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This content will become publicly available on October 1, 2026

Title: Nanoparticle-supported, rapid, digital quantification of neutralizing antibodies against SARS-CoV-2 variants
The measurement of neutralizing immune responses to viral infection is essential, given the heterogeneity of human immunity and the emergence of new virus strains. However, neutralizing antibody (nAb) assays often require high-level biosafety containment, sophisticated instrumentation, and long detection times. Here, as a proof-of-principle, we designed a nanoparticle-supported, rapid, electronic detection (NasRED) assay to assess the neutralizing potency of monoclonal antibodies (mAbs) against SARS-CoV-2. The gold nanoparticles (AuNPs) coated with human angiotensin-converting enzyme 2 (ACE2) protein as nAb potency reporters were mixed with the mAbs to be tested, as well as streptavidin-conjugated multivalent spike (S) protein or their receptor binding domains (RBD). High-affinity and ACE2-competitive nAbs alter the S (or RBD)-to-ACE2 binding level and modulate AuNP cluster formation and precipitation. The amount of free-floating AuNP reporters is quantified by a semiconductor-based readout system that measures the AuNPs' optical extinction, producing nAb signals that can differentiate SARS-CoV-2 variants (Wuhan-Hu-1, Gamma, and Omicron). The modular design nature, short assay time (less than 30 minutes), and portable and inexpensive readout system make this NasRED-nAb assay applicable to measuring vaccine potency, immune responses to infection, and the efficacy of antibody-based therapies.  more » « less
Award ID(s):
1847324
PAR ID:
10637930
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Biosensors and Bioelectronics
Date Published:
Journal Name:
Biosensors and Bioelectronics
Volume:
285
Issue:
C
ISSN:
0956-5663
Page Range / eLocation ID:
117549
Subject(s) / Keyword(s):
COVID-19 SARS-CoV-2 variants, Metal nanoparticles Rapid electronic detection Neutralizing assay
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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