While the world is eagerly waiting for a vaccine, one of the problems that still exists is an effective COVID-19 test to determine its infection in early stages. The current COVID antibody testing is effective three-four days after the onset of infection; by that time the person has already spread the virus to others. On the other hand, the antigen-based tests to detect coronavirus proteins in the saliva have poor sensitivity, forcing people to go for expensive and time-consuming RT-PCR-based standard tests.
Early diagnosis is important in the management and control of COVID-19, says V. V. Raghavendra Sai, Associate Professor of Biomedical Engineering, Department of Applied Mechanics, IIT Madras.
The Biosensors Laboratory in IIT Madras headed by Raghavendra Sai is in the process of developing an efficient and sensitive COVID-19 diagnostic test. A prototype has already been developed.
The lab was working for the last nine years on a fiber optic biosensor platform for the detection of bacterial toxin in urine for tuberculosis diagnosis.
This technology is now being modified to determine antigen in the saliva for COVID-19 infection. IIT Madras is conducting the research in collaboration with Ricovr Healthcare Inc., USA and Jitendra Satija at VIT Vellore for COVID-19 diagnosis.
"The sensor is designed to detect the SARS-CoV-2related proteins in a person's saliva and gives a digital readout," says Sai.
The biosensor platform is in the form of a handheld device, removing the need for any specialised apparatus, reducing the cost of COVID testing and showing results in five minutes. This technology has already been patented by IIT Madras and their US-based collaborator, Ricovr Healthcare Inc.
Sai adds: "This technology is different from the other molecular and antibody-based tests because it can detect the slightest presence of active viral particles on the spot making it accurate. We aim to realise an affordable and reliable COVID diagnosis that would be cheaper than RT-PCR and sensitive than the existing paper-based point-of-care antigen kits."
Point-of-care or near-patient testing is a type of medical diagnostic test that enables accurate, real-time, laboratory-quality diagnostic test results within minutes. Testing at the point of care increases the efficiency of diagnosis and testing process, and helps ensure that patients are receiving quality care and instant results rather than waiting for one-two days.
IIT Madras has tied up with the US-based RICOVR Healthcare to bring the Point-of-care Fiber-optic Biosensor (P-FAB) Device from the lab to the market. The technology will take another three-six months for commercialisation and is expected to have a much wider scope of applications beyond COVID-19 diagnosis, such as disease diagnosis in emergency wards and primary healthcare centres.
The project has received a research grant from Science and Engineering Research Board (SERB), a Department of Science and Technology (DST) unit under the Government of India. They have also received an 'Ignition Grants' Award from the US India Science and Technology Endowment Fund (USISTEF), a joint fund established by the US and India to promote innovation. This financial support is intended to bring the technology from the research laboratory to the market.