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1.
Biosens Bioelectron ; 257: 116302, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38648705

RESUMO

This review article focuses on the recent printing technological progress in healthcare, underscoring the significant potential of implantable devices across diverse applications. Printing technologies have widespread use in developing health monitoring devices, diagnostic systems, and surgical devices. Recent years have witnessed remarkable progress in fabricating low-profile implantable devices, driven by advancements in printing technologies and nanomaterials. The importance of implantable biosensors and bioelectronics is highlighted, specifically exploring printing tools using bio-printable inks for practical applications, including a detailed examination of fabrication processes and essential parameters. This review also justifies the need for mechanical and electrical compatibility between bioelectronics and biological tissues. In addition to technological aspects, this article delves into the importance of appropriate packaging methods to enhance implantable devices' performance, compatibility, and longevity, which are made possible by integrating cutting-edge printing technology. Collectively, we aim to shed light on the holistic landscape of implantable biosensors and bioelectronics, showcasing their evolving role in advancing healthcare through innovative printing technologies.


Assuntos
Técnicas Biossensoriais , Próteses e Implantes , Técnicas Biossensoriais/instrumentação , Humanos , Eletrônica/instrumentação , Impressão Tridimensional , Desenho de Equipamento , Nanoestruturas/química , Atenção à Saúde/tendências
2.
Food Chem ; 448: 139127, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38608399

RESUMO

To address the food safety issues caused by toxins, we established a fluorescent copper nanocluster biosensor based on magnetic aptamer for the visual and quantitative detection of ZEN. Specifically, we utilized the docking-aided rational tailoring (DART) strategy to analyze intermolecular force and interaction sites between zearalenone (ZEN) and the aptamer, and optimize the long-chain aptamer step by step to enhance the binding affinity by 3.4 times. The magnetic bead-modified aptamer underwent conformational changes when competing with complementary sequences to bind with ZEN. Then, the released complementary sequences will be amplified in template-free mode with the presence of the terminal deoxynucleotidyl transferase (TdT), and generating T-rich sequences as the core sequences for the luminescence of copper nanoclusters. The luminescence could be visualized and quantitatively detected through ultraviolet irradiation. The proposed label-free aptasensor exhibited high sensitivity and specificity, with a low limit of detection (LOD) of 0.1 ng/mL.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Cobre , Zearalenona , Zearalenona/análise , Zearalenona/química , Cobre/química , Técnicas Biossensoriais/instrumentação , Aptâmeros de Nucleotídeos/química , Contaminação de Alimentos/análise , Limite de Detecção , Simulação de Acoplamento Molecular , Nanopartículas Metálicas/química , Fluorescência
3.
PLoS One ; 17(2): e0263401, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35130303

RESUMO

In the research on energy-efficient networking methods for precision agriculture, a hot topic is the energy issue of sensing nodes for individual wireless sensor networks. The sensing nodes of the wireless sensor network should be enabled to provide better services with limited energy to support wide-range and multi-scenario acquisition and transmission of three-dimensional crop information. Further, the life cycle of the sensing nodes should be maximized under limited energy. The transmission direction and node power consumption are considered, and the forward and high-energy nodes are selected as the preferred cluster heads or data-forwarding nodes. Taking the cropland cultivation of ginseng as the background, we put forward a particle swarm optimization-based networking algorithm for wireless sensor networks with excellent performance. This algorithm can be used for precision agriculture and achieve optimal equipment configuration in a network under limited energy, while ensuring reliable communication in the network. The node scale is configured as 50 to 300 nodes in the range of 500 × 500 m2, and simulated testing is conducted with the LEACH, BCDCP, and ECHERP routing protocols. Compared with the existing LEACH, BCDCP, and ECHERP routing protocols, the proposed networking method can achieve the network lifetime prolongation and mitigate the decreased degree and decreasing trend of the distance between the sensing nodes and center nodes of the sensor network, which results in a longer network life cycle and stronger environment suitability. It is an effective method that improves the sensing node lifetime for a wireless sensor network applied to cropland cultivation of ginseng.


