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1.
Sensors (Basel) ; 22(11)2022 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-35684745

RESUMO

The sensing characteristics of toluene gas are monitored by fabricating ZnO nanorod structures. ZnO nanostructured sensor materials are produced on a Zn film via an ultrasonic process in a 0.01 M aqueous solution of C6H12N4 and Zn(NO3)2∙6H2O. The response of the sensors subjected to heat treatment in oxygen and nitrogen atmospheres is improved by 20% and 10%, respectively. The improvement is considered to be correlated with the increase in grain size. The relationship between the heat treatment and sensing characteristics is evaluated.


Assuntos
Nanoestruturas , Nanotubos , Óxido de Zinco , Temperatura Alta , Nanoestruturas/química , Nanotubos/química , Tolueno , Óxido de Zinco/química
2.
Anal Chim Acta ; 1215: 339974, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35680337

RESUMO

The accumulation of pesticide residues may cause harm to the human body and the environment. Traditional chromatographic methods are limited by stringent testing conditions, so it is necessary to develop convenient and efficient methods for pesticide residue detection. Fluorescence assays have great potential in the development of portable detection tools due to their fast response and intuitive visualization. In this paper, we reviewed nanomaterial-based fluorescent probes for pesticide residue detection that have been reported in recent years, including small molecule probes, metal-organic framework fluorescent probes, fluorescent quantum dot probes, and nanocluster probes. In addition, we describe the design strategy, detection mechanism, and practical application of these probes in detail. The latest progress and application strategies of fluorescent probe detection methods based on nanomaterials are comprehensively discussed, and prospects are proposed.


Assuntos
Nanoestruturas , Resíduos de Praguicidas , Pontos Quânticos , Corantes Fluorescentes/química , Humanos , Resíduos de Praguicidas/análise
3.
Int J Mol Sci ; 23(11)2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35682931

RESUMO

Climate change and increasing contamination of the environment, due to anthropogenic activities, are accompanied with a growing negative impact on human life. Nowadays, humanity is threatened by the increasing incidence of difficult-to-treat cancer and various infectious diseases caused by resistant pathogens, but, on the other hand, ensuring sufficient safe food for balanced human nutrition is threatened by a growing infestation of agriculturally important plants, by various pathogens or by the deteriorating condition of agricultural land. One way to deal with all these undesirable facts is to try to develop technologies and sophisticated materials that could help overcome these negative effects/gloomy prospects. One possibility is to try to use nanotechnology and, within this broad field, to focus also on the study of two-dimensional carbon-based nanomaterials, which have excellent prospects to be used in various economic sectors. In this brief up-to-date overview, attention is paid to recent applications of graphene-based nanomaterials, i.e., graphene, graphene quantum dots, graphene oxide, graphene oxide quantum dots, and reduced graphene oxide. These materials and their various modifications and combinations with other compounds are discussed, regarding their biomedical and agro-ecological applications, i.e., as materials investigated for their antineoplastic and anti-invasive effects, for their effects against various plant pathogens, and as carriers of bioactive agents (drugs, pesticides, fertilizers) as well as materials suitable to be used in theranostics. The negative effects of graphene-based nanomaterials on living organisms, including their mode of action, are analyzed as well.


Assuntos
Grafite , Nanoestruturas , Pontos Quânticos , Carbono , Humanos , Nanotecnologia , Pontos Quânticos/uso terapêutico
4.
Int J Mol Sci ; 23(11)2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35683010

RESUMO

The advancing field of nanoscience has produced lower mass, smaller size, and expanded chemical composition nanoparticles over recent years. These new nanoparticles have challenged traditional analytical methods of qualification and quantification. Such advancements in nanoparticles and nanomaterials have captured the attention of toxicologists with concerns regarding the environment and human health impacts. Given that nanoparticles are only limited by size (1-100 nm), their chemical and physical characteristics can drastically change and thus alter their overall nanotoxicity in unpredictable ways. A significant limitation to the development of nanomaterials is that traditional regulatory and scientific methods used to assess the biological and environmental toxicity of chemicals do not generally apply to the assessment of nanomaterials. Significant research effort has been initiated, but much more is still needed to develop new and improved analytical measurement methods for detecting and quantitating nanomaterials in biological and environmental systems.


