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1.
Biomed Mater ; 19(3)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38471148

RESUMO

The combination of photodynamic (PDT) and chemodynamic therapy (CDT) for cancer treatment has gathered a lot of attention in recent years. However, its efficacy is severely limited by elevated levels of hypoxia and glutathione (GSH) in the tumor microenvironment (TME). Multifunctional nanoparticles that can help remodel the TME while facilitating PDT/CDT combination therapy are the need of the hour. To this effect, we have developed O2self-supplying, free radical generating nanohybrids that exhibit near infra-red (NIR) triggered photothermal (PTT)/photo-induced thermodynamic (P-TDT) and CDT for efficient breast cancer treatment. The surface of nanohybrids has been further modified by biointerfacing with cancer cell membrane. The biomimetic nanohybrids have been comprehensively characterized and found to exhibit high 2,2'-azobis-[2-(2-imidazolin-2-yl)propane] dihydrochloride (AIPH) loading, GSH depletion, oxygen self-supply with TME responsive AIPH release. Biological activity assays demonstrate efficient cellular uptake with homotypic targeting, excellent hemo- and cytocompatibility as well as high intracellular reactive oxygen species generation with synergistic cytotoxicity against tumor cells. The multifunctional nanohybrid proposed in the present study provides an attractive strategy for achieving NIR responsive, tumor targeted PTT/P-TDT/CDT combination therapy for breast cancer treatment.


Assuntos
Neoplasias da Mama , Nanopartículas , Neoplasias , Humanos , Feminino , Terapia Combinada , Biomimética , Membrana Celular , Glutationa , Termodinâmica , Neoplasias da Mama/terapia , Linhagem Celular Tumoral , Peróxido de Hidrogênio , Microambiente Tumoral
2.
Nanomaterials (Basel) ; 14(5)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38470767

RESUMO

We consider the influence of different nanoparticles or micrometre-scale colloidal objects, which we commonly refer to as particles, on liquid crystalline (LC) orientational order in essentially spatially homogeneous particle-LC mixtures. We first illustrate the effects of coupling a single particle with the surrounding nematic molecular field. A particle could either act as a "dilution", i.e., weakly distorting local effective orientational field, or as a source of strong distortions. In the strong anchoring limit, particles could effectively act as topological point defects, whose topological charge q depends on particle topology. The most common particles exhibit spherical topology and consequently act as q = 1 monopoles. Depending on the particle's geometry, these effective monopoles could locally induce either point-like or line-like defects in the surrounding LC host so that the total topological charge of the system equals zero. The resulting system's configuration is topologically equivalent to a crystal-like array of monopole defects with alternating topological charges. Such configurations could be trapped in metastable or stable configurations, where the history of the sample determines a configuration selection.

