The COVID-19 pandemic has proven that early and fast diagnosis is especially important for rapidly spreading and quickly changing viruses. Current sensing platforms need to address growing challenges in low number of targets, technological limitations (detection limit, linear dynamic range, stability, and reliability), as well as economical aspects that limit their implementation into resource-scarce settings.

I will present the latest bioinspired sensor technologies^1,2 we developed for detecting SARS-CoV-2 with high sensitivity and specificity that can provide reliable results in seconds to minutes and used with a wide array of specimens. The first platform is using peptides that mimic the ACE-2 protein. We have demonstrated that viral spike proteins binding to agonist peptides give rise to unique Raman spectra that can be enhanced to the single molecule regime using plasmonic nanostructures. The Raman signal generated from the selective target binding provides a positive readout, that can be read with a portable, handheld Raman spectrometer. The proposed assay is appropriate for use in clinics, transportation hubs, and other point-of-need screening locations. This sensor technology will provide a multivariate input for machine learning algorithms that enable rapid assay for screening of the SARS-CoV-2 virus and easily adaptable for emerging viruses.
The second platform mimics a different aspect of the virus-cell interaction and leverages the unique binding of viruses to the cell surface-anchored glycocalyx. By anchoring sugar polymers to a paper-based strip, we were able to uniquely capture SARS-COV-2. This sensor we term, GlycoGrip can selectively, sensitively, and rapidly detect SARS-CoV-2 and its variants in biofluids. Employing the power of the glycocalyx in a diagnostic assay has distinct advantages over conventional immunoassays as glycopolymers can bind to antigens in a multivalent capacity and are highly adaptable for mutated strains. GlycoGrip is a promising and generalizable alternative to costly, labor-intensive RT-PCR, and we envision it will be broadly useful, including for rural or low-income populations that are historically undertested and under-reported in infection statistics.
We expect biomimetic sensing technologies to have wide-reaching possibilities and be integrated into a variety of different platforms.

Ronit Freeman

Appearances