Have you ever heard of an acoustic levitator? Acoustic levitation uses acoustic radiation pressure from high-intensity sound waves in order to suspend matter in the air against gravity. Sounds cool, huh? Well, new research published in ACS' Analytical Chemistry describes the development in this phenomenon that may allow researchers to levitate small objects and matter, without touching them.
Conventional devices used to levitate small objects require that the object has specific properties, i.e. an electric charge or magnetism. Acoustic levitation, on the other hand, does not require such properties in an object because it uses sound waves.
However, acoustic levitation has its own complications. The current devices used to enable acoustic levitation and the mixing of single particles or droplets are challenging to observe and record measurements from while a chemical reaction is actually happening.
In order to address this dilemma, researcher Stephen Brotton and Ralf Kaise developed a method that allows for the “contactless control of two chemically distinct droplets.” This technique relies on probes to follow the reaction as the droplets combine.
Eureka Alert explains the process: “The team made an acoustic levitator and suspended two droplets in it, one above the other. Then, they made the upper droplet oscillate by varying the amplitude of the sound wave. The oscillating upper droplet merged with the lower droplet, and the resulting chemical reaction was monitored with infrared, Raman, and ultraviolet-visible spectroscopies.”
The huge perk of this is that contact-free experiments make it possible to get rid of any containers or handling that might affect the outcome of the experiment. The researchers say that the technique has myriad applications and could be used in chemical experiments in material sciences, medicinal chemistry, and planetary science.