Assuntos
Agricultura , Algoritmos , Redes de Comunicação de Computadores , Panax/crescimento & desenvolvimento , Agricultura/instrumentação , Agricultura/métodos , Agricultura/organização & administração , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , China , Redes de Comunicação de Computadores/instrumentação , Redes de Comunicação de Computadores/organização & administração , Simulação por Computador , Produtos Agrícolas/crescimento & desenvolvimento , Coleta de Dados/instrumentação , Coleta de Dados/métodos , Humanos , Tecnologia sem Fio/instrumentação , Tecnologia sem Fio/organização & administração
4.
ACS Appl Mater Interfaces ; 14(1): 150-158, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34937345

RESUMO

We report an experimental and computational approach for the fabrication and characterization of a highly sensitive and responsive label-free biosensor that does not require the presence of redox couples in electrolytes for sensitive electrochemical detection. The sensor is based on an aptamer-functionalized transparent electrode composed of nanoporous anodized alumina (NAA) grown on indium tin oxide (ITO)-covered glass. Electrochemical impedance changes in a thrombin binding aptamer (TBA)-functionalized NAA/ITO/glass electrode due to specific binding of α-thrombin are monitored for protein detection. The aptamer-functionalized electrode enables sensitive and specific thrombin protein detection with a detection limit of ∼10 pM and a high signal-to-noise ratio. The transient impedance of the alumina film-covered surface is computed using a computational electrochemical impedance spectroscopy (EIS) approach and compared to experimental observations to identify the dominant mechanisms underlying the sensor response. The computational and experimental results indicate that the sensing response is due to the modified ionic transport under the combined influence of steric hindrance and surface charge modification due to ligand/receptor binding between α-thrombin and the aptamer-covered alumina film. These results suggest that alumina film-covered electrodes utilize both steric and charge modulation for sensing, leading to tremendous improvement in the sensitivity and signal-to-noise ratio. The film configuration is amenable for miniaturization and can be readily incorporated into existing portable sensing systems.


Assuntos
Óxido de Alumínio/química , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Nanoporos , Trombina/análise , Compostos de Estanho/química , Técnicas Biossensoriais/instrumentação , Espectroscopia Dielétrica/instrumentação , Espectroscopia Dielétrica/métodos , Impedância Elétrica , Eletrodos , Limite de Detecção
5.
Adv Sci (Weinh) ; 9(4): e2102924, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34898053

RESUMO

The combination of 2D materials and optical biosensors has become a hot research topic in recent years. Graphene, transition metal dichalcogenides, black phosphorus, MXenes, and other 2D materials (metal oxides and degenerate semiconductors) have unique optical properties and play a unique role in the detection of different biomolecules. Through the modification of 2D materials, optical biosensor has the advantages that traditional sensors (such as electrical sensing) do not have, and the sensitivity and detection limit are greatly improved. Here, optical biosensors based on different 2D materials are reviewed. First, various detection methods of biomolecules, including surface plasmon resonance (SPR), fluorescence resonance energy transfer (FRET), and evanescent wave and properties, preparation and integration strategies of 2D material, are introduced in detail. Second, various biosensors based on 2D materials are summarized. Furthermore, the applications of these optical biosensors in biological imaging, food safety, pollution prevention/control, and biological medicine are discussed. Finally, the future development of optical biosensors is prospected. It is believed that with their in-depth research in the laboratory, optical biosensors will gradually become commercialized and improve people's quality of life in many aspects.


Assuntos
Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Transferência Ressonante de Energia de Fluorescência/instrumentação , Transferência Ressonante de Energia de Fluorescência/métodos , Ressonância de Plasmônio de Superfície/instrumentação , Ressonância de Plasmônio de Superfície/métodos , Grafite/química , Humanos , Óxidos/química , Fósforo/química , Elementos de Transição/química
6.
Molecules ; 26(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34361791

RESUMO

As a key enzyme regulating postprandial blood glucose, α-Glucosidase is considered to be an effective target for the treatment of diabetes mellitus. In this study, a simple, rapid, and effective method for enzyme inhibitors screening assay was established based on α-glucosidase catalyzes reactions in a personal glucose meter (PGM). α-glucosidase catalyzes the hydrolysis of maltose to produce glucose, which triggers the reduction of ferricyanide (K3[Fe(CN)6]) to ferrocyanide (K4[Fe(CN)6]) and generates the PGM detectable signals. When the α-glucosidase inhibitor (such as acarbose) is added, the yield of glucose and the readout of PGM decreased accordingly. This method can achieve the direct determination of α-glucosidase activity by the PGM as simple as the blood glucose tests. Under the optimal experimental conditions, the developed method was applied to evaluate the inhibitory activity of thirty-four small-molecule compounds and eighteen medicinal plants extracts on α-glucosidase. The results exhibit that lithospermic acid (52.5 ± 3.0%) and protocatechualdehyde (36.8 ± 2.8%) have higher inhibitory activity than that of positive control acarbose (31.5 ± 2.5%) at the same final concentration of 5.0 mM. Besides, the lemon extract has a good inhibitory effect on α-glucosidase with a percentage of inhibition of 43.3 ± 3.5%. Finally, the binding sites and modes of four active small-molecule compounds to α-glucosidase were investigated by molecular docking analysis. These results indicate that the PGM method is feasible to screening inhibitors from natural products with simple and rapid operations.


