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1.
Nucleic Acids Res ; 48(19): 10691-10701, 2020 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-33045746

RESUMO

Designing biochemical systems that can be effectively used in diverse fields, including diagnostics, molecular computing and nanomachines, has long been recognized as an important goal of molecular programming and DNA nanotechnology. A key issue in the development of such practical devices on the nanoscale lies in the development of biochemical components with information-processing capacity. In this article, we propose a molecular device that utilizes DNA strand displacement networks and allows interactive inhibition between two input signals; thus, it is termed a cross-inhibitor. More specifically, the device supplies each input signal with a processor such that the processing of one input signal will interdict the signal of the other. Biochemical experiments are conducted to analyze the interdiction performance with regard to effectiveness, stability and controllability. To illustrate its feasibility, a biochemical framework grounded in this mechanism is presented to determine the winner of a tic-tac-toe game. Our results highlight the potential for DNA strand displacement cascades to act as signal controllers and event triggers to endow molecular systems with the capability of controlling and detecting events and signals.


Assuntos
Pareamento de Bases , Técnicas Biossensoriais/métodos , DNA/química , Nanotecnologia/métodos , Técnicas Biossensoriais/instrumentação , Metodologias Computacionais , Nanotecnologia/instrumentação
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.
Food Chem ; 332: 127431, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32645668

RESUMO

Illegal usage of ß-agonists as the animal growth promoters can lead to multiple harmful impacts to public health, thus detection of ß-agonists at trace level in complex sample matrixes is of great importance. In recent years, emergence of advanced nanomaterials greatly facilitates the advancement of sensors in terms of sensitivity, specificity and robustness. Plenty of nanoparticles-based sensors have been developed for ß-agonists determination. In this review, we comprehensively summarized the construction of emerging nanoparticles-based sensors (including colorimetric sensors, fluorescent sensors, chemiluminescent sensors, electrochemical sensors, electrochemiluminescent sensors, surface enhanced Raman scattering sensors, surface plasmon resonance sensors, quartz crystal microbalance sensors, etc.), and nanomaterial-based enzyme-linked immunosorbent assay (nano-ELISA). Impressively, the applications of nanoparticles-based sensors and nano-ELISAs in the detection of ß-agonists have also been summarized and discussed. In the end, future opportunities and challenges in the design construction of nanoparticles (NPs)-based sensors and their applications in ß-agonist assay are tentatively proposed.


Assuntos
Agonistas Adrenérgicos/análise , Nanoestruturas/química , Animais , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Colorimetria/instrumentação , Colorimetria/métodos , Humanos , Nanotecnologia/instrumentação , Nanotecnologia/métodos , Análise Espectral Raman/instrumentação , Análise Espectral Raman/métodos , Ressonância de Plasmônio de Superfície/instrumentação , Ressonância de Plasmônio de Superfície/métodos
4.
Nat Commun ; 11(1): 3781, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32728047

RESUMO

Nanomechanical mass spectrometry has proven to be well suited for the analysis of high mass species such as viruses. Still, the use of one-dimensional devices such as vibrating beams forces a trade-off between analysis time and mass resolution. Complex readout schemes are also required to simultaneously monitor multiple resonance modes, which degrades resolution. These issues restrict nanomechanical MS to specific species. We demonstrate here single-particle mass spectrometry with nano-optomechanical resonators fabricated with a Very Large Scale Integration process. The unique motion sensitivity of optomechanics allows designs that are impervious to particle position, stiffness or shape, opening the way to the analysis of large aspect ratio biological objects of great significance such as viruses with a tail or fibrils. Compared to top-down beam resonators with electrical read-out and state-of-the-art mass resolution, we show a three-fold improvement in capture area with no resolution degradation, despite the use of a single resonance mode.


Assuntos
Espectrometria de Massas/métodos , Nanotecnologia/métodos , Dispositivos Ópticos , Imagem Individual de Molécula/métodos , Amiloide/química , Desenho de Equipamento , Espectrometria de Massas/instrumentação , Nanopartículas/química , Nanotecnologia/instrumentação , Imagem Individual de Molécula/instrumentação , Vírus/química
5.
ACS Nano ; 14(4): 5135-5142, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: covidwho-59591