3.
Materials (Basel) ; 17(5)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38473560

RESUMO

From 1990 to 2024, this study presents a groundbreaking bibliometric and sentiment analysis of nanocomposite literature, distinguishing itself from existing reviews through its unique computational methodology. Developed by our research group, this novel approach systematically investigates the evolution of nanocomposites, focusing on microstructural characterization, electrical properties, and mechanical behaviors. By deploying advanced Boolean search strategies within the Scopus database, we achieve a meticulous extraction and in-depth exploration of thematic content, a methodological advancement in the field. Our analysis uniquely identifies critical trends and insights concerning nanocomposite microstructure, electrical attributes, and mechanical performance. The paper goes beyond traditional textual analytics and bibliometric evaluation, offering new interpretations of data and highlighting significant collaborative efforts and influential studies within the nanocomposite domain. Our findings uncover the evolution of research language, thematic shifts, and global contributions, providing a distinct and comprehensive view of the dynamic evolution of nanocomposite research. A critical component of this study is the "State-of-the-Art and Gaps Extracted from Results and Discussions" section, which delves into the latest advancements in nanocomposite research. This section details various nanocomposite types and their properties and introduces novel interpretations of their applications, especially in nanocomposite films. By tracing historical progress and identifying emerging trends, this analysis emphasizes the significance of collaboration and influential studies in molding the field. Moreover, the "Literature Review Guided by Artificial Intelligence" section showcases an innovative AI-guided approach to nanocomposite research, a first in this domain. Focusing on articles from 2023, selected based on citation frequency, this method offers a new perspective on the interplay between nanocomposites and their electrical properties. It highlights the composition, structure, and functionality of various systems, integrating recent findings for a comprehensive overview of current knowledge. The sentiment analysis, with an average score of 0.638771, reflects a positive trend in academic discourse and an increasing recognition of the potential of nanocomposites. Our bibliometric analysis, another methodological novelty, maps the intellectual domain, emphasizing pivotal research themes and the influence of crosslinking time on nanocomposite attributes. While acknowledging its limitations, this study exemplifies the indispensable role of our innovative computational tools in synthesizing and understanding the extensive body of nanocomposite literature. This work not only elucidates prevailing trends but also contributes a unique perspective and novel insights, enhancing our understanding of the nanocomposite research field.

4.
ACS Sens ; 9(3): 1465-1474, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38411899

RESUMO

In the realm of NH3 gas-sensing applications, the electrically conductive nature of Ti3C2Tx MXene, adorned with surface terminations such as -O and -OH groups, renders it a compelling material. However, the inherent challenges of atmospheric instability and selectivity in the presence of gas mixtures have prompted the exploration of innovative solutions. This work introduces a strategic solution through the deposition of a mixed-matrix membrane (MMM) composed of poly(vinylidene fluoride) (PVDF) as the matrix and zeolitic imidazolate framework-67 (ZIF-67) as the filler. This composite membrane acts as a selective filter, permitting the passage of a specific gas, namely NH3. Leveraging the hydrophobic and chemically inert nature of PVDF, the MMM enhances the atmospheric stability of Ti3C2Tx by impeding water molecules from interacting with the MXene. Furthermore, ZIF-67 is selective to NH3 gas via acid-base interactions within the zeolite group and selective pore size. The Ti3C2Tx sensor embedded in the MMM filter exhibits a modest 1.3% change in the sensing response to 25 ppm of NH3 gas compared to the response without the filter. This result underscores the filter's effectiveness in conferring selectivity and diffusivity, particularly at 35% relative humidity (RH) and 25 °C. Crucially, the hydrophobic attributes of PVDF impart heightened stability to the Ti3C2Tx sensor even amidst varying RH conditions. These results not only demonstrate effective NH3 detection but also highlight the sensor's adaptability to diverse environmental conditions, offering promising prospects for practical applications.


Assuntos
Polímeros de Fluorcarboneto , Nitritos , Polivinil , Titânio , Elementos de Transição , Zeolitas , Temperatura
5.
Biomed Mater ; 19(2)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38387058

RESUMO

In this study, porous magnesium (Mg) scaffolds were investigated with varying strontium (Sr) and constant zinc (Zn) concentrations through the powder metallurgy process. All samples were examined at room temperature to evaluate their microstructure, mechanical andin-vitrodegradation behaviour and biological properties. Results indicated that adding Sr was associated with fine average grain size, increased mechanical strength, and a decreased corrosion rate. All samples show tiny isolated and open interconnected pores (porosities: 18%-30%, pores: 127-279 µm) with a suitable surface roughness of less than 0.5 µm. All the provided samples possess mechanical and hemocompatible properties that closely resemble natural bone. Mg-4Zn-2Sr has the highest hardness (102.61 ± 15.1 HV) and compressive strength (24.80 MPa) than Mg-4Zn-0.5Sr (85 ± 8.5 HV, 22.14 MPa) and Mg-4Zn-1Sr (97.71 ± 11.2 HV, 18.06 MPa). Immersion results revealed that samples in phosphate-buffered saline solutions have excellent degradability properties, which makes them a promising biodegradable material for orthopaedic applications. The scaffold with the highest Sr concentration shows the best optimised mechanical and degradation behaviour out of the three porous scaffolds, with a 2.7% hemolysis rate.