Assuntos
Benzaldeídos/farmacologia , Benzofuranos/farmacologia , Glicemia/análise , Catecóis/farmacologia , Depsídeos/farmacologia , Diabetes Mellitus Tipo 2/diagnóstico , Inibidores de Glicosídeo Hidrolases/farmacologia , Monitorização Ambulatorial/métodos , alfa-Glucosidases/sangue , Acarbose/química , Acarbose/farmacologia , Benzaldeídos/química , Benzaldeídos/isolamento & purificação , Benzofuranos/química , Benzofuranos/isolamento & purificação , Sítios de Ligação , Técnicas Biossensoriais/instrumentação , Catecóis/química , Catecóis/isolamento & purificação , Depsídeos/química , Depsídeos/isolamento & purificação , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores de Glicosídeo Hidrolases/química , Humanos , Hidrólise , Cinética , Maltose/metabolismo , Simulação de Acoplamento Molecular , Monitorização Ambulatorial/instrumentação , Extratos Vegetais/química , Plantas Medicinais , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Termodinâmica , Dispositivos Eletrônicos Vestíveis , alfa-Glucosidases/química
7.
Appl Opt ; 60(17): 5161-5168, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34143085

RESUMO

A surface plasmon resonance (SPR) sensor based on blue phosphorus (BlueP)/transition metal dichalcogenides (TMDCs) of two-dimensional (2D) materials is proposed to increase the performance. In this sensor, BlueP/TMDCs are coated on indium tin oxide (ITO) and different metals (Au/Ag/Cu) to improve the sensitivity. By optimizing structural parameters, with the BlueP/WS2 monolayer and Au thin film, the angular sensitivity can reach as high as 226.0°/RIU. The phase sensitivity also can be as high as 3.6001×106deg/RIU with BlueP/MoS2 4 layers, 228 nm ITO, and 25 nm Au thin film, which is 6.77 times that of the Au-ITO structure and 54.40 times that of the traditional SPR of Au thin film. The SPR sensor has potential applications in disease diagnosis, drug development, gene sequencing and treatment, environmental monitoring, food safety testing, doping testing, and other fields.


Assuntos
Técnicas Biossensoriais/instrumentação , Nanoestruturas/química , Fósforo/química , Ressonância de Plasmônio de Superfície/métodos , Compostos de Estanho/química , Elementos de Transição/química , Sensibilidade e Especificidade
8.
JAMA ; 325(22): 2273-2284, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34077502

RESUMO

Importance: Continuous glucose monitoring (CGM) is recommended for patients with type 1 diabetes; observational evidence for CGM in patients with insulin-treated type 2 diabetes is lacking. Objective: To estimate clinical outcomes of real-time CGM initiation. Design, Setting, and Participants: Exploratory retrospective cohort study of changes in outcomes associated with real-time CGM initiation, estimated using a difference-in-differences analysis. A total of 41 753 participants with insulin-treated diabetes (5673 type 1; 36 080 type 2) receiving care from a Northern California integrated health care delivery system (2014-2019), being treated with insulin, self-monitoring their blood glucose levels, and having no prior CGM use were included. Exposures: Initiation vs noninitiation of real-time CGM (reference group). Main Outcomes and Measures: Ten end points measured during the 12 months before and 12 months after baseline: hemoglobin A1c (HbA1c); hypoglycemia (emergency department or hospital utilization); hyperglycemia (emergency department or hospital utilization); HbA1c levels lower than 7%, lower than 8%, and higher than 9%; 1 emergency department encounter or more for any reason; 1 hospitalization or more for any reason; and number of outpatient visits and telephone visits. Results: The real-time CGM initiators included 3806 patients (mean age, 42.4 years [SD, 19.9 years]; 51% female; 91% type 1, 9% type 2); the noninitiators included 37 947 patients (mean age, 63.4 years [SD, 13.4 years]; 49% female; 6% type 1, 94% type 2). The prebaseline mean HbA1c was lower among real-time CGM initiators than among noninitiators, but real-time CGM initiators had higher prebaseline rates of hypoglycemia and hyperglycemia. Mean HbA1c declined among real-time CGM initiators from 8.17% to 7.76% and from 8.28% to 8.19% among noninitiators (adjusted difference-in-differences estimate, -0.40%; 95% CI, -0.48% to -0.32%; P < .001). Hypoglycemia rates declined among real-time CGM initiators from 5.1% to 3.0% and increased among noninitiators from 1.9% to 2.3% (difference-in-differences estimate, -2.7%; 95% CI, -4.4% to -1.1%; P = .001). There were also statistically significant differences in the adjusted net changes in the proportion of patients with HbA1c lower than 7% (adjusted difference-in-differences estimate, 9.6%; 95% CI, 7.1% to 12.2%; P < .001), lower than 8% (adjusted difference-in-differences estimate, 13.1%; 95% CI, 10.2% to 16.1%; P < .001), and higher than 9% (adjusted difference-in-differences estimate, -7.1%; 95% CI, -9.5% to -4.6%; P < .001) and in the number of outpatient visits (adjusted difference-in-differences estimate, -0.4; 95% CI, -0.6 to -0.2; P < .001) and telephone visits (adjusted difference-in-differences estimate, 1.1; 95% CI, 0.8 to 1.4; P < .001). Initiation of real-time CGM was not associated with statistically significant changes in rates of hyperglycemia, emergency department visits for any reason, or hospitalizations for any reason. Conclusions and Relevance: In this retrospective cohort study, insulin-treated patients with diabetes selected by physicians for real-time continuous glucose monitoring compared with noninitiators had significant improvements in hemoglobin A1c and reductions in emergency department visits and hospitalizations for hypoglycemia, but no significant change in emergency department visits or hospitalizations for hyperglycemia or for any reason. Because of the observational study design, findings may have been susceptible to selection bias.


