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1.
Chemosphere ; 363: 142779, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38972455

RESUMO

Nanocomposites have emerged as promising materials for pollutant removal due to their unique properties. However, conventional synthesis methods often involve toxic solvents or expensive materials. In this study, we present a novel ternary nanocomposite synthesized via a simple, cost-effective vacuum filtration method. The composite consists of calcium phosphate (CaP), biowaste-derived nanocellulose (diameter <50 nm) (NC), and chitosan (CH). The nanocomposite exhibited exceptional pollutant removal capabilities due to the hybrid approach of combining adsorption and size exclusion that widens and accelerates pollutant removal. When tested with synthetic wastewater containing 10 ppm of Ni ions and 10 ppm of Congo red (CR) dye, it achieved impressive removal rates of 98.7% for Ni ions and 100% for CR dye. Moreover, the nanocomposite effectively removed heavy metals such as Cd, Ag, Al, Fe, Hg, Mo, Li, and Se at 100%, and Ba, Be, P, and Zn at 80%, 92%, 87%, and 97%, respectively, from real-world municipal wastewater. Importantly, this green nanocomposite membrane was synthesized without the use of harmful chemicals or complex modifications and operated at a high flux rate of 146 L/m2.h.MPa. Its outstanding performance highlights its potential for sustainable pollutant removal applications.

2.
Microb Cell Fact ; 23(1): 189, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956629

RESUMO

Developing special textiles (for patients in hospitals for example) properties, special antimicrobial and anticancer, was the main objective of the current work. The developed textiles were produced after dyeing by the novel formula of natural (non-environmental toxic) pigments (melanin amended by microbial-AgNPs). Streptomyces torulosus isolate OSh10 with accession number KX753680.1 was selected as a superior producer for brown natural pigment. By optimization processes, some different pigment colors were observed after growing the tested strain on the 3 media. Dextrose and malt extract enhanced the bacteria to produce a reddish-black color. However, glycerol as the main carbon source and NaNO3 and asparagine as a nitrogen source were noted as the best for the production of brown pigment. In another case, starch as a polysaccharide was the best carbon for the production of deep green pigment. Peptone and NaNO3 are the best nitrogen sources for the production of deep green pigment. Microbial-AgNPs were produced by Fusarium oxysporum with a size of 7-21 nm, and the shape was spherical. These nanoparticles were used to produce pigments-nanocomposite to improve their promising properties. The antimicrobial of nanoparticles and textiles dyeing by nanocomposites was recorded against multidrug-resistant pathogens. The new nanocomposite improved pigments' dyeing action and textile properties. The produced textiles had anticancer activity against skin cancer cells with non-cytotoxicity detectable action against normal skin cells. The obtained results indicate to application of these textiles in hospital patients' clothes.


Assuntos
Antineoplásicos , Corantes , Prata , Têxteis , Têxteis/microbiologia , Corantes/química , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Prata/farmacologia , Prata/química , Fusarium/efeitos dos fármacos , Streptomyces/metabolismo , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Nanopartículas Metálicas/química , Pigmentos Biológicos/farmacologia , Pigmentos Biológicos/biossíntese , Testes de Sensibilidade Microbiana , Linhagem Celular Tumoral
3.
Cureus ; 16(6): e61548, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38962586