Assuntos
Magnésio , Ortopedia , Porosidade , Próteses e Implantes , Morte Celular , Estrôncio
6.
ACS Appl Bio Mater ; 7(1): 203-219, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38176074

RESUMO

The present work investigates the use of age-strengthened Mg-Zn-Mn-Ca/xZnO as resorbable materials in temporary orthopedic implants. Quaternary Mg-Zn-Mn-Ca alloy, reinforced with zinc oxide particles, was stir-cast, followed by solution treatment and a range of aging treatments. Optical and electron microscopy, mechanical, electrochemical, immersion, and dynamic mechanical testing, with biocompatibility assessment were carried out. The observed 2θ shift in the (101) peaks of ZMX611/ZnO-ST and ZMX611/ZnO-H indicated lattice shrinkage. The formation of Mg7Zn3 and Ca2Mg6Zn3 in the grain boundary compositions was observed. ZMX611/ZnO-ST had a smaller ß-phase fraction, indicating a finer microstructure. ZMX611/ZnO-H had the highest tensile yield strength (102.97 ± 3.92 MPa), and ZMX611/ZnO-ST showed the highest ultimate tensile strength (127.21 ± 7.48 MPa), indicating precipitation hardening of Zn enrichment. The uniformly dispersed secondary phases played a dual role in corrosion behavior. ZMX611/ZnO-ST showed a better cytocompatibility response among all samples. Composite materials exhibited satisfactory biocompatibility and mechanical compatibility as indicated by in silico results of deviatoric strain-based mechanical stimuli at the fracture interface.


Assuntos
Materiais Biocompatíveis , Óxido de Zinco , Materiais Biocompatíveis/química , Teste de Materiais , Zinco/química , Fixação de Fratura
7.
Biol Trace Elem Res ; 202(1): 268-290, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37060542

RESUMO

Zinc oxide nanoparticles (ZnO NPs) have involved a lot of consideration owing to their distinctive features. The ZnO NPs can be described as particularly synthesized mineral salts via nanotechnology, varying in size from 1 to 100 nm, while zinc oxide (ZnO), it is an inorganic substrate of zinc (Zn). The Zn is a critical trace element necessary for various biological and physiological processes in the body. Studies have revealed ZnO NPs' efficient immuno-modulatory, growth-promoting, and antimicrobial properties in poultry birds. They offer increased bioavailability as compared to their traditional sources, producing better results in terms of productivity and welfare and consequently reducing ecological harm in the poultry sector. However, they have also been reported for their toxicological effects, which are size, shape, concentration, and exposure route dependent. The investigations done so far have yielded inconsistent results, therefore, a lot of additional studies and research are required to clarify the harmful consequences of ZnO NPs and to bring them to a logical end. This review explores an overview of efficient possible role of ZnO NPs, while comparing them with other nutritional Zn sources, in the poultry industry, primarily as dietary supplements that effect the growth, health, and performance of the birds. In addition to the anti-bacterial mechanisms of ZnO NPs and their promising role as antifungal, and anti-colloidal agent, this paper also covers the toxicological mechanisms of ZnO NPs and their consequent toxicological hazards to vital organs and the reproductive system of poultry birds.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Oligoelementos , Óxido de Zinco , Animais , Óxido de Zinco/toxicidade , Óxido de Zinco/química , Aves Domésticas , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/química , Zinco
8.
Int J Biol Macromol ; 255: 127893, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37949284

