First DFT-supported point of care and novel electrochemical biosensing: Determination of yellow fever NS1 antibody in human plasma.

In our study, we developed a point of care electrochemical biosensing platform based on the functionalized cysteine-positioned gold electrode to diagnose yellow fever disease from human plasma samples. The developed platform underwent characterization through diverse methods encompassing cyclic voltammetry, electrochemical impedance spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, and density-functional theory. The capacitive interaction between yellow fever virus non-structural antigen and antibody gave a cathodic signal at approximately -260 mV, and increased in proportion to the amount of non-structural antibody.

A novel thienothiophene-based "dual-responsive" probe for rapid, selective and sensitive detection of hypochlorite.

Background: Hypochlorite/hypochlorous acid (ClO/HOCl) is a biologically crucial reactive oxygen species (ROS), produced in living organisms and has a critical role as an antimicrobial agent in the natural defense system. However, when ClO is produced excessively, it can lead to the oxidative damage of biomolecules, resulting in organ damage and various diseases. Therefore, it is imperative to have a straightforward, quick and reliable method for over watching the minimum amount of ClO in different environments.

Rigorous pH measurement in non-aqueous solution: measurement method and reference values in ethanol.

The recently introduced unified pH ([Formula: see text]) concept enables rigorous pH measurements in non-aqueous and mixed media while at the same time maintaining comparability to the conventional aqueous pH scale. However, its practical application is hindered by a shortage of reference [Formula: see text] values. In order to improve this situation, the European Metrology Research Project (EMPIR) UnipHied ("Realisation of a UnipHied pH scale") launched an interlaboratory comparison among highly experienced electrochemistry expert laboratories to assign the first such reference [Formula: see text] values by adopting an extensive statistical treatment of the reported measurement data: to phosphate buffer in water-ethanol mixture (50 wt% of ethanol) and ammonium formate buffer in pure ethanol.

Electrocatalytic Determination of Uric Acid with the Poly(Tartrazine)-Modified Pencil Graphite Electrode in Human Serum and Artificial Urine.

A novel electrocatalytic sensing strategy was built for uric acid (UA) determination with an exceptionally developed poly(tartrazine)-modified activated pencil graphite electrode (pTRT/aPGE) in human serum and artificial urine. The oxidation signal of UA at 275 mV in pH 7.5 phosphate buffer solution served as the analytical response.

Signal-Enhanced Electrochemical Determination of Quercetin with Poly(chromotrope fb)-Modified Pencil Graphite Electrode in Vegetables and Fruits.

A novel signal-enhanced electrochemical sensing strategy was constructed for quercetin determination with a peculiarly developed poly(chromotrope fb)-modified activated pencil graphite electrode in vegetables and fruits. The oxidation signal of quercetin at 118 mV in an alcoholic solution served as the analytical response. The produced platform, characterized by cyclic voltammetry, electrochemical impedance spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy, could detect 1.

Discriminative electrochemical biosensing of wildtype and omicron variant of SARS-CoV-2 nucleocapsid protein with single platform.

Electrochemical biosensors for determining wildtype and omicron variant of the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) nucleocapsid antigen in nasopharyngeal swab samples were produced by using functionalised graphene oxide and the wildtype and omicron types of SARS-CoV-2 nucleocapsid antibody modified glassy carbon electrodes. The developed biosensors characterised by cyclic voltammetry, scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy were able to detect 0.76 and 0.

Development and characterisation of cysteine-based gold electrodes for the electrochemical biosensing of the SARS-CoV-2 spike antigen.

This article describes three novel electrochemical biosensing platforms developed to determine the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) spike antigen protein: glutaraldehyde, SARS-CoV-2 spike antibody and bovine serum albumin; ,-dicyclohexyl carbodiimide/4-(dimethylamino)pyridine functionalised SARS-CoV-2 spike antibody and bovine serum albumin; and 1-ethyl-3-[3-dimethylaminopropyl]-carbodiimide hydrochloride/-hydroxysuccinimide functionalised SARS-CoV-2 spike antibody and bovine serum albumin modified cysteine-based gold-flower modified glassy carbon electrodes. Two of the produced biosensors having better signals were used to determine the SARS-CoV-2 spike antigen in spiked-saliva and clinical samples containing gargle and mouthwash liquids and characterised using cyclic voltammetry, scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. The study provides highly significant information in terms of how coupling reagents ought to be used with linkers consisting of both amine and carboxylic acid terminals ( cysteine).

An Electrochemical Biosensing Platform for the SARS-CoV-2 Spike Antibody Detection Based on the Functionalised SARS-CoV-2 Spike Antigen Modified Electrode.

