Abstract
Background: As several vaccines for SARS-CoV-2 have been developed, a large proportion of individuals have been vaccinated worldwide so far. The rapid and accurate immunoassays are urgently needed for detecting the specific virus-neutralizing antibody (NAb), which reflect the protective effect of the vaccines among different populations.
Methods: In this study, we designed a quantum dot lateral flow immunoassay strip (QD-LFIA) for smartphones for the detection of specific IgG or neutralizing antibodies in SARS-CoV-2 in human serum or whole blood samples. The recombinant receptor binding domain of the SARS-CoV-2 spike protein was used as the antigen to combine with NAb or angiotensin-converting enzyme 2.
Results: Among 81 patients who recovered from COVID-19 who were diagnosed using the nucleic acid test initially, 98.8% (80/81) were positive for IgG and 88.9% (72/81) were positive for NAb by QD-LFIA. Among 64 individuals inoculated with inactivated vaccines and six subunit vaccines, 90% (63/70) were positive for IgG and 82.9% (58/70) were positive for NAb by QD-LFIA, whereas no cross-reaction was found in 150 healthy blood donors, two patients with influenza B, and three patients with common cold.
Conclusion: The established platform could achieve a rapid and accurate detection of NAb specific to SARS-CoV-2, which could be used for detecting the protective effect of the vaccines in areas of world that currently affected by the pandemic.
Keywords: IgG; Neutralizing antibody; Quantum dot; SARS-CoV-2; Smartphone.
【저자키워드】 neutralizing antibody, SARS-CoV-2, IgG, Smartphone, Quantum dot, 【초록키워드】 COVID-19, neutralizing antibody, Vaccine, pandemic, Inactivated Vaccines, Neutralizing antibodies, Influenza, angiotensin-converting enzyme 2, Spike protein, Receptor binding domain, Antigen, immunoassay, lateral flow immunoassay, nucleic acid, Blood donors, Whole blood, Inactivated vaccine, nucleic acid test, SARS-CoV-2 spike protein, Patient, Smartphone, common cold, influenza B, platform, human serum, cross-reaction, Quantum dot, protective effect, Angiotensin-converting enzyme, angiotensin, subunit vaccines, the vaccines, reaction, individual, two patients, positive, healthy blood donors, populations, virus-neutralizing antibody, quantum, affected, was used, proportion, inoculated, diagnosed, the vaccine, patients with influenza, the SARS-CoV-2, 【제목키워드】 lateral flow immunoassay, anti-SARS-CoV-2 IgG, development,