RESUMO

The present work deals with the construction of a nanoscale system that can deliver chemotherapeutic agents to breast cancer cells in a controlled trend. The framework consists of gallic acid functionalized copper oxide nanoparticles (Ga@CuO) loaded with paclitaxel (PTX). To control the release of PTX, Ga@CuO NPs were coated with a red seaweed, Kappa carrageenan (K-carr) layer, and embellished with folic acid (FA) to enhance the targeted chemotherapy approach. Encapsulation efficiency and loading capacity of PTX loaded Ga@CuO@K-carr/FA NPs were estimated to be 84.58 ± 1.85 % and 13.2 ± 0.22 %, respectively. Moreover, the presence of strong cytotoxicity with an IC50 value of 12 ± 2.0 µg/mL and a high percentage of apoptotic cells (40.25 %) within the treated MCF-7 cells provided further evidence of the effective release of PTX from the loaded Ga@CuO@K-carr/FA. Consequently, it was discovered that the altered metabolic activity of cancer cells and the inhibition of cell proliferation are distinct features of apoptotic cell death induced by reactive oxygen species (ROS). Also, it was noted that treatment of MCF-7 cells with Ga@CuO-PTX@K-carr/FA caused a reduction in mitochondrial membrane potential that resulted in cellular apoptosis. Taken together, this study sheds light on the rational design of Ga@CuO-PTX@K-carr/FA, which offers a suitable candidate to transport drugs at an intracellular level for targeted chemotherapy.


Assuntos
Neoplasias da Mama , Nanopartículas , Humanos , Feminino , Paclitaxel/farmacologia , Carragenina , Polifenóis , Linhagem Celular Tumoral , Neoplasias da Mama/tratamento farmacológico , Ácido Fólico
9.
Int J Pharm ; 645: 123374, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37673278

RESUMO

Multifunctional nanoparticles for treatment in cancer are getting more and more attention recently. In this study, we employed a novel polydopamine (PDA) framework-based gold nanoparticles as a carrier of an antimetabolite drug, 5-Fluorouracil (5-FU). Folic acid (FA) was embellished onto the surface of nanoparticle imparting the nanosystem with remarkable tumor-targeting abilities through its precise binding with FA receptor that is notably overexpressed in breast cancer cells. PDA served as a photothermal treatment (PTT) agent and a gatekeeper to regulate drug release since it is highly pH-sensitive and might lengthen the residency period while simultaneously enhancing water solubility and biological compatibility of nanomaterials. Gold nanoparticles (Au NPs) end up serving as both a drug delivery platform and a source of substantial photothermal effects, culminating in synergistically coupled chemo-photothermal therapy. The PDA@Au@FA nanocomplex, loaded with 5-FU, is biocompatible, features strong NIR absorption and photothermal conversion, and can control drug release in pH/NIR dual response environment. The cell viability in PDA@Au@5-FU-FA group with NIR irradiation in 48 h was only 20.1 ± 2.6%. In addition, apoptosis staining experiments revealed greater cellular uptake of PDA@Au@5-FU-FA by MCF-7 cells. Therefore, PDA@Au@5-FU-FA nanocomplex that we postulated herein may be a potential contender for effective curative treatment for breast cancer.


Assuntos
Neoplasias da Mama , Nanopartículas Metálicas , Nanopartículas , Humanos , Feminino , Liberação Controlada de Fármacos , Ouro/uso terapêutico , Fototerapia , Neoplasias da Mama/tratamento farmacológico , Fluoruracila/uso terapêutico , Doxorrubicina/uso terapêutico , Linhagem Celular Tumoral
10.
J Mech Behav Biomed Mater ; 146: 106073, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37625281

