Electrochemical sensing platform based on covalent immobilization of thionine onto gold electrode surface via diazotization-coupling reaction

This paper describes for the first time an electrochemical biosensor, which employs a DNA probe modified with a redox tag close to electrode surface, for picomolar detection of a sequence-specific DNA-binding protein.

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Detection of SARS-CoV-2 Viral Particles Using Direct, Reagent-Free Electrochemical Sensing

10.26434/chemrxiv.13083479 ◽

2020 ◽

Author(s):

Hanie Yousefi ◽

alam mahmud ◽

Dingran Chang ◽

Jagotamoy Das ◽

Surath Gomis ◽

...

Keyword(s):

Electrode Surface ◽

Gold Electrode ◽

Direct Analysis ◽

Electrochemical Sensing ◽

New Method ◽

Spike Protein ◽

Positive Potential ◽

Molecular Sensor ◽

Viral Particles ◽

Kinetics Of

This manuscript describes a new method that enables direct analysis of viral particles in unprocessed samples.Using an electrochemical readout method that requires no external reagents, we detect the SARS-CoV-2 virus in the saliva of infected patients.The approach relies on a molecular sensor tethered to the surface of a gold electrode that contains an antibody, specific to the targetof interest, which here is the SARS-CoV-2 S1 spike protein that is displayed on the viral capsule. The antibody is attached to the electrode using a negatively charged linker that is composed of DNA. When a positive potential is applied to the electrode, the sensor complex is attracted to the electrode surface. The kinetics of transport is measured using chronoamperometry and readout is possible based on the absense or precense of virus and its effect on the complex movevment on electrode surface.

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Detection of SARS-CoV-2 Viral Particles Using Direct, Reagent-Free Electrochemical Sensing

10.26434/chemrxiv.13083479.v1 ◽

2020 ◽

Author(s):

Hanie Yousefi ◽

alam mahmud ◽

Dingran Chang ◽

Jagotamoy Das ◽

Surath Gomis ◽

...

Keyword(s):

Electrode Surface ◽

Gold Electrode ◽

Direct Analysis ◽

Electrochemical Sensing ◽

New Method ◽

Spike Protein ◽

Positive Potential ◽

Molecular Sensor ◽

Viral Particles ◽

Kinetics Of

This manuscript describes a new method that enables direct analysis of viral particles in unprocessed samples.Using an electrochemical readout method that requires no external reagents, we detect the SARS-CoV-2 virus in the saliva of infected patients.The approach relies on a molecular sensor tethered to the surface of a gold electrode that contains an antibody, specific to the targetof interest, which here is the SARS-CoV-2 S1 spike protein that is displayed on the viral capsule. The antibody is attached to the electrode using a negatively charged linker that is composed of DNA. When a positive potential is applied to the electrode, the sensor complex is attracted to the electrode surface. The kinetics of transport is measured using chronoamperometry and readout is possible based on the absense or precense of virus and its effect on the complex movevment on electrode surface.

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Detection of SARS-CoV-2 Viral Particles using Direct, Reagent-Free Electrochemical Sensing

10.26434/chemrxiv.13103561 ◽

2020 ◽

Author(s):

Hanie Yousefi ◽

alam mahmud ◽

Dingran Chang ◽

Jagotamoy Das ◽

Surath Gomis ◽

...

Keyword(s):

Electrode Surface ◽

Gold Electrode ◽

Direct Analysis ◽

Electrochemical Sensing ◽

New Method ◽

Spike Protein ◽

Positive Potential ◽

Molecular Sensor ◽

Viral Particles ◽

Kinetics Of

This manuscript describes a new method that enables direct analysis of viral particles in unprocessed samples.Using an electrochemical readout method that requires no external reagents, we detect the SARS-CoV-2 virus in the saliva of infected patients.The approach relies on a molecular sensor tethered to the surface of a gold electrode that contains an antibody, specific to the targetof interest, which here is the SARS-CoV-2 S1 spike protein that is displayed on the viral capsule. The antibody is attached to the electrode using a negatively charged linker that is composed of DNA. When a positive potential is applied to the electrode, the sensor complex is attracted to the electrode surface. The kinetics of transport is measured using chronoamperometry and readout is possible based on the absense or precense of virus and its effect on the complex movevment on electrode surface.