RESUMO

Coronavirus disease 2019 (COVID-19) is a newly emerging human infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, previously called 2019-nCoV). Based on the rapid increase in the rate of human infection, the World Health Organization (WHO) has classified the COVID-19 outbreak as a pandemic. Because no specific drugs or vaccines for COVID-19 are yet available, early diagnosis and management are crucial for containing the outbreak. Here, we report a field-effect transistor (FET)-based biosensing device for detecting SARS-CoV-2 in clinical samples. The sensor was produced by coating graphene sheets of the FET with a specific antibody against SARS-CoV-2 spike protein. The performance of the sensor was determined using antigen protein, cultured virus, and nasopharyngeal swab specimens from COVID-19 patients. Our FET device could detect the SARS-CoV-2 spike protein at concentrations of 1 fg/mL in phosphate-buffered saline and 100 fg/mL clinical transport medium. In addition, the FET sensor successfully detected SARS-CoV-2 in culture medium (limit of detection [LOD]: 1.6 × 101 pfu/mL) and clinical samples (LOD: 2.42 × 102 copies/mL). Thus, we have successfully fabricated a promising FET biosensor for SARS-CoV-2; our device is a highly sensitive immunological diagnostic method for COVID-19 that requires no sample pretreatment or labeling.


Assuntos
Betacoronavirus/isolamento & purificação , Técnicas Biossensoriais , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Transistores Eletrônicos , Técnicas de Laboratório Clínico , Grafite , Humanos , Nanotecnologia/instrumentação , Cavidade Nasal , Pandemias , Manejo de Espécimes
6.
Nat Commun ; 11(1): 1861, 2020 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-32313096

RESUMO

Memristive devices are promising candidates to emulate biological computing. However, the typical switching voltages (0.2-2 V) in previously described devices are much higher than the amplitude in biological counterparts. Here we demonstrate a type of diffusive memristor, fabricated from the protein nanowires harvested from the bacterium Geobacter sulfurreducens, that functions at the biological voltages of 40-100 mV. Memristive function at biological voltages is possible because the protein nanowires catalyze metallization. Artificial neurons built from these memristors not only function at biological action potentials (e.g., 100 mV, 1 ms) but also exhibit temporal integration close to that in biological neurons. The potential of using the memristor to directly process biosensing signals is also demonstrated.


Assuntos
Potenciais de Ação , Eletrônica/instrumentação , Geobacter/metabolismo , Nanofios/química , Neurônios , Técnicas Biossensoriais , Eletricidade , Desenho de Equipamento , Humanos , Simulação de Dinâmica Molecular , Nanotecnologia/instrumentação , Nanofios/ultraestrutura , Redes Neurais de Computação , Sinapses/metabolismo , Dispositivos Eletrônicos Vestíveis
7.
ACS Nano ; 14(4): 5135-5142, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32293168

RESUMO

Coronavirus disease 2019 (COVID-19) is a newly emerging human infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, previously called 2019-nCoV). Based on the rapid increase in the rate of human infection, the World Health Organization (WHO) has classified the COVID-19 outbreak as a pandemic. Because no specific drugs or vaccines for COVID-19 are yet available, early diagnosis and management are crucial for containing the outbreak. Here, we report a field-effect transistor (FET)-based biosensing device for detecting SARS-CoV-2 in clinical samples. The sensor was produced by coating graphene sheets of the FET with a specific antibody against SARS-CoV-2 spike protein. The performance of the sensor was determined using antigen protein, cultured virus, and nasopharyngeal swab specimens from COVID-19 patients. Our FET device could detect the SARS-CoV-2 spike protein at concentrations of 1 fg/mL in phosphate-buffered saline and 100 fg/mL clinical transport medium. In addition, the FET sensor successfully detected SARS-CoV-2 in culture medium (limit of detection [LOD]: 1.6 × 101 pfu/mL) and clinical samples (LOD: 2.42 × 102 copies/mL). Thus, we have successfully fabricated a promising FET biosensor for SARS-CoV-2; our device is a highly sensitive immunological diagnostic method for COVID-19 that requires no sample pretreatment or labeling.