We developed an electrochemical biosensing platform using gold-clusters, cysteamine, the spike protein of the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) antigen and bovine serum albumin on a glassy carbon electrode able to determine the SARS-CoV-2 spike antibody. The developed biosensor could detect 9.3 ag/mL of the SARS-CoV-2 spike antibody in synthetic media in 20 min in a linear range from 0.

Electrochemical biosensing platform based on hydrogen bonding for detection of the SARS-CoV-2 spike antibody.

Among the deadliest pandemics in history, coronavirus disease 2019 (COVID-19) has wreaked havoc on human lives, economies and public health systems worldwide. To temper its effects, diagnostic methods that are simple, rapid, inexpensive, accurate, selective and sensitive continue to be necessary. In our study, we developed an electrochemical biosensing platform based on gold clusters, mercaptoethanol, the spike protein of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) antigen and bovine serum albumin-modified glassy carbon electrode able to detect the SARS-CoV-2 spike antibody.

Colorimetric and electrochemical detection of SARS-CoV-2 spike antigen with a gold nanoparticle-based biosensor.

Since emerging in China in December 2019, COVID-19 has spread globally, wreaked havoc for public health and economies worldwide and, given the high infectivity and unexpectedly rapid spread of the virus responsible-that is, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-urged the World Health Organization to declare it a pandemic. In response, reducing the virus's adverse effects requires developing methods of early diagnosis that are reliable, are inexpensive and offer rapid response. As demonstrated in this article, the colorimetric and electrochemical detection of SARS-CoV-2 spike antigen with gold nanoparticle-based biosensors may be one such method.

Corrigendum to "Electrochemical immunosensor platform based on gold-clusters, cysteamine and glutaraldehyde modified electrode for diagnosing COVID-19" [Microchem. J. 168 (2021) 106445].

[This corrects the article DOI: 10.1016/j.microc.

Fluorescein Based Three-channel Probe for the Selective and Sensitive Detection of CO Ions in an Aqueous Environment and Real Water Samples.

We have constructed a novel fluorescein-based fluorescent chemosensor, FL-In, functionalised with an indole moiety and capable of sensing by both the optical "turn-on" and electrochemical detection of carbonate ions (CO) in aqueous media. The probe exhibits excellent selectivity and a low detection limit (0.27 µM) regarding carbonate ions by a possible coordination and hydrolysis reaction mechanism.

A rapid, ultrasensitive voltammetric biosensor for determining SARS-CoV-2 spike protein in real samples.

The ongoing coronavirus disease 2019 (COVID-19) pandemic continues to threaten public health systems all around the world. In controlling the viral outbreak, early diagnosis of COVID-19 is pivotal. This article describes a novel method of voltammetrically determining severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein with a newly designed sensor involving bovine serum albumin, SARS-CoV-2 spike antibody and a functionalised graphene oxide modified glassy carbon electrode (BSA/AB/f-GO/GCE) or screen-printed electrode (BSA/AB/f-GO/SPE).

Electrochemical immunosensor platform based on gold-clusters, cysteamine and glutaraldehyde modified electrode for diagnosing COVID-19.

Amid the global threat caused by the coronavirus disease 2019 (COVID-19) pandemic, developing sufficiently rapid, accurate, sensitive and selective methods of diagnosing both symptomatic and asymptomatic cases is essential to alleviating and controlling the pandemic's effects. This article describes an electrochemical immunoassay platform developed to determine the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) spike antibody by using gold-clusters capped with cysteamine, glutaraldehyde, the spike protein of the SARS-CoV-2 antigen and bovine serum albumin on a glassy carbon electrode. The electrochemical oxidation signal of the antigen-based immunosensor at 0.

A novel voltammetric method for the sensitive and selective determination of carbonate or bicarbonate ions by an azomethine-H probe.

Our study involved a simple, sensitive voltammetric method of determining either carbonate or bicarbonate ions independently with azomethine-H and a disposable pencil graphite electrode. The reduction of azomethine-H-carbonate complexes at approximately -930 mV formed in acetic acid-acetate buffer solution (pH: 4.25) was evaluated as a response.

Cost-effective voltammetric determination of boron in dried fruits and nuts using modified electrodes.

Cost effective, simple and accurate two voltammetric methods for determination of boron in hazelnut, peanut, almond, raisin, prune and date samples were described. Metal nanoparticles-carbon nanotube modified glassy carbon electrode (MNP/CNT/GCE, M = Au or Cu) and poly xylenol orange modified pencil graphite electrode (p-XO/PGE) were used as working electrodes. The oxidation of alizarin red s (ARS) in the boron-ARS complex at MNP/CNT/GCE and the oxidation of tiron in the B-tiron complex at p-XO/PGE were monitored as response.