A quartz crystal microbalance (QCM) is a device which uses the piezoelectric ability of quartz crystals to track mass changes due to a shift in the resonance frequency of the crystal. This allows for very sensitive mass measurement at the surface of the crystal. Originally used in vacuums to measure thin films, lately the QCM is also applied in liquid environments. The Q-sense E4 system is specifically designed to work in liquid environments. Its main features are the ability to detect mass changes in the nanogram range and to investigate structural properties. This is all done in situ, in real time and label free providing the means to study the kinetics at the surface. The system is able to measure 4 crystals parallel at the same time. All crystals are temperature controlled with a range of 20°C – 40°C. Liquid measurements can be performed in a static cell holder of with a flow (peristaltic pump with a minimum of 50 µL/min and a maximum of 1 ml/min). The Q-sense system is, in contrast to other QCMs, capable of measuring the dissipation of the crystals which gives information about the rigidity of the layer and gives a more clear view on the changes occurring at the surface then just mass change.
The Q-sense can be very useful in different fields: Proteins interactions, polymer changes, cells/bacteria, surfactants/cleaning of surfaces, Molecular Imprinted Polymers, etc