Multiplex quantitative detection of SARS-CoV-2 specific IgG and IgM antibodies based on DNA-assisted nanopore sensing

Abstract

The coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread into a global pandemic. Early and accurate diagnosis and quarantine remain the most effective mitigation strategy. Although reverse transcriptase polymerase chain reaction (RT-qPCR) is the gold standard for COVID-19 diagnosis, recent studies suggest that nucleic acids were undetectable in a significant number of cases with clinical features of COVID-19. Serologic assays that detect human antibodies to SARS-CoV-2 serve as a complementary method to diagnose these cases, as well as to identify asymptomatic cases and qualified convalescent serum donors. However, commercially available enzyme-linked immunosorbent assays (ELISA) are laborious and non-quantitative, while point-of-care assays suffer from low detection accuracy. To provide a serologic assay with high performance and portability for potential point-of-care applications, we developed DNA-assisted nanopore sensing for quantification of SARS-CoV-2 related antibodies in human serum. Different DNA structures were used as detection reporters for multiplex quantification of immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies against the nucleocapsid protein of SARS-CoV-2 in serum specimens from patients with conformed or suspected infection. Comparing to a clinically used point-of-care assay and an ELISA assay, our technology can reliably quantify SARS-CoV-2 antibodies with higher accuracy, large dynamic range, and potential for assay automation.

Rapid and quantitative detection of SARS-CoV-2 IgG antibody in serum using optofluidic point-of-care testing fluorescence biosensor

“…Several studies showed that the IgG concentration ranged between 1.4 and 4200 μg/mL in COVID-19 patients' serum, and the neutralization antibodies concentration should be higher than 1.0 μg/mL to ensure the effective protection [ [27] , [28] , [29] , [30] ]. Therefore, the sensitivity of the OPOCT is adequate for detecting S-IgG in COVID-19 patients’ serum, and was also comparable to those of other immunoassays [ 12 , 20 , 27 , [31] , [32] , [33] , [34] , [35] ] ( Table S1 ). Compared with the reported works, our method can achieve quantitative detection of IgG with high sensitivity (LOD = 12.5 ng/mL) and relatively short assay time (about 25 min).…”

SPEEDS: A portable serological testing platform for rapid electrochemical detection of SARS-CoV-2 antibodies

“…Targeting rapid and sensitive COVID-19 serology testing at the point of care (POC), a variety of portable immunosensing platforms have been developed based on microfluidics and biosensor technologies ( Fabiani et al, 2021 ; Kim et al, 2021a ; Lee et al, 2021 ; Li et al, 2021 ; Raziq et al, 2021 ; Roda et al, 2021 ; Tan et al, 2020a ; Torrente-Rodríguez et al, 2020 ; Yakoh et al, 2021 ; Zakashansky et al, 2021 ; C. Zhang et al, 2021 ; Z. Zhang et al, 2021 ; Zhao et al, 2021 ).…”

A Rolling Circle-Amplified G-Quadruplex/Hemin DNAzyme for Chemiluminescence Immunoassay of the SARS-CoV-2 Protein

“… 7 Although RT-PCR is a current standard method for SARS-CoV-2 diagnosis due to its high precision and specificity, 8 , 9 some data indicate that this detection technique is not suitable for all cases with clinical features of SARS-CoV-2, and serologic assay has become an indispensable tool as a complementary method for accurate diagnosis. 10 In serologic assay, commercially available ELISA is considered as a reliable detection method, but its efficiency is limited by laborious and time-consuming operation. Although a GICA-based method is convenient and time-saving for SARS-CoV-2 detection, its low detection sensitivity is not satisfactory for early and prompt screening of this disease.…”