Assuntos
Nanopartículas , Nanoestruturas , Humanos , Nanopartículas/química , Nanoestruturas/química
5.
Nutrients ; 14(11)2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35684016

RESUMO

The extensive applications of nanomaterials have increased their toxicities to human health. As a commonly recommended health care product, vitamins have been reported to exert protective roles against nanomaterial-induced oxidative stress and inflammatory responses. However, there have been some controversial conclusions in regards to this field of research. This meta-analysis aimed to comprehensively evaluate the roles and mechanisms of vitamins for cells and animals exposed to nanomaterials. Nineteen studies (seven in vitro, eleven in vivo and one in both) were enrolled by searching PubMed, EMBASE, and Cochrane Library databases. STATA 15.0 software analysis showed vitamin E treatment could significantly decrease the levels of oxidants [reactive oxygen species (ROS), total oxidant status (TOS), malondialdehyde (MDA)], increase anti-oxidant glutathione peroxidase (GPx), suppress inflammatory mediators (tumor necrosis factor-α, interleukin-6, C-reactive protein, IgE), improve cytotoxicity (manifested by an increase in cell viability and a decrease in pro-apoptotic caspase-3 activity), and genotoxicity (represented by a reduction in the tail length). These results were less changed after subgroup analyses. Pooled analysis of in vitro studies indicated vitamin C increased cell viability and decreased ROS levels, but its anti-oxidant potential was not observed in the meta-analysis of in vivo studies. Vitamin A could decrease MDA, TOS and increase GPx, but its effects on these indicators were weaker than vitamin E. Also, the combination of vitamin A with vitamin E did not provide greater anti-oxidant effects than vitamin E alone. In summary, we suggest vitamin E alone supplementation may be a cost-effective option to prevent nanomaterial-induced injuries.


Assuntos
Antioxidantes , Nanoestruturas , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Suplementos Nutricionais , Glutationa Peroxidase/metabolismo , Inflamação/metabolismo , Inflamação/prevenção & controle , Nanoestruturas/toxicidade , Oxidantes/farmacologia , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Vitamina A/metabolismo , Vitamina E/farmacologia , Vitaminas/farmacologia
6.
Methods Mol Biol ; 2487: 93-112, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35687231

RESUMO

Multienzyme reactions play an important role in cellular metabolic functions. The assembly of a metabolon is often observed, in which the position and the orientation of composite enzymes are optimized to facilitate the substrate transport. The recent progress of DNA nanotechnology is promising to organize the assembly of bimolecular complexes with precise controlled geometric patterns at nanoscale, such as enzyme cascades assembly, biomimetic substrate channeling, and compartmentalization. Here, we present detailed protocols of using DNA nanoscaffolds to assemble a multienzyme system with control over spatial interactions and arrangements of individual components. The protocols include the preparation and purification of DNA nanostructures, the bioconjugation of DNA with proteins and cofactors, the chromatography purification of DNA-conjugated biomolecules, the characterization of assemblies by routine gel electrophoresis and advanced AFM imaging, as well as the activity evaluation of multienzyme assemblies.


Assuntos
DNA , Nanoestruturas , Biomimética , DNA/química , Nanoestruturas/química , Nanotecnologia/métodos , Proteínas
7.
Methods Mol Biol ; 2487: 177-187, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35687236

RESUMO

Self-assembly is a phenomenon that governs molecular structural organization in nature, therefore raising research interest for the fabrication of novel nanomaterials with diverse applications in biocatalysis, biomedicine, material templating, and biosensor development. In this chapter we provide protocols for the development of supramolecular protein complexes based on host-guest interactions in the presence of the macrocyclic host, cucurbit[8]uril (CB[8]). CB[8] is reported to exhibit high binding affinity towards the tripeptide Phe-Gly-Gly (FGG), therefore it can be utilized as a selective adhesive of protein molecules, after fusion of FGG to an accessible protein surface.


