rpiekarski@wavejobs.eu 
The COVID-19 epidemic is a phenomenon that humanity has never faced before. It has touched every aspect of our existence, from health (physical and mental) to economics and geopolitics. It is no exaggeration to say that, at the moment, all fields of science are busy making sense of what is happening and searching for solutions to the various crises that the covid has provoked.
Photonics, among other sciences, has also made and continues to make a significant contribution to the global effort to combat the coronavirus. Two key practical questions to which photonics is trying to find simple and effective answers are
- How to quickly and effectively detect the presence of the virus in the human body?
- How to reduce the risk of its spread?
Disinfection
UV-C radiation as a method for eliminating coronavirus
Known for many years, the UV method is widely used in hospitals and public places in many countries. It is especially effective in killing viruses from open surfaces and air. UV-C acts directly on DNA and RNA, changing their chemical structure and, as a result, inactivating the infectivity of viruses.
Although UV-C cannot and should not replace thermal and chemical disinfection in every scenario, it can be used effectively in many situations where thermal and chemical methods are not possible or feasible. In addition, given the low consumable requirements, UV-C is compatible with a wide range of working media and can be an alternative method.
At the moment, the following ways of disinfection with UV are being developed:
- re-equipping standard biosafety cabinets;
- creating closed portable boxes with one UV-C source or arrays of UV-C sources;
- building large rooms with intense UV sources;
- сreating robots with mobile base and fixed vertical UV-C sources (some of these systems existed on a commercial basis before the COVID-19 pandemic, motivated by the need to disinfect hospital premises).
You can read more about these technologies in this article.
Diagnostic
Tests
To diagnose active COVID-19 infections, the main testing protocols involve the use of a process known as reverse transcription polymerase chain reaction (RT-PCR) that uses photonic technologies such as LEDs, photodetectors, optical filters.
One of the most effective antibody tests is the enzyme-linked immunosorbent assay (ELISA). It is a powerful tool for determining if someone has previously been infected and tracking the effectiveness of vaccinations. This test requires the same optical components as PCR testing systems.
Thus, each RT-PCR antigen test and ELISA antibody test are not only indirectly dependent on photonics, but are in fact an optical assay.
Rapid screening at points of care
The importance of ELISA and PCR cannot be underestimated, but unfortunately neither of these methods are suitable for rapid point-of-care (POC) testing. The total measurement time may take several hours. Fortunately, even before the current pandemic, modern spectroscopic techniques paved the way for rapid medical diagnosis. The two most promising POC screening methods are surface plasmon resonance (SPR) sensors and surface-enhanced Raman spectroscopy (SERS) immunoassays, which are also advancements in photonics. You can read more about these technologies here.
New diagnostic technologies
At present, photonics, among other things, is focused on the development of biological and chemical sensors for the diagnosis of a wide range of diseases. New technologies directly use the interaction of light and matter to detect specific pathogens.
Integrated photonic biosensors demonstrate their capabilities in the analysis of clinically relevant materials and the specific detection of proteins, nucleic acids or pathogens in human body fluids (serum, urine, saliva, etc.). They also serve as the basis for portable diagnostic systems for the detection of the viral pathogens of Ebola and malaria. Their effectiveness and versatility make photonic biosensor technologies an attractive solution for new COVID-19 diagnostics.
Treatment
New developments in photonics are also contributing to the treatment of coronavirus and, in particular, helping to alleviate the disease.
Scientists are
- developing new methods to predict the severity of COVID-19;
- studying the effects of photobiomodulation therapy in combination with a static magnetic field in patients with severe COVID-19 who require intubation;
- investigating the reliability of body temperature measurements with non-contact infrared spot thermometers;
- studying the method of probe-based confocal laser endomicroscopy;
- and many others.
Below we have prepared a selection of materials where you can get acquainted with the latest developments in photonics in the field of combating the coronavirus epidemic.:
- https://mlsystem.pl/potwierdzona-skutecznosc-covid-detectora-ml-system/
- https://www.laserfocusworld.com/biooptics/article/14188801/optics-and-photonics-enable-the-fight-against-covid19
- https://www.photonics-bretagne.com/en/photonics-intelligence-letter-special-edition-covid-19/
- https://www.osa-opn.org/home/newsroom/2020/september/chasing_covid-19_with_photonics/
- https://aip.scitation.org/doi/10.1063/5.0021270
- https://www.mdpi.com/journal/photonics/special_issues/biophotonics_for_covid19
- https://www.ipgphotonics.com/en/news
Yuliya Hoika, journalist, branding and communication specialist.