RESUMO

Zinc has currently emerged as a promising biodegradable metal due to its good biocompatible property and promising degradation behaviour. Additionally, inadequate mechanical strength and a lower cell viability value fall short of what is needed for biodegradable implants. In this work, we used the stir-casting process to create a biodegradable Zn-1Mg-1Cu-1HA (ZHA) and Zn-1Mg-1Cu-1ZrO2 (ZZR) composite onto which ceramics composite coating is done by electrodeposition technique to enhance the biocompatibility. The as-cast sample has uniformly distributed fine MgZn2 and CuZn2 phases in a α-Zn matrix, according to microstructural analysis. The mechanical test confirms that ZZR composite exhibited high tensile and compressive properties, including compressive yield strength of 369.562 MPa, a yield tensile strength of 88.725 MPa and ultimate tensile strength of 116.21 MPa. The result of potentiodynamic polarization test shows that the coated ZZR composite sample gives a corrosion rate value of 0.112 mm/year. From immersion tests, the degradation rate obtained a much lower value after immersing the sample in PBS solution for 55 days (0.067 mm/year). Moreover, an extract of coated ZZR composite shows good cell viability in comparison to the uncoated sample at a concentration of 25%, 50% and 75%. Also, the hemolysis percentage for coated ZZR sample is lower than the other prepared uncoated sample (3.072%) Overall, the result obtained proves that the coated ZZR composite sample can be expected as a capable material for implant application.


Assuntos
Implantes Absorvíveis , Galvanoplastia , Morte Celular , Sobrevivência Celular
11.
Nanotechnology ; 34(48)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37619535

RESUMO

Worldwide, dyes are significant pollutants present in water because of their huge consumption for industrial purposes. These dyes as pollutants cause serious health issues in human beings and cause the loss of aquatic biodiversity. So, remediation of pollutants like dyes from wastewater is the need of the hour. In the present study, we greenly synthesizedSpirulina-mediated titanium oxide nanoparticles (STONPs) for the adsorptive remediation of methyl orange (MO) (anionic) and malachite green (MG) (cationic) dyes. The characterization of STONPs was performed by Field emission scanning electron microscopy (FESEM) with EDX, FT-IR, XRD, Zeta Potential and particle size analyzer, Raman spectroscopy, and UV-vis. The various parameter effects like pH, nano-adsorbent dose, the concentration of dye, contact time, and temperature were also examined. Adsorption isotherms like Langmuir, Freundlich, and Temkin, and Kinetics models like Elovich Model, Pseudo 1st, intraparticle diffusion model (IPDM), Pseudo 2nd order, and the thermodynamic model were applied for a stronger interpretation. Theqmaxattained utilizing the Langmuir adsorption model was 272.4795 mg g-1and 209.6436 mg g-1for MO and MG correspondingly. The regeneration study of synthesized nanomaterials up to five cycles was also done. We found that greenly synthesized STONPs have great potential for adsorptive remediation for both MG and MO dyes.


Assuntos
Poluentes Ambientais , Nanopartículas , Humanos , Corantes , Adsorção , Espectroscopia de Infravermelho com Transformada de Fourier , Cátions , Extratos Vegetais
12.
bioRxiv ; 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37577702

RESUMO

Macrophages engulf micron-sized objects including pathogens and cell debris by phagocytosis, serving a fundamental role in immune defense and homeostasis 1, 2 . Although the internalization process of suspended particles has been thoroughly investigated 3, 4 , it is incompletely understood how macrophages internalize surface-bound objects by overcoming the surface binding. Here, we prepared a force-sensing platform which visualizes cell-substrate adhesive force by fluorescence. Macrophages are tested on this platform with micron-sized objects (E. coli, microbeads and silver nanorods) immobilized. By co-imaging integrin-transmitted forces and corresponding structural proteins, we discovered that macrophages consistently form integrin-mediated adhesion structures on the surface to encircle and pinch off surface-bound objects. We termed these structures phagocytic adhesion rings (PAR) and showed that integrin tensions in PARs are resulted from local actin polymerization, but not from myosin II. We further demonstrated that the intensity of integrin tensions in PARs is correlated with the object surface-bound strength, and the integrin ligand strength (dictating the upper limit of integrin tensions) determines the phagocytosis efficiency. Collectively, this study revealed a new phagocytosis mechanism that macrophages form PARs to provide physical anchorage for local F-actin polymerization that pushes and lifts off surface-bound objects during phagocytosis.

