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1.
Molecules ; 26(1)2020 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-33374726

RESUMO

A novel class of quinolinol-based dimeric indium complexes (1-6) was synthesized and characterized using 1H and 13C(1H) NMR spectroscopy and elemental analysis. Compounds 1-6 exhibited typical low-energy absorption bands assignable to quinolinol-centered π-π* charge transfer (CT) transition. The emission spectra of 1-6 exhibited slight bathochromic shifts with increasing solvent polarity (p-xylene < tetrahydrofuran (THF) < dichloromethane (DCM)). The emission bands also showed a gradual redshift, with an increase in the electron-donating effect of substituents at the C5 position of the quinoline groups. The absolute emission quantum yields (ΦPL) of compounds 1 (11.2% in THF and 17.2% in film) and 4 (17.8% in THF and 36.2% in film) with methyl substituents at the C5 position of the quinoline moieties were higher than those of the indium complexes with other substituents.


Assuntos
Índio/química , Processos Fotoquímicos , Teoria Quântica , Ácido Quinolínico/síntese química , Solventes/química , Modelos Moleculares , Estrutura Molecular
2.
Int J Nanomedicine ; 15: 8037-8043, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33116516

RESUMO

Background: Artificial synaptic behaviors are necessary to investigate and implement since they are considered to be a new computing mechanism for the analysis of complex brain information. However, flexible and transparent artificial synapse devices based on thin-film transistors (TFTs) still need further research. Purpose: To study the application of flexible and transparent thin-film transistors with nanometer thickness on artificial synapses. Materials and Methods: Here, we report the design and fabrication of flexible and transparent artificial synapse devices based on TFTs with polyethylene terephthalate (PET) as the flexible substrate, indium tin oxide (ITO) as the gate and a polyvinyl alcohol (PVA) grid insulating layer as the gate insulation layer at room temperature. Results: The charge and discharge of the carriers in the flexible and transparent thin-film transistors with nanometer thickness can be used for artificial synaptic behavior. Conclusion: In summary, flexible and transparent thin-film transistors with nanometer thickness can be used as pressure and temperature sensors. Besides, inherent charge transfer characteristics of indium gallium zinc oxide semiconductors have been employed to study the biological synapse-like behaviors, including synaptic plasticity, excitatory postsynaptic current (EPSC), paired-pulse facilitation (PPF), and long-term memory (LTM). More precisely, the spike rate plasticity (SRDP), one representative synaptic plasticity, has been demonstrated. Such TFTs are interesting for building future neuromorphic systems and provide a possibility to act as fundamental blocks for neuromorphic system applications.


Assuntos
Nanopartículas/química , Nanotecnologia/instrumentação , Transistores Eletrônicos , Eletrodos , Gálio/química , Índio/química , Maleabilidade , Compostos de Estanho/química , Óxido de Zinco/química
3.
Chemosphere ; 258: 127374, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32554021

RESUMO

Photocatalysis is extensively investigated as a green, efficient and promising technique for environmental remediation. In this study, a series of template free In-doped BiOBrxI1-x photocatalysts have been successfully prepared at room temperature and characterized by various methods. Complete degradation of negatively charged methyl Orange, positively charged Rhodamine B and Methylene Blue organic dyes, and neutral and colorless non-dye organic compound of furfural was attained. The flat band potential offered the possibility of reduction of dissolved O2 to O2.- in the conduction band while the trapping experiment identified the (O2.-)is the main radical species followed by h+ for the photodegradation. In-BiOBrI-0.4 had an excellent photocatalytic degradation activity which could be due to the synergetic effect between metal ion doping and solid solution formation. It further promotes visible light-harvesting ability and photoinduced charge carrier separation efficiency. The order of the reaction rate was determined and the mechanism was proposed. This work can lay a base for the design of effective photocatalyst toward environmental remediation.