RESUMO

INTRODUCTION: The present study aimed to evaluate and compare the anti-inflammatory effects of two oral rinse formulations, a commercial oral rinse and an Ocimum tenuiflorum and Ocimum gratissimum (nanocomposites, NCs) oral rinse, using in vitro assays commonly employed to assess anti-inflammatory activity. MATERIALS AND METHODS: The anti-inflammatory potential of the oral rinse formulations was assessed using bovine serum albumin (BSA) denaturation, egg albumin denaturation, and membrane stabilization assays. Diclofenac sodium was used as a reference standard in all assays. The inhibition percentages of BSA denaturation and egg albumin denaturation assays, as well as membrane stabilization effects, were measured at various concentrations of the oral rinse formulations. RESULTS: Both the commercial oral rinse and the Ocimum tenuiflorum and Ocimum gratissimum oral rinse demonstrated significant inhibition of BSA denaturation, indicating their anti-inflammatory potential. The Ocimum tenuiflorum and Ocimum gratissimum (NCs) oral rinse consistently showed higher inhibition percentages than the commercial oral rinse, suggesting stronger anti-inflammatory effects in this assay. In the egg albumin denaturation assay, both formulations exhibited inhibition of protein denaturation, with the Ocimum tenuiflorum and Ocimum gratissimum (NCs) oral rinse showing comparable or slightly higher inhibition percentages. The membrane stabilization assay further supported the anti-inflammatory properties of both formulations, with the Ocimum tenuiflorum and Ocimum gratissimum (NCs) oral rinse demonstrating efficacy comparable to diclofenac sodium. DISCUSSION: The results suggest that Ocimum tenuiflorum and Ocimum gratissimum (NCs) oral rinse may possess stronger anti-inflammatory effects compared to commercial oral rinse, as evidenced by higher inhibition percentages in the BSA denaturation assay. Both formulations showed promising anti-inflammatory activity in the egg albumin denaturation and membrane stabilization assays, indicating their potential for mitigating inflammation. CONCLUSION: The Ocimum tenuiflorum and Ocimum gratissimum (NCs) oral rinse exhibits significant anti-inflammatory effects in vitro, potentially surpassing the efficacy of the commercial oral rinse. Further studies are needed to explore the clinical implications of these findings and to validate the anti-inflammatory properties of the Ocimum tenuiflorum and Ocimum gratissimum (NCs) oral rinse in vivo.

4.
Environ Res ; : 119526, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38972341

RESUMO

Rainwater Harvesting (RWH) is increasingly recognized as a vital sustainable practice in urban environments, aimed at enhancing water conservation and reducing energy consumption. This study introduces an innovative integration of nano-composite materials as Silver Nanoparticles (AgNPs) into RWH systems to elevate water treatment efficiency and assess the resulting environmental and energy-saving benefits. Utilizing a regression analysis approach with Support Vector Machines (SVM) and K-Nearest Neighbors (KNN), this study will reach the study objective. In this study, the inputs are building attributes, environmental parameters, sociodemographic factors, and the algorithms SVM and KNN. At the same time, the outputs are predicted energy consumption, visual comfort outcomes, ROC-AUC values, and Kappa Indices. The integration of AgNPs into RWH systems demonstrated substantial environmental and operational benefits, achieving a 57% reduction in microbial content and 20% reductions in both chemical usage and energy consumption. These improvements highlight the potential of AgNPs to enhance water safety and reduce the environmental impact of traditional water treatments, making them a viable alternative for sustainable water management. Additionally, the use of a hybrid SVM-KNN model effectively predicted building energy usage and visual comfort, with high accuracy and precision, underscoring its utility in optimizing urban building environments for sustainability and comfort.

5.
Small ; : e2403552, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963327

RESUMO

In this study, the synthesis of a MXene (Ti3C2Tx)-derived TiO2/starbon (M-TiO2/Starbon-800 °C) nanocomposite using a facile calcination method is explored. High-temperature exposure transforms layered Ti3C2Tx into rod-like TiO2 and starbon into amorphous carbon. The resulting M-TiO2/Starbon-800 °C nanocomposite exhibits a significantly larger surface area and pore volume compared to its individual components, leading to superior electrochemical performance. In a three-electrode configuration, the nanocomposite achieved a specific capacitance (Csp) of 1352 Fg⁻¹ at 1 Ag⁻¹, while retaining more than 99% of its Csp after 50 000 charge/discharge cycles. Furthermore, when incorporated into a two-electrode symmetric coin cell, it demonstrates a Csp of 115 Fg⁻¹ along with exceptional long cycle life. Moreover, the device shows an energy density (ED) of 51 Whkg-1 and a power density (PD) of 7912 Wkg-1 at 5 Ag-1. The enhanced charge storage is attributed to the formation of a porous structure with a high specific surface area resulting from the interaction between M-TiO2 nanorods and starbon, which facilitates efficient ion penetration.

