Quartz crystal microbalance with dissipation monitoring (QCM-D) is an acoustic surface sensitive technique that measures changes in resonance frequency and energy dissipation of a piezoelectric quartz crystal sensor. The sensor surface can be coated with various materials and can detect changes in liquid media up to ~250 nm from the surface. NOTE: Users need to purchase the desired sensor crystals themselves.
The hydrated thickness and surface mass coverage (including any coupled solvent) of rigidly deposited or adsorbing materials can be readily determined (assuming the density is known) using the Sauerbrey equation.
The response from "soft" viscoelastic layers can also be modelled to determine thickness, viscosity and elasticity using the Voigt model (available in the instrument software).
We have special flow cells for combined QCM-D and ellipsometry/electrochemistry. The correct reference electrode need to be acquired by the users themselves for the electrochemistry flow cell (see document link for correct electrode). Contact the tool responsible if you wish to measure in organic solvents (other than ethanol).
General features according to manufacturer:
- Tracking mass changes: molecular layers forming on the sensor surfaces are sensed at the nanogram level.
- Viscoelastic properties: structural changes in the adsorbed layers are monitored simultaneously, through the D-factor reading.
- Real-time presentation of data: what happens on the surfaces, evaluation of kinetics, etc, is displayed using QSoft 401 software.
- Label free: there is no need for labeling of molecules.
- Flexible choice of surfaces: any surface that can be applied as a thin film can be used, such as metals, polymers and chemically modified surfaces.
- Flow measurements: the Q-Sense flow modules are specifically designed for flow measurements in a temperature-controlled environment.
- 4-Sensor chamber: the 4 flow modules can be either connected in a series mode, or run parallel.
- Build-on options for combination measurements: Combine with simultaneous electrochemistry, ellipsometry, microscopy and more (additional hardware necessary).
- Easy cleaning: all parts exposed to liquid can be removed and immersed in cleaning baths.