13.
Environ Sci Pollut Res Int ; 30(42): 95039-95053, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37580476

RESUMO

More than 60% of India's population relies on agriculture as their primary source of income, making it the nation's most important economic sector. Rice husk (often abbreviated as RH) is one of the most typical by-products of agricultural production. Every five tonnes of rice that is harvested results in the production of one tonne of husk. The concept of recycling and reusing waste from agricultural production has received interest from a variety of environmental and industrial perspectives. A wide variety of nanomaterials, including nano-zeolite, nanocarbon, and nano-silica, have been discovered in agro-waste. From rice cultivation to the finished product, there was a by-product consisting of husk that comprised 20% of the overall weight, or RH. The percentage of silica in RH ash ranges from 60 to 40%, with the remaining percentage consisting of various minerals. As a direct consequence of this, several distinct approaches to generating and extracting nanomaterial from rice husk have been developed. Because it contains a significant amount of cellulose and lignin, RH is an excellent and economical source of carbon precursor. The goal of this chapter is to produce carbon-based nanomaterials from RH.


Assuntos
Nanoestruturas , Oryza , Carbono
14.
Nanotechnology ; 34(44)2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37527630

RESUMO

In addition to their adjustable functionality, structural tunability, and compositional tunability, metal-organic frameworks (MOFs), often known as MOFs, are a distinct form of crystalline porous material. When reduced to two dimensions, ultrathin layers of MOF retain more of its fantastic external features, which is beneficial for a variety of technological applications. Due to their ultrathin atomic-level thickness, easily modifiable structure, and huge surface area, 2D MOF nanosheets and nanocomposites have been the subject of significant research. MOFs are considered intriguing materials for removing toxic contaminants among the novel technologies taken into account in water remediation processes because they exhibit numerous qualities that make them advantageous in water treatment: large surface area, easily functionalizable cavities, a few stable in water, large-scale synthesis, etc Nowadays, water pollution is a rising environmental concern that must be addressed. Due to their special qualities, which include chemical activities, a variety of functionalities, excellent stability, and the ability to be modified for the detection or adsorption of particular molecules, MOFs are widely used in detecting and removing contaminants from water. This review explores most recent wastewater treatment advancements (WWT) using the 2D MOFs mechanism.

15.
Nanotechnology ; 34(35)2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37167957

RESUMO

Bio-nanotechnology is one of the new and sound techniques that have various advantages over conventional methods of wastewater treatment. The utilization of nanomaterials like nanoparticles for wastewater treatment is emerging field of research. Both physical and chemical methods can be used for nanoparticle synthesis, but synthesis based on algae (biological method) has numerous advantages over others as it is environmentally friendly and sustainable. Top-down and bottom-up are the two approaches used for nanoparticle synthesis, generally, bio-reduction (bottom-up approach) is used to synthesize nanoparticles. Nanoparticles can be synthesized inside the cell of algae called intracellular synthesis and outside on the surface of the cell called extracellular synthesis. Temperature, pH, and reaction time are some of the factors that can influence the synthesis, size, and properties of nanoparticles. Characterization of nanoparticles is carried out with the help of the techniques like UV-visible spectroscopy (UV-vis), x-ray diffraction, Fourier transfer infrared spectroscopy, etc. Algal nanoparticles are highly efficient in the remediation of contaminants like heavy metals and dyes from wastewater. In the present review, the utilization of algal nanoparticles for wastewater treatment containing contaminants like heavy metals, and dye, and various methods of synthesis of nanoparticles from algae are discussed. Moreover, the challenges and opportunities present in this field are also highlighted. As this field is in its initial stage, therefore, a lot of research gaps are present, which can only be filled by further new research.


