Developing high-sensitivity ethanol liquid sensors based on ZnO/porous Si nanostructure surfaces using an electrochemical impedance technique

In this work, the Ag@Cu particles with yolk–shell nanostructure was prepared by facile solvothermal method, which was modified on glassy carbon electrode (GCE) to fabricate electrochemical sensor for the convenient and fast determination of p-aminobenzoic acid (PABA). The surface morphology and electrochemical properties of the as-prepared Ag@Cu nanocomposite modified electrode were characterized by scanning electron microscopy, transmission electron microscopy, chronocoulometry, and electrochemical impedance spectroscopy. Further, the electrochemical sensing of PABA was performed on the Ag@Cu/GCE using cyclic voltammetry and differential pulse voltammetry techniques, showing high catalytic activity. Under the optimal conditions, the sensor exhibited a wide linear range, high sensitivity, and low detection limit of 0.315 μmol/L for PABA. The developed sensor was also successfully applied for PABA detection in anesthetic and cosmetics with satisfactory results.

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Determination of Uric Acid in Biological Fluids by Ceria Nanoparticles Doped Reduced Graphene Oxide Nanocomposite Voltammetric Sensor

Journal of The Electrochemical Society ◽

10.1149/1945-7111/ac4376 ◽

2021 ◽

Author(s):

Peihong Deng ◽

Jinxia Feng ◽

Jingyun Xiao ◽

Yanping Wei ◽

Jinsong Zuo ◽

...

Keyword(s):

Electron Microscopy ◽

Uric Acid ◽

Electrochemical Impedance ◽

Kidney Diseases ◽

Biological Fluids ◽

Neurological Diseases ◽

High Sensitivity ◽

Ceria Nanoparticles ◽

Structure And Property ◽

Reduced Graphene

Abstract High levels of uric acid (UA) in the human body usually cause diabetes, hypertension and atherosclerosis, kidney diseases, and neurological diseases. Hence, it is important to develop sensitive methods for UA determination. In this paper, nanocomposite composed of ceria nanoparticles and reduced graphene was successfully modified on the surface of glassy carbon electrode (ceria NPs-rGO/GCE) by a simple electroreduction method. The morphology, structure and property of the ceria NPs-rGO/GCE was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The electrocatalytic activity of the ceria NPs-rGO/GCE for uric acid (UA) oxidation was studied in detail. The results showed that the ceria NPs-rGO/GCE exhibited excellent selectivity and high sensitivity for UA detection. In 0.05 M H2SO4 solution, a linear range of 0.02-20 M and a low detection limit of 8.0 nM of UA were obtained on the ceria NPs-rGO/GCE. This developed method was successfully applied for the detection of UA in human serum and urine samples, and its recoveries reached 95.8%-105.0%.

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Performance Evaluation of Crack-Like ZnO/PSi Nanostructure Chemical Solution Sensor via Electrochemical Impedance Technique

Journal of The Electrochemical Society ◽

10.1149/1945-7111/ab6970 ◽

2020 ◽

Vol 167 (2) ◽

pp. 027520

Author(s):

F. S. Husairi ◽

K. A. Eswar ◽

N. A. Asib ◽

Muliyadi Guliling ◽

M. Rusop ◽

...

Keyword(s):

Performance Evaluation ◽

Electrochemical Impedance ◽

Chemical Solution ◽

Impedance Technique

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Diazonium-Modified Screen-Printed Electrodes for Immunosensing Growth Hormone in Blood Samples

Biosensors ◽

10.3390/bios9030088 ◽

2019 ◽

Vol 9 (3) ◽

pp. 88 ◽

Cited By ~ 1

Author(s):

Nan Li ◽

Ari M. Chow ◽

Hashwin V. S. Ganesh ◽

Melanie Ratnam ◽

Ian R. Brown ◽

...

