GrafitoRESUMEN
Oral conditions, such as recurrent aphthous stomatitis, are chronic inflammatory disorders that significantly affect the life quality. This study aims to develop a novel buccal mucoadhesive based on methacrylate hydroxypropyl methylcellulose (M-HPMC) and methacrylate lignin (M-SLS) encapsulated with nanostructured lipid carriers (NLCs) for controlled release of alpha-pinene (α-pinene). NLCs with particle sizes of 152 ± 3 nm were prepared by using stearic acid and oleic acid as solid and liquid lipids, respectively. Following the successful synthesis of M-HPMC and M-SLS, various concentrations of α-pinene loaded NLCs (0, 18, 38, and 50 wt%) were encapsulated in M-HPMC/M-SLS hydrogel. It was demonstrated that the physiological and mechanical performances of hydrogels were changed, depending on the NLC content. Remarkably, the incorporation of 18 wt% NLC improved the compressive strength (143 ± 14 kPa) and toughness (17 ± 1 kJ/m3) of M-HPMC/M-SLS hydrogel. This nanocomposite hydrogel considerably decreased dissipated energy from 1.64 kJ/m3 to 0.99 kJ/m3, after a five-cycle compression test. The nanocomposite hydrogel exhibited controlled α-pinene release for up to 96 h which could significantly improve the antioxidant activity of M-HPMC/M-SLS matrix. Moreover, the reinforcing M-HPMC/M-SLS hydrogel with α-pinene-loaded NLCs resulted in increased adhesive strength (113.5 ± 7.5 kPa) to bovine buccal mucosa and cytocompatibility in contact with fibroblasts.
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Monoterpenos Bicíclicos , Hidrogeles , Derivados de la Hipromelosa , Lignina , Nanocompuestos , Lignina/química , Monoterpenos Bicíclicos/química , Monoterpenos Bicíclicos/farmacología , Hidrogeles/química , Hidrogeles/síntesis química , Hidrogeles/farmacología , Nanocompuestos/química , Animales , Derivados de la Hipromelosa/química , Ratones , Metacrilatos/química , Antioxidantes/química , Antioxidantes/farmacología , Antioxidantes/síntesis química , Antioxidantes/administración & dosificación , Fibroblastos/efectos de los fármacosRESUMEN
Background: The high infectivity of coronaviruses has led to increased interest in developing new strategies to prevent virus spread. Silver nanoparticles (AgNPs) and graphene oxide (GO) have attracted much attention in the antiviral field. We investigated the potential antiviral activity of GO and AgNPs combined in the nanocomposite GO-Ag against murine betacoronavirus MHV using an in vitro model. Methods: GO, AgNPs, and GO-Ag characterization (size distribution, zeta potential, TEM visualization, FT-IR, and EDX analysis) and XTT assay were performed. The antiviral activity of GO-Ag nanocomposites was evaluated by RT-qPCR and TCID50 assays. The results were compared with free AgNPs and pure GO. Cell growth and morphology of MHV-infected hepatocytes treated with GO-Ag composites were analyzed by JuLI™Br. Immunofluorescence was used to visualize the cell receptor used by MHV. Ultrastructural SEM analysis was performed to examine cell morphology after MHV infection and GO-Ag composite treatment. Results: A significant reduction in virus titer was observed for all nanocomposites tested, ranging from 3.2 to 7.3 log10 TCID50. The highest titer reduction was obtained for GO 5 µg/mL - Ag 25 µg/mL in the post-treatment method. These results were confirmed by RT-qPCR analysis. The results indicate that GO-Ag nanocomposites exhibited better antiviral activity compared to AgNPs and GO. Moreover, the attachment of AgNPs to the GO flake platform reduced their cytotoxicity. In addition, the GO-Ag composite modulates the distribution of the Ceacam1 cell receptor and can modulate cell morphology. Conclusion: Graphene oxide sheets act as a stabilizing agent, inhibiting the accumulation of AgNPs and reducing their cellular toxicity. The GO-Ag composite can physically bind and inhibit murine betacoronavirus from entering cells. Furthermore, the constant presence of GO-Ag can inhibit MHV replication and significantly limit its extracellular release. In conclusion, GO-Ag shows promise as an antiviral coating on solid surfaces to minimize virus transmission and spread.