Assuntos
Hidrocarbonetos Aromáticos com Pontes , Nanoestruturas , Compostos Heterocíclicos com 2 Anéis , Imidazóis/química , Imidazolidinas , Compostos Macrocíclicos , Nanoestruturas/química , Proteínas/química
8.
Methods Mol Biol ; 2487: 197-204, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35687238

RESUMO

Multienzyme complexes naturally exist in cells to catalyze cascade reactions in metabolic pathways. By clustering the enzymes in close proximity, these nanomachineries achieve effective conversion of metabolites. Bioengineers are working on the development of synthetic versions of multienzyme complexes in cells to synergize heterologous biosynthesis. Assembling enzymes on protein scaffolds through protein-protein interactions is a viable and facile way to form synthetic multienzyme complexes. Here, we describe the general methods to construct self-assembled multienzyme nanostructures in Escherichia coli for biosynthesis of valuable chemicals.


Assuntos
Nanoestruturas , Biocatálise , Catálise , Escherichia coli/genética , Escherichia coli/metabolismo , Complexos Multienzimáticos/química , Nanoestruturas/química , Proteínas/química
9.
Nat Chem ; 14(6): 600-613, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35668213

RESUMO

DNA nanotechnology has emerged as a powerful tool to precisely design and control molecular circuits, machines and nanostructures. A major goal in this field is to build devices with life-like properties, such as directional motion, transport, communication and adaptation. Here we provide an overview of the nascent field of dissipative DNA nanotechnology, which aims at developing life-like systems by combining programmable nucleic-acid reactions with energy-dissipating processes. We first delineate the notions, terminology and characteristic features of dissipative DNA-based systems and then we survey DNA-based circuits, devices and materials whose functions are controlled by chemical fuels. We emphasize how energy consumption enables these systems to perform work and cyclical tasks, in contrast with DNA devices that operate without dissipative processes. The ability to take advantage of chemical fuel molecules brings dissipative DNA systems closer to the active molecular devices that exist in nature.


Assuntos
Nanoestruturas , Nanotecnologia , DNA/química , Nanoestruturas/química
10.
J Nanobiotechnology ; 20(1): 262, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672712

RESUMO

Interest in nanomaterials and especially nanoparticles has exploded in the past decades primarily due to their novel or enhanced physical and chemical properties compared to bulk material. These extraordinary properties have created a multitude of innovative applications in the fields of medicine and pharma, electronics, agriculture, chemical catalysis, food industry, and many others. More recently, nanoparticles are also being synthesized 'biologically' through the use of plant- or microorganism-mediated processes, as an environmentally friendly alternative to the expensive, energy-intensive, and potentially toxic physical and chemical synthesis methods. This transdisciplinary approach to nanoparticle synthesis requires that biologists and biotechnologists understand and learn to use the complex methodology needed to properly characterize these processes. This review targets a bio-oriented audience and summarizes the physico-chemical properties of nanoparticles, and methods used for their characterization. It highlights why nanomaterials are different compared to micro- or bulk materials. We try to provide a comprehensive overview of the different classes of nanoparticles and their novel or enhanced physicochemical properties including mechanical, thermal, magnetic, electronic, optical, and catalytic properties. A comprehensive list of the common methods and techniques used for the characterization and analysis of these properties is presented together with a large list of examples for biogenic nanoparticles that have been previously synthesized and characterized, including their application in the fields of medicine, electronics, agriculture, and food production. We hope that this makes the many different methods more accessible to the readers, and to help with identifying the proper methodology for any given nanoscience problem.


Assuntos
Nanopartículas , Nanoestruturas , Agricultura , Catálise , Nanopartículas/química , Nanoestruturas/química , Plantas/química
11.
J Nanobiotechnology ; 20(1): 265, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672765

RESUMO

Overproduced reactive oxygen and reactive nitrogen species (RONS) in the brain are involved in the pathogenesis of several neurological diseases, such as Alzheimer's disease, Parkinson's disease, traumatic brain injury, and stroke, as they attack neurons and glial cells, triggering cellular redox stress. Neutralizing RONS, and, thus, alleviating redox stress, can slow down or stop the progression of neurological diseases. Currently, an increasing number of studies are applying nanomaterials (NMs) with anti-redox activity and exploring the potential mechanisms involved in redox stress-related neurological diseases. In this review, we summarize the anti-redox mechanisms of NMs, including mimicking natural oxidoreductase activity and inhibiting RONS generation at the source. In addition, we propose several strategies to enhance the anti-redox ability of NMs and highlight the challenges that need to be resolved in their application. In-depth knowledge of the mechanisms and potential application of NMs in alleviating redox stress will help in the exploration of the therapeutic potential of anti-redox stress NMs in neurological diseases.