Assuntos
Betacoronavirus/isolamento & purificação , Técnicas Biossensoriais , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Transistores Eletrônicos , Técnicas de Laboratório Clínico , Grafite , Humanos , Nanotecnologia/instrumentação , Cavidade Nasal , Pandemias , Manejo de Espécimes
8.
Chemistry ; 26(25): 5676-5684, 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32022377

RESUMO

DNA nanostructures have been designed and used in many different applications. However, the use of nucleic acid scaffolds to promote the self-assembly of artificial protein mimics is only starting to emerge. Herein five coiled-coil peptide structures were templated by the hybridization of a d-DNA triplex or its mirror-image counterpart, an l-DNA triplex. The self-assembly of the desired trimeric structures in solution was confirmed by gel electrophoresis and small-angle X-ray scattering, and the stabilizing synergy between the two domains was found to be chirality-independent but orientation-dependent. This is the first example of using a nucleic acid scaffold of l-DNA to template the formation of artificial protein mimics. The results may advance the emerging POC-based nanotechnology field by adding two extra dimensions, that is, chirality and polarity, to provide innovative molecular tools for rational design and bottom-up construction of artificial protein mimics, programmable materials and responsive nanodevices.


Assuntos
DNA/química , Nanotecnologia/métodos , Modelos Moleculares , Nanoestruturas/química , Nanotecnologia/instrumentação , Hibridização de Ácido Nucleico , Peptídeos/química , Domínios Proteicos
9.
Int J Mol Sci ; 21(3)2020 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-32024227

RESUMO

We report a highly compliant process for patterning nanoparticle arrays on micro- and nanomechanical devices. The distinctive step involves the single layer self-assembled nanoparticles on top of released nanomechanical devices. We demonstrate the process by fabricating sizable arrays of nanomechanical devices on silicon-on-insulator substrates, acting as nanomechanical torque magnetometers. Later, the nanoparticles were self-assembled in geometrical shapes on top of the devices by a unique combination of top-down and bottom-up methods. The self-assembled array of nanoparticles successfully showed a magnetic torque signal by magnetic actuation of the magnetometer. This patterning process can be generalized for any shape and for a wide range of nanoparticles on the nanomechanical resonators.


Assuntos
Nanopartículas de Magnetita/química , Magnetometria/instrumentação , Magnetometria/métodos , Nanotecnologia/métodos , Compostos de Silício/química , Torque , Nanotecnologia/instrumentação , Semicondutores
10.
Sci Rep ; 10(1): 1255, 2020 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-31988397

RESUMO

Biosynaptic devices based on chicken egg albumen (CEA):graphene quantum dot (GQD) hybrid nanocomposites were fabricated to achieve stable synaptic behaviors. Current-voltage (I-V) curves for the biosynaptic devices under consecutive negative and positive voltage sweeps showed clockwise pinched hysteresis, which is a critical feature of a biological synapse. The effect of the GQD concentration in the CEA layer on the device performance was studied. The retention time of the biosynaptic devices was relatively constant, maintaining a value above 104 s under ambient conditions. The carrier transport mechanisms of the biosynaptic devices were described and analyzed on the basis of the slopes of the I-V curves and their fittings.


Assuntos
Grafite/química , Nanocompostos/química , Pontos Quânticos/química , Animais , Galinhas , Impedância Elétrica , Transporte de Elétrons , Eletrofisiologia/instrumentação , Eletrofisiologia/métodos , Nanotecnologia/instrumentação , Ovalbumina/química , Eletricidade Estática , Sinapses/metabolismo
11.
Nat Commun ; 11(1): 175, 2020 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-31924752

RESUMO

Challenges in drug development of neurological diseases remain mainly ascribed to the blood-brain barrier (BBB). Despite the valuable contribution of animal models to drug discovery, it remains difficult to conduct mechanistic studies on the barrier function and interactions with drugs at molecular and cellular levels. Here we present a microphysiological platform that recapitulates the key structure and function of the human BBB and enables 3D mapping of nanoparticle distributions in the vascular and perivascular regions. We demonstrate on-chip mimicry of the BBB structure and function by cellular interactions, key gene expressions, low permeability, and 3D astrocytic network with reduced reactive gliosis and polarized aquaporin-4 (AQP4) distribution. Moreover, our model precisely captures 3D nanoparticle distributions at cellular levels and demonstrates the distinct cellular uptakes and BBB penetrations through receptor-mediated transcytosis. Our BBB platform may present a complementary in vitro model to animal models for prescreening drug candidates for the treatment of neurological diseases.


