Fundamentals, achievements and challenges in the electrochemical sensing of pathogens

Printed circuit boards (PCBs) offer a promising platform for the development of electronics-assisted biomedical diagnostic sensors and microsystems. The long-standing industrial basis offers distinctive advantages for cost-effective, reproducible, and easily integrated sample-in-answer-out diagnostic microsystems. Nonetheless, the commercial techniques used in the fabrication of PCBs produce various contaminants potentially degrading severely their stability and repeatability in electrochemical sensing applications. Herein, we analyse for the first time such critical technological considerations, allowing the exploitation of commercial PCB platforms as reliable electrochemical sensing platforms. The presented electrochemical and physical characterisation data reveal clear evidence of both organic and inorganic sensing electrode surface contaminants, which can be removed using various pre-cleaning techniques. We demonstrate that, following such pre-treatment rules, PCB-based electrodes can be reliably fabricated for sensitive electrochemical biosensors. Herein, we demonstrate the applicability of the methodology both for labelled protein (procalcitonin) and label-free nucleic acid (E. coli-specific DNA) biomarker quantification, with observed limits of detection (LoD) of 2 pM and 110 pM, respectively. The proposed optimisation of surface pre-treatment is critical in the development of robust and sensitive PCB-based electrochemical sensors for both clinical and environmental diagnostics and monitoring applications.

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Molecularly Imprinted Polymers Combined with Electrochemical Sensors for Food Contaminants Analysis

Molecules ◽

10.3390/molecules26154607 ◽

2021 ◽

Vol 26 (15) ◽

pp. 4607

Author(s):

Dounia Elfadil ◽

Abderrahman Lamaoui ◽

Flavio Della Pelle ◽

Aziz Amine ◽

Dario Compagnone

Keyword(s):

Food Safety ◽

Molecularly Imprinted Polymers ◽

Electrochemical Sensors ◽

Low Cost ◽

Electrochemical Analysis ◽

Ease Of Use ◽

Electrochemical Sensing ◽

Food Contaminants ◽

Molecularly Imprinted ◽

Imprinted Polymers

Detection of relevant contaminants using screening approaches is a key issue to ensure food safety and respect for the regulatory limits established. Electrochemical sensors present several advantages such as rapidity; ease of use; possibility of on-site analysis and low cost. The lack of selectivity for electrochemical sensors working in complex samples as food may be overcome by coupling them with molecularly imprinted polymers (MIPs). MIPs are synthetic materials that mimic biological receptors and are produced by the polymerization of functional monomers in presence of a target analyte. This paper critically reviews and discusses the recent progress in MIP-based electrochemical sensors for food safety. A brief introduction on MIPs and electrochemical sensors is given; followed by a discussion of the recent achievements for various MIPs-based electrochemical sensors for food contaminants analysis. Both electropolymerization and chemical synthesis of MIP-based electrochemical sensing are discussed as well as the relevant applications of MIPs used in sample preparation and then coupled to electrochemical analysis. Future perspectives and challenges have been eventually given.

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Development of Au-Pd@UiO-66-on-ZIF-L/CC as a self-supported electrochemical sensor for in situ monitoring of cellular hydrogen peroxide

Journal of Materials Chemistry B ◽

10.1039/d1tb01120k ◽

2021 ◽

Author(s):

Jilin Zheng ◽

Peng Zhao ◽

Shiying Zhou ◽

Sha Chen ◽

Yi Liang ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Electrochemical Sensor ◽

Noble Metals ◽

Electrochemical Sensors ◽

Metal Organic Frameworks ◽

Electrochemical Sensing ◽

In Situ Monitoring ◽

Metal Organic

Integrating metal-organic frameworks (MOFs) of different components or structures together and exploiting them as electrochemical sensors for electrochemical sensing have aroused great interest. And the incorporation of noble metals with...