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Detection of SARS-CoV-2 Viral Particles using Direct, Reagent-Free Electrochemical Sensing

10.26434/chemrxiv.13103561.v1 ◽

2020 ◽

Author(s):

Hanie Yousefi ◽

alam mahmud ◽

Dingran Chang ◽

Jagotamoy Das ◽

Surath Gomis ◽

...

Keyword(s):

Electrode Surface ◽

Gold Electrode ◽

Direct Analysis ◽

Electrochemical Sensing ◽

New Method ◽

Spike Protein ◽

Positive Potential ◽

Molecular Sensor ◽

Viral Particles ◽

Kinetics Of

This manuscript describes a new method that enables direct analysis of viral particles in unprocessed samples.Using an electrochemical readout method that requires no external reagents, we detect the SARS-CoV-2 virus in the saliva of infected patients.The approach relies on a molecular sensor tethered to the surface of a gold electrode that contains an antibody, specific to the targetof interest, which here is the SARS-CoV-2 S1 spike protein that is displayed on the viral capsule. The antibody is attached to the electrode using a negatively charged linker that is composed of DNA. When a positive potential is applied to the electrode, the sensor complex is attracted to the electrode surface. The kinetics of transport is measured using chronoamperometry and readout is possible based on the absense or precense of virus and its effect on the complex movevment on electrode surface.

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Redox-active Monolayers Deposited on Gold Electrode Surface–Universal Platforms for Electrochemical Sensing

Sensors and Materials ◽

10.18494/sam.2020.2662 ◽

2020 ◽

Vol 32 (3) ◽

pp. 1065

Author(s):

Jerzy Radecki ◽

Hanna Radecka

Keyword(s):

Electrode Surface ◽

Gold Electrode ◽

Electrochemical Sensing ◽

Redox Active

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Paper-Based Competitive Immunochromatography Coupled with an Enzyme-Modified Electrode to Enable the Wireless Monitoring and Electrochemical Sensing of Cotinine in Urine

Sensors ◽

10.3390/s21051659 ◽

2021 ◽

Vol 21 (5) ◽

pp. 1659

Author(s):

Nutcha Larpant ◽

Pramod K. Kalambate ◽

Tautgirdas Ruzgas ◽

Wanida Laiwattanapaisal

Keyword(s):

Glucose Oxidase ◽

Modified Electrode ◽

Near Field ◽

Electrochemical Measurement ◽

Electrochemical Sensing ◽

Urine Samples ◽

Lateral Flow Strip ◽

Wireless Monitoring ◽

Sensing Platform ◽

Combined Strategy

This paper proposes a combined strategy of using paper-based competitive immunochromatography and a near field communication (NFC) tag for wireless cotinine determination. The glucose oxidase labeled cotinine antibody specifically binds free cotinine in a sample, whereas the unoccupied antibody attached to BSA-cotinine at the test line on a lateral flow strip. The glucose oxidase on the strip and an assistant pad in the presence of glucose generated H2O2 and imposed the Ag oxidation on the modified electrode. This enabled monitoring of immunoreaction by either electrochemical measurement or wireless detection. Wireless sensing was realized for cotinine in the range of 100–1000 ng/mL (R2 = 0.96) in PBS medium. Undiluted urine samples from non-smokers exhibited an Ag-oxidation rate three times higher than the smoker’s urine samples. For 1:8 diluted urine samples (smokers), the proposed paper-based competitive immunochromatography coupled with an enzyme-modified electrode differentiated positive and negative samples and exhibited cotinine discrimination at levels higher than 12 ng/mL. This novel sensing platform can potentially be combined with a smartphone as a reader unit.

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