Assuntos
Transporte Biológico/fisiologia , Engenharia Biomédica/métodos , Barreira Hematoencefálica/metabolismo , Dispositivos Lab-On-A-Chip , Nanopartículas/química , Nanotecnologia/métodos , Animais , Aquaporina 4/metabolismo , Astrócitos/metabolismo , Engenharia Biomédica/instrumentação , Técnicas de Cultura de Células/métodos , Sistemas de Liberação de Medicamentos , Descoberta de Drogas , Citometria de Fluxo , Expressão Gênica , Gliose , Humanos , Modelos Animais , Nanotecnologia/instrumentação , Permeabilidade , Transcitose
12.
Sci China Life Sci ; 63(8): 1159-1167, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31974862

RESUMO

Various nanobiosensors composed of biomaterials and nanomaterials have been developed, due to their demonstrated advantage of showing high performance. Among various biomaterials for biological recognition elements of the nanobiosensor, sensory receptors, such as olfactory and taste receptors, are promising biomaterials for developing nanobiosensors, because of their high selectivity to target molecules. Field-effect transistors (FET) with nanomaterials such as carbon nanotube (CNT), graphene, and conducting polymer nanotube (CPNT), can be combined with the biomaterials to enhance the sensitivity of nanobiosensors. Recently, many efforts have been made to develop nanobiosensors using biomaterials, such as olfactory receptors and taste receptors for detecting various smells and tastes. This review focuses on the biomaterials and nanomaterials used in nanobiosensor systems and studies of various types of nanobiosensor platforms that utilize olfactory receptors and taste receptors which could be applied to a wide range of industrial fields, including the food and beverage industry, environmental monitoring, the biomedical field, and anti-terrorism.


Assuntos
Materiais Biocompatíveis/química , Técnicas Biossensoriais/instrumentação , Nanoestruturas/química , Nanotecnologia/instrumentação , Transistores Eletrônicos , Condutividade Elétrica , Desenho de Equipamento , Humanos , Proteínas Imobilizadas/metabolismo , Polímeros/química , Receptores Acoplados a Proteínas-G/metabolismo , Receptores Odorantes/metabolismo , Olfato , Propriedades de Superfície , Paladar
13.
Nanoscale ; 12(4): 2479-2491, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31916549

RESUMO

Chiral nanohole array (CNA) films are fabricated by a simple and efficient shadow sphere lithography (SSL) method and achieve label-free enantiodiscrimination of biomolecules and drug molecules at the picogram level. The intrinsic mirror symmetry of the structure is broken by three subsequent depositions onto non-close packed nanosphere monolayers with different polar and azimuthal angles. Giant chiro-optical responses with a transmission as high as 45%, a chirality of 21°µm-1, and a g-factor of 0.17, respectively, are generated, which are among the largest values that have been reported in the literature. Such properties are due to the local rotating current density generated by a surface plasmon polariton as well as a strong local rotating field produced by localized surface plasmon resonance, which leads to the excitation of substantial local superchiral fields. The 70 nm-thick CNAs can achieve label-free enantiodiscrimination of biomolecules and drug molecules at the picogram level as demonstrated experimentally. All these advantages make the CNAs ready for low-cost, high-performance, and ultracompact polarization converters and label-free chiral sensors.


Assuntos
Nanoestruturas/química , Nanotecnologia/instrumentação , Ressonância de Plasmônio de Superfície/instrumentação , Nanopartículas Metálicas/química , Impressão Molecular , Nanosferas/química , Rotação Ocular , Prata/química , Propriedades de Superfície
14.
Nat Protoc ; 15(1): 122-143, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31836867

RESUMO

Solid-state nanopores are now well established as single-biomolecule sensors that hold great promise as sensing elements in diagnostic and sequencing applications. However, until recently this promise has been limited by the expensive, labor-intensive, and low-yield methods used to fabricate low-noise and precisely sized pores. To address this problem, we pioneered a low-cost and scalable solid-state nanopore fabrication method, termed controlled breakdown (CBD), which is rapidly becoming the method of choice for fabricating solid-state nanopores. Since its initial development, nanopore research groups around the world have applied and adapted the CBD method in a variety of ways, with varying levels of success. In this work, we present our accumulated knowledge of nanopore fabrication by CBD, including a detailed description of the instrumentation, software, and procedures required to reliably fabricate low-noise and precisely sized solid-state nanopores with a yield of >85% in less than 1 h. The assembly instructions for the various custom instruments can be found in the Supplementary Manual, and take approximately a day to complete, depending on the unit that the user is building and their level of skill with mechanical and electrical assembly. Unlike traditional beam-based nanopore fabrication technologies, the methods presented here are accessible to non-experts, lowering the cost of, and technical barriers to, fabricating nanoscale pores in thin solid-state membranes.