Assuntos
Nanoestruturas , Espécies Reativas de Nitrogênio , Antioxidantes/uso terapêutico , Oxirredução , Estresse Oxidativo , Espécies Reativas de Oxigênio
12.
J Nanobiotechnology ; 20(1): 257, 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35658974

RESUMO

Self-assembled photonic systems with well-organized spatial arrangement and engineered optical properties can be used as efficient energy materials and as effective biomedical agents. The lessons learned from natural light-harvesting antennas have inspired the design and synthesis of a series of biomimetic photonic complexes, including those containing strongly coupled dye aggregates with dense molecular packing and unique spectroscopic features. These photoactive components provide excellent features that could be coupled to multiple applications including light-harvesting, energy transfer, biosensing, bioimaging, and cancer therapy. Meanwhile, nanoscale DNA assemblies have been employed as programmable and addressable templates to guide the formation of DNA-directed multi-pigment complexes, which can be used to enhance the complexity and precision of artificial photonic systems and show the potential for energy and biomedical applications. This review focuses on the interface of DNA nanotechnology and biomimetic photonic systems. We summarized the recent progress in the design, synthesis, and applications of bioinspired photonic systems, highlighted the advantages of the utilization of DNA nanostructures, and discussed the challenges and opportunities they provide.


Assuntos
Biomimética , Nanoestruturas , DNA/química , Nanoestruturas/química , Nanotecnologia/métodos , Óptica e Fotônica
13.
PLoS One ; 17(6): e0269086, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35653411

RESUMO

Four types of flowerlike manganese dioxide in nano scale was synthesized via a liquid phase method in KMnO4-H2SO4 solution and Cu particles, wherein the effect of Cu particles was investigated in detail. The obtained manganese dioxide powder was characterized by XRD, SEM and TEM, and the supercapacity properties of MnO2 electrode materials were measured. The results showed that doping carbon black can benefit to better dispersion of copper particles, resulting in generated smaller size of Cu particles, and the morphology of MnO2 nanoparticles was dominated by that of Cu particles. The study of MnO2 synthesis by different sources of Cu particles showed that the size of MnO2 particles decreased significantly with freshly prepared fine copper powder compared with using commercial Cu powder, and the size of MnO2 particles can be further reduced to 120 nm by prepared Cu particles with smaller size. Therefore, it was suggested that the copper particles served as not only the reductant and but also the nuclei centre for the growth of MnO2 particles in synthesis process MnO2, and that is the reason how copper particles worked on the growth of flower-like MnO2 and electrochemical property. In the part of investigation for electrochemical property, the calculated results of b values indicated that the electrode materials have pseudo capacitance property, and the highest specific capacitance of 197.2 F g-1 at 2 mV s-1 and 148 F/g at 1 A/g were obtained for MCE electrode materials (MnO2 was synthesized with freshly prepared copper particles, where carbon black was used and dispersed in ethanol before preparation of Cu particles). The values of charge transfer resistance in all types of MnO2 materials electrodes were smaller than 0.08 Ω. The cycling retention of MCE material electrode is still kept as 93.8% after 1000 cycles.


Assuntos
Compostos de Manganês , Nanoestruturas , Cobre , Compostos de Manganês/química , Óxidos/química , Pós , Fuligem
14.
Proc Natl Acad Sci U S A ; 119(23): e2200363119, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35653569

RESUMO

SignificanceThis study analyzed the dynamic protein corona on the surface of nanoparticles as they traversed from blood to cell lysosomes and escaped from lysosomes to cytoplasm in the target cells. We found with proteomic analysis an abundance of chaperone and glycolysis coronal proteins (i.e., heat shock cognate protein 70, heat shock protein 90, and pyruvate kinase M2 [PKM2]) after escape of the nanoparticles from lysosomes to the cytosol. Alterations of the coronal proteins (e.g., PKM2 and chaperone binding) induced proteostasis collapse, which subsequently led to elevated chaperone-mediated autophagy (CMA) activity in cells. As PKM2 is a key molecule in cell metabolism, we also revealed that PKM2 depletion was causative to CMA-induced cell metabolism disruption from glycolysis to lipid metabolism.


