Back to Search Start Over

Analysis of the optical response of a SARS-CoV-2-directed colorimetric immunosensor

Authors :
Emanuela Scardapane
Antonio Minopoli
Bartolomeo Della Ventura
Raffaele Campanile
Raffaele Velotta
Adriano Acunzo
Minopoli, Antonio
Scardapane, Emanuela
Acunzo, Adriano
Campanile, Raffaele
Della Ventura, Bartolomeo
Velotta, Raffaele
Source :
AIP Advances, Vol 11, Iss 6, Pp 065319-065319-7 (2021)
Publication Year :
2021
Publisher :
AIP Publishing LLC, 2021.

Abstract

The optical response of different configurations of functionalized gold nanoparticles (f-AuNPs) and SARS-CoV-2 virions is simulated in order to explore the behavior of a colloidal solution containing 105–1013 virions/ml. The analysis herein reported is carried out for three concentration regimes: (i) low (≲108 virions/ml), (ii) intermediate (∼109–1010 virions/ml), and (iii) high (≳1011 virions/ml). Given the high binding effectiveness of f-AuNPs to virions, three different configurations are expected to arise: (i) virions completely surrounded by f-AuNPs, (ii) aggregates (dimers or trimers) of virions linked by f-AuNPs, and (iii) single f-AuNP surrounded by virions. It is demonstrated that 20 nm diameter gold nanoparticles functionalized against all three kinds of SARS-CoV-2 proteins (membrane, envelope, and spike) allow one to reach a limit of detection (LOD) of ∼106 virions/ml, whereas the use of only one kind of f-AuNP entails a ten-fold worsening of the LOD. It is also shown that the close proximity (∼5 nm) of the f-AuNP to the virions assumed throughout this analysis is essential to avoid the hook effect, thereby pointing out the importance of realizing an apt functionalization procedure that keeps thin the dielectric layer (e.g., proteins or aptamers) surrounding the gold nanoparticles.

Details

Language :
English
ISSN :
21583226
Volume :
11
Issue :
6
Database :
OpenAIRE
Journal :
AIP Advances
Accession number :
edsair.doi.dedup.....9104d3bb29affc14a627b1987ea0537d