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Antivirales , Grafito , Nanopartículas del Metal , Nanocompuestos , Plata , Grafito/farmacología , Grafito/química , Plata/química , Plata/farmacología , Animales , Nanocompuestos/química , Antivirales/farmacología , Antivirales/química , Ratones , Nanopartículas del Metal/química , Virus de la Hepatitis Murina/efectos de los fármacos , Hepatocitos/efectos de los fármacos , Hepatocitos/virología , Infecciones por Coronavirus/tratamiento farmacológico , Infecciones por Coronavirus/virología , Línea CelularRESUMEN
The aim of this study was to develop multifunctional magnetic poly(ε-caprolactone) (PCL) mats with antibacterial properties for bone tissue engineering and osteosarcoma prevention. To provide good dispersion of magnetic iron oxide nanoparticles (IONs), they were first grafted with PCL using a novel three-step approach. Then, a series of PCL-based mats containing a fixed amount of ION@PCL particles and an increasing content of ascorbic acid (AA) was prepared by electrospinning. AA is known for increasing osteoblast activity and suppressing osteosarcoma cells. Composites were characterized in terms of morphology, mechanical properties, hydrolytic stability, antibacterial performance, and biocompatibility. AA affected both the fiber diameter and the mechanical properties of the nanocomposites. All produced mats were nontoxic to rat bone marrow-derived mesenchymal cells; however, a composite with 5 wt.% of AA suppressed the initial proliferation of SAOS-2 osteoblast-like cells. Moreover, AA improved antibacterial properties against Staphylococcus aureus and Escherichia coli compared to PCL. Overall, these magnetic composites, reported for the very first time, can be used as scaffolds for both tissue regeneration and osteosarcoma prevention.
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Ácido Ascórbico , Poliésteres , Staphylococcus aureus , Ingeniería de Tejidos , Poliésteres/química , Ácido Ascórbico/química , Ácido Ascórbico/farmacología , Humanos , Ratas , Animales , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Escherichia coli/efectos de los fármacos , Antibacterianos/química , Antibacterianos/farmacología , Nanopartículas de Magnetita/química , Osteoblastos/metabolismo , Osteoblastos/citología , Línea Celular Tumoral , Osteosarcoma/patología , Huesos , Nanocompuestos/química , Andamios del Tejido/química , Ensayo de MaterialesRESUMEN
Exosomes, extracellular vesicles (EVs) with an average size of 50-150 nm, transfer various biomolecules and exchange signaling molecules between cells in a paracrine manner. Molecular investigations have revealed that EVs can reflect real-time metabolic changes in normal- and cancer-origin cells and thus harbor valid diagnostic biomarkers. Despite these advantages, the detection of low concentrations of cancer cell EVs in biological fluids is still a great challenge. Here, a new electrochemical Exosensor based on platinum-perovskite is developed for the direct detection of EVs using a biotinylated monoclonal CD63 antibody as a capture element. The label-free method exhibited higher sensitivity with a lower limit of quantification of 2000 EVs/µL with a dynamic linear range (LDR) of 2000 to 14,000 EVs/µL compared with other available methods. To enhance the selectivity of detection, EVs were simultaneously sandwiched between secondary antibodies of PSA (prostate-specific antigen), as an FDA-approved prostate cancer biomarker. Data indicated that this Exosensor can distinguish normal and cancer EVs in samples from healthy individuals and prostate cancer patients. Taken together, this technology offers a unique approach to label-free quantification of EVs and cancer detection in the early stages.