Assuntos
Bismuto/química , Corantes/análise , Poluentes Ambientais/análise , Recuperação e Remediação Ambiental/métodos , Índio/química , Compostos de Iodo/química , Nanoestruturas/química , Fotólise , Compostos Azo/análise , Catálise , Luz , Azul de Metileno/análise , Rodaminas/análise , Propriedades de Superfície , Temperatura
4.
Nat Commun ; 11(1): 2405, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32415064

RESUMO

Fiber-based electronics enabling lightweight and mechanically flexible/stretchable functions are desirable for numerous e-textile/e-skin optoelectronic applications. These wearable devices require low-cost manufacturing, high reliability, multifunctionality and long-term stability. Here, we report the preparation of representative classes of 3D-inorganic nanofiber network (FN) films by a blow-spinning technique, including semiconducting indium-gallium-zinc oxide (IGZO) and copper oxide, as well as conducting indium-tin oxide and copper metal. Specifically, thin-film transistors based on IGZO FN exhibit negligible performance degradation after one thousand bending cycles and exceptional room-temperature gas sensing performance. Owing to their great stretchability, these metal oxide FNs can be laminated/embedded on/into elastomers, yielding multifunctional single-sensing resistors as well as fully monolithically integrated e-skin devices. These can detect and differentiate multiple stimuli including analytes, light, strain, pressure, temperature, humidity, body movement, and respiratory functions. All of these FN-based devices exhibit excellent sensitivity, response time, and detection limits, making them promising candidates for versatile wearable electronics.


Assuntos
Nanopartículas Metálicas/química , Nanofibras/química , Dispositivos Eletrônicos Vestíveis , Consumo de Bebidas Alcoólicas , Técnicas Biossensoriais , Testes Respiratórios , Cobre/química , Elastômeros , Etanol/análise , Análise de Elementos Finitos , Gálio/química , Humanos , Índio/química , Teste de Materiais , Movimento (Física) , Poliestirenos/química , Semicondutores , Espectrofotometria Ultravioleta , Temperatura , Têxteis , Óxido de Zinco/química
5.
Phys Chem Chem Phys ; 22(22): 12772-12784, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32467952

RESUMO

The present work has been carried out with the aim to design and develop an efficient light harvesting inorganic-organic hybrid nanoscale material by employing a less toxic, environment friendly inorganic substance and also to understand the mechanism of inter-particle electronic interaction between the inorganic and organic components of the nanomaterial. Specifically, the inorganic-organic hybrid associate has been made by integrating water soluble semiconductor (zinc-silver-indium-sulfide (ZAIS)) QDs and organic J-aggregates of a cyanine dye (S2165). The fabrication of the present nano-hybrid system has been achieved via electrostatically driven self-assembly of organic dyes over ZAIS QDs. The interaction between QD and J-aggregates has been investigated by using steady state and time resolved fluorescence measurements. Zeta potential measurements have also been performed to understand the role of electrostatic interaction and thermodynamic feasibility of the association process. The investigations have revealed that the energy transfer (ET) process between QD and J-aggregates was mediated through a dipole-dipole mechanism. Interestingly, data analysis based on Förster theory has further revealed that the ET from QD to J-aggregates is very high, indicating efficient electronic coupling between the inorganic QD and the organic J-aggregates. Zeta potential measurements and thermodynamic calculations have demonstrated that the interaction between QD and organic dye is electrostatically driven and the association of organic dyes over QDs is thermodynamically feasible. The outcome of the present study is expected to be helpful in designing efficient nanoscale light harvesting devices. Additionally, fluorescence microscopy and toxicity studies on the QDs have also shown their suitability for biological applications.


Assuntos
Carbocianinas/química , Corantes Fluorescentes/química , Pontos Quânticos/química , Transferência de Energia , Índio/química , Estrutura Molecular , Tamanho da Partícula , Semicondutores , Prata/química , Solubilidade , Sulfetos/química , Propriedades de Superfície , Água/química , Zinco/química
6.
Inorg Chem ; 59(10): 7238-7251, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32337985