Keyword(s):

Growth Hormone ◽

Photoelectron Spectroscopy ◽

Electrochemical Impedance ◽

Low Cost ◽

High Sensitivity ◽

Sample Volume ◽

Screening Methods ◽

Serum Samples ◽

Potential Applicability ◽

Screen Printed

Altered growth hormone (GH) levels represent a major global health challenge that would benefit from advances in screening methods that are rapid and low cost. Here, we present a miniaturized immunosensor using disposable screen-printed carbon electrodes (SPCEs) for the detection of GH with high sensitivity. The diazonium-based linker layer was electrochemically deposited onto SPCE surfaces, and subsequently activated using covalent agents to immobilize monoclonal anti-GH antibodies as the sensing layer. The surface modifications were monitored using contact angle measurements and X-ray photoelectron spectroscopy (XPS). The dissociation constant, Kd, of the anti-GH antibodies was also determined as 1.44 (±0.15) using surface plasmon resonance (SPR). The immunosensor was able to detect GH in the picomolar range using a 20 µL sample volume in connection with electrochemical impedance spectroscopy (EIS). The selectivity of the SPCE-based immunosensors was also challenged with whole blood and serum samples collected at various development stages of rats, demonstrating the potential applicability for detection in biological samples. Our results demonstrated that SPCEs provided the development of low-cost and single-use electrochemical immunosensors in comparison with glassy carbon electrode (GCE)-based ones.

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Impedance Sensing Platform for Detection of the Food Pathogen Listeria monocytogenes

Electronics ◽

10.3390/electronics7120347 ◽

2018 ◽

Vol 7 (12) ◽

pp. 347 ◽

Cited By ~ 11

Author(s):

Maria Chiriacò ◽

Ilaria Parlangeli ◽

Fausto Sirsi ◽

Palmiro Poltronieri ◽

Elisabetta Primiceri

Keyword(s):

Listeria Monocytogenes ◽

Foodborne Pathogens ◽

Electrochemical Impedance ◽

Limit Of Detection ◽

Foodborne Pathogen ◽

High Sensitivity ◽

Primary Objective ◽

Field Application ◽

Impedance Sensing ◽

Sensing Platform

A great improvement in food safety and quality controls worldwide has been achieved through the development of biosensing platforms. Foodborne pathogens continue to cause serious outbreaks, due to the ingestion of contaminated food. The development of new, sensitive, portable, high-throughput, and automated platforms is a primary objective to allow detection of pathogens and their toxins in foods. Listeria monocytogenes is one common foodborne pathogen. Major outbreaks of listeriosis have been caused by a variety of foods, including milk, soft cheeses, meat, fermented sausages, poultry, seafood and vegetable products. Due to its high sensitivity and easy setup, electrochemical impedance spectroscopy (EIS) has been extensively applied for biosensor fabrication and in particular in the field of microbiology as a mean to detect and quantify foodborne bacteria. Here we describe a miniaturized, portable EIS platform consisting of a microfluidic device with EIS sensors for the detection of L. monocytogenes in milk samples, connected to a portable impedance analyzer for on-field application in clinical and food diagnostics, but also for biosecurity purposes. To achieve this goal microelectrodes were functionalized with antibodies specific for L. monocytogenes. The binding and detection of L. monocytogenes was achieved in the range 2.2 × 103 cfu/mL to 1 × 102 with a Limit of Detection (LoD) of 5.5 cfu/mL.

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An electrochemical DNA biosensor for trace amounts of mercury ion quantification

Journal of Water and Health ◽

10.2166/wh.2016.293 ◽

2016 ◽

Vol 14 (5) ◽

pp. 808-815 ◽

Cited By ~ 5

Author(s):

Ferdaous Maâtouk ◽

Mouna Maâtouk ◽

Karima Bekir ◽

Houcine Barhoumi ◽

Abderrazak Maaref ◽

...

Keyword(s):

Electrochemical Impedance ◽

Specific Interaction ◽

High Sensitivity ◽

Differential Pulse ◽

Mercury Ion ◽

Dna Biosensor ◽

Electrochemical Dna Biosensor ◽

Dna Oligonucleotides ◽

Wastewater Samples ◽

Eis Measurements

In this work we report the development of an electrochemical DNA biosensor with high sensitivity for mercury ion detection. A new matrix based on gold nanoparticles (AuNPs)-glutathione (GSH)/cysteine was investigated. The interaction between DNA oligonucleotides and Hg2+ ions followed by the formation of Thymine–Hg2+–Thymine (T–Hg2+–T) structures was quantified using different electrochemical methods. It has been shown that the electrochemical impedance spectroscopy (EIS) measurements and the differential pulse voltammetry (DPV) confirmed the specific interaction between the oligonucleotide receptor layer and the Hg2+ ions. Besides, the developed sensor exhibited high sensitivity towards mercury among some examined metal ions such as Pb2+, Cu2+ and Cd2+. As a result, a high electrochemical response and low detection limit of 50 pM were estimated in the case of Hg2+ ions. The developed DNA biosensor was applied successfully to the determination of Hg2+ions in wastewater samples.

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