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Nanocompuestos , Platino (Metal) , Neoplasias de la Próstata , Humanos , Masculino , Neoplasias de la Próstata/diagnóstico , Platino (Metal)/química , Nanocompuestos/química , Técnicas Biosensibles/métodos , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/inmunología , Biomarcadores de Tumor/análisis , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Exosomas/química , Antígeno Prostático Específico/sangre , Antígeno Prostático Específico/análisis , Antígeno Prostático Específico/inmunología , Límite de Detección , Tetraspanina 30/metabolismoRESUMEN
A sandwich electrochemical sensor was fabricated based on multi-walled carbon nanotubes/ordered mesoporous carbon/AuNP (MWCNTs/CMK-3/AuNP) nanocomposites and porous core-shell nanoparticles Au@PdNPs to achieve rapid and sensitive detection of AFB1 in complex matrices. MWCNTs/CMK-3/AuNP nanocomposite, which was prepared by self-assembly method, served as a substrate material to increase the aptamer loading and improve the conductivity and electrocatalytic activity of the electrode for the first signal amplification. Then, Au@PdNPs, which were synthesized by one-pot aqueous phase method, were applied as nanocarriers loaded with plenty of capture probe antibody (Ab) and signal molecule toluidine blue (Tb) to form the Au@PdNPs-Ab-Tb bioconjugates for secondary signal amplification. The sensing system could still significantly improve the signal output intensity even in the presence of ultra-low concentration target compound due to the dual signal amplification of MWCNTs/CMK-3/AuNP nanocomposites and Au@PdNPs-Ab-Tb. The method exhibited high selectivity, low detection limit (9.13 fg/mL), and strong stability to differentiate AFB1 from other mycotoxins. Furthermore, the sensor has been successfully applied to the quantitative determination of AFB1 in corn, malt, and six herbs, which has potential applications in food safety, quality control, and environmental monitoring.
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Aflatoxina B1 , Técnicas Electroquímicas , Oro , Límite de Detección , Nanopartículas del Metal , Nanotubos de Carbono , Paladio , Oro/química , Nanopartículas del Metal/química , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Paladio/química , Aflatoxina B1/análisis , Aflatoxina B1/inmunología , Nanotubos de Carbono/química , Técnicas Biosensibles/métodos , Anticuerpos Inmovilizados/inmunología , Nanocompuestos/química , Aptámeros de Nucleótidos/química , Contaminación de Alimentos/análisis , Zea mays/química , ElectrodosRESUMEN
The significance of HER-1 and CA 125 lies in their ability to guide cancer diagnosis, treatment, and monitoring, improving personalized care and enhancing prognostic accuracy. The utilization of HER-1 and CA 125 as screening biomarkers for the anticipation of early-stage cancer and monitoring cancer progression is expanding due to the invasive and costly nature of present techniques. In this study, a novel stochastic sensor was developed for the simultaneous determination of HER-1 and CA 125 in whole blood, saliva, and gastric tumor tissue samples using a fast, easy, inexpensive, and portable method. The stochastic sensor was prepared by electropolymerization of cysteine on the surface of the Au-TiO2@rGO/SPCE sensor. The Au-TiO2@rGO nanocomposite was synthesized using a simple chemical reduction process. The proposed sensor showed wide linear concentration ranges and very low limits of quantification (LOQ). The concentration ranges were from 3.9 × 10-14 to 3.9 × 10-8 µg mL-1, with a LOQ of 3.9 × 10-14 µg mL-1 for HER-1. For CA 125, the concentration ranges were from 8.3 × 10-14 to 8.3 × 10-10 U mL-1, with a LOQ of 8.3 × 10-14 U mL-1. Both biomarkers exhibit precise discrimination in different biological samples, with recoveries above 96.78% and RSD values below 0.04%. With a confidence level of 99%, the Student t-test revealed that there is no statistically significant difference between the outcomes obtained by using the poly-Cys/Au-TiO2@rGO/SPCE sensor for screening examinations of biological samples. This was determined because the results were not significantly different from one another.