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Nanowire Modification to Enhance the Performance of Neurotransmitter Sensors

Journal of Nanotechnology in Engineering and Medicine ◽

10.1115/1.4002500 ◽

2010 ◽

Vol 1 (4) ◽

Cited By ~ 4

Author(s):

Hung Cao ◽

J.-C. Chiao

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Electrochemical Sensors ◽

Electrochemical Sensing ◽

Human Central Nervous System ◽

Excitatory Neurotransmitter ◽

Modification Method ◽

Solid Liquid ◽

Scanning Electron ◽

Si Wafer

In this work, we have developed a method to modify the platinum (Pt) working electrode with nanowires using vapor-solid-liquid (VLS) mechanism in order to increase the sensitivity of our microelectrochemical neurotransmitter sensors. Our sensor probes were manufactured from a 300 μm thick silicon (Si) wafer with several electrode designs for implantation in various locations of the human central nervous system. The surfaces of electrodes were observed and characterized by scanning electron microscopy (SEM) and cyclic voltammetry (CV). The complete devices were made and used to demonstrate the enhancement in performance contributed by nanowires in the enzyme-based electrochemical sensing of L-glutamate, which is the most abundant excitatory neurotransmitter. Comparison between electrodes with and without nanowire modification was conducted, showing that the modification method is a good option to improve the performance of electrochemical sensors.

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An Electrochemical Sensor Based on Gold Nanodendrite/Surfactant Modified Electrode for Bisphenol A Detection

Journal of Analytical Methods in Chemistry ◽

10.1155/2020/6693595 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Nguyen Thi Lien ◽

Le Quoc Hung ◽

Nguyen Tien Hoang ◽

Vu Thi Thu ◽

Dau Thi Ngoc Nga ◽

...

Keyword(s):

Bisphenol A ◽

Electrochemical Sensors ◽

Differential Pulse ◽

Electrochemical Sensing ◽

Fluorescence Measurements ◽

Sensing Platform ◽

Electrochemical Window ◽

Galvanostatic Deposition ◽

Bisphenol A Detection ◽

Good Agreement

In the present work, we reported the simple way to fabricate an electrochemical sensing platform to detect Bisphenol A (BPA) using galvanostatic deposition of Au on a glassy carbon electrode covered by cetyltrimethylammonium bromide (CTAB). This material (CTAB) enhances the sensitivity of electrochemical sensors with respect to the detection of BPA. The electrochemical response of the modified GCE to BPA was investigated by cyclic voltammetry and differential pulse voltammetry. The results displayed a low detection limit (22 nm) and a linear range from 0.025 to 10 µm along side with high reproducibility (RSD = 4.9% for seven independent sensors). Importantly, the prepared sensors were selective enough against interferences with other pollutants in the same electrochemical window. Notably, the presented sensors have already proven their ability in detecting BPA in real plastic water drinking bottle samples with high accuracy (recovery range = 96.60%–102.82%) and it is in good agreement with fluorescence measurements.

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Portable Data Acquisition System for Nano and Ultra-Micro Scale Electrochemical Sensors

10.26434/chemrxiv.12320291 ◽

2020 ◽

Author(s):

Alan O'Riordan ◽

Ian Seymour ◽

Aidan Murphy ◽

Ivan O'Connell

Keyword(s):

Data Acquisition ◽

River Water ◽

Electrochemical Sensors ◽

Full Range ◽

Data Acquisition System ◽

Water Quality Monitoring ◽

Electrochemical Sensing ◽

Acquisition System ◽

Micro Scale ◽

Point Of Use

This work describes a flexible and portable data acquisition system that has been developed to interface to nano and ultra-micro scale electrochemical sensors at the point of use. It can perform a range of voltammetric tests, including Cyclic Voltammetry, Square Wave Voltammetry and Generator Collector Voltammetery. The data acquisition system interfaces to a smartphone, operates from a rechargeable battery and is of suitable form factor to ensure that it’s fully portable. By utilising commercially available components, this system has been developed to lower the barrier for entry for the development of emerging portable electrochemical sensing technologies at micro and nano scale. To show the full range of functionality of the system, a use case involving river water quality monitoring is presented through generation of a calibration curve, using a recently developed Tyndall National Institute ultra-microband electrochemical sensor, for the detection of dissolved oxygen in river water.

