Electrochemical lateral-flow device for rapid COVID-19 antigen-diagnostic testing

• Published in: Bioelectrochemistry (Amsterdam, Netherlands) Netherlands), 2023-08, Vol.152, p.108438-108438, Article 108438
• Main Authors: Deenin, Wanwisa, Yakoh, Abdulhadee, Pimpitak, Umaporn, Pasomsub, Ekawat, Rengpipat, Sirirat, Crespo, Gastón A., Chaiyo, Sudkate
• Format: Article
• Language: English
• Subjects: ACE2; Angiotensin-Converting Enzyme 2; Antigen test kits; COVID-19; COVID-19 - diagnosis; COVID-19 Testing; Electrochemical detection; Humans; Immunoassay - methods; Lateral -flow immunosensor; SARS-CoV-2; Sensitivity and Specificity
• ISSN: 1567-5394; 1878-562X; 1878-562X
• DOI: 10.1016/j.bioelechem.2023.108438

[Display omitted] •ATK combined with electrochemical biosensors for diagnosis of COVID-19.•Binding ACE2-immobilization region on the screen-printed electrode.•Detection of COVID-19 antigen was demonstrated using nasopharyngeal samples.•High sensitivity and specificity detection of SARS-CoV-2 using an E-test strip.•E-strip test is proposed as a new platform for future emerging diseases. Antigen test kits (ATK) are extensively utilized for screening and diagnosing COVID-19 because they are easy to operate. However, ATKs exhibit poor sensitivity and cannot detect low concentrations of SARS-CoV-2. Herein, we present a new, highly sensitive, and selective device obtained by combining the principle of ATKs with electrochemical detection for COVID-19 diagnosis, which can be quantitatively assessed using a smartphone. An electrochemical test strip (E-test strip) was constructed by attaching a screen-printed electrode inside a lateral-flow device to exploit the remarkable binding affinity of SARS-CoV-2 antigen to ACE2. The ferrocene carboxylic acid attached to SARS-CoV-2 antibody acts as an electroactive species when it binds to SARS-CoV-2 antigen in the sample before it flows continuously to the ACE2-immobilization region on the electrode. Electrochemical-assay signal intensity on smartphones increased proportionally to the concentration of SARS-CoV-2 antigen (LOD = 2.98 pg/mL, under 12 min). Additionally, the application of the single-step E-test strip for COVID-19 screening was demonstrated using nasopharyngeal samples, and the results were consistent with those obtained using the gold standard (RT-PCR). Therefore, the sensor demonstrated excellent performance in assessing and screening COVID-19, and it can be used professionally to accurately verify diagnostic data while remaining rapid, simple, and inexpensive.