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Biomarcadores de Tumor , Antígeno Ca-125 , Oro , Grafito , Neoplasias Gástricas , Titanio , Humanos , Antígeno Ca-125/sangre , Antígeno Ca-125/análisis , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/sangre , Titanio/química , Oro/química , Grafito/química , Biomarcadores de Tumor/sangre , Límite de Detección , Técnicas Biosensibles/métodos , Cisteína/sangre , Cisteína/química , Saliva/química , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Procesos Estocásticos , Nanocompuestos/química , Detección Precoz del Cáncer/métodos , Proteínas de la MembranaRESUMEN
Selenium nanoparticles (SeNPs) are used in several sectors as antitumor, antimicrobial, and environmental adsorbents. Thus, the present research objective was the production of bacterial-SeNPs as an active and environmentally-friendly antibacterial and adsorbent agents and application into novel nanocomposite filter. From a total of 25 samples (soil, wastewater, and water) obtained from different locations in Egypt, 60 selenium-resistant bacterial isolates were obtained (on a mineral salt medium supplemented with selenium ions). After screening (based on the conversion of selenium from ionic form to nanoform), a superior bacterial isolate for SeNPs formation was obtained and molecular identified as Bacillus pumilus isolate OR431753. The high yield of SeNPs was noted after optimization (glucose as carbon source, pH 9 at 30 °C). The produced SeNPs were characterized as approximately 15 nm-diameter spherical nanoparticles, in addition to the presence of organic substances around these particles like polysaccharides and aromatic amines (protein residues). Also, they have antibacterial activity increased after formation of nanocomposite with nano-chitosan (SeNPs/NCh) against several pathogens. The antibacterial activity (expressed as a diameter of the inhibitory zone) averaged between 2.1 and 4.3, 2.7 and 4.8 cm for SeNPs and SeNPs/NCh, respectively compared with 1.1 to 1.8 cm for Amoxicillin. The produced nanoselenium/chitosan was used as a biofilter to remove mercury (Hg) and AgNPs as model chemicals with serious toxicity and potential pollutant for water bodies in many industries. The new SeNPs/NCh biofilter has proven highly effective in individually removing mercury and AgNPs from their synthetic wastewaters, with an efficiency of up to 99%. Moreover, the removal efficiency of AgNPs stabilized at 99% after treating them with the syringe filter-Se nanocomposite for 4 cycles of treatment (5 min each).
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Biodegradación Ambiental , Mercurio , Nanocompuestos , Selenio , Plata , Aguas Residuales , Purificación del Agua , Aguas Residuales/química , Nanocompuestos/química , Selenio/química , Mercurio/química , Mercurio/aislamiento & purificación , Purificación del Agua/métodos , Plata/química , Contaminantes Químicos del Agua/química , Nanopartículas del Metal/química , Antibacterianos/farmacología , Antibacterianos/química , Desinfección/métodos , Filtración/métodos , Bacillus/metabolismo , Bacillus/efectos de los fármacos , Quitosano/química , Quitosano/farmacologíaRESUMEN
Silk fibroin (SF), a natural biodegradable and biocompatible protein, has garnered significant attention in biomedical applications due to its impressive properties, including excellent biocompatibility, biodegradability, and mechanical resilience. Nevertheless, its broader usage faces obstacles by its insufficient mechanical strength and electrical conductivity. In order to address these constraints, recent studies have concentrated on combining SF with cutting-edge nanomaterials like MXene and carbon-based materials. This review comprehensively examines the applications and potential of silk fibroin-MXene/carbon-based nanocomposites in biomedical fields. The unique properties of SF, MXene, and carbon-based materials are explored, emphasizing how their combination enhances mechanical strength, conductivity, and biocompatibility. These composites show substantial enhancements in performance for several biomedical applications by utilising the excellent conductivity and mechanical capabilities of MXene and carbonaceous elements. The innovative potential of these nanocomposites is highlighted by critically discussing key applications such as tissue engineering, drug delivery, and biosensing. In addition, the work discusses the latest research progress, difficulties, and future prospects in the sector, providing valuable insights into possible breakthroughs and uses. This review seeks to comprehensively analyse the existing information on silk fibroin-MXene/carbon based nanocomposites in healthcare.
