Rapid coronatesting could be enabled by plasmonics

In the midst of crisis, innovation is thriving. When entire communities of business and research pull together to deal with a single issue, amazing things can happen. We are excited to see that our favourites – the plasmonic nanoparticles – now appear to be one of the promising leads for new corona-testing technology.Plasmonic nanoparticles are tiny metallic particles that have unique optical properties, and extraordinary efficiency at absorbing and scattering light. This is not only useful for transparent solar cells, but also for development of biological and chemical sensors.

Last week a team of researchers based at ETH Zurich published a study prompted by the ongoing pandemic on how a new kind of plasmonic biosensor could provide a fast and sensitive alternative to the standard RT-PCR analysis for COVID-19. Faster tests would be very valuable in a situation where a large part of the population needs to be tested.

This new sensor utilizes plasmonic nanoparticles and combines two of their features, localized surface plasmon resonance (LSPR) and the plasmonic photothermal (PPT) effect. LSPR is a phenomena where incoming light cause surface electrons to oscillate. These oscillations are very sensitive to variations on the molecular level, which makes them useful for detection of micro- and nanoscale analytes, such as viruses.
Even if this new sensor is promising, there remains some practical issues. An article from last year on the American Association for Clinical Chemistry’s news section highlights that biosensors using surface plasmon resonance are expensive and only made by a handful of companies, and they primarily design and market their instruments for academic and pharmaceutical laboratories.

A different approach is being developed by the American company Nanopartz, that is aiming for COVID-19 detection in under 1 minute with their novel “plasmonic PCR”, proposed as a rapid and low-cost PCR. It is based on laser heating of plasmonic gold nanoparticles suspended in the PCR tube, where detection is done by measuring the optical absorption of the suspended nanoparticles.

Whichever technologies eventually turn out to be the most useful to tackle the pandemic, it is indeed encouraging and inspiring to see the efforts and innovation from all different sides. At Peafowl Solar Power, we keep working on our core mission of sustainable buildings and cities with adapted routines for social distancing. Meanwhile, we are cheering on our plasmonic colleagues in the sensor field and we stand ready to support with nanoparticles if needed for the companies trying to commercialise plasmonic driven biosensors and PCR.
We are cheering on our plasmonic colleagues in the sensor field and we stand ready to support with nanoparticles if needed