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

• Published in: Microchemical journal Vol. 168; p. 106445
• Main Author: Liv, Lokman
• Format: Journal Article
• Language: English
• Published: United States Elsevier B.V 01.09.2021
• Subjects: COVID-19; Gold-cluster; Immunosensor; SARS-CoV-2; Square wave voltammetry; COVID-19; Gold-cluster; SARS-CoV-2; Square wave voltammetry; Immunosensor
• ISSN: 0026-265X; 1095-9149
• DOI: 10.1016/j.microc.2021.106445

[Display omitted] •The developed sensor is ultra-sensitive and has short preparation time.•The developed sensor could reduce the false-negative ratio.•No cross-reactivity with MERS-CoV.•Simple and rapid analysis of saliva and oropharyngeal swab samples.•Possibility of fabricating ready-to-use sensor and kit. 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 0.9 V was used to detect the SARS-CoV-2 spike antibody. When saliva and oropharyngeal swab samples were analysed, the recovery and relative standard deviation values were 96.97%–101.99% and 4.99%–5.74%, respectively. The method’s limit of detection relative to the SARS-CoV-2 spike antibody in synthetic media and in saliva or oropharyngeal swab samples was 0.01 ag/mL, while the immunosensor’s linear response to the SARS-CoV-2 spike antibody varied from 0.1 to 1000 ag/mL. The cross-reactivity of the Middle East respiratory syndrome-coronavirus spike antigen was evaluated after being immobilised onto the functionalised gold-cluster based sensor, indicated that the good specifity of the produced immunosensor.