Assuntos
Técnicas Biossensoriais/métodos , Automonitorização da Glicemia/métodos , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 2/sangue , Adulto , Técnicas Biossensoriais/instrumentação , Automonitorização da Glicemia/estatística & dados numéricos , Intervalos de Confiança , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Feminino , Hemoglobinas Glicadas/análise , Necessidades e Demandas de Serviços de Saúde/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Humanos , Hiperglicemia/sangue , Hiperglicemia/diagnóstico , Hiperglicemia/epidemiologia , Hipoglicemia/sangue , Hipoglicemia/diagnóstico , Hipoglicemia/epidemiologia , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Números Necessários para Tratar , Pontuação de Propensão , Estudos Retrospectivos , Viés de Seleção , Fatores de Tempo , Resultado do Tratamento
9.
Mikrochim Acta ; 188(6): 185, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33977395

RESUMO

An abdominal aortic aneurysm (AAA) is abnormal swelling in the abdominal aorta and a prevalent life-threatening disease. This research introduces a new interdigitated microelectrode (IDME)-sensing surface modified by iron oxide nanoworms (IONWs) for detecting the AAA biomarker insulin-like growth factor-1 (IGF1). A sandwich pattern was formulated with the IGF1 aptamer and IGFBP1 (IGF binding protein-1) on the IONW-constructed IDME hybrid to identify IGF1. The surface morphology of the IONWs revealed a uniform distribution of worm-like structures (80-100 nm) as confirmed by FESEM and FETEM analyses. Further, the presence of the major elements, Fe and O, was confirmed by EDX and XPS studies. The crystal planes that appeared in the IONW reflect cubic magnetite. IONW-modified IDME attained a limit of detection for IGF1 of 1 fM (3σ) with an aptamer-IGF1-IGFBP1 sandwich. This sandwich with IGFBP1 enhanced the current level at all concentrations of IGF1 and displayed linearity in the range 1 fM to 100 pM with a determination coefficient of R2 = 0.9373 [y = 3.38221x - 4.79]. Control experiments with complementary aptamer sequences, IGF2 and IGFBP3 did not show notable signal changes, indicating the specific detection of IGF1. This IONW constructed electrode helps to achieve the detection of low amounts of IGF1 and diagnose AAA at the stage prior to rupture.


Assuntos
Aneurisma da Aorta Abdominal/diagnóstico , Fator de Crescimento Insulin-Like I/análise , Nanoestruturas/química , Aneurisma da Aorta Abdominal/sangue , Aptâmeros de Nucleotídeos/química , Biomarcadores/sangue , Biomarcadores/química , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Compostos Ferrosos/química , Humanos , Ácidos Nucleicos Imobilizados/química , Fator de Crescimento Insulin-Like I/química , Limite de Detecção , Microeletrodos
10.
Sci Rep ; 11(1): 8231, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33859208