6.
J Comput Chem ; 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38970347

RESUMO

In this study, nanocomposites of g-C3N4/MN4 (where M is Mn, Fe and Co) have been designed using advanced density functional theory (DFT) calculations. A comprehensive analysis was conducted on the geometry, electronic, optical properties, work function, charge transfer interaction and adhesion energy of the g-C3N4/MN4 heterostructures and concluded that g-C3N4/FeN4 and g-C3N4/CoN4 heterojunctions exhibit higher photocatalytic performance than individual units. The better photocatalytic activity can be attributed mainly by two facts; (i) the visible light absorption of both g-C3N4/FeN4 and g-C3N4/CoN4 interfaces are higher compared to its isolated analogs and (ii) a significant enhancement of band gap energy in g-C3N4/FeN4 and g-C3N4/CoN4 heterostructures limited the electron-hole recombination significantly. The potential of the g-C3N4/MN4 heterojunctions as a photocatalyst for the water splitting reaction was assessed by examining its band alignment for water splitting reaction. Importantly, while the electronic and magnetic properties of MN4 systems were studied, this is the first example of inclusion of MN4 on graphene-based material (g-C3N4) for studying the photocatalytic activity. The state of the art DFT calculations emphasis that g-C3N4/FeN4 and g-C3N4/CoN4 heterojunctions are half metallic photocatalysts, which is limited till date.

7.
Int J Biol Macromol ; : 133693, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38971277

RESUMO

The development of new polymer nanocomposites or antibacterial coatings is crucial in combating drug-resistant infections, particularly bacterial infections. In this study, a new chitosan polymer based nanocomposite reinforced with magnesium oxide nanopowders and carbon quantum dots was fabricated by sol-gel technique and coated on 316 L stainless steel. In order to gaining the optimal amount of components to achieve the maximum antibacterial properties, the effect of concentration of nanocomposite components on its antibacterial properties was investigated. Crystal structure, microstructure, elemental dispersion, size distribution, chemical composition and morphology of nanocomposite and coating were characterized with various analyses. The obtained results exhibited that the carbon quantum dot and magnesium oxide nanopowders were distributed uniformly and without agglomeration in the chitosan matrix and created a uniform coating. The antibacterial properties of the synthesized samples against Staphylococcus aureus bacteria (gram positive) were evaluated using disk diffusion and minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) antibacterial tests. The inhibition growth zone formed around the antibiotic and nanocomposite 25 mg/ml under dark and light was about 32 and 14, 11 mm, respectively. Also, MIC and MBC values for final nanocomposite were 62.5 and 125 µg/ml, respectively.

8.
Int J Biol Macromol ; : 133665, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38971294

RESUMO

Functional drugs nano delivery systems manufactured from natural active products are promising for the field of biomedicines. In this study, an anti-ulcerative colitis (UC) curcumin loaded biopolymeric nanocomposite (CZNH) was fabricated and investigated. CZNH nanocomposite was obtained using the anti-solvent precipitation method, wherein curcumin-loaded zein colloidal particles served as the core, while sodium casein (NaCas) and hyaluronic acid (HA) formed the outermost layer of CZNH nanocomposite. Fourier transform infrared (FT-IR) spectrum and transmission electron microscopy (TEM) findings demonstrated that CZNH nanocomposite was a double-layer spherical micelle (250 nm) resulting from the hydrogen bond interactions and electrostatic adsorptions between zein, NaCas, and HA. Furthermore, CZNH nanocomposite exhibited prominent resuspension and storage stability in aqueous solution, which can be stored at 4 °C for approximately 30 days. In vivo anti-UC studies showed that CZNH nanocomposite could effectively alleviate UC symptoms via mediating inflammatory factors [tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and IL-6], myeloperoxidase (MPO), and oxidative stress factor [malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px)]. This study suggested that the CZNH nanocomposite showed great promise as an efficient curcumin nanocarrier for UC therapy.

