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1.
Int J Biol Macromol ; : 133200, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38942673

RESUMO

Controlled drug delivery systems offer numerous advantages. This research evaluates Opuntia leaf mucilage grafted with polyacrylamide (OPM-g-PAM) as a promising controlled-release polymer. PAM chains were grafted onto the backbone of OPM using a microwave-assisted method. Optimization of the best grade was based on % grafting efficiency and intrinsic viscosity, followed by extensive physical and analytical characterizations. Analytical characterizations revealed semicrystalline nature of the biomaterial. SEM and AFM observations revealed rough and porous surfaces, indicating effective grafting. Swelling behavior showed maximum sensitivity at pH 7, with reduced swelling at higher sodium chloride concentrations. A comparative study of % drug release of Rosuvastatin over 24 h showed that the optimized grade controlled drug release effectively, achieving 78.5 % release compared to 98.8 % for GF-3. The release data fitted the Korsmeyer-Peppas model, with an "n" value of 0.8334, indicating non-Fickian (anomalous) diffusion. Bacterial biodegradability studies confirmed the high biodegradability of the graft copolymer. In vitro acute toxicity tests showed no toxicity, as confirmed by histopathological studies of heart, liver, and kidney. Overall, the results indicate that OPM-g-PAM is a highly promising material for use in drug delivery systems, demonstrating potential as a novel controlled-release polymer.

2.
ACS Omega ; 9(3): 3373-3383, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38284044

RESUMO

In this study, the interaction between the neurotransmitter epinephrine and small gold nanoclusters (AunNCs) with n = 6, 8, and 10 is described by density functional theory calculations. The interaction of Au6, Au8, and Au10 nanoclusters with epinephrine is governed by Au-X (X = N and O) anchoring bonding and Au···H-X conventional hydrogen bonding. The interaction mechanism of epinephrine with gold nanoclusters is investigated in terms of electronic energy and geometrical properties. The adsorption energy values for the most favorable configurations of Au6NC@epinephrine, Au8NC@epinephrine, and Au10NC@epinephrine were calculated to be -17.45, -17.86, and -16.07 kcal/mol, respectively, in the gas phase. The results indicate a significant interaction of epinephrine with AunNCs and point to the application of the biomolecular complex AunNC@epinephrine in the fields of biosensing, drug delivery, bioimaging, and other applications. In addition, some important electronic properties, namely, the energy gap between HOMO and LUMO, the Fermi level, and the work function, were computed. The effect of aqueous media on adsorption energy and electronic parameters for the most favorable configurations was also studied to explore the influence of physical biological conditions.

3.
Sci Rep ; 13(1): 20200, 2023 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-37980377

RESUMO

The interaction of tyramine neurotransmitter with silver nano-particle (Ag6) cluster is explored in terms of the molecular structure, electronic properties and NBO analysis of tyramine-AgNPs bio-molecular conjugate. The adsorption mechanism of tyramine onto the Ag6 cluster has been investigated through computing of the electronic and geometrical properties in addition to the adsorption energies in various possible configurations. The magnitude of adsorption energy corresponding to the most favorable tyramine-Ag6 bio-molecular conjugate has been computed to be - 14.36 kcal/mol in the gas phase, which infers a good adsorption of tyramine with AgNPs cluster suggesting the practical applications of tyramine-AgNPs bio-molecular conjugates in bio-sensing, drug delivery, bio-imaging and other applications. Different electronic properties such as the energy gap of HOMO-LUMO, Fermi level and work function have been investigated in detail. Moreover, the effect of aqueous media on adsorption energy and electronic properties of the most favorable tyramine-AgNPs bio-molecular conjugate is investigated in order to understand the impact of the real biological situation.


Assuntos
Tiramina , Água , Estrutura Molecular , Adsorção , Prata/química
4.
Artigo em Inglês | MEDLINE | ID: mdl-37872339

RESUMO

The usage of graphene-based materials (GMs) as energy storage is incredibly popular. Significant obstacles now exist in the way of the generation, storage and consumption of sustainable energy. A primary focus in the work being done to advance environmentally friendly energy technology is the development of effective energy storage materials. Due to their distinct two-dimensional structure and intrinsic physical qualities like good electrical conductivity and wide area, graphene-based materials have a significant potential to be used in energy storage devices. Graphene and GMs have been employed extensively for this due to their special mechanical, thermal, catalytic and other functional qualities. In this review, we covered the topic of employing GMs to store hydrogen for green energy.

5.
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.

6.
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
7.
Artigo em Inglês | MEDLINE | ID: mdl-36857000

RESUMO

The lightweight, low-density, and low-cost natural polymers like cellulose, chitosan, and silk have good chemical and biodegradable properties due to their individually unique structural and functional elements. However, the mechanical properties of these polymers differ from each other. In this scenario, chitosan lacks good mechanical properties than cellulose and silk. The synthesis of nano natural polymer and reinforcement with suitable chemical compounds as the development of nanocomposite gives them promising multidisciplinary applications. Many kinds of research are already published with innovative bio-derived polymeric functional materials (Bd-PFM) applications. Most research interest is carried out on health concerns. Lots of attention has been paid to biomedical applications of Bd-PFM as biosensors. This review aims to provide a glimpse of the nanostructures Bd-PFM biosensors.

8.
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.

9.
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.