RESUMO

This proposal investigates the effect of vegetation height and density on received signal strength between two sensor nodes communicating under IEEE 802.15.4 wireless standard. With the aim of investigating the path loss coefficient of 2.4 GHz radio signal in an IEEE 802.15.4 precision agriculture monitoring infrastructure, measurement campaigns were carried out in different growing stages of potato and wheat crops. Experimental observations indicate that initial node deployment in the wheat crop experiences network dis-connectivity due to increased signal attenuation, which is due to the growth of wheat vegetation height and density in the grain-filling and physical-maturity periods. An empirical measurement-based path loss model is formulated to identify the received signal strength in different crop growth stages. Further, a NSGA-II multi-objective evolutionary computation is performed to generate initial node deployment and is optimized over increased coverage, reduced over-coverage, and received signal strength. The results show the development of a reliable wireless sensor network infrastructure for wheat crop monitoring.


Assuntos
Agricultura , Algoritmos , Monitorização de Parâmetros Ecológicos/métodos , Solanum tuberosum/genética , Triticum/genética , Agricultura/instrumentação , Agricultura/métodos , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Redes de Comunicação de Computadores , Produtos Agrícolas/genética , Monitorização de Parâmetros Ecológicos/instrumentação , Meio Ambiente , Testes Genéticos/instrumentação , Testes Genéticos/métodos , Reprodutibilidade dos Testes , Solanum tuberosum/crescimento & desenvolvimento , Triticum/crescimento & desenvolvimento , Tecnologia sem Fio
11.
Mikrochim Acta ; 188(4): 138, 2021 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-33772377

RESUMO

An electrochemical sensor-based phosphorus-doped microporous carbon spheroidal structures (P-MCSs) has been designed for selective adrenaline (ADR) signaling in human blood serum. The P-MCS electrode sensor is built with heterogeneous surface alignments including multiple porous sizes with open holes and meso-/macro-grooves, rough surface curvatures, and integral morphology with interconnected and conjugated microspheres. In addition, the P atom-doped graphitic carbon forms highly active centers, increases charge mobility on the electrode surface, creates abundant active centers with facile functionalization, and induces binding to ADR molecules. The designed P-MCS electrode exhibits ultrasensitive monitoring of ADR with a low detection limit of 0.002 µM and high sensitivity of 4330 µA µM-1 cm-2. In addition, two electrochemical techniques, namely, square wave voltammetry (SWV) and chronoamperometry (CA), were used; these techniques achieve high stability, fast response, and a wide linear range from 0.01 to 6 µM. The sensing assays based on P-MCSs provide evidence of the formation of active interfacial surface-to-ADR binding sites, high electron diffusion, and heavy target loads along with/without a plane of spheroids. Thus, P-MCSs can be used for the routine monitoring of ADR in human blood serum, providing a fast response, and requiring highly economical materials at extremely low concentrations. Electrode surface modulation based on P-doped carbon spheres (P-MCS) exhibits high electrochemical activity with fast charge transport, multi-diffusible active centers, high loading of ADR, and facile molecular/electron diffusion at its surface. The P-MCS sensitively and selectively detects the ADR in human fluids and can be used for clinical investigation of some neuronal diseases such as Alzheimer diseases.


Assuntos
Carbono/química , Técnicas Eletroquímicas/métodos , Epinefrina/sangue , Adsorção , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/instrumentação , Eletrodos , Epinefrina/química , Humanos , Limite de Detecção , Oxirredução , Fósforo/química , Porosidade , Reprodutibilidade dos Testes
12.
Mikrochim Acta ; 188(4): 112, 2021 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-33675442

RESUMO

An electrochemical biosensor was prepared for nucleic acid-based hantavirus detection using a Cu-based metal-organic framework (CuMOF) as a signal tag. The CuMOF was synthesized by the solvothermal method and then covalently bonded with signal DNA (sDNA) probes. The Au nanoparticles and reduced graphene oxide composite were deposited on the electrode surface by electroreduction as support substrate and was then functionalized with capture DNA (cDNA) probes by self-assembly. Through the complementary base pairing, the target DNA (tDNA) fragment of hantavirus hybridized with the cDNA and the sDNA in a sandwich-type format. The tDNA was detected according to the current signal of the CuMOF catalyzed reaction using o-phenylenediamine as redox substrate. The peak current of the biosensor at - 0.55 V increased linearly in proportion to the logarithmic value of the tDNA concentration from 10-15 to 10-9 mol/L, with a detection limit of 0.74 × 10-15 mol/L. Moreover, the proposed biosensor was successfully applied to detect hantavirus and was able to distinguish hantavirus from other arboviruses.