RESUMO

A phosphinate-bearing picolinic acid-based chelating ligand (H6dappa) was synthesized and characterized to assess its potential as a bifunctional chelator (BFC) for inorganic radiopharmaceuticals. Nuclear magnetic resonance (NMR) spectroscopy was employed to investigate the chelator coordination chemistry with a variety of nonradioactive trivalent metal ions (In3+, Lu3+, Y3+, Sc3+, La3+, Bi3+). Density functional theory (DFT) calculations explored the coordination environments of aforementioned metal complexes. The thermodynamic stability of H6dappa with four metal ions (In3+, Lu3+, Y3+, Sc3+) was deeply investigated via potentiometric and spectrophotometric (UV-vis) titrations, employing a combination of acidic in-batch, joint potentiometric/spectrophotometric, and ligand-ligand competition titrations; high stability constants and pM values were calculated for all four metal complexes. Radiolabeling conditions for three clinically relevant radiometal ions were optimized ([111In]In3+, [177Lu]Lu3+, [90Y]Y3+), and the serum stability of [111In][In(dappa)]3- was studied. Through concentration-, time-, temperature-, and pH-dependent labeling experiments, it was determined that H6dappa radiolabels most effectively at near-physiological pH for all radiometal ions. Furthermore, very rapid radiolabeling at ambient temperature was observed, as maximal radiolabeling was achieved in less than 1 min. Molar activities of 29.8 GBq/µmol and 28.2 GBq/µmol were achieved for [111In]In3+ and [177Lu]Lu3+, respectively. For H6dappa, high thermodynamic stability did not correlate with kinetic inertness-lability was observed in serum stability studies, suggesting that its metal complexes might not be suitable as a BFC in radiopharmaceuticals.


Assuntos
Complexos de Coordenação/síntese química , Índio/química , Lutécio/química , Ácidos Fosfínicos/química , Ácidos Picolínicos/química , Ítrio/química , Complexos de Coordenação/química , Estrutura Molecular , Termodinâmica
7.
Int J Nanomedicine ; 15: 1951-1965, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32256071

RESUMO

Introduction: Indium phosphide (InP) quantum dots (QDs) have shown a broad application prospect in the fields of biophotonics and nanomedicine. However, the potential toxicity of InP QDs has not been systematically evaluated. In particular, the effects of different surface modifications on the biodistribution and toxicity of InP QDs are still unknown, which hinders their further developments. The present study aims to investigate the biodistribution and in vivo toxicity of InP/ZnS QDs. Methods: Three kinds of InP/ZnS QDs with different surface modifications, hQDs (QDs-OH), aQDs (QDs-NH2), and cQDs (QDs-COOH) were intravenously injected into BALB/c mice at the dosage of 2.5 mg/kg BW or 25 mg/kg BW, respectively. Biodistribution of three QDs was determined through cryosection fluorescence microscopy and ICP-MS analysis. The subsequent effects of InP/ZnS QDs on histopathology, hematology and blood biochemistry were evaluated at 1, 3, 7, 14 and 28 days post-injection. Results: These types of InP/ZnS QDs were rapidly distributed in the major organs of mice, mainly in the liver and spleen, and lasted for 28 days. No abnormal behavior, weight change or organ index were observed during the whole observation period, except that 2 mice died on Day 1 after 25 mg/kg BW hQDs treatment. The results of H&E staining showed that no obvious histopathological abnormalities were observed in the main organs (including heart, liver, spleen, lung, kidney, and brain) of all mice injected with different surface-functionalized QDs. Low concentration exposure of three QDs hardly caused obvious toxicity, while high concentration exposure of the three QDs could cause some changes in hematological parameters or biochemical parameters related to liver function or cardiac function. More attention needs to be paid on cQDs as high-dose exposure of cQDs induced death, acute inflammatory reaction and slight changes in liver function in mice. Conclusion: The surface modification and exposure dose can influence the biological behavior and in vivo toxicity of QDs. The surface chemistry should be fully considered in the design of InP-based QDs for their biomedical applications.