Assuntos
Nanopartículas Metálicas , Metais Pesados , Nanopartículas , Nanoestruturas , Águas Residuárias , Nanopartículas/química , Nanotecnologia , Nanopartículas Metálicas/química
16.
ACS Biomater Sci Eng ; 9(5): 2764-2779, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-37079362

RESUMO

The present work aims to assess the age hardening of microalloyed Mg-Zn-Mn alloy reinforced with Ca10(PO4)6(OH)2 (hydroxyapatite, HAp) particles to impart mechanical strength without deteriorating their degradation and biocompatibility behavior for their suitability toward resorbable fixation devices. The hydroxyapatite powder was synthesized with high purity. Mg-Zn-Mn (ZM31) and Mg-Zn-Mn/HAp (ZM31/HAp) were stir-cast, homogenized, and solution-treated to achieve uniform dissolution. Further, they were given a range of aging treatments (175 °C for 0, 5, 10, 25, 50, and 100 h), and the age hardening was measured as Vickers microhardness. The solution-treated and peak-aged (175 °C × 50 h) samples were further investigated using optical and electron microscopy, tensile testing, electrochemical corrosion testing, dynamic mechanical analysis, and biocompatibility. The peak-aged ZM31 sample revealed the highest ultimate strength (134.09 ± 5.46 MPa). The aging treatment resulted in notable improvement in ductility in ZM31 (8.72 ± 1.38%) and yield strength in ZM31/HAp (82.50 ± 1.43 MPa). The rapid strain-hardening behavior was distinctly visible in peak-aged samples in the initial stage of deformation. The amplitude-dependent internal friction confirmed the active solute and age-hardening mechanisms in agreement with the Granato-Lücke model. All samples displayed favorable cell viability (>80%) and cell adhesion behavior; however, their hemocompatibility and biodegradation need further consideration.


Assuntos
Durapatita , Magnésio , Durapatita/farmacologia , Durapatita/química , Magnésio/farmacologia , Magnésio/química , Teste de Materiais , Ligas/farmacologia , Ligas/química , Fricção
17.
Eur Phys J E Soft Matter ; 46(3): 11, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36884157

RESUMO

In this study, we used radical polymerization to create poly (N-isopropyl acrylamide)-co-poly (sodium acrylate) [PNIPAM-co-PSA] hydrogels and analyzed the resulting products. N, N'-Methylenebisacrylamide was employed as a cross-linker, ammonium persulfate as an initiator, and N,N'-isopropyl acrylamide and sodium acrylamide as monomers. Structural analysis was measured by using FT-IR. Indeed, SEM analysis was used to characterize the morphological structure of the hydrogel. Studies on swelling were also done. The Taguchi approach was used to study and assess the adsorption studies of the hydrogels for the efficient removal of malachite green and methyl orange. For the optimization, a central composite surface methodology was applied. The effect of several parameters, including adsorbent dosage, pH, initial dye concentration, temperature, time, and mixing speed, was examined using the Taguchi technique, and the primary factors were chosen and examined using the central composite surface methodology. It was discovered that MG dye's (cationic) removal efficiency was higher than that of MO dye's (anionic). The results suggest that [PNIPAM-co-PSA] hydrogel can be used as an effective, alternative and promising adsorbent to be applied in the treatment of effluents containing the cationic dyes from wastewater. The synthesis of hydrogels provides a suitable recyclability platform for the adsorption of cationic dyes and allows for their recovery without the use of powerful reagents.