9.
Discov Nano ; 19(1): 112, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38970729

RESUMO

Hundreds of millions of metric tons of plastic waste are generated globally every year. Processing waste into secondary raw material is preferred over energy production and landfilling. However, mechanical recycling generally deteriorates the properties of plastic waste limiting its range of potential applications. Nanocomposite fabrication is a solution to recycle plastic waste into value-added applications due to improved properties generated by nanomaterial reinforcement, however received little study. The aim of this review is to present the current status, identify research gaps and provide topics for further research of polymer nanocomposites prepared from plastic waste in respect to utilized materials, processing methods, enhanced properties, sustainability, economics, nanomaterial safety, and applications. It is found that morphological, mechanical, thermal, flame retardancy, physical, barrier, electrical and shielding properties of plastic waste can be enhanced with low loadings of different nanomaterials making them promising materials for various applications including electronic, shielding, thermal, packaging, filtration, and water treatment. Utilization of plastic waste instead of virgin polymers can be beneficial in respect to economics and sustainability, but the energy intensive and expensive production of the most nanomaterials, and the plastic waste pretreatment methods can negate these benefits. To enhance sustainability, further research should be conducted on utilization of energy friendly nanomaterials in plastic waste nanocomposites. Further research is needed also on polymer nanocomposite safety because of the unknow composition of the plastic waste and the potential for nanomaterial release during nanocomposite's life cycle. All in all, further research and national regulations and guidance are needed on virgin polymer and plastic waste nanocomposites.

10.
Sci Rep ; 14(1): 15054, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38956159

RESUMO

This study aimed to develop a highly efficient nanocomposite composed of magnetic chitosan/molybdenum disulfide (CS/MoS2/Fe3O4) for the removal of three polycyclic aromatic hydrocarbons (PAHs)-pyrene, anthracene, and phenanthrene. Novelty was introduced through the innovative synthesis procedure and the utilization of magnetic properties for enhanced adsorption capabilities. Additionally, the greenness of chitosan as a sorbent component was emphasized, highlighting its biodegradability and low environmental impact compared to traditional sorbents. Factors influencing PAH adsorption, such as nanocomposite dosage, initial PAH concentration, pH, and contact time, were systematically investigated and optimized. The results revealed that optimal removal efficiencies were attained at an initial PAH concentration of 150 mg/L, a sorbent dose of 0.045 g, pH 6.0, and a contact time of 150 min. The pseudo-second-order kinetic model exhibited superior fitting to the experimental data, indicating an equilibrium time of approximately 150 min. Moreover, the equilibrium adsorption process followed the Freundlich isotherm model, with kf and n values exceeding 7.91 mg/g and 1.20, respectively. Remarkably, the maximum absorption capacities for phenanthrene, anthracene, and pyrene on the sorbent were determined as 217 mg/g, 204 mg/g, and 222 mg/g, respectively. These findings underscore the significant potential of the CS/MoS2/Fe3O4 nanocomposite for efficiently removing PAHs from milk and other dairy products, thereby contributing to improved food safety and public health.


Assuntos
Quitosana , Dissulfetos , Leite , Molibdênio , Nanocompostos , Hidrocarbonetos Policíclicos Aromáticos , Dissulfetos/química , Nanocompostos/química , Quitosana/química , Hidrocarbonetos Policíclicos Aromáticos/química , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Molibdênio/química , Leite/química , Animais , Adsorção , Cinética , Concentração de Íons de Hidrogênio
11.
Artigo em Inglês | MEDLINE | ID: mdl-38980947