Assuntos
Técnicas Biossensoriais/métodos , DNA Viral/análise , Técnicas Eletroquímicas/métodos , Grafite/química , Nanopartículas Metálicas/química , Orthohantavírus/química , Técnicas Biossensoriais/instrumentação , Cobre/química , DNA Complementar/química , DNA Complementar/genética , DNA Viral/genética , Técnicas Eletroquímicas/instrumentação , Eletrodos , Ouro/química , Limite de Detecção , Estruturas Metalorgânicas/química , Hibridização de Ácido Nucleico
13.
Nat Commun ; 12(1): 431, 2021 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-33462204

RESUMO

Neuronal exocytosis facilitates the propagation of information through the nervous system pertaining to bodily function, memory, and emotions. Using amperometry, the sub-millisecond dynamics of exocytosis can be monitored and the modulation of exocytosis due to drug treatment or neurodegenerative diseases can be studied. Traditional single-cell amperometry is a powerful technique for studying the molecular mechanisms of exocytosis, but it is both costly and labor-intensive to accumulate statistically significant data. To surmount these limitations, we have developed a silicon-based electrode array with 1024 on-chip electrodes that measures oxidative signal in 0.1 millisecond intervals. Using the developed device, we are able to capture the modulation of exocytosis due to Parkinson's disease treatment (L-Dopa), with statistical significance, within 30 total minutes of recording. The validation study proves our device's capability to accelerate the study of many pharmaceutical treatments for various neurodegenerative disorders that affect neurotransmitter secretion to a matter of minutes.


Assuntos
Técnicas Biossensoriais/instrumentação , Exocitose/fisiologia , Vesículas Extracelulares/metabolismo , Neurotransmissores/metabolismo , Linhagem Celular Tumoral , Humanos , Microeletrodos , Semicondutores
14.
Anal Bioanal Chem ; 413(1): 193-203, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33119785

RESUMO

Herein, a photoelectrochemical (PEC) aptasensing platform was designed by integrating surface oxygen vacancy (OV) defects, Ti3+ self-doping, the heterojunction, and resonance energy transfer (RET) effect into one platform for the detection of diclofenac sodium (DCF). Briefly, OV defects were introduced on TiO2 nanospheres with simultaneous Ti3+ self-doping, followed by a well-separated deposition of FeVO4 nanoparticles on TiO2 to obtain a Ti3+-O-TiO2/FeVO4 heterojunction. The surface modification of OVs, Ti3+ doping, and deposition of FeVO4 were confirmed by SEM, XPS, EPR, DRS, and PEC measurements. The surface OVs and doping of Ti3+ species created a new donor (defect) energy level under the conduction band of TiO2, which minimized the bandgap and thereby improved the visible light absorption of TiO2. Moreover, the capture of photo-excited electrons by surface OVs could hinder the electron-hole recombination. Due to the intimate surface contact and perfect energy matching between TiO2 and FeVO4, the formation of heterojunction decreased the bandgap and facilitated the electron-hole separation of TiO2. All these above events contributed to the enhancement of the PEC signals, which were then quenched by the RET effect between Ti3+-O-TiO2/FeVO4 and Au nanoparticle (AuNP)-labeled cDNA that had been attached to its complementary DCF aptamer on Ti3+-O-TiO2/FeVO4|ITO. The addition of target-DCF detached AuNP-labeled cDNA from the electrode to recover the photocurrent, resulting in a "signal-on" PEC aptasensor that exhibited a 0.1-500-nM linear range and a detection limit of 0.069 nM for DCF, attributed to the excellent amplification of the proposed aptasensing platform.


Assuntos
Anti-Inflamatórios não Esteroides/análise , Diclofenaco/análise , Técnicas Eletroquímicas/instrumentação , Ferro/química , Processos Fotoquímicos , Titânio/química , Vanadatos/química , Técnicas Biossensoriais/instrumentação , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Propriedades de Superfície
15.
Mikrochim Acta ; 187(11): 588, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33015730

RESUMO

Nanofabricated gold nanoparticles (Au-NPs) on MoS2 nanosheets (Au-NPs/MoS2) in back-gated field-effect transistor (BG-FET) are presented, which acts as an efficient semiconductor device for detecting a low concentration of C-reactive protein (C-RP). The decorated nanomaterials lead to an enhanced electron conduction layer on a 100-µm-sized transducing channel. The sensing surface was characterized by Raman spectroscopy, ultraviolet-visible spectroscopy (UV-Vis), atomic force microscopy (AFM), scanning electron microscopy (SEM), and high-power microscopy (HPM). The BG-FET device exhibits an excellent limit of detection of 8.38 fg/mL and a sensitivity of 176 nA/g·mL-1. The current study with Au-NPs/MoS2 BG-FET displays a new potential biosensing technology; especially for integration into complementary metal oxide (CMOS) technology for hand-held future device application.