Assuntos
Nanoporos , Nanotecnologia/instrumentação , Automação , Membranas Artificiais
15.
Nat Biomed Eng ; 4(2): 232-241, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31548592

RESUMO

Current electrophysiological or optical techniques cannot reliably perform simultaneous intracellular recordings from more than a few tens of neurons. Here we report a nanoelectrode array that can simultaneously obtain intracellular recordings from thousands of connected mammalian neurons in vitro. The array consists of 4,096 platinum-black electrodes with nanoscale roughness fabricated on top of a silicon chip that monolithically integrates 4,096 microscale amplifiers, configurable into pseudocurrent-clamp mode (for concurrent current injection and voltage recording) or into pseudovoltage-clamp mode (for concurrent voltage application and current recording). We used the array in pseudovoltage-clamp mode to measure the effects of drugs on ion-channel currents. In pseudocurrent-clamp mode, the array intracellularly recorded action potentials and postsynaptic potentials from thousands of neurons. In addition, we mapped over 300 excitatory and inhibitory synaptic connections from more than 1,700 neurons that were intracellularly recorded for 19 min. This high-throughput intracellular-recording technology could benefit functional connectome mapping, electrophysiological screening and other functional interrogations of neuronal networks.


Assuntos
Eletrofisiologia/instrumentação , Eletrofisiologia/métodos , Potenciais da Membrana , Nanotecnologia/instrumentação , Neurônios/fisiologia , Animais , Células Cultivadas , Estimulação Elétrica , Microeletrodos , Ratos , Sinapses/fisiologia
16.
Talanta ; 207: 120340, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31594582

RESUMO

The emitter clogging is the most common hardware failure of nano-electrospray ionization, to improve the durability and electrospray stability of fused silica emitters, we demonstrate a means of fabricating nano-electrospray emitters with controllable aperture size and gradually-narrowed channel on the tip. We simulated the fluid morphologies in the emitter channels by computational fluid dynamics and found more stable flow on aperture-controllable nano-electrospray emitter. Besides, we found the unstable flow sections of commercial emitters match the actual clogging sections very well, indicating the main cause of emitter clogging is unstable flow. We further tested the emitters by nano-LC-MS based proteome analysis. Compared with the commercial emitter, aperture-controllable nano-electrospray emitters promoted the total ion chromatogram intensity by 25%, the number of identified proteins by 6.58%, and the number of identified peptides by 7.87%. In total, 989 proteins were identified from 1 µg of extracted mouse cardiac proteins. After the optimization by using mouse samples, we analyzed clinical auricular dextral tissues from patients undergoing cardiac surgery and found 16 proteins related to atrial fibrillation. Overall, aperture-controllable nano-electrospray emitter exhibits better sensitivity and reproducibility in the application of nano-LC-MS cardiac proteome analysis.


Assuntos
Miocárdio/metabolismo , Nanotecnologia/instrumentação , Proteômica/instrumentação , Espectrometria de Massas por Ionização por Electrospray/instrumentação , Fibrilação Atrial/metabolismo , Simulação por Computador , Desenho de Equipamento , Humanos , Hidrodinâmica
17.
Mikrochim Acta ; 187(1): 8, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31797057

RESUMO

A surface plasmon resonance study was carried out for the identification and determination of the organophosphate pesticide fenitrothion via an optical fiber sensor. A thin layer of silver was deposited on the unclad core of silica optical fiber for plasmon generation. This was followed by the deposition of a sensing surface comprising a layer of tantalum(V) oxide nanoparticles sequestered in a nano-scaled matrix of reduced graphene oxide. The sensing mechanism is due to the interaction of fenitrothion with the silver film which leads to a change in refractive index.. Characterized by a wavelength interrogation scheme, the fiber-optic sensor exhibited a red shift equalling 56 nm corresponding to fenitrothion concentration in the range 0.25-4 µM including the blank solution. The spectral sensitivity is 24 nm µM-1, the limit of detection is 38 nM, and the response time is as short as 23 s. The sensor is selective, repeatable and works at ambient temperature. Graphical abstractSchematic representation of the sensing mechanism of an SPR based fiber-optic fenitrothion sensor utilizing modification in refractive index of sensing surface comprising of tantalum(V) oxide (Ta2O5) nanoparticles embedded in reduced graphene oxide (rGO) caused by interaction with fenitrothion entities.


