Rapid Cellulose-Based Serological and Diagnostic Tests for COVID-19

The alarming spread of the corona virus, SARS-CoV-2, has raised emergency public health concern, globally. With no treatment and vaccine available, the best control is to rapidly diagnose infected individuals and apply quarantine period to prevent further viral transmission. However the symptoms caused by SARS-CoV-2 infections may be mild or unnoticeable. Patients may not know they have been infected and may have spread the disease unknowingly.

Current diagnostic tests depend largely on the detection of a viral genomic profile using RT-PCR. However this method often lacks accuracy for patients with mild or no symptoms. Serological test for detection of antibodies against SARS-CoV-2 virus is preferred for diagnosis of mild symptomatic or asymptomatic patients. Although RT-PCR and serological tests provide satisfy results, they require up to 5 days of turn-around-time. Furthermore, they demand skilled personnel and special laboratory facilities to run the tests, thereby restricting the tests only to hospitals and laboratories. Rapid diagnostic tests (RDTs) that can be operated outside of hospitals are urgently desired to screen as many people as possible to timely triage SARS-CoV-2 infected cases and prevent the virus from spreading.

We propose development of two types of paper-based RDTs that requires only 10 minutes operation time and can be operated outside of hospitals. (i) Serological test to detect antibodies against SARS-CoV-2 and (ii) RDTs to detect SARS-CoV-2 biomarkers. Protein engineering technologies will be used to (i) immobilize high densities of fragments of SARS-CoV-2 S protein within a cellulose matrix to capture SARS-CoV-2 antibodies and (ii) to create new binder proteins to capture the SARS-CoV-2 biomarkers, N and S proteins. With our technologies, the tests will be more robust than standard serological and antibody-based tests and therefore can be deployed for field applications without the need for temperature controlled facilities, facilitating a larger scale of disease screening.