Assuntos
Pontos Quânticos/toxicidade , Animais , Análise Química do Sangue , Feminino , Índio/química , Camundongos Endogâmicos BALB C , Microscopia de Fluorescência , Fosfinas/química , Pontos Quânticos/química , Sulfetos/química , Propriedades de Superfície , Distribuição Tecidual , Compostos de Zinco/química
8.
Inorg Chem ; 59(7): 5231-5239, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32212684

RESUMO

With the aid of a pyridyl tetracarboxylate ligand, 2,5-bis(2',5'-dicarboxylphenyl)pyridine (H4L), two indium-organic frameworks, [In2(L)(OH)2]·2DMF·2H2O (1) and [Me2NH2][In(L)]·2.5NMF·4H2O (2), with (6,8)- and (4,4)-connected nets have been constructed in different solvent systems. Both 1 and 2 exhibit high thermal and chemical stability. Gas sorption behavior of 1 and 2 for N2, C2H2, C2H4, CO2, and CH4 indicate excellent separation selectivities of C2Hx/CH4 and CO2/CH4. Furthermore, 1 possesses a high density of Brønsted sites and shows efficient catalytic conversion for CO2 cycloaddition with epoxides. Meanwhile, luminescence investigations reveal that 2 can detect nitrofurazone efficiently.


Assuntos
Antibacterianos/análise , Dióxido de Carbono/química , Estruturas Metalorgânicas/química , Adsorção , Catálise , Reação de Cicloadição , Compostos de Epóxi/química , Índio/química , Ligantes , Porosidade , Piridinas/química , Espectrometria de Fluorescência
9.
Chemosphere ; 249: 126099, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32059149

RESUMO

Indium and gallium are used widely in modern industry, mostly for the production of semiconductors. They are considered as Technology-Critical Elements and have therefore received growing attention in the past few years. We investigated the influence of different types of humic substances on the transport of indium and gallium in laboratory-scale, saturated column experiments, to gain understanding of their mobility in natural environments. We evaluated the effect of different humic substances on the transport of indium and gallium in quartz sand: a commercial humic acid (Aldrich Humic Acid, AHA), a fulvic acid (Suwannee River Fulvic Acid, SRFA) and an aquatic natural organic matter (Suwannee River Natural Organic Matter, SRNOM). The impact of the flow rate and the influence of different concentrations of organic matter were also investigated. Indium was shown to be more mobile than gallium in the presence of humic substances. The mobility of indium in sand was highest for SRNOM, followed by SRFA and then AHA, while for gallium the order was SRFA > SRNOM > AHA. These results can be significant in understanding the mobility of indium and gallium in soils with various compositions of organic matter.


Assuntos
Gálio/química , Substâncias Húmicas/análise , Índio/química , Benzopiranos , Modelos Químicos , Porosidade , Rios , Solo
10.
Anal Bioanal Chem ; 412(8): 1893-1899, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32016568

RESUMO

Superoxide dismutase (SOD), also known as liver protein, is a substance widely distributed in various biological cells. It has the function of catalyzing the disproportionation reaction of superoxide free radicals. SOD can form an antioxidant chain together with peroxidase, catalase, and other substances in the body of organisms, and thus, is one of the indispensable important substances in the body of organisms. In this work, we provided a simple and fast visual electrochemiluminescence (ECL) sensor for SOD detection. CuInZnS quantum dots (QDs) worked as the ECL luminophore with hydrogen peroxide as co-reactant. In the sensing process, SOD and CuInZnS QDs on a glassy carbon electrode (GCE) competed with each other for hydrogen peroxide to produce superoxide during electrochemical luminescence, thus quenching the ECL signal of CuInZnS QDs. The proposed sensor can quantify SOD with a limit of detection (LOD) of 0.03 µg/mL. In addition, the change in the CuInZnS QDs ECL signal was easily observed with a smartphone camera. The results indicated that this sensor could effectively work in the detection of SOD in human blood. Graphical abstract.