Assuntos
Fenitrotion/análise , Grafite/química , Nanotecnologia/instrumentação , Fibras Ópticas , Óxidos/química , Praguicidas/análise , Ressonância de Plasmônio de Superfície/instrumentação , Tantálio/química , Calibragem , Fenitrotion/química , Limite de Detecção , Oxirredução , Praguicidas/química , Fatores de Tempo
18.
Nat Commun ; 10(1): 5597, 2019 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-31811136

RESUMO

The inherent specificity of DNA sequence hybridization has been extensively exploited to develop bioengineering applications. Nevertheless, the structural potential of DNA has been far less explored for creating non-canonical DNA-based reactions. Here we develop a DNA origami-enabled highly localized metallization reaction for intrinsic metallization patterning with 10-nm resolution. Both theoretical and experimental studies reveal that low-valence metal ions (Cu2+ and Ag+) strongly coordinate with DNA bases in protruding clustered DNA (pcDNA) prescribed on two-dimensional DNA origami, which results in effective attraction within flexible pcDNA strands for site-specific pcDNA condensation. We find that the metallization reactions occur selectively on prescribed sites while not on origami substrates. This strategy is generically applicable for free-style metal painting of alphabet letters, digits and geometric shapes on all-DNA substrates with near-unity efficiency. We have further fabricated single- and double-layer nanoscale printed circuit board (nano-PCB) mimics, shedding light on bio-inspired fabrication for nanoelectronic and nanophotonic applications.


Assuntos
DNA/química , Nanopartículas Metálicas/química , Metais/química , Nanoestruturas/química , Cobre/química , DNA/ultraestrutura , Ouro/química , Microscopia de Força Atômica , Microscopia Eletrônica , Modelos Teóricos , Nanoestruturas/ultraestrutura , Nanotecnologia/instrumentação , Conformação de Ácido Nucleico , Espectroscopia Fotoeletrônica
19.
Sensors (Basel) ; 19(24)2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31817067

RESUMO

With the rapid development of low-power consumption wireless sensors and wearable electronics, harvesting energy from human motion to enable self-powered sensing is becoming desirable. Herein, a pair of smart insoles integrated with piezoelectric poly(vinylidene fluoride) (PVDF) nanogenerators (NGs) are fabricated to simultaneously harvest energy from human motion and monitor human gait signals. Multi-target magnetron sputtering technology is applied to form the aluminum electrode layers on the surface of the PVDF film and the self-powered insoles are fabricated through advanced 3D seamless flat-bed knitting technology. Output responses of the NGs are measured at different motion speeds and a maximum value of 41 V is obtained, corresponding to an output power of 168.1 µW. By connecting one NG with an external circuit, the influence of external resistance, capacitor, and motion speed on the charging characteristics of the system is systematically investigated. To demonstrate the potential of the smart insoles for monitoring human gait signals, two subjects were asked to walk on a treadmill at different speeds or with a limp. The results show that one can clearly distinguish walking with a limp from regular slow, normal, and fast walking states by using multiscale entropy analysis of the stride intervals.


Assuntos
Marcha , Nanotecnologia/métodos , Fontes de Energia Elétrica , Humanos , Nanotecnologia/instrumentação , Polivinil/química , Sapatos , Dispositivos Eletrônicos Vestíveis , Tecnologia sem Fio
20.
Nat Commun ; 10(1): 5147, 2019 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-31772189

RESUMO

In the new era of internet of things, big data collection and analysis based on widely distributed intelligent sensing technology is particularly important. Here, we report a flexible and durable wood-based triboelectric nanogenerator for self-powered sensing in athletic big data analytics. Based on a simple and effective strategy, natural wood can be converted into a high-performance triboelectric material with excellent mechanical properties, such as 7.5-fold enhancement in strength, superior flexibility, wear resistance and processability. The electrical output performance is also enhanced by more than 70% compared with natural wood. A self-powered falling point distribution statistical system and an edge ball judgement system are further developed to provide training guidance and real-time competition assistance for both athletes and referees. This work can not only expand the application area of the self-powered system to smart sport monitoring and assisting, but also promote the development of big data analytics in intelligent sports industry.


Assuntos
Atletas , Interpretação Estatística de Dados , Fontes de Energia Elétrica , Madeira/química , Big Data , Eletrodos , Desenho de Equipamento , Humanos , Microscopia Eletrônica de Varredura , Nanoestruturas , Nanotecnologia/instrumentação , Espectroscopia de Infravermelho com Transformada de Fourier , Esportes/estatística & dados numéricos
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