RESUMO

Lightweight ablative thermal protection materials (TPMs), which can resist long-term ablation in an oxidizing atmosphere, are urgently required for aerospace vehicles. Herein, carbon fabric/phenol-formaldehyde resin/siloxane aerogels (CF/PFA/SiA) nanocomposite with interpenetrating network multiscale structure was developed via simple and efficient sol-gel followed by atmospheric pressure drying. The ternary networks structurally interpenetrating in macro-, micron-, and the nanoscales, chemically cross-linking at the molecular scale, and silica layer generated by in situ heating synergistically bring about low density (∼0.3 g cm-3), enhanced mechanical properties, thermal stability, and oxidation resistance, and a low thermal conductivity of 81 mW m-1 K-1. More intriguingly, good thermal protection with near-zero surface recession at 1300 °C for 300 s and remarkable thermal insulation with a back-side temperature below 60 °C at 20 mm thickness. The interpenetrating network strategy can be extended to other porous components with excellent high-temperature properties, such as ZrO2 and SiC, which will facilitate the improvement of lightweight ablative TPMs. Moreover, it may open a new avenue for fabricating multifunctional binary, ternary, and even multiple interpenetrating network materials.

12.
Artigo em Inglês | MEDLINE | ID: mdl-38980998

RESUMO

Conductive hydrogels (CHs) are emerging materials for next generation sensing systems in flexible electronics. However, the fabrication of competent CHs with excellent stretchability, adhesion, self-healing, photothermal conversion, multisensing, and environmental stability remains a huge challenge. Herein, a nanocomposite organohydrogel with the above features is constructed by in situ copolymerization of zwitterionic monomer and acrylamide in the existence of carboxylic cellulose nanofiber-carrying reduced graphene oxide (rGO) plus a solvent displacement strategy. The synergy of abundant dipole-dipole interactions and intermolecular hydrogen bonds enables the organohydrogel to exhibit high stretchability, strong adhesion, and good self-healing. The presence of glycerol weakens the formation of hydrogen bonds between water molecules, endowing the organohydrogel with excellent environmental stability (-40 to 60 °C) to adapt to different application scenarios. Importantly, the multimodal organohydrogel presents excellent sensing behavior, including a high gauge factor of 16.3 at strains of 400-1440% and a reliable thermal coefficient of resistance (-4.2 °C-1) over a wide temperature widow (-40 to 60 °C). Moreover, the organohydrogel displays a highly efficient and reliable photothermal conversion ability due to the favorable optical absorbing behavior of rGO. Notably, the organohydrogel can detect accurate human activities at ambient temperature, demonstrating potential applications in flexible intelligent electronics.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38981092

RESUMO

Strong and transparent nanocellulose/montmorillonite (MMT) nanocomposite films with high filler content (≥50 wt %) are emerging as versatile materials for advanced applications due to their excellent optical, barrier, mechanical, and thermal properties, and environmental friendliness. Nonetheless, these films undergo a notable decline in optical and mechanical properties at high MMT loadings. This study first demonstrates that calcium-ion-induced tactoids are the key factor causing disordered structures in nanocomposite films, leading to the degradation of optical and mechanical properties. We then address this issue by employing a Ca2+ removal strategy─dialysis. Through removing 43% of free Ca2+, simultaneous improvements in both properties are observed. For example, in a nanocomposite film with 70 wt % MMT, light transmittance increases from 75.9 to 91.6%, and the tensile strength rises from 100.4 to 139.4 MPa. This work offers insights into developing strong and transparent nanocomposite films with high MMT contents.

14.
Heliyon ; 10(12): e32711, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38952365

RESUMO

Recently, investigation of advanced shielding materials to be used as an alternative to lead apron has become important. In the current study, MgO loaded into PVC matrix as a non-lead modern shielding composite was modeled to evaluate its performance on radiation protective clothing (RPC). Parameters such as mass attenuation coefficient (MAC), mean free path (MFP), flux buildup factor (FBF), transmission factor (TF) and lead equivalent value (LEV) of samples were calculated using MCNPX Code. The simulation of the MCNP code was validated, by comparing the mass attenuation of concrete sample, with standard XCOM data and very good agreement was attended between XCOM and MC Code results. The MAC of nano and micro-sized samples were also compared with pure PVC and it was found that the nano MgO particle exhibits higher attenuation compared to micro MgO particle and pure PVC. The results show that, the MAC of samples increased to 63.13 % in 1.332 MeV with increasing filler concentration of nano MgO to 50 wt% relative to pure PVC. Investigation of LEV shows that nano MgO sample has more effective than Pb in 1.173 and 1.332 MeV gamma ray energy so that it provides 36.46 % and 11.13 % lighter RPC than Pb ones.