Assuntos
Nanoestruturas , Coroa de Proteína , Coroa de Proteína/metabolismo , Proteômica , Proteostase , Piruvato Quinase/metabolismo
15.
Inorg Chem ; 61(24): 9328-9338, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35666261

RESUMO

Two-dimensional (2D) metal-organic framework (MOF) nanosheets have been demonstrated to be promising templates for the growth of various kinds of nanomaterials on their surfaces to construct novel 2D composites, thus realizing enhanced performance in various applications. Herein, we report the growth of Cu2O nanoparticles on 2D Zr-ferrocene (Zr-Fc)-MOF (Zr-Fc-MOF) nanosheets to prepare 2D composites for near-infrared (NIR) photothermally enhanced chemodynamic antibacterial therapy. The uniform Zr-Fc-MOF nanosheets are synthesized using the solvothermal method, followed by ultrasound sonication, and Cu2O nanoparticles are then deposited on its surface to obtain the Cu2O-decorated Zr-Fc-MOF (denoted as Cu2O/Zr-Fc-MOF) 2D composite. Promisingly, the Cu2O/Zr-Fc-MOF composite shows higher chemodynamic activity for producing ·OH via Fenton-like reaction than that of the pristine Zr-Fc-MOF nanosheets. More importantly, the chemodynamic activity of the Cu2O/Zr-Fc-MOF composite can be further enhanced by the photothermal effect though NIR laser (808 nm) irradiation. Thus, the Cu2O/Zr-Fc-MOF composite can be used as an efficient nanoagent for photothermally enhanced chemodynamic antibacterial therapy.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Nanoestruturas , Antibacterianos/farmacologia , Estruturas Metalorgânicas/farmacologia , Metalocenos/farmacologia
16.
Talanta ; 247: 123553, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35688100

RESUMO

Fast and quantitative detection of dopamine (DA) is highly desirable but still challenging in the clinical diagnosis due to the complexity of the biological samples. Herein, a novel peony-like 3D-MoS2/Graphene (peony-like 3D-MoS2/GR) nanomaterial is designed and characterized. The nanomaterial exhibits outstanding the peroxidase-like activity, which can be employed as a nanozyme for facile and fast colorimetric determination of dopamine. The peony-like 3D-MoS2/GR-based colorimetric assay presents a wide liner dependence on the DA concentration in the range of 1-400 µM and a low detection limit of 0.21 µM. Such excellent results originate from its unique structure, which offers abundant active sites, high specific surface area, interconnected network and the special microenvironment. Furthermore, this reported colorimetric assay is successfully employed for detection of DA in human serum and urine samples. The recovery percentage ranges from 98 to 105.6%. Hence, the peony-like 3D-MoS2/GR paves a new avenue for detection of DA in real biological systems.


Assuntos
Grafite , Nanoestruturas , Paeonia , Colorimetria/métodos , Corantes/química , Dissulfetos/química , Dopamina , Grafite/química , Humanos , Peróxido de Hidrogênio/química , Molibdênio/química , Nanoestruturas/química , Oxirredutases , Peroxidase/química , Peroxidases
17.
Microb Cell Fact ; 21(1): 118, 2022 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-35717207

RESUMO

Microbial infection and cancer are two leading causes of global mortality. Discovering and developing new therapeutics with better specificity having minimal side-effects and no drug resistance are of an immense need. In this regard, cationic antimicrobial peptides (AMP) with dual antimicrobial and anticancer activities are the ultimate choice. For better efficacy and improved stability, the AMPs available for treatment still required to be modified. There are several strategies in which AMPs can be enhanced through, for instance, nano-carrier application with high selectivity and specificity enables researchers to estimate the rate of drug delivery to a particular tissue. In this review we present the biology and modes of action of AMPs for both anticancer and antimicrobial activities as well as some modification strategies to improve the efficacy and selectivity of these AMPs.


