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

• Published in: Talanta (Oxford) 2024-02, Vol.268, p.125279-125279, Article 125279
• Main Authors: Baradoke, Ausra, Jarusaitis, Ainis, Reinikovaite, Viktorija, Jafarov, Ali, Elsakova, Alexandra, Franckevicius, Marius, Skapas, Martynas, Slibinskas, Rimantas, Drobysh, Maryia, Liustrovaite, Viktorija, Ramanavicius, Arunas
• Format: Article
• Language: English
• Subjects: Chronoamperometry; COVID-19; Cyclic voltammetry; Electrochemistry; Gold nanoparticles (AuNPs); Green synthesis; SARS-CoV-2
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2023.125279

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. Immobilized rS protein based biological recognition part enabled selective recognition of anti-rS antibodies. The current flux of AuNPs reduction (at +200 mV) in a pure phosphate buffer (PB) was employed as the transduction signal. It has been reported that the formation of anti-rS layers on the surface of AuNPs delays the electrode response time (ts), tracked at the current flux density values of 80 μA cm−2. Using the AuNP-modified SPE, we demonstrated a rapid anti-rS detection within a detection limit of 2 ng mL−1 (0.125 binding antibody units mL−1, 17 pM). This system can be applied to track the response of immune system towards SARS-CoV-2 infection and monitoring of Coronavirus Disease 2019 (COVID-19). [Display omitted] •Electrochemical systems for the determination of antibodies against the SARS-CoV-2 Spike protein (anti-rS) is reported.•Electrochemical system is based on screen-printed carbon electrodes (SPE).•SPE electrodes are modified by gold nanoparticles (AuNPs) formed using environmentally-friendly synthesis.•Biological recognition part of the system is based on immobilized recombinant SARS-CoV-2 virus protein.•The system is suitable for monitoring immune system responses towards SARS-CoV-2 virus infection.