15.
Mater Today Bio ; 26: 101104, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38952539

RESUMO

Clinical treatment of diabetic refractory ulcers is impeded by chronic inflammation and cell dysfunction associated with wound healing. The significant clinical application of bFGF in wound healing is limited by its instability in vivo. Sulfur has been applied for the treatment of skin diseases in the clinic for antibiosis. We previously found that sulfur incorporation improves the ability of selenium nanoparticles to accelerate wound healing, yet the toxicity of selenium still poses a risk for its clinical application. To obtain materials with high pro-regeneration activity and low toxicity, we explored the mechanism by which selenium-sulfur nanoparticles aid in wound healing via RNA-Seq and designed a nanoparticle called Nano-S@bFGF, which was constructed from sulfur and bFGF. As expected, Nano-S@bFGF not only regenerated zebrafish tail fins and promoted skin wound healing but also promoted skin repair in diabetic mice with a profitable safety profile. Mechanistically, Nano-S@bFGF successfully coactivated the FGFR and Hippo signalling pathways to regulate wound healing. Briefly, the Nano-S@bFGF reported here provides an efficient and feasible method for the synthesis of bioactive nanosulfur and bFGF. In the long term, our results reinvigorated efforts to discover more peculiar unique biofunctions of sulfur and bFGF in a great variety of human diseases.

16.
Artigo em Inglês | MEDLINE | ID: mdl-38953852

RESUMO

Light weight, thinness, transparency, flexibility, and insulation are the key indicators for flexible electronic device substrates. The common flexible substrates are usually polymer materials, but their recycling is an overwhelming challenge. Meanwhile, paper substrates are limited in practical applications because of their poor mechanical and thermal stability. However, natural biomaterials have excellent mechanical properties and versatility thanks to their organic-inorganic multiscale structures, which inspired us to design an organic-inorganic nanocomposite film. For this purpose, a bio-inspired multiscale film was developed using cellulose nanofibers with abundant hydrophilic functional groups to assist in dispersing hydroxyapatite nanowires. The thickness of the biosustainable film is only 40 µm, and it incorporates distinctive mechanical properties (strength: 52.8 MPa; toughness: 0.88 MJ m-3) and excellent optical properties (transmittance: 80.0%; haze: 71.2%). Consequently, this film is optimal as a substrate employed for flexible sensors, which can transmit capacitance and resistance signals through wireless Bluetooth, showing an ultrasensitive response to pressure and humidity (for example, responding to finger pressing with 5000% signal change and exhaled water vapor with 4000% signal change). Therefore, the comprehensive performance of the biomimetic multiscale organic-inorganic composite film confers a prominent prospect in flexible electronics devices, food packaging, and plastic substitution.

17.
Nanomedicine (Lond) ; : 1-13, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953869

RESUMO

Aim: Today, there is a lack of research studies concerning human acute exposure to nanoparticles (NPs). Our investigation aimed to simulate real-world acute inhalation exposure to NPs released during work with dental nanocomposites in a dental office or technician laboratory. Methods: Blood samples from female volunteers were processed before and after inhalation exposure. Transcriptomic mRNA and miRNA expression changes were analyzed. Results: We detected large interindividual variability, 90 significantly deregulated mRNAs, and 4 miRNAs when samples of participants before and after dental nanocomposite grinding were compared. Conclusion: The results suggest that inhaled dental NPs may present an occupational hazard to human health, as indicated by the changes in the processes related to oxidative stress, synthesis of eicosanoids, and cell division.