Assuntos
Cobre/química , Técnicas Eletroquímicas/métodos , Índio/química , Luminescência , Pontos Quânticos/química , Sulfetos/química , Superóxido Dismutase/análise , Compostos de Zinco/química , Técnicas Biossensoriais , Limite de Detecção , Reprodutibilidade dos Testes
11.
Nanotoxicology ; 14(3): 355-371, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31909645

RESUMO

The use of indium oxide (In2O3) and indium-metal hybrids for various applications, including the manufacture of batteries and liquid crystal displays, increases the chances of human exposure to In2O3 via inhalation, especially in occupational settings. However, there is little information available on the toxic effects of In2O3 nanoparticles (NPs) on secondary organs following pulmonary exposure. In this study, we evaluated the effect of In2O3 NPs on atherosclerotic plaque formation and the related mechanisms after pulmonary exposure in low-density lipoprotein receptor knockout (Ldlr-/-) mice. At 10 weeks after a single pharyngeal aspiration, In2O3 NPs caused chronic active inflammation, pulmonary alveolar proteinosis, and accumulation of inflammatory cells in the peribronchial and perivascular areas of the lungs. The expression of pro-inflammatory cytokines in the lung tissue, including TNF-α and MCP-1, was markedly increased by treatment with In2O3 NPs. In the In2O3 NP-treated groups, the levels of total cholesterol and low-density lipoprotein in the plasma were increased, whereas HDL cholesterol showed no significant changes compared to vehicle control. The formation of atherosclerotic lesions was increased by treatment with In2O3 NPs. Real-time PCR analysis of the aorta showed that IL-6 and MCP-1 expression was up-regulated upon treatment with In2O3 NPs. These results suggested that the pulmonary inflammation induced by In2O3 NPs aggravates the progression of atherosclerotic plaque formation, possibly by the alteration of the plasma lipid profile and enhancement of the aortic inflammatory processes.


Assuntos
Aterosclerose/induzido quimicamente , Índio/toxicidade , Nanopartículas/toxicidade , Placa Aterosclerótica/induzido quimicamente , Pneumonia/induzido quimicamente , Receptores de LDL/metabolismo , Animais , Aterosclerose/sangue , Aterosclerose/metabolismo , Citocinas/metabolismo , Índio/química , Exposição por Inalação , Lipoproteínas LDL/sangue , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Knockout , Nanopartículas/química , Placa Aterosclerótica/sangue , Placa Aterosclerótica/metabolismo , Pneumonia/sangue , Pneumonia/metabolismo , Receptores de LDL/genética
12.
Mikrochim Acta ; 187(2): 146, 2020 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-31970525

RESUMO

An optical fiber nanoprobe is presented for fluorometric determination of copper(II). The method based on the use of water-dispersible AgInZnS quantum dots (QDs) deposited at the end of an optical fiber in a poly(vinyl alcohol) matrix. The fluorescnece of the QDs, best measured at excitation/emisssion wavelengths of 365/570 nm, is quenched by Cu(II) due to both static and electron transfer from the QDs to Cu(II). This is experimentally confirmed by photoluminescence and UV-vis absorption spectra, and measurement of luminescence lifetimes. The probe is highly selective and possesses a linear detection range that extends from 2.5 to 800 nM. Graphical abstractSchematic representation of an optical fiber nanoprobe based on hydrophilic AgInZnS quantum dots for fluorometric determination of copper(II). The fluorescence is quenched by Cu(II) due to static quenching and dynamic quenching. It has a detection range of 2.5-800 nM.


Assuntos
Cobre/análise , Corantes Fluorescentes/química , Fibras Ópticas , Pontos Quânticos/química , Índio/química , Lagos/análise , Prata/química , Espectrometria de Fluorescência/instrumentação , Espectrometria de Fluorescência/métodos , Sulfetos/química , Poluentes Químicos da Água/análise , Zinco/química
13.
Mater Sci Eng C Mater Biol Appl ; 108: 110507, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31924009