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Materiales Biocompatibles , Fibroínas , Nanocompuestos , Ingeniería de Tejidos , Fibroínas/química , Nanocompuestos/química , Materiales Biocompatibles/química , Ingeniería de Tejidos/métodos , Humanos , Animales , Carbono/química , Sistemas de Liberación de Medicamentos , Técnicas BiosensiblesRESUMEN
In this study, significant improvements in mechanical properties have been seen through the efficient inclusion of Oil Palm Cellulose Nanofibrils (CNF) as nano-fillers into green polymer matrices produced from biomass with a 28 % carbon content. The goal of the research was to make green epoxy nanocomposites utilizing solution blending process with acetone as the solvent with the different CNF loadings (0.1, 0.25, and 0.5 wt%). An ultrasonic bath was used in conjunction with mechanical stirring to guarantee that CNF was effectively dispersed throughout the green epoxy. The resultant nanocomposites underwent thorough evaluation, comparing them to unfilled green epoxy and evaluating their morphological, mechanical, and thermal behavior using a variety of instruments. Field-emission scanning electron microscopy (FE-SEM) was used to validate findings, which showed that the CNF were dispersed optimally inside the nanocomposites. The thermal degradation temperature (Td) of the nanocomposites showed a marginal decrement of 0.8 % in temperatures (from 348 °C to 345 °C), between unfilled green epoxy (neat) and 0.1 wt% of CNF loading. The mechanical test results, which showed a 13.3 % improvement in hardness and a 6.45 % rise in tensile strength when compared to unfilled green epoxy, were in line with previously published research. Overall, the outcomes showed that green nanocomposites have significantly improved in performance.
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Celulosa , Nanocompuestos , Nanofibras , Nanocompuestos/química , Celulosa/química , Nanofibras/química , Temperatura , Resinas Epoxi/química , Resistencia a la Tracción , Tecnología Química Verde/métodos , Aceite de Palma/química , Fenómenos MecánicosRESUMEN
Owing to the correlation between acetone in human's exhaled breath (EB) and blood glucose, the development of EB acetone gas-sensing devices is important for early diagnosis of diabetes diseases. In this article, a noninvasive blood glucose detection device through acetone sensing in EB, based on an α-Fe2O3-multiwalled carbon nanotube (MWCNT) nanocomposite, was successfully developed. Different amounts of α-Fe2O3 were added to the MWCNTs by a simple solution method. The optimized acetone gas sensor showed a response of 5.15 to 10 ppm acetone gas at 200 °C. Also, the fabricated sensor showed very good sensing properties even in an atmosphere with high relative humidity. Since the EB has high humidity, the proposed sensor is a promising device to exactly detect the amount of acetone in EB with high humidity. The sensor was powered by a 3200 mAh battery with the possibility of charging using mains electricity. To increase the reliability and calibration of the sensing device, a practical test was taken to detect acetone EB from 50 volunteers, and a deep learning algorithm (DLA) was used to detect the effect of various factors on the amount of acetone in each person's acetone EB. The proposed device with ±15 errors had almost 85% correct responses. Also, the proposed device had excellent response, short response time, good selectivity, and good repeatability, leading it to be a suitable candidate for noninvasive blood glucose sensing.
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Acetona , Glucemia , Pruebas Respiratorias , Aprendizaje Profundo , Nanocompuestos , Nanotubos de Carbono , Acetona/análisis , Nanotubos de Carbono/química , Humanos , Nanocompuestos/química , Glucemia/análisis , Pruebas Respiratorias/instrumentación , Pruebas Respiratorias/métodos , Compuestos Férricos/química , Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , EspiraciónRESUMEN
PURPOSE: Resins composites are widely used in modern dentistry because of their aesthetic and physical properties. However, discoloration of anterior tooth restorations is a common complaint. Understanding the factors affecting the colour stability of resin composites can lead to longer-lasting repairs. This study aimed to evaluate and compare the colour changes of nanocomposite-based bulk-fill and universal resin composites after immersion in coffee using various polishing systems. MATERIALS AND METHODS: A total of 160 samples were prepared using four different composite groups, with 40 pieces for each combined group. Based on the finishing procedure, the samples were divided into four subgroups for each composite group. Three different polishing procedures were applied to the samples according to the manufacturer's instructions. The control group was not subjected to any treatment. Initial colour measurements were performed using a VITA Easyshade V spectrophotometer. After the initial measurements, the samples were immersed in a Nescafe coffee solution for seven days, followed by colour measurements. Data were analysed using the Kolmogorov-Smirnov test and two-way analysis of variance. Tukey's honest significant difference (HSD) test was used to determine differences between subgroups. RESULTS: The results indicate that bulk-fill resins exhibit more discolouration than universal composites; however, this difference was not statistically significant. The resin group with the smallest discolouration was Ceram X, and the most effective polishing method was Twist polishing. CONCLUSION: Final surface polishing significantly reduced the composites' discolouration. These findings support the selection of appropriate materials and polishing techniques to achieve aesthetic outcomes and colour stability in dental restorations.
