CONVAT project aims for point-of-care Covid-19 diagnosis

08 Apr 2020

European research group will develop optical biosensor technology.

A project launched at the Catalan Institute of Nanoscience and Nanotechnology (ICN2) intends to develop a point-of-care platform for rapid diagnosis and monitoring of coronavirus.

The CONVAT project will see the development of a new rapid non-invasive optical biosensor demonstrator, able to detect Covid-19 in humans as soon as it is present in the body. Although officially a two-year project, CONVAT is based on existing expertise within ICN2, and results are expected to be produced in less than a year.

CONVAT is one example of the substantial European research effort rapidly taking shape to counter the Covid-19 pandemic. In January the European Commission published an express €10 million call for research proposals, which was then boosted by an additional €37.5 million of funding for urgently needed study of Covid-19 vaccine development, treatment and diagnostics.

A total of €48.5 million from Horizon 2020 has ultimately been allocated to the effort as of early April 2020, with 18 research projects given the green light, CONVAT being one of them.

The project is coordinated by Laura Lechuga's Nanobiosensors and Bioanalytical Applications Group at ICN2, alongside project partners at the Universities of Barcelona and Marseille, and the Italian National Institute of Infectious Diseases (INMI), which was among the first centers to sequence the SARS-CoV-2 coronavirus.

CONVAT will provide a new device based on optical biosensor nanotechnology that will allow the detection of coronavirus directly, without the need for testing in centralized clinical laboratories. This new technology could also quickly identify whether it is a common coronavirus or flu infection.

Lechuga's group has previously studied routes to point-of-care sensing devices able to identify bacterial conditions such as sepsis, or cancer markers. Those platforms have analyzed blood plasma extracted from a patient, assessing the sample via optical interferometry using bespoke microarrays and nanostructured substrates.

Detection in 30 minutes

Having already created six working laboratory demonstrators for these other applications, the ICN2 team believes that, with further adaptation and testing, the same ultrasensitive detector technology should be able to test nasal or saliva swab samples for coronavirus, and detect infections in patients with a small amount of the virus.

"We are currently integrating all the instrumentation in a portable 25 x 15 x 25 cm box with a tablet control," said Lechuga. "At present our detector is user-friendly, with sample preparation being the only technical expertise required, and could be widely deployed for GPs or nurses to test patients."

The project's optical technology could prove crucial in the rapid assessment of coronavirus cases, exploiting the change in refractive index that occurs when prepared receptors, such as antibodies or DNA strands, recognize the antigens particular to the Covid-19 protein shell.

"Our interferometric technology is unique for biosensing," commented Lechuga.

"A bimodal waveguide interferometer uses two modes of a light beam at the visible wavelength traveling in a single waveguide. The light interacts with analytes during their travel, and at the end of the bimodal waveguide we record the interference between both light modes. The signal is collected with a photodetector and processed by electronics, all instantly in real-time."

The existing ICN2 technology will now be optimized and evaluated for viral RNA analysis in a multiplexed format, for more accurate diagnosis and identification of virus strains among different coronaviruses and other clinically relevant viruses. The hope is that the sensor will ultimately allow the detection of coronavirus in about 30 minutes.

CONVAT also aims to extend beyond the current pandemic and the diagnosis of human patients. It intends to use the new biosensor for the analysis of different types of coronavirus present in reservoir animals, such as bats, in order to observe and monitor possible evolution of these viruses and prevent future outbreaks.