Assuntos
Proteína C-Reativa/análise , Nanopartículas Metálicas/química , Nanocompostos/química , Transistores Eletrônicos , Anticorpos Imobilizados/imunologia , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Proteína C-Reativa/imunologia , Dissulfetos/química , Condutividade Elétrica , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Ouro/química , Humanos , Limite de Detecção , Molibdênio/química , Reprodutibilidade dos Testes
16.
Mikrochim Acta ; 187(9): 500, 2020 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-32803374

RESUMO

A novel "signal-on" electrochemical aptasensor was developed for ultrasensitive and specific detection of BPA, using single-walled carbon nanotubes (SWCNT) as the electro-catalytic probe for further signal amplification. The multi-walled carbon nanotubes (MWCNT), amino-functionalized magnetite, and gold nanoparticles (NH2-Fe3O4/Au NPs) were applied first to modify the glassy carbon electrode (GCE) surface and to form a nanomaterial film with satisfactory conductive properties, stability, and biocompatibility. The BPA aptamer was then loaded onto the sensing platform by hybridization with complementary DNA (CDNA). In the presence of BPA it combines with the aptamer and the BPA-aptamer conjugate was released from the electrode;subsequently the added SWCNT and CDNA assembled quickly. Thus, the dual-amplification of the "signal-on" electrochemical aptasensor takes effect. The [Fe (CN)6]3-/4- redox probe signal (∆I) detected by DPV (differential pulse voltammetry) is proportional to the negative logarithm of BPA concentration between 10-19 M and 10-14 M. The detection limit is 0.08 aM. Importantly, the proposed biosensor represents a successful application for determination of BPA in human serum and lake water. Schematic representation of SWCNT-amplified "signal-on" electrochemical aptasensor for the detection of trace level of bisphenol A in human serum and lake water.


Assuntos
Aptâmeros de Nucleotídeos/química , Compostos Benzidrílicos/sangue , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Nanotubos de Carbono/química , Fenóis/sangue , Sequência de Bases , Técnicas Biossensoriais/instrumentação , DNA/química , Técnicas Eletroquímicas/instrumentação , Eletrodos , Óxido Ferroso-Férrico/química , Ouro/química , Humanos , Ácidos Nucleicos Imobilizados/química , Lagos/análise , Limite de Detecção , Nanopartículas Metálicas/química , Reprodutibilidade dos Testes
17.
Anal Chem ; 92(18): 12528-12537, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32842739

RESUMO

An ever-growing demand for uranium in various industries raises concern for human health of both occupationally exposed personnel and the general population. Toxicological effects related to uranium (natural, enriched, or depleted uranium) intake involve renal, pulmonary, neurological, skeletal, and hepatic damage. Absorbed uranium is filtered by the kidneys and excreted in the urine, thus making uranium detection in urine a primary indication for exposure and body burden assessment. Therefore, the detection of uranium contamination in bio-samples (urine, blood, saliva, etc.,) is of crucial importance in the field of occupational exposure and human health-related applications, as well as in nuclear forensics. However, the direct determination of uranium in bio-samples is challenging because of "ultra-low" concentrations of uranium, inherent matrix complexity, and sample diversity, which pose a great analytical challenge to existing detection methods. Here, we report on the direct, real-time, sensitive, and selective detection of uranyl ions in unprocessed and undiluted urine samples using a uranyl-binding aptamer-modified silicon nanowire-based field-effect transistor (SiNW-FET) biosensor, with a detection limit in the picomolar concentration range. The aptamer-modified SiNW-FET presented in this work enables the simple and sensitive detection of uranyl in urine samples. The experimental approach has a straight-forward implementation to other metals and toxic elements, given the availability of target-specific aptamers. Combining the high surface-to-volume ratio of SiNWs, the high affinity and selectivity of the uranyl-binding aptamer, and the distinctive sensing methodology gives rise to a practical platform, offering simple and straightforward sensing of uranyl levels in urine, suitable for field deployment and point-of-care applications.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais , Nanofios , Silício/química , Transistores Eletrônicos , Urânio/urina , Técnicas Biossensoriais/instrumentação , Dimetilpolisiloxanos/química , Humanos , Dispositivos Lab-On-A-Chip
18.
Biosens Bioelectron ; 165: 112356, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32510339