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Café , Color , Resinas Compuestas , Pulido Dental , Nanocompuestos , Resinas Compuestas/química , Nanocompuestos/química , Pulido Dental/métodos , Pulido Dental/instrumentación , Ensayo de Materiales , Propiedades de Superficie , Espectrofotometría , HumanosRESUMEN
This study proposes an innovative approach to combat the escalating threat of antibiotic resistance in bacteria by introducing a novel ZnO-propolis nanocomposite (ZnO-P NCs). The overuse of antibiotics, particularly during events like the COVID-19 pandemic, has intensified bacterial resistance, necessitating innovative solutions. The study employs a cost-effective and controllable biosynthesis method to produce ZnO nanoparticles (ZnO-NPs), with propolis extract crucially contributing to the reduction and stabilization of Zn2+ ions. A biodegradable nano-propolis matrix is then created by incorporating ZnO-NPs, forming the ZnO-P NCs. Structural stability is confirmed through FT-IR and Zeta potential analysis, while nanoscale properties are validated via TEM, SEM, and XRD analyses. The antimicrobial efficacy of various substances, including propolis, nano propolis, ethanolic propolis extract, ZnO-NPs, and ZnO-P NCs, is assessed against Gram-negative and Gram-positive bacteria, alongside a comparison with 28 antibiotics. Among the bacteria tested, Pseudomonas aeruginosa PAO1 ATCC15692 was more sensitive (40 mm) to the biosynthesized nanocomposite ZnO-P NCs than to ZnO-NPs (38 mm) and nanopropolis (32 mm), while Escherichia coli was resistant to nanopropolis (0 mm) than to ZnO-NPs (31 mm), and ZnO-P NCs (34 mm). The study reveals a synergy effect when combining propolis with green-synthesized ZnO-NPs in the form of ZnO-P NCs, significantly improving their efficiency against all tested bacteria, including antibiotic-resistant strains like E. coli. The nanocomposite outperforms other materials and antibiotics, demonstrating remarkable antibacterial effectiveness. SEM imaging confirms the disruption of bacterial cell membranes by ZnO-NPs and ZnO-P NCs. The study emphasizes the potential applications of ZnO-NPs integrated into biodegradable materials and underscores the significance of the zinc oxide-propolis nanocomposite in countering antimicrobial resistance. Overall, this research offers a comprehensive solution to combat multidrug-resistant bacteria, opening avenues for novel approaches in infection control.
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Antibacterianos , Pruebas de Sensibilidad Microbiana , Nanocompuestos , Própolis , Óxido de Zinc , Óxido de Zinc/química , Óxido de Zinc/farmacología , Própolis/química , Própolis/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Nanocompuestos/química , Pseudomonas aeruginosa/efectos de los fármacos , Farmacorresistencia Bacteriana/efectos de los fármacos , Humanos , Espectroscopía Infrarroja por Transformada de Fourier , Nanopartículas del Metal/químicaRESUMEN
A new method of reducing the amount of reagent and sample for determination of thrombomodulin (TM) was developed based on competitive immunoreaction using a portable glucometer (PGM). Two types of nanocomposites, TM protein-modified magnetic nanoparticles (MNPs-TM) and TM antibody-/glucose oxidase-modified gold nanoparticles (Ab-GNPs-GOx), were prepared. Their binding product, MNPs-TM-Ab-GNPs-GOx, in the microvolumetric solution was used to catalyze the oxidation of glucose, leading to a decline of the glucose content. The TM-involved competitive immunoreaction had a negative effect on the generation of MNPs-/GNPs-based nanocomposites and inhibited the catalytic oxidation of glucose. The glucose content difference in the microvolumetric solution, which was revealed by a PGM, was in proportion to the logarithm of the TM concentration from 25 ng mL-1 to 2.5 µg mL-1. The limit of detection was 5.7 ng mL-1. Microvolumetric solution and a PGM were used in the measurement, which overcame some deficiencies of classical methods in chemo/biosensing, for example, special instrument, complicated measurement procedure, and high cost.
