posted on 2021-07-19, 14:33authored byMaha Alafeef, Parikshit Moitra, Ketan Dighe, Dipanjan Pan
Efficient
monitoring of SARS-CoV-2 outbreak requires the use of
a sensitive and rapid diagnostic test. Although SARS-CoV-2 RNA can
be detected by RT-qPCR, the molecular-level quantification of the
viral load is still challenging, time-consuming, and labor-intensive.
Here, we report an ultrasensitive hyperspectral sensor (HyperSENSE)
based on hafnium nanoparticles (HfNPs) for specific detection of COVID-19
causative virus, SARS-CoV-2. Density functional theoretical calculations
reveal that HfNPs exhibit higher changes in their absorption wavelength
and light scattering when bound to their target SARS-CoV-2 RNA sequence
relative to the gold nanoparticles. The assay has a turnaround time
of a few seconds and has a limit of detection in the yoctomolar range,
which is 1 000 000-fold times higher than the currently
available COVID-19 tests. We demonstrated in ∼100 COVID-19
clinical samples that the assay is highly sensitive and has a specificity
of 100%. We also show that HyperSENSE can rapidly detect other viruses
such as influenza A H1N1. The outstanding sensitivity indicates the
potential of the current biosensor in detecting the prevailing presymptomatic
and asymptomatic COVID-19 cases. Thus, integrating hyperspectral imaging
with nanomaterials establishes a diagnostic platform for ultrasensitive
detection of COVID-19 that can potentially be applied to any emerging
infectious pathogen.