Photoluminescence-based biosensor for the detection of antibodies against SARS-CoV-2 virus proteins by ZnO tetrapod structure integrated within microfluidic system.

This paper reports on development of an optical biosensor for the detection of antibodies against SARS-CoV-2 virus proteins in blood serum. ZnO nanotetrapods with high surface area and stable room temperature photoluminescence (PL) were selected as transducers. Structure and optical properties of the ZnO tetrapods have been studied by XRD, SEM and Raman spectroscopy.

Molecularly imprinted composite-based biosensor for the determination of SARS-CoV-2 nucleocapsid protein.

This article aims to present a comparative study of three polypyrrole-based molecularly imprinted polymer (MIP) systems for the detection of the recombinant severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleocapsid protein (rN). The rN is known for its relatively low propensity to mutate compared to other SARS-CoV-2 antigens. The aforementioned systems include screen-printed carbon electrodes (SPCE) modified with gold nanostructures (MIP1), platinum nanostructures (MIP2), and the unmodified SPCE (MIP3), which was used for control.

Electrochemical biosensing based comparative study of monoclonal antibodies against SARS-CoV-2 nucleocapsid protein.

In this study, we are reporting an electrochemical biosensor for the determination of three different clones of monoclonal antibodies (mAbs) against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) recombinant nucleocapsid protein (rN). The nucleocapsid protein was chosen as a system component identifying and discriminating antibodies that occur after virus infection instead of S protein used in serological tests to measure antibodies raised after vaccination and infection. The sensing platform was based on a screen-printed carbon electrode (SPCE) covered with gold nanoparticles (AuNP) and subsequently modified with a self-assembled monolayer (SAM) to ensure the covalent immobilization of the rN.

Detection of antibodies against SARS-CoV-2 Spike protein by screen-printed carbon electrodes modified by colloidal gold nanoparticles.

In this work, electrochemical bioanalytical systems for the determination of antibodies against the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Spike protein (anti-rS) is reported. Environmentally friendly chemicals were applied in the synthesis of gold nanoparticles (AuNPs). The AuNPs were integrated onto the screen-printed carbon electrodes (SPE), and the biological recognition part was based on recombinant SARS-CoV-2 Spike protein (rS), which during the immobilization was cross-linked by glutaraldehyde.

Electrochemical capacitance spectroscopy based determination of antibodies against SARS-CoV-2 virus spike protein.

In this study, we are reporting a novel electrochemical capacitance spectroscopy (ECS) platform designed for the sensitive and label-free detection of antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus spike protein (anti-rS) in diluted blood serum. The determination of anti-rS is crucial for identification individuals who have been infected by SARS-CoV-2 virus and may have acquired immunity. The rS protein was immobilized on a screen-printed carbon electrode, which was incubated in diluted blood serum containing anti-rS antibodies.

Polyaniline-based electrochemical immunosensor for the determination of antibodies against SARS-CoV-2 spike protein.

In this work, we report an impedimetric system for the detection of antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Spike protein. The sensing platform is based on recombinant Spike protein (SCoV2-rS) immobilized on the phytic acid doped polyaniline films (PANI-PA). The affinity interaction between immobilized SCoV2-rS protein and antibodies in the physiological range of concentrations was registered by electrochemical impedance spectroscopy.

Determination of rSpike Protein by Specific Antibodies with Screen-Printed Carbon Electrode Modified by Electrodeposited Gold Nanostructures.

In this research, we assessed the applicability of electrochemical sensing techniques for detecting specific antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike proteins in the blood serum of patient samples following coronavirus disease 2019 (COVID-19). Herein, screen-printed carbon electrodes (SPCE) with electrodeposited gold nanostructures (AuNS) were modified with L-Cysteine for further covalent immobilization of recombinant SARS-CoV-2 spike proteins (rSpike). The affinity interactions of the rSpike protein with specific antibodies against this protein (anti-rSpike) were assessed using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods.

Electrochemical Determination of Interaction between SARS-CoV-2 Spike Protein and Specific Antibodies.

The serologic diagnosis of coronavirus disease 2019 (COVID-19) and the evaluation of vaccination effectiveness are identified by the presence of antibodies specific to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this paper, we present the electrochemical-based biosensing technique for the detection of antibodies specific to the SARS-CoV-2 proteins. Recombinant SARS-CoV-2 spike proteins (rSpike) were immobilised on the surface of a gold electrode modified by a self-assembled monolayer (SAM).

Biosensors for the Determination of SARS-CoV-2 Virus and Diagnosis of COVID-19 Infection.

Monitoring and tracking infection is required in order to reduce the spread of the coronavirus disease 2019 (COVID-19), induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To achieve this goal, the development and deployment of quick, accurate, and sensitive diagnostic methods are necessary. The determination of the SARS-CoV-2 virus is performed by biosensing devices, which vary according to detection methods and the biomarkers which are inducing/providing an analytical signal.

Affinity Sensors for the Diagnosis of COVID-19.

The coronavirus disease 2019 (COVID-19) outbreak caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was proclaimed a global pandemic in March 2020. Reducing the dissemination rate, in particular by tracking the infected people and their contacts, is the main instrument against infection spreading. Therefore, the creation and implementation of fast, reliable and responsive methods suitable for the diagnosis of COVID-19 are required.

Cytotoxic and antiproliferative effects of thymoquinone on rat C6 glioma cells depend on oxidative stress.

Thymoquinone (TQ) is a highly perspective chemotherapeutic agent against gliomas and glioblastomas because of its ability to cross the blood-brain barrier and its selective cytotoxicity for glioblastoma cells compared to primary astrocytes. Here, we tested the hypothesis that TQ-induced mild oxidative stress provokes C6 glioma cell apoptosis through redox-dependent alteration of MAPK proteins. We showed that low concentrations of TQ (20-50 μM) promoted cell-cycle arrest and induced hydrogen peroxide generation as a result of NADH-quinone oxidoreductase 1-catalyzed two-electron reduction of this quinone.