Ultra-Fast and Sensitive Screening for Antibodies against the SARS-CoV-2 S1 Spike Antigen with a Portable Bioelectric Biosensor

Abstract

As a consequence of the progress of the global vaccination against the COVID-19 disease, fast, accurate and affordable assays are needed for monitoring the efficiency of developing immunity against the coronavirus at the population level. In this context, we herewith report the proof-of-concept development of an innovative bioelectric biosensor for the ultra-detection (in less than three minutes) of IgG antibodies against the SARS-CoV-2 S1 spike antigen. The biosensor comprises a disposable set of screen-printed electrodes upon which are immobilized cells engineered to bear the S1 protein on their surface. When anti-S1 antibodies are presented to the engineered cell population, a rapid, specific, and selective change of the cell membrane potential occurs; this is in turn recorded by a bespoke portable potentiometer. End results are communicated via Bluetooth to a smartphone equipped with a customized user interface. By using the novel biosensor, anti-S1 antibodies could be detected at concentrations as low as 5 ng/mL. In a preliminary clinical trial, positive results were derived from patients vaccinated or previously infected by the virus. Selectivity over other respiratory viruses was demonstrated by the lack of cross-reactivity to antibodies against rhinovirus. After further clinical validation and extension to also screen IgM, IgA and possible neutralizing antibodies, our approach is intended to facilitate the mass and reliable detection of antibodies in the early stages following vaccination and to monitor the duration and level of acquired immunity both in a clinical and self-testing environment.

Smartphone-based point-of-care testing of the SARS-CoV-2: A systematic review

“… Electro-chemical Nasopharyngeal swabs Sample dilution and incubation for 2 h. the peptidase of ACE2 domain 5.14 ng/mL for S1 and 2.09 ng/mL for S2 99.37% 1 NR Mobile application. [15] Electrochemical Nasopharyngeal swab NR a SARS-CoV-2 S protein 1 pF up to 3 µF NR <2 Android smartphone Mobile application readout the results remotely [7] Electrochemical Blood Exposure for piranha solution for 1 h at 100°C SARS-CoV-2 antibody ∼0.3 pM 99.2% NR NR Imaging processing [16] Electrochemical Blood centrifugation storage at −80°C till analysis SARS-CoV-2 S1 spike antigen 1 fg/mL 92.8% <3 Not Reported Result readout by a mobile application [17] electrochemical saliva RNA extraction and nucleic acid isolation thermally Viral antigen Not Reported 100% 60 Not Reported Mobile application [18] electrochemical blood Catalyzation to amplifies immune reaction. antigen of SARS-CoV-2 0.1 ng/mL, Not Reported 16 Not Reported Imaging [19] electrochemical saliva Dilution Incubation at room temperature for 30 min Streptavidin protein 64 nM = 5.12 pmole Not Reported <10 The device can be connected to Android and IOS systems Mobile application.…”

“…In another study, Mavrikou et al. [17] presented a proof-of-concept creation of a novel bioelectric biosensor to rapidly detect of IgG antibodies against the spike (S) protein antigen of SARS-COV-2 that utilizes immobilized Vero cells that express the corresponding antigen (HBsAg). The biosensor consists of a one-use collection of screen-printed electrodes that have been designed to be immobilized and express the S1 protein.…”

System for classifying antibody concentration against severe acute respiratory syndrome coronavirus 2 S1 spike antigen with automatic quick response generation for integration with health passports

“…QR codes have emerged as a valuable tool in this regard, providing several benefits during the pandemic such as contact tracing, vaccine passports, telemedicine, etc. [15,16]. Furthermore, QR codebased health information can be easily integrated into existing systems and technologies, making it accessible to a wide range of users, including those who may not have a strong technical background.…”