Sample Prep & Processing

Researchers have been culturing bacterial and eukaryotic cells for decades in an effort to elucidate their biological functions and to develop and evaluate treatments for disease. While culturing cells under atmospheric conditions may yield informative results, often these studies require an environment that more closely mimics the actual physiological climate.

In vivo, animal cells are exposed to oxygen concentrations that range from 1% to 12%. At normal atmospheric conditions, oxygen is present at a concentration of around 21%. Many anaerobic microorganisms cannot carry out proper metabolic processes in the presence of oxygen. In fact, atmospheric concentrations of oxygen are often toxic to these cells.

Sound as Energy

Energy comes in many forms. One of those is sound energy, which manifests as vibration. For example, we can hear a loud noise because receptor cells in our ears translate vibrations from sound energy into brain-bound electrical signals. Most sound waves lie outside our range of “hearing,” but produce energy nonetheless. In labs, this ultrasonic energy is used to agitate particles for the purpose of cleaning, mixing solutions, increasing dissolution rate, or to evaporate dissolved gasses from liquids.

Sound travels through air, liquids and solids. The less dense the medium, and the closer the source, the easier the sound waves move. Sound “frequency” is a measure of particle vibration: higher frequencies cause more vibration, and as you can imagine, carry greater strength. Sonicators used in labs are high-frequency instruments that operate at levels above what humans can hear. These ultrasonic waves are above 20 kHz, which is 20,000 cycles per second.