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Application of Carbon Nanomaterials Decorated Electrochemical Sensor for Analysis of Environmental Pollutants

10.5772/intechopen.96538 ◽

2021 ◽

Author(s):

Sunil Kumar ◽

Abhay Nanda Srivastva

Keyword(s):

Carbon Nanotubes ◽

Carbon Nanomaterials ◽

Electrochemical Sensors ◽

Anodic Stripping Voltammetry ◽

Environmental Pollutants ◽

Stripping Voltammetry ◽

Metal Electrode ◽

Effective Area ◽

Electrochemical Sensing ◽

Working Electrode

Carbon nanomaterials (CNMs), especially carbon nanotubes and graphene, have been attracting tremendous attention in environmental analysis for rapid and cost effective detection of various analytes by electrochemical sensing. CNMs can increase the electrode effective area, enhance the electron transfer rate between the electrode and analytes, and/or act as catalysts to increase the efficiency of electrochemical reaction, detection, adsorption and removal are of great significance. Various carbon nanomaterials including carbon nanotubes, graphene, mesoporous carbon, carbon dots exhibited high adsorption and detection capacity. Carbon and its derivatives possess excellent electro catalytic properties for the modified sensors, electrochemical methods usually based on anodic stripping voltammetry at some modified carbon electrodes. Metal electrode detection sensitivity is enhanced through surface modification of working electrode (GCE). Heavy metals have the defined redox potential. A remarkable deal of efficiency with the electrochemical sensors can be succeeded by layering the surface of the working electrode with film of active electro-catalytic species. Usually, electro catalysts used for fabrication of sensors are surfactants, nano-materials, polymers, carbon-based materials, organic ligands and biomaterials.

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Application of biosynthesized metal nanoparticles in electrochemical sensors

Journal of the Serbian Chemical Society ◽

10.2298/jsc200521077d ◽

2021 ◽

pp. 77-77

Author(s):

Totka Dodevska ◽

Dobrin Hadzhiev ◽

Ivan Shterev ◽

Yanna Lazarova

Keyword(s):

Green Synthesis ◽

Metal Nanoparticles ◽

Electrochemical Sensors ◽

Dynamic Range ◽

Limit Of Detection ◽

Cost Effective ◽

Electrochemical Sensing ◽

Synthesis Methods ◽

Range Limit ◽

Wide Range

Recently, the development of eco-friendly, cost-effective and reliable methods for synthesis of metal nanoparticles has drawn a considerable attention. The so-called green synthesis, using mild reaction conditions and natural resources as plant extracts and microorganisms, has established as a convenient, sustainable, cheap and environmentally safe approach for synthesis of a wide range of nanomaterials. Over the past decade, biosynthesis is regarded as an important tool for reducing the harmful effects of traditional nanoparticle synthesis methods commonly used in laboratories and industry. This review emphasizes the significance of biosynthesized metal nanoparticles in the field of electrochemical sensing. There is increasing evidence that green synthesis of nanoparticles provides a new direction in designing of cost-effective, highly sensitive and selective electrode-catalysts applicable in food, clinical and environmental analysis. The article is based on 157 references and provided a detailed overview on the main approaches for green synthesis of metal nanoparticles and their applications in designing of electrochemical sensor devices. Important operational characteristics including sensitivity, dynamic range, limit of detection, as well as data on stability and reproducibility of sensors have also been covered. Keywords: biosynthesis; green synthesis; nanomaterials; nanotechnology; modified electrodes

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Preparation and Characterization of Carbon Xerogel Based Composites for Electrochemical Sensing and Photocatalytic Degradation

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2021.18963 ◽

2021 ◽

Vol 21 (4) ◽

pp. 2323-2333

Author(s):

Carmen I. Fort ◽

Mihai M. Rusu ◽

Lucian C. Pop ◽

Liviu C. Cotet ◽

Adriana Vulpoi ◽

...