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Glucosa Oxidasa , Oro , Límite de Detección , Trombomodulina , Oro/química , Humanos , Glucosa Oxidasa/química , Glucosa Oxidasa/metabolismo , Nanopartículas del Metal/química , Técnicas Biosensibles/métodos , Automonitorización de la Glucosa Sanguínea/instrumentación , Inmunoensayo/métodos , Nanopartículas de Magnetita/química , Nanocompuestos/químicaRESUMEN
A novel nanofibrous double-layered biosorbent was fabricated by electrospinning polyethersulfone (PES) doped with a natural deep eutectic solvent (DES), composed of choline chloride (ChCl) and caffeic acid (CFA) in a 3:1 molar ratio, onto a bacterial cellulose (BC) substrate. The pristine PES/DES@BC biosorbent was employed in a thin film-solid phase microextraction (TF-SPME) to extract 12 multiclass pesticides from water. Characterization techniques, including ATR-FTIR, FT-NMR, SEM, and nitrogen adsorption/desorption isotherms, confirmed the nanofibrous structure of the electrospun PES-DES and BC biopolymer. The method was validated for matrix effect, specificity, reproducibility, limits of quantification (0.03-0.10 µg/L), and enrichment factor (7-14). Matrix-match calibration linearity ranged from 0.03 to 500 µg/L, with determination coefficients (r²) between 0.9884 and 0.9994. Intra-day and inter-day relative standard deviations (RSDs) were 1.2-3.6 % and 7.0-9.3 %, respectively. The composition of the biosorbent and the fabrication reproducibility across different batches were also thoroughly examined. The accuracy was evaluated by measuring extraction recoveries in six environmental water samples, which ranged from 75 to 105 % (RSDs < 9.0 %). Furthermore, the sustainability of the method was evaluated with the Analytical Eco-Scale and Analytical Greenness metrics. To our knowledge, this study represents the first synthesis and combination of [ChCl:[CFA] DES with PES to create a double-layered nanofiber biosorbent, as well as its application for extracting various pesticide groups from water samples.
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Celulosa , Disolventes Eutécticos Profundos , Nanocompuestos , Plaguicidas , Polímeros , Microextracción en Fase Sólida , Sulfonas , Contaminantes Químicos del Agua , Nanocompuestos/química , Celulosa/química , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/química , Polímeros/química , Plaguicidas/análisis , Plaguicidas/aislamiento & purificación , Disolventes Eutécticos Profundos/química , Reproducibilidad de los Resultados , Microextracción en Fase Sólida/métodos , Sulfonas/química , Límite de Detección , Nanofibras/química , Adsorción , Tecnología Química Verde/métodosRESUMEN
BACKGROUND: Control of rifampicin-resistant tuberculosis (RR-MTB) requires novel technologies for restoring the anti-TB efficacy of priority drugs. We sought to evaluate the ability of nanotechnology application in the recovery of the anti-tuberculosis efficacy of rifampicin. METHODS: Nanocomposite- standard dose of rifampicin and 20 nm silver nanoparticles (AgNPs) suspension solution of 6 different concentrations: 0.25%; 0.5%; 1%; 2.5%; 5%; and 10%, were supplemented to 70 rifampicin-resistant mycobacterium tuberculosis (RR-MTB) isolates. The control arm consisted of 35 RR-MTB isolates and AgNPs suspension with identical concentrations. The inhibitory effect of nanocomposites was evaluated by MTB growth rate using the BACTECTM MGIT 960TM. The safety assessment of single-use AgNPs was conducted in experimental animals. RESULTS: The suppression process of AgNPs on RR-MTB isolates started with 2,5% nanocomposite solution application and full suppression was achieved in 5% and 10% nanocomposite solutions. A standard dose of rifampicin and a 2.5% solution of AgNPs increased the minimal inhibitory effect on RR-MTB by 10% (total 80%) vs the isolated use of a 2.5% solution of AgNPs (70%). An experiment on animals revealed the complete safety of a single injection of ultra-high doses of AgNPs. CONCLUSION: The study showed the potentiating effect of AgNPs in overcoming the resistance of MTB to rifampicin providing a scientific basis for further research.