Rapid detection of SARS-CoV-2 antibodies using electrochemical impedance-based detector

Abstract

Coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was classified as a pandemic by the World Health Organization and has caused over 550,000 deaths worldwide as of July 2020. Accurate and scalable point-of-care devices would increase screening, diagnosis, and monitoring of COVID-19 patients. Here, we demonstrate rapid label-free electrochemical detection of SARS-CoV-2 antibodies using a commercially available impedance sensing platform. A 16-well plate containing sensing electrodes was pre-coated with receptor binding domain (RBD) of SARS-CoV-2 spike protein, and subsequently tested with samples of anti-SARS-CoV-2 monoclonal antibody CR3022 (0.1 g/ml, 1.0 g/ml, 10 g/ml). Subsequent blinded testing was performed on six serum specimens taken from COVID-19 and non-COVID-19 patients (1:100 dilution factor). The platform was able to differentiate spikes in impedance measurements from a negative control (1% milk solution) for all CR3022 samples. Further, successful differentiation and detection of all positive clinical samples from negative control was achieved. Measured impedance values were consistent when compared to standard ELISA test results showing a strong correlation between them (R ). Detection occurs in less than five minutes and the well-based platform provides a simplified and familiar testing interface that can be readily adaptable for use in clinical settings.

Electrochemical Biosensors for the Detection of SARS-CoV-2 and Other Viruses

“…Although they may present future use as point-of-care diagnostics, further work still needs to be done in order to miniaturize and lower the cost of these biosensors. Currently, optical, electrochemical, and molecularly imprinted biosensors are being designed for the detection of COVID-19 [143][144][145][146][147][148][149], as seen in Table 1:…”

Trends in biosensing platforms for SARS-CoV-2 detection: A critical appraisal against standard detection tools

“…The scheme representing the concept of SPCE/NPs/nano-Dendroids/GO/Ab probe fabrication to diagnose COVID-19 has been shown in Figure 4 B [ 100 ]. The label free electrochemical impedimetric sensor was prepared by Rashed et al to rapidly detect SARS-CoV-2 antibodies [ 101 ]. The sensor showed 100% accurate performance when results displayed by this sensor for clinical samples of COVID-19 negative and COVID-19 positive persons were compared with ELISA method.…”

“… Biosensor Pathogen Detection target Limit of detection Linear range Ref. EC SARS-CoV-2 S or N protein 19 ng/mL and 8 ng/mL - [ 103 ] EC SARS-CoV-2 Antibodies - - [ 101 ] EC SARS-CoV-2 N-gene 6.9 copies/μL 585.4 to 5.854 × 10 7 copies/μL [ 99 ] Cell-based SARS-CoV-2 Antigen 1 fgmL 1- 10 fg and 1 μg mL 1- [ 105 ] Optofluidic SARS-CoV-2 Antibody 0.5 pM 1- [ 83 ] Nanoplasmonic SARS-CoV-2 Virus particles 370 vp/mL 0 to 10 7 vp/mL [ 80 ] SPR SARS-CoV-2 Antibody 1.02 pM 2-1000 pM [ 82 ] LSPR SARS-CoV-2 RNA 1 pM 1 nM to 1 μM [ 106 ] Lateral flow optical/chemiluminescence SARS-CoV-2 Serum IgA - - [ 78 ] SERS-LFIA SARS-CoV-2 Antibody 1.28×10 7 -fold dilution - [ 79 ] Lateral flow SARS-CoV-2 RNA 12 copies...…”

Nanomaterials to tackle the COVID-19 pandemic

“…Finally, the results obtained from impedance measurements were compared to ELISA results of the same serum samples, and it was reported that there was a strong correlation between them. The limit of this biosensing method's detection was not reported because of two reasons, hardware noise and sample handling variations [ 59 ].…”