RESUMO

Circle-to-circle amplification (C2CA) is a specific and precise cascade nucleic acid amplification method consisting of more than one round of padlock probe ligation and rolling circle amplification (RCA). Although C2CA provides a high amplification efficiency with a negligible increase of false-positive risk, it contains several step-by-step operation processes. We herein demonstrate a homogeneous and isothermal nucleic acid quantification strategy based on C2CA and optomagnetic analysis of magnetic nanoparticle (MNP) assembly. The proposed homogeneous circle-to-circle amplification eliminates the need for additional monomerization and ligation steps after the first round of RCA, and combines two amplification rounds in a one-pot reaction. The second round of RCA produces amplicon coils that anneal to detection probes grafted onto MNPs, resulting in MNP assembly that can be detected in real-time using an optomagnetic sensor. The proposed methodology was applied for the detection of a synthetic complementary DNA of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2, also known as 2019-nCoV) RdRp (RNA-dependent RNA polymerase) coding sequence, achieving a detection limit of 0.4 fM with a dynamic detection range of 3 orders of magnitude and a total assay time of ca. 100 min. A mathematical model was set up and validated to predict the assay performance. Moreover, the proposed method was specific to distinguish SARS-CoV and SARS-CoV-2 sequences with high similarity.


Assuntos
Betacoronavirus/isolamento & purificação , Técnicas Biossensoriais/instrumentação , Infecções por Coronavirus/diagnóstico , DNA Complementar/análise , Técnicas de Amplificação de Ácido Nucleico/instrumentação , Pneumonia Viral/diagnóstico , Técnicas Biossensoriais/métodos , COVID-19 , Desenho de Equipamento , Estudos de Viabilidade , Humanos , Limite de Detecção , Magnetismo/instrumentação , Magnetismo/métodos , Nanopartículas de Magnetita/química , Técnicas de Amplificação de Ácido Nucleico/métodos , Pandemias , SARS-CoV-2
19.
Anal Bioanal Chem ; 412(17): 3975-3982, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32372275

RESUMO

In vivo, drug molecules interact with their biological targets (e.g., enzymes, receptors, ion channels, transporters), thereby eliciting therapeutic effects. Assays that measure the interaction between drugs and bio-targets may be used as drug biosensors, which are capable of broadly detecting entire drug classes without prior knowledge of their chemical structure. This Trends article covers recent developments in bio-target-based screening assays for detecting drugs associated with the following areas: illicit products marketed as dietary supplements, food-producing animals, and bodily fluids. General challenges and considerations associated with using bio-target assays are also presented. Finally, future applications of these assays for drug detection are suggested based upon current needs.


Assuntos
Técnicas Biossensoriais/métodos , Suplementos Nutricionais/análise , Drogas Ilícitas/análise , Preparações Farmacêuticas/análise , Animais , Técnicas Biossensoriais/instrumentação , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Humanos , Detecção do Abuso de Substâncias/instrumentação , Detecção do Abuso de Substâncias/métodos , Drogas Veterinárias/análise
20.
Biosens Bioelectron ; 162: 112273, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32452396

RESUMO

Cardiac arrhythmia and drug-induced cardiotoxicity seriously threaten the human life. To develop antiarrhythmic agents and prevent the drug-induced cardiotoxicity, it is demanded to explore the high-specificity and high-efficiency drug screening platforms for preclinical investigations. Here, a specific electromechanical integrated correlation (EMIC) model was established based on the synchronized signal recording of cardiomyocyte-based biosensing system. The cardiomyocyte-based biosensing system consists of an integrated electromechanical device and a synchronized recording instrument. By extracting the feature points and correlation information of both electrical and mechanical signals, the multi-parameters of EMIC are applied for the drug recognition, showing the good specificity to analyze the typical Na+, K+, Ca2+ channel blockers. Further, visualized analysis of EMIC parameters was performed using the extracted parameters of synchronized recording signals to present the drug specific recognition functions. By heat map, radar map, and principal component analysis (PCA), the specific features and patterns were intuitively displayed to achieve the drug recognition. We believe this high-content and high-specific drug recognition strategy will be a promising and alternative method for the preclinical screening of cardiac safety and drug development in biomedical fields.


Assuntos
Avaliação Pré-Clínica de Medicamentos/instrumentação , Técnicas Eletroquímicas/instrumentação , Canais Iônicos/antagonistas & inibidores , Miócitos Cardíacos/efeitos dos fármacos , Técnicas Biossensoriais/instrumentação , Linhagem Celular , Desenho de Equipamento , Humanos , Canais Iônicos/metabolismo , Miócitos Cardíacos/metabolismo
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