Keyword(s):

Electron Microscopy ◽

Photocatalytic Degradation ◽

Electrochemical Sensors ◽

Sol Gel ◽

Nanocomposite Material ◽

Electrochemical Sensing ◽

Ambient Conditions ◽

Carbon Xerogel ◽

Voltammetric Detection

In order to obtain a multifunctional nanocomposite material-for electrochemical sensors and photocatalytic applications, structures based on Bi, Fe and TiO2 were grown inside carbon xerogel supports (BiFeCX and BiFeCX-TiO2). First, a wet polymer containing Bi and Fe salts was obtained by following a modified resorcinol-formaldehyde based sol–gel route, followed by drying in ambient conditions, and pyrolysis under inert atmosphere. Then, through TiCl4 hydrolysis, TiO2 nanoparticles were deposited on the BiFeCX xerogel leading to BiFeCX-TiO2. The morphological and structural characterization of the investigated nanocomposites consisted in X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy and N2 adsorption measurements, revealing porous carbon structures with embedded nanoparticles and the particularities driven by the pyrolysis and TiCl4 treatment. The new modified electrodes based on BiFeCX or BiFeCX-TiO2 nanocomposite materials, kept in a chitosan matrix (Chi) and deposited on a glassy carbon (GC) electrode surface (GC/Chi-BiFeCX or GC/Chi-BiFeCX-TiO2), were obtained and investigated for Pb(II) voltammetric detection and H2O2 amperometric detection. Moreover, the BiFeCX-TiO2 nanocomposite was tested for the photocatalytic degradation of methyl orange. The great potential of BiFeCX nanocomposite material for developing electrochemical sensors, or BiFeCX-TiO2 for sensors application and photocatalytic application was demonstrated.

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Nanoelectrode Arrays Fabricated by Thermal Nanoimprint Lithography for Biosensing Application

Biosensors ◽

10.3390/bios10080090 ◽

2020 ◽

Vol 10 (8) ◽

pp. 90

Author(s):

Alessandra Zanut ◽

Alessandro Cian ◽

Nicola Cefarin ◽

Alessandro Pozzato ◽

Massimo Tormen

Keyword(s):

Nanoimprint Lithography ◽

Electrochemical Sensors ◽

Low Cost ◽

Scale Up ◽

Electrochemical Sensing ◽

Electrical Measurements ◽

Boron Doped Diamond ◽

Sensing Platform ◽

Increased Sensitivity ◽

Gliadin Protein

Electrochemical sensors are devices capable of detecting molecules and biomolecules in solutions and determining the concentration through direct electrical measurements. These systems can be miniaturized to a size less than 1 µm through the creation of small-size arrays of nanoelectrodes (NEA), offering advantages in terms of increased sensitivity and compactness. In this work, we present the fabrication of an electrochemical platform based on an array of nanoelectrodes (NEA) and its possible use for the detection of antigens of interest. NEAs were fabricated by forming arrays of nanoholes on a thin film of polycarbonate (PC) deposited on boron-doped diamond (BDD) macroelectrodes by thermal nanoimprint lithography (TNIL), which demonstrated to be a highly reliable and reproducible process. As proof of principle, gliadin protein fragments were physisorbed on the polycarbonate surface of NEAs and detected by immuno-indirect assay using a secondary antibody labelled with horseradish peroxidase (HRP). This method allows a successful detection of gliadin, in the range of concentration of 0.5–10 μg/mL, by cyclic voltammetry taking advantage from the properties of NEAs to strongly suppress the capacitive background signal. We demonstrate that the characteristics of the TNIL technology in the fabrication of high-resolution nanostructures together with their low-cost production, may allow to scale up the production of NEAs-based electrochemical sensing platform to monitor biochemical molecules for both food and biomedical applications.

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