What is this article about? We searched for a possible impact of acute inhalation exposure to nanoparticles (NPs) released during the grinding of dental nanocomposites used for teeth reconstruction. The exposure design utilized in our study simulated the acute exposure of the dental staff to the NPs. Our research fills the gaps in knowledge in the field of acute human inhalation exposure to dental nanocomposites.What were the results? Results indicate that the impact of exposure to NPs is dependent on the style of working as well as on the interindividual biological variability among study subjects. Changes in expression levels of genes associated with an increase of oxidative stress, synthesis of eicosanoids (signaling molecules related to e.g., immune responses), and cell division were detected.What do the results of the study mean? All the observed changes may contribute to the pathogenesis of neurodegenerative disorders, carcinogenesis, or problems during pregnancy. Occupational exposure to inhaled NPs, including those generated in dental practice can pose a significant health risk, and protective measures when working with these materials should be considered. More research is needed to compare our results with chronic (long-term) exposure to similar materials to show the hazards related to their inhalation.

18.
Artigo em Inglês | MEDLINE | ID: mdl-38954335

RESUMO

The functionalization of nanoparticles with 2D nanosheets is an effective approach to enhance their functional properties for pollutant removal. This research outlines the synthesis of a 2D-delaminated molybdenum carbide (MXene) chitosan nanocomposite (2D-d-Mo2CTx-Cs NC) with bacterial control and photocatalytic properties for dye adsorption. The nanocomposite includes Tx-surface terminating groups O, OH, and F. In this investigation, the composite was synthesized using the etching method and its formation was confirmed through UV spectra at 288 nm. It was characterized through FTIR, XRD, Particle size, Zetapotential, FESEM, HRTEM, EDAX, and XPS analyses. FTIR spectral analysis of NC suggests that amines are formed through a Schiff base reaction between glutaraldehyde and Cs, or through the interaction of terminal aldehydes and carbonyl groups. The XRD analysis confirmed the crystalline structure of the composite. FESEM images revealed irregularly structured nanosheets (NSs) material in the prepared 2D-d-Mo2CTx-Cs NC samples. HRTEM images revealed 2D-d-Mo2CTx NSs impregnated onto Cs with an average size of 50 nm, as confirmed by a particle size analyzer, with a zeta potential value of - 15 mV. Additionally, Mo, C, N, and O are the most significant elements present in the NC, as confirmed by EDAX and XPS analyses. Further, biocompatibility testing of 2D-d-Mo2CTx-Cs NC yielded positive results. Moreover, under sunlight, the composites effectively adsorbed methylene blue with a 90% adsorption capacity, as confirmed by kinetic studies. Furthermore, the synergistic effect of Cs and d-Mo2CTx NSs resulted in significant antibacterial (50-200 µl of 1 mg/ml) and antibiofilm activity (100 µl of 1 mg/ml) against pathogenic bacteria. Furthermore, this study represents the first report on the use of 2D-d-Mo2CTx-Cs NC for daylight-influenced photocatalytic applications with a bacteria-controlling effect.

