Polish scientists are developing a simple corona screening test which can even be used at home. A test like this is very important if large groups of people are soon to be tested at airports and large train stations.
At present there are only two type of tests. The first is the so-called “Real time PCR test.” This test detects the virus’s genetic material in the sample taken from the person under examination. This RT-PCR test has one advantage in that it is highly reliable. However, it also has several major disadvantages as well. It takes too long, from 3 hours up to as much as 18 hours. And it must be performed by trained staff with specialized equipment and in specialized labs. And, of course, it is expensive.
The second type is immunoassay. This type of testing entails searching for antibodies that the human body produces against the virus. This test is much cheaper, much quicker (it takes as little as 15 minutes to run one) and much easier to use. But there is one huge disadvantage: this type of test is not very reliable. For example, it can give false positive results in someone who has recently had the flu. Or vice versa, give false negative results in people with weakened immune systems. Or wrong results if taken too early on after the initial infection when the body hasn’t yet had time to respond to the viral infection.
New approach to coronavirus test
A MedTech start-up SensDx is working together with Professor Krzysztof Pyrć from the Małopolska Centre of Biotechnology at Jagiellonian University (Poland) on a new type of SARS-CoV-2 test that will be fast, easy to use and reliable. “It should be the ideal test for airports, borders and everywhere where there are large groups of people,” according to Katarzyna Pala. She’s the director of business development at SensDx.
Unlike the RT-PCR test or immunoassay, the new test will not focus on human antibodies or the virus’s RNA but will detect the virus’s protein instead. The scientists have just reached their first milestone. “We have selected a protein that we are going to use in our tests. It is a protein that builds a capsid of the virus (the protein shell of a virus – ed.) It is what’s referred to as a conservative protein, one that doesn’t mutate. Yet at the same time it is unique and typical only of this virus. It enables us to detect the coronavirus at the very early stage of infection, before a patient may have any symptoms,” Katarzyna Pala explains.
Patented technology for medical sensors
Several years ago, SensDx had invented and patented their technology of ultra-sensitive medical sensors that can be used even at home. Their diagnostic tests are comprised of two parts. The first one is an electronic reader. The second one involves electrodes modified with a special biological layer that recognize virus or bacteria surface markers. This is at the heart of the technology. Thanks to this test, it is possible to identify what viruses or bacteria cause infection in a patient. With SensDx’s influenza test, results are ready within 3-5 minutes and their reliability is comparable to the RT-PCR test. The same technology will be used in the new COVID-19 tests.
Currently the scientists are working on the next step, namely selecting the biofilm. In simple terms, it’s a mixture of various molecules that will be used to bind on to pre-selected proteins of the SARS-CoV-2 virus. “It works like a key and a lock. The protein is the lock. Now we are looking for a key that will match that lock,” Katarzyna Pala adds. When the biofilm is ready, the company will need to test it once more to check that it doesn’t react to other proteins or viruses. If this test is successful, the biofilm will be placed on the electrodes and the prototype test will be tested. First, in the company’s lab, then in a “safe environment,” Katarzyna Pala states.
The start-up expects that the prototype will be ready by the end of May and validated in June.