A team of researchers has created an ultraportable device that uses sound waves to rapidly separate virus particles from more than 200 microliters of whole bloodor about the volume of a typical eye drop, in less than five minutes.
Changing the way of viral isolation
Only through studying viruses can we find ways to fight back with antiviral drugs and vaccines. Yet, a major barrier to isolating these small infectious vectors in saliva and other complex biological samples has hampered the understanding of how sialic acid affects infection. A new platform that uses sound waves to separate rare circulating viruses from other blood components can help pre-program immune responses to better target infections.
Its particular sound wave type, the Bessel beam, comes from its Bessel Beam Excitation Separation Technology (BEST). Listen to these custom soundwaves live-tune their resonant beats with the size of particles, effectively serving as an acoustic tweezers. The BEST platform with dual-perpendicular Bessel beams enables accurate isolation of viruses from both larger and smaller particles in human saliva samples.
This is a huge improvement on traditional methods, which usually involve long and cumbersome worksteps such as ultracentrifugation and cell culturing. These precise and rapid viral isolation technologies by the BEST platform can be applied at interrogation of unknown viruses, genetic sequence manipulation, and targeted therapeutic design.
Advancing Acoustofluidics to the Next Level
The long term success of the BEST platform will depend on acoustofluidics, the science of using sound waves to very precisely manipulate and sort particles in a liquid. Taking advantage of these properties NIST researchers designed a 4-D trapping technique based on Bessel beam which allows for virus isolation in a highly precise and versatile manner.
Like a pair of tweezers, Bessel beams manage to keep tight focus over very long distances. This enables the scientists to further adjust the wavelengths of the beams in order to hone into range particular particle sizes, differentiating viruses from other substances very precisely.
BEST is a rectangular chip that has sample loading inlet at one end, two outlets for the virus and waste stream along its length. When the sample goes through the chip, plate waves compress Bessel beams in a direction normal to the flow of particles, and these cage photons perform the essential function of sorting based on size. This method reduces the time required for virus isolation and has the potential to be scaled up for high-throughput applications.
Those human saliva samples packed with SARS-CoV-2 served as excellent guinea pigs for the researchers to demonstrate that 90% of the virus genetic material could be successfully isolated in the virus outlet (see Part B). This important advancement sets the stage for more precise and efficient research on a number of viral disorders, which could one day result in novel therapeutic interventions.
Conclusion
Excitingly, through the development of the BEST platform, a new era in virus isolation and study came into being. Using sound waves, researchers have developed a gentle, contact-free method for separating circulating tumour cells and virally-infected cells from live samples, which will help clinicians develop targeted therapies. This highly promising technology offers the opportunity to truly revolutionize our approach to the study and treatment of viral diseases, en route to global health and wellbeing.
