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• Q-Sense E4
  • Complete E4 System
  • Specifications Q-Sense E4
  • 4-sensor chamber
  • Data analysis
• Q-Sense E1
• Q-Sense Modules
• Q-Sense Sensors
• Q-Accessories

Data analysis

The Q-Sense software package includes extensive possibilities to analyze and interpret measurement data, from graphing different plots to advanced modeling. Typical output data are:

• Mass and thickness vs. time
• Structural (viscoelastic) properties vs. time
• Kinetic constants

Other features include temperature ramping, export of data and plots, and the ability to enter your own custom mathematical models.

For more information on our applications, products and the QCM-D technology, you are always welcome to contact us.

Plotting of raw data
When raw data files are opened, the data may be conveniently formatted to allow plotting of the raw data.

 

 

This plot shows the adsorption of lipid vesicles and thereafter the formation of a supported lipid bilayer. The peaks in the data indicate that the initially adsorbed, intact vesicles have started to rupture, releasing the contained water and forming a supported lipid bilayer. The initially adsorbed, intact vesicles form a soft, water-rich film (higher dissipation as shown in the orange curves), while the resulting lipid bilayer, after rupture and spreading of the vesicles, is thin and rigid (low dissipation).

Fitting to a viscoelastic model
Using frequency and dissipation data from several harmonics, raw data can be fitted to a viscoelastic model included in the software.

 

In the modeling center, intervals of thickness, viscosity and shear modules are entered in the software. The model will then automatically find the best fit.

The software performs a mathematical fit that calculates the thickness, viscosity and elasticity of the adsorbed layer. Fitted data are shown in the squares above.

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Comparing data from Sauerbrey and the viscoelastic model
In this example, the intact vesicles form a soft layer, which means that the Sauerbrey relation, due to the energy losses within the layer, underestimates the mass.

As can be seen, for the soft layer of vesicles, the thickness value from the viscoelastic model is larger than that obtained from the Sauerbrey relation . However, the two methods each give the same response for the low dissipation lipid bilayer film.

The modeling tool has been used in many publications.