18.
Eur Phys J E Soft Matter ; 46(4): 23, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36995479

RESUMO

In this study, polyurethane (PU)-based xerogels were synthesized by using the biobased polyol derived from chaulmoogra seed oil. These polyol was used for the preparation of PU xerogels using methylene diphenyl diisocyanate hard segment and polyethylene glycol (PEG6000) as soft segment with 1,4-diazabicyclo[2, 2, 2]octane as catalyst. Tetrahydrofuran, acetonitrile and dimethyl sulfoxide were used as the solvents. Nanocellulose (5 wt %) prepared from bagasse were added as filler, and the obtained composite xerogels were evaluated for chemical stability. The prepared samples were also characterized by using SEM and FTIR. Waste sugarcane bagasse nanocellulose proved as a cheap reinforcer in the xerogel synthesis and for the adsorption of Rhodamine-B dye from the aqueous solution. The factors that affect the adsorption process have been studied including the quantity of the adsorbent (0.02-0.06 g), pH (6-12), temperature (30-50) and time (30-90). Central composite design for four variables and three levels with response surface methodology has been used to get second-order polynomial equation for the percentage dye removal. RSM was confirmed by the measurement of analysis of variance. Increase in the pH and quantity of the adsorbent was found to increase the sorption capacities of the xerogel (NC-PUXe) towards rhodamine B, maximum adsorption.

19.
Eur Phys J E Soft Matter ; 46(3): 21, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36971876

RESUMO

PA-KNNT-P(VDF-HFP) composite films were synthesized using facile solution casting technique. Due to their wide range of applications in dielectric and electrical systems, phosphonic acid (PA)-modified tantalum-doped potassium sodium niobate (KNNT)-polyvinylidene fluoride co-hexafluoropropylene P(VDF-HFP) composite films have piqued the interest of academic researchers. Microstructural analysis showed that PA layers incorporated onto the KNNT particles within the polymer matrix. The PA-KNNT-P(VDF-HFP) composite exhibited improved dielectric and electrical performance over a broad range of frequency, and the value of the dielectric constant of the P(VDF-HFP) composites is improved by ≈119 over the P(VDF-HFP) matrix at a filler loading 19 wt.%. Moreover, PA-KNNT-P(VDF-HFP) composite also reveals higher dielectric constant (≈ 119) and AC conductivity than P(VDF-HFP)-KNNT composites, while maintaining suppressed dielectric loss ([Formula: see text] at 102 Hz). It is also observed that the PA-KNNT-P(VDF-HFP) composite exhibited an insulator-conductor transition with a percolation threshold of fKNNT = 13.4 wt.%. As a result of their exceptional dielectric and electrical characteristics, PA-KNNT-P(VDF-HFP) composites have the potential to find exciting practical applications in a variety of electronic domains.

20.
Nanotechnology ; 34(23)2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36807991

RESUMO

Globally, wastes from agricultural and industrial activities cause water pollution. Pollutants such as microbes, pesticides, and heavy metals in contaminated water bodies beyond their threshold limits result in several diseases like mutagenicity, cancer, gastrointestinal problems, and skin or dermal issues when bioaccumulated via ingestion and dermal contacts. Several technologies have been used in modern times to treat wastes or pollutants such as membrane purification technologies and ionic exchange methods. However, these methods have been recounted to be capital intensive, non-eco-friendly, and need deep technical know-how to operate thus, contributing to their inefficiencies and non-efficacies. This review work evaluated the application of Nanofibrils-protein for the purification of contaminated water. Findings from the study indicated that Nanofibrils protein is economically viable, green, and sustainable when used for water pollutant management or removal because they have outstanding recyclability of wastes without resulting in a secondary phase-pollutant. It is recommended to use residues from dairy industries, agriculture, cattle guano, and wastes from a kitchen in conjunction with nanomaterials to develop nanofibrils protein which has been recounted for the effective removal of micro and micropollutants from wastewater and water. The commercialization of nanofibrils protein for the purification of wastewater and water against pollutants has been tied to novel methods in nanoengineering technology, which depends strongly on the environmental impact in the aqueous ecosystem. So, there is a need to establish a legal framework for the establishment of a nano-based material for the effective purification of water against pollutants.


Assuntos
Química Verde , Nanotecnologia , Poluição da Água , Purificação da Água , Proteínas/química , Águas Residuárias , Purificação da Água/métodos , Química Verde/métodos , Nanofibras/química , Hidrogéis/química
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