10.
ACS Omega ; 8(5): 4436-4452, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36777592

RESUMO

For field-like environmental gas monitoring and noninvasive illness diagnostics, effective sensing materials with exceptional sensing capabilities of sensitive, quick detection of volatile organic compounds (VOCs) are required. Carbon-based nanomaterials (CNMs), like CNTs, graphene, carbon dots (Cdots), and others, have recently drawn a lot of interest for their future application as an elevated-performance sensor for the detection of VOCs. CNMs have a greater potential for developing selective sensors that target VOCs due to their tunable chemical and surface properties. Additionally, the mechanical versatility of CNMs enables the development of novel gas sensors and places them ahead of other sensing materials for wearable applications. An overview of the latest advancements in the study of CNM-based sensors is given in this comprehensive organized review.

11.
Environ Sci Pollut Res Int ; 29(51): 76626-76643, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36168009

RESUMO

Pollution of water is currently a significant worry for scientific communities all over the world, and it is imperative that this problem be solved as quickly as possible. It is today recognized to be one of the most important foci of research worldwide. The present dilemma of clean, fresh waste is being addressed by the subsequent ejection of impurities from polluted water following recycling. There are several effective solutions that have been promoted as a solution to this problem. Even if the present procedures for wastewater treatment degrade a wide variety of effluents efficiently, these protocols still have some kind of restrictions. The most cutting-edge research in this area is being done on the subject of nanotechnology, which has an astounding number of potential uses, one of which is the treatment of wastewater. One of the value-added alternatives utilized for water purification by eliminating the many types of pollutants found in wastewater is the green synthesis of nanocomposites in adsorbents, magnetic separation, photocatalysts, and other similar processes. Within the scope of this study, the most significant discoveries of nanocomposites to date that have been made towards the remediation of wastewater are highlighted.


Assuntos
Poluentes Ambientais , Nanocompostos , Poluentes Químicos da Água , Purificação da Água , Águas Residuárias , Adsorção , Purificação da Água/métodos , Água
12.
Langmuir ; 35(26): 8829-8839, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31177783

RESUMO

Metal-phenolic networks (MPNs) have recently attracted great interest in material chemistry and biomaterials because of their biocompatible, versatile, and multifunctional properties. In this paper, we describe a facile method for preparation of a designable antifouling, antimicrobial, and substrate-independent coating assembled from the coordination of metal ions and catecholic groups. Hydrophilic and catecholic polymers were synthesized by copolymerization of dopamine methacrylamide (DMA) and poly(ethylene glycol)methyl methacrylate (PEGMA) to afford p(PEGMA- co-DMA). To investigate the assembly and formation of MPN films, two different metal ions, that is, ferrous (FeII) and ferric (FeIII) ions, to react with p(PEGMA- co-DMA) were compared. The binding constants between iron ions and p(PEGMA- co-DMA) have been investigated by ultraviolet-visible spectroscopy (UV-vis). Measurements with atomic force microscopy, contact angle goniometer, and X-ray photoelectron spectroscopy (XPS) were carried out to quantitatively analyze the surface morphology, wettability, and interfacial elemental compositions of coatings, respectively. Moreover, ellipsometric measurements were performed to obtain the film thickness and grafting density. In addition, the pH-responsive property of the MPN films was investigated at different pH values, showing fast disassembly of the networks at low pH. The antifouling properties of the obtained coatings were analyzed by exposing them to bacteria of Escherichia coli and Staphylococcus epidermidis and NIH-3T3 fibroblasts under observation of fluorescence microscopy and cell imaging analysis. The findings suggest that the MPN from complexation of p(PEGMA- co-DMA) and metal ions provides excellent antifouling, pH-responsive, and biocompatible properties on a wide range of substrates. Furthermore, the released iron ions can effectively suppress the growth of bacteria. Accordingly, the new coating architecture offers a universal feature to control surface properties and functionalization for various applications.


Assuntos
Antibacterianos/farmacologia , Incrustação Biológica/prevenção & controle , Materiais Revestidos Biocompatíveis/farmacologia , Compostos Férricos/farmacologia , Fenóis/farmacologia , Animais , Antibacterianos/síntese química , Antibacterianos/química , Materiais Revestidos Biocompatíveis/síntese química , Materiais Revestidos Biocompatíveis/química , Escherichia coli/efeitos dos fármacos , Compostos Férricos/química , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Testes de Sensibilidade Microbiana , Microscopia de Fluorescência , Estrutura Molecular , Células NIH 3T3 , Imagem Óptica , Tamanho da Partícula , Fenóis/química , Staphylococcus epidermidis/efeitos dos fármacos , Propriedades de Superfície
13.
Artigo em Inglês | MEDLINE | ID: mdl-22336049

RESUMO

Development of reliable and eco-friendly process for the synthesis of metallic nanoparticles is an important step in the field of application of nanotechnology. We have developed modern method by using agriculture waste to synthesize silver nanoparticles by employing an aqueous peel extract of Annona squamosa in AgNO(3). Controlled growth of silver nanoparticles was formed in 4h at room temperature (25°C) and 60°C. AgNPs were irregular spherical in shape and the average particle size was about 35±5 nm and it is consistent with particle size obtained by XRD Scherer equation.


Assuntos
Annona/química , Resíduos Industriais , Nanopartículas Metálicas/química , Extratos Vegetais/metabolismo , Folhas de Planta/química , Prata/química , Cromatografia Gasosa-Espectrometria de Massas , Microscopia Eletrônica de Transmissão , Nanotecnologia , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
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