RESUMO

Developing easy-to-use and miniaturized sensors for in-field monitoring of targets which is related to human health is necessary. Ractopamine (RAC) is a feed additive with serious side effects that is forbidden in many countries. This study reports the fabrication of an impedimetric aptasensor for ultrasensitive and selective detection of the RAC in human biological fluids. Accordingly, an efficient nanocomposites was synthesized by a beneficial combination of graphene quantum dots (GQDs), quantum dots (QDs) and silver nanoparticles (AgNPs) for modifying a glassy carbon electrode (GCE). This nanocomposite is promising to present a synergistic effect in the increase of the active surface area of the modified electrode to more load the biocapture of the target. Next, the RAC-binding aptamer (Apt) was attached to the AgNPs/QDs@GQDs/GCE surface and a sensitive layer for the RAC detection was embedded. A RAC-Apt complex was formed upon adding the RAC and the changes of the electrochemical behavior were studied by some electrochemical techniques such as electrochemical impedance spectroscopy (EIS). Under optimal conditions, the charge transfer resistance (Rct) value was increased linearly with increasing of the RAC concentrations in the range of 1 fM to 901.4 nM. Limit of detection (LOD) was calculated to be 330 aM which is superior by other reported electrochemical methods in the RAC sensing. The applicability of the aptasensor was tested in human urine and blood serum as the real samples and satisfactory results of specificity were achieved. It seems that the proposed strategy not only provides a new ultrasensitive strategy for RAC detection but also expands the application of the sensing interface to develop other aptasensors by changing the Apt sequence.


Assuntos
Análise Química do Sangue/métodos , Impedância Elétrica , Nanopartículas Metálicas/química , Fenetilaminas/análise , Pontos Quânticos , Prata/química , Urinálise/métodos , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais , Cobre/química , Espectroscopia Dielétrica , Técnicas Eletroquímicas , Eletrodos , Grafite/química , Humanos , Índio/química , Limite de Detecção , Microscopia Eletrônica de Varredura , Nanocompostos , Sulfetos/química , Enxofre/química , Compostos de Zinco/química
14.
J Colloid Interface Sci ; 565: 35-42, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31931297

RESUMO

Nanoscale ternary chalcogenides have attracted increasing research interest due to their merits of tunable properties and diverse applications in energy and biomedical fields. In this article, silver indium sulfide quantum dots supported by glutathione and polyethyleneimine as dual-ligands have been synthesized through an environmentally friendly and reproducible aqueous method. An emission quantum yield up to 37.2% has been achieved by glutathione as co-ligand bearing electron-rich groups, much higher than that of polyethyleneimine coated quantum dots (4.97%). Both spectroscopic and structural characterizations demonstrate that the photoluminescence enhancement is attributed to change of surface properties by glutathione as co-ligand. Dynamic light scattering (DLS) results and thermogravimetric analysis (TGA) reveal that glutathione covers the QDs with a higher density on the nanocrystal surface than other co-ligands. Therefore, it can effectively passivate the surface trap centers, thus decreasing the non-radiative emission. Moreover, the resultant silver indium sulfide quantum dots present surprisingly long lifetime of 3.69 µs, excellent fluorescent stability and low cytotoxicity, which enables them to be ideal candidate for real-time bioimaging.


Assuntos
Índio/química , Luminescência , Imagem Óptica , Pontos Quânticos/química , Prata/química , Sulfetos/química , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células HeLa , Humanos , Índio/farmacologia , Ligantes , Tamanho da Partícula , Processos Fotoquímicos , Prata/farmacologia , Relação Estrutura-Atividade , Sulfetos/farmacologia , Propriedades de Superfície
15.
ACS Appl Mater Interfaces ; 12(1): 980-988, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31815416

RESUMO

Brain-like neuromorphic computing system provides an alternative approach for the future computer for its characteristics of high-efficiency, power-efficient, self-learning, and parallel computing. Therefore, the imitation of synapse behavior based on microelectronics is particularly important. Recently, the synaptic transistors have received widespread attention. Among them, solid oxide-based synaptic transistors are more compatible with the large-scale fabrication than the liquid and organic-based transistors. So the development of oxide synaptic transistor is required. Here, a novel aqueous solution-processed Gd2O3 is suggested to be the solid electrolyte for synaptic transistors. The microstructure and the dielectric properties of Gd2O3 film are investigated, which show the potential for the simulation of synaptic transmission. Then, the fully aqueous solution-processed In2O3/Gd2O3 thin-film transistor (TFT) is fabricated. The device exhibits an acceptable electrical performance with a small threshold voltage of 1.24 V, and a small subthreshold swing of 0.12 V/decade. The artificial synapse behavior is stimulated and the short-term plasticity of In2O3/Gd2O3 TFT is studied. The dependence of its excitatory postsynaptic current on presynaptic pulse magnitude, width, and frequency is verified. Besides, the synapse behavior of devices under continuous illumination stresses is investigated. The lights with different photon energy have different effects on the synaptic transmission, which is related to the ionization of oxygen vacancies. Our results demonstrate that fully aqueous solution-processed In2O3 TFT with Gd2O3 solid electrolyte is a candidate for the synaptic transistor.