Assuntos
Anti-Infecciosos , Nanoestruturas , Neoplasias , Antibacterianos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Bactérias , Nanoestruturas/química , Neoplasias/tratamento farmacológico
18.
J Am Chem Soc ; 144(23): 10495-10506, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35679484

RESUMO

Patterning functional inorganic nanomaterials is an important process for advanced manufacturing of quantum dot (QD) electronic and optoelectronic devices. This is typically achieved by inkjet printing, microcontact printing, and photo- and e-beam lithography. Here, we investigate a different patterning approach that utilizes local heating, which can be generated by various sources, such as UV-, visible-, and IR-illumination, or by proximity heat transfer. This direct thermal lithography method, termed here heat-induced patterning of inorganic nanomaterials (HIPIN), uses colloidal nanomaterials with thermally unstable surface ligands. We designed several families of such ligands and investigated their chemical and physical transformations responsible for heat-induced changes of nanocrystal solubility. Compared to traditional photolithography using photochemical surface reactions, HIPIN extends the scope of direct optical lithography toward longer wavelengths of visible (532 nm) and infrared (10.6 µm) radiation, which is necessary for patterning optically thick layers (e.g., 1.2 µm) of light-absorbing nanomaterials. HIPIN enables patterning of features defined by the diffraction-limited beam size. Our approach can be used for direct patterning of metal, semiconductor, and dielectric nanomaterials. Patterned semiconductor QDs retain the majority of their as-synthesized photoluminescence quantum yield. This work demonstrates the generality of thermal patterning of nanomaterials and provides a new path for additive device manufacturing using diverse colloidal nanoscale building blocks.


Assuntos
Nanoestruturas , Pontos Quânticos , Temperatura Alta , Ligantes , Pontos Quânticos/química , Semicondutores
19.
Annu Rev Chem Biomol Eng ; 13: 167-191, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35700529

RESUMO

Liquid-phase transmission electron microscopy (LPTEM) is a powerful in situ visualization technique for directly characterizing nanomaterials in the liquid state. Despite its successful application in many fields, several challenges remain in achieving more accurate and reliable observations. We present LPTEM in chemical and biological applications, including studies for the morphological transformation and dynamics of nanoparticles, battery systems, catalysis, biomolecules, and organic systems. We describe the possible interactions and effects of the electron beam on specimens during observation and present sample-specific approaches to mitigate and control these electron-beam effects. We provide recent advances in achieving atomic-level resolution for liquid-phase investigation of structures anddynamics. Moreover, we discuss the development of liquid cell platforms and the introduction of machine-learning data processing for quantitative and objective LPTEM analysis.


Assuntos
Nanopartículas , Nanoestruturas , Microscopia Eletrônica de Transmissão , Nanopartículas/química
20.
Sci Rep ; 12(1): 9909, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35701519

RESUMO

The need for a mild, low-cost, green environment that is able to produce exotic properties of output nanostructures is appealing nowadays. Employing these requirements, the copper (Cu)-based oxide nanostructures have been successfully synthesised via one-pot reaction using biocompatible natural polyphenol, tannic acid (TA) as both the reducing agent and stabiliser at 60, 70 and 80 °C. The structural and optical studies disclosed the effect of TA on the surface morphology, phase purity, elemental composition, optical microstrain and optical intrinsic energy of this mixed Cu2O and CuO nanostructures. The optically based method describes the comparative details of the multi-band gap in the presence of more than one element with overlapping spectra from the first-derivative absorbance curve [Formula: see text] and the exponential absorbance of Urbach tail energy [Formula: see text] towards the conventional Tauc bandgap. The [Formula: see text] demonstrates that the pronounced effect of TA that Cu2O and CuO nanostructures creates much sensitive first-derivative bandgap output compared to the Tauc bandgap. The results also show that the [Formula: see text] reduced as the temperature reaches 70 °C and then experienced sudden increase at 80 °C. The change in the pattern is parallel to the trend observed in the Williamson-Hall microstrain and is evident from the variations of the mean crystallite size [Formula: see text] which is also a cause response to the change in temperature or pH. Therefore, the current work has elucidated that the structural and optical correlations on the as-synthesised Cu2O and CuO nanostructures in the presence of TA were the combined reaction of pH change and the ligand complexation reactions. The acquired results suggest a more comprehensive range of studies to further understand the extent relationship between the physical and optical properties of TA functionalised Cu-based oxide nanostructures.


Assuntos
Nanoestruturas , Óxidos , Cobre/química , Nanoestruturas/química , Óxidos/química , Taninos , Temperatura
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