Dravid, Professor of Materials Science and Engineering, Northwestern University, and Director of the NUANCE Center, "This is one way to monitor what goes on in the cell without having to lyse it open." In this process, high-frequency acoustic waves from a piezoelectric crystal are launched upward through a specimen while similar acoustic waves of a slightly different wavelength are aimed downward from the scanning probe microscopy cantilever (also a piezoelectric crystal transducer
The specificity and selectivity provided by these enzymes were used along with the amplifying capacity of a quartz crystal transducer
. Researchers placed the piezoelectric quartz crystal in an improved electrical oscillator circuit and monitored changes in the vibrational resonant frequency.