Assuntos
Eletrólitos/química , Gadolínio/química , Índio/química , Transistores Eletrônicos
16.
Talanta ; 208: 120362, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31816808

RESUMO

Dobutamine (DBT) is a sympathomimetic amine drug that was designed as an inotropic agent for use in congestive heart failure. Hence, there was an impetus to develop a rapid and accurate method for monitoring the concentration of DBT within clinical samples. To address this critical need, a novel In2O3 and functionalized multi-walled carbon nanotubes nanocomposite (In2O3@FMWCNTs) was successfully prepared and applied in an electrochemical sensor to detect DBT. The resulting sensor displayed electrocatalytic toward the oxidation of DBT, which attributed to the synergistic effect of In2O3 and FMWCNTs. Electrochemical impedance spectroscopy (EIS) studies revealed that the smaller charge transfer resistance value (Rct) was observed at In2O3@FMWCNTs modified glassy carbon spherical (GCS) paste electrode (PE) as compared to that of In2O3NPs/GCSPE, FMWCNTs/GCSPE and GCSPE, which authenticates its good conductivity. Furthermore, the calculated value of standard rate constant (ks) for the modified electrode demonstrates the fast electron transfer between DBT and the electrode surface. The fabricated electrochemical sensor indicated high selectivity and sensitivity for DBT determination over the oxidation of uric acid and ascorbic acid. The limit of detection of DBT at In2O3@FMWCNTs/GCSPE was found to be 1.42 × 10-10 M. The proposed sensor is effectively used for the detection of DBT in biological fluids, clinical patient blood and in injection dosage form.


Assuntos
Técnicas Biossensoriais/métodos , Dobutamina/sangue , Técnicas Eletroquímicas/métodos , Eletrodos , Índio/química , Nanocompostos/química , Nanotubos de Carbono/química , Ácido Ascórbico/química , Catálise , Dobutamina/metabolismo , Dobutamina/urina , Formas de Dosagem , Composição de Medicamentos , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Oxirredução , Ácido Úrico/química
17.
Nanotoxicology ; 14(4): 468-478, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31775551

RESUMO

Workplace inhalation exposure to indium compounds has been reported to produce 'indium lung disease' characterized by pulmonary alveolar proteinosis (PAP), granulomas, and pulmonary fibrosis. However, there is little information about the pulmonary toxicity of nano-sized indium oxide (In2O3), which is widely used in various applications such as liquid crystal displays. In this study, we evaluated the time-course and dose-dependent lung injuries by In2O3 nanoparticles (NPs) after a single intratracheal instillation to rats. In2O3 NPs were instilled to female Wistar rats at 7.5, 30, and 90 cm2/rat and lung injuries were evaluated at day 1, 3, 7, 14, 30, 90, and 180 after a single intratracheal instillation. Treatment of In2O3 NPs induced worsening diverse pathological changes including PAP, persistent neutrophilic inflammation, type II cell hyperplasia, foamy macrophages, and granulomas in a time- and dose-dependent manner. PAP was induced from day 3 and worsened throughout the study. The concentrations of interleukin-1ß, tumor necrosis factor-α, and monocyte chemoattractant protein-1 in bronchoalveolar lavage fluid (BALF) showed dose- and time-dependent increases and the levels of these inflammatory mediators are consistent with the data of inflammatory cells in BALF and progressive lung damages by In2O3 NPs. This study suggests that a single inhalation exposure to In2O3 NPs can produce worsening lung damages such as PAP, chronic active inflammation, infiltration of foamy macrophages, and granulomas. The early onset and persistent PAP even at the very low dose (7.5 cm2/rat) implies that the re-evaluation of occupational recommended exposure limit for In2O3 NPs is urgently needed to protect workers.