19.
Int J Nanomedicine ; 19: 6659-6676, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38975320

RESUMO

Background: Vital pulp therapy (VPT) is considered a conservative treatment for preserving pulp viability in caries and trauma-induced pulpitis. However, Mineral trioxide aggregate (MTA) as the most frequently used repair material, exhibits limited efficacy under inflammatory conditions. This study introduces an innovative nanocomposite hydrogel, tailored to simultaneously target anti-inflammation and dentin mineralization, aiming to efficiently preserve vital pulp tissue. Methods: The L-(CaP-ZnP)/SA nanocomposite hydrogel was designed by combining L-Arginine modified calcium phosphate/zinc phosphate nanoparticles (L-(CaP-ZnP) NPs) with sodium alginate (SA), and was characterized with TEM, SEM, FTIR, EDX, ICP-AES, and Zeta potential. In vitro, we evaluated the cytotoxicity and anti-inflammatory properties. Human dental pulp stem cells (hDPSCs) were cultured with lipopolysaccharide (LPS) to induce an inflammatory response, and the cell odontogenic differentiation was measured and possible signaling pathways were explored by alkaline phosphatase (ALP)/alizarin red S (ARS) staining, qRT-PCR, immunofluorescence staining, and Western blotting, respectively. In vivo, a pulpitis model was utilized to explore the potential of the L-(CaP-ZnP)/SA nanocomposite hydrogel in controlling pulp inflammation and enhancing dentin mineralization by Hematoxylin and eosin (HE) staining and immunohistochemistry staining. Results: In vitro experiments revealed that the nanocomposite hydrogel was synthesized successfully and presented desirable biocompatibility. Under inflammatory conditions, compared to MTA, the L-(CaP-ZnP)/SA nanocomposite hydrogel demonstrated superior anti-inflammatory and pro-odontogenesis effects. Furthermore, the nanocomposite hydrogel significantly augmented p38 phosphorylation, implicating the involvement of the p38 signaling pathway in pulp repair. Significantly, in a rat pulpitis model, the L-(CaP-ZnP)/SA nanocomposite hydrogel downregulated inflammatory markers while upregulating mineralization-related markers, thereby stimulating the formation of robust reparative dentin. Conclusion: The L-(CaP-ZnP)/SA nanocomposite hydrogel with good biocompatibility efficiently promoted inflammation resolution and enhanced dentin mineralization by activating p38 signal pathway, as a pulp-capping material, offering a promising and advanced solution for treatment of pulpitis.


Assuntos
Alginatos , Anti-Inflamatórios , Polpa Dentária , Hidrogéis , Nanocompostos , Polpa Dentária/citologia , Polpa Dentária/efeitos dos fármacos , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Nanocompostos/química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Alginatos/química , Alginatos/farmacologia , Pulpite/terapia , Células-Tronco/efeitos dos fármacos , Células-Tronco/citologia , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Silicatos/química , Silicatos/farmacologia , Ratos , Diferenciação Celular/efeitos dos fármacos , Compostos de Cálcio/química , Compostos de Cálcio/farmacologia , Células Cultivadas , Compostos de Alumínio/química , Compostos de Alumínio/farmacologia , Arginina/química , Arginina/farmacologia , Ratos Sprague-Dawley , Combinação de Medicamentos , Masculino , Óxidos/química , Óxidos/farmacologia
20.
J Mol Model ; 30(7): 235, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38951276

RESUMO

CONTEXT AND RESULTS: A nanocomposite photocatalyst consisting of polyaniline (PANI) and copper oxide (CuO) was successfully synthesized through an in-situ polymerization approach using aniline as the precursor. The synthesized nanocomposite was characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), UV-visible spectroscopy (UV-Vis), determination of the point of zero charge (pHPZC), and scanning electron microscopy (SEM). The photocatalytic efficiency of the PANI-CuO nanocomposite was evaluated in the context of photodegrading Malachite Green (MG) dye under visible light. Malachite Green, a synthetic dye commonly used in the textile and aquaculture industries, is a significant contaminant due to its toxic, mutagenic, and carcinogenic properties, making its removal from water resources crucial for environmental and human health. Distilled water artificially contaminated with MG dye was used as the medium for testing. The parameters influencing the photodegradation efficiency were comprehensively investigated. These parameters included catalyst dosage, reaction time, initial dye concentration, and pH. The results of this study indicate that the degradation efficiency of MG dye displayed an upward trend with time, catalyst dosage, and pH while exhibiting a converse relationship with the initial dye concentration. A degradation rate of 97% was achieved with an initial concentration of 20 mg L-1, employing a catalyst dose of 1.6 g L-1 at pH 6 for a reaction time of 180 min. Furthermore, the reusability of the catalyst was assessed, revealing consistent performance over five consecutive cycles. COMPUTATIONAL AND THEORETICAL TECHNIQUES: Density functional theory (DFT) was employed to optimize the structures of PANI, PANI-CuO, and their respective complexes formed through dye interaction, employing Gaussian software. These calculations employed the B3LYP/6-311G + + (d,p) basis set in an aqueous environment with water serving as the solvent. The kinetics of Malachite Green degradation were analyzed using both first and second-order kinetic models.

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