Assuntos
Índio/toxicidade , Exposição por Inalação/efeitos adversos , Nanopartículas/toxicidade , Proteinose Alveolar Pulmonar/induzido quimicamente , Animais , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/imunologia , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Feminino , Índio/química , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Nanopartículas/química , Proteinose Alveolar Pulmonar/patologia , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/patologia , Ratos , Ratos Wistar , Fatores de Tempo
18.
ACS Appl Mater Interfaces ; 12(1): 1061-1068, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31820620

RESUMO

Emulating the essential synaptic behaviors using single synaptic transistor has attracted extensive attention for building the brain-inspired neuromorphic systems. However, few reports on synaptic transistors fabricated by solution processes have been reported. In this article, the indium oxide synaptic transistors based on polyimide substrates were fabricated by a nontoxic water-inducement method at a low temperature, and lithium perchlorate (LiClO4) was dissolved in polyethylene oxide as the gate electrolyte. For water-inducement process, comparable electrical properties of the synaptic transistors can be achieved by prolonging the annealing time rather than high-temperature annealing with a relatively short time. The effect of the annealing time on the electrical performance of the electrolyte-gated transistors annealed at various temperatures was investigated. It is found that the electrolyte-gated-synaptic transistor on polyimide substrate annealed at 200 °C exhibits high electrical performance and good mechanical stability. Due to the ion migration relaxation dynamics in the polymer electrolyte, various important synaptic behaviors such as the excitatory postsynaptic current, paired-pulse facilitation, high-pass filtering characteristics, and long-term memory performance were successfully mimicked. The electrolyte-gated synaptic transistors based on solution-processed In2O3 exhibit great potential in neuromorphological applications.


Assuntos
Encéfalo/metabolismo , Eletrólitos/química , Índio/química , Transistores Eletrônicos , Compostos de Lítio/química , Percloratos/química , Temperatura
19.
Artigo em Inglês | MEDLINE | ID: mdl-31607225

RESUMO

III-V semiconductor materials such as gallium arsenide (GaAs) and indium arsenide (InAs) are increasingly used in the fabrication of electronic devices. There is a growing concern about the potential release of these materials into the environment leading to effects on public and environmental health. The waste effluents from the chemical mechanical planarization process could impact microorganisms in biological wastewater treatment systems. Currently, there is only limited information about the inhibition of gallium- and indium-based nanoparticles (NPs) on microorganisms. This study evaluated the acute toxicity of GaAs, InAs, gallium oxide (Ga2O3), and indium oxide (In2O3) particulates using two microbial inhibition assays targeting methanogenic archaea and the marine bacterium, Aliivibrio fischeri. GaAs and InAs NPs were acutely toxic towards these microorganisms; Ga2O3 and In2O3 NPs were not. The toxic effect was mainly due to the release of soluble arsenic species and it increased with decreasing particle size and with increasing time due to the progressive corrosion of the NPs in the aqueous bioassay medium. Collectively, the results indicate that the toxicity exerted by the arsenide NPs under environmental conditions will vary depending on intrinsic properties of the material such as particle size as well as on the dissolution time and aqueous chemistry.


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Gálio/toxicidade , Índio/toxicidade , Nanopartículas/toxicidade , Poluentes Químicos da Água/toxicidade , Aliivibrio fischeri/metabolismo , Arsenicais/química , Gálio/química , Índio/química , Metano/biossíntese , Nanopartículas/química , Tamanho da Partícula , Semicondutores , Esgotos/microbiologia , Propriedades de Superfície , Poluentes Químicos da Água/química , Purificação da Água/métodos
20.
Molecules ; 24(23)2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31795117

RESUMO

This review presents the most recent developments on the synthesis of dipyrromethanes, covering classical synthetic strategies, using acid catalyzed condensation of pyrroles and aldehydes or ketones, and recent breakthroughs which allow the synthesis of these type of heterocycles with new substitution patterns.


Assuntos
Pirróis/síntese química , Aldeídos/química , Catálise , Técnicas de Química Sintética , Ácido Clorídrico , Índio/química , Estrutura Molecular , Pirróis/química
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