Mechanical testing of soft biological tissues


In the soft tissue biomechanics and engineering (STBE) group, many projects are aimed at tissue engineering of heart valves. We are interested in how these tissue grow and remodel after implantation in a patient. To this end, we have developed a bioreactor in which we can culture representative tissue engineered constructs, while mimicking physiological conditions, and follow their development over time. An important parameter which will inevitably change during development is the tissue’s mechanical properties. By means of a classical bulge test, while tracking the tissue displacement non-destructively with ultrasound imaging, we are able to asses mechanical properties over time without sacrificing the constructs.

In this project, we would like to compare two methods of mechanical testing: our proposed (non-destructive) bulge test method, to a standard biaxial tensile test. The latter is the current golden standard in mechanical testing, but does require you to sacrifice your sample. If both methods give comparable results, the non-destructive nature of the proposed bulge test will have great advantages in future mechanical testing of soft biological tissues.

The primary objective of this project is to compare two methods for mechanical testing of biological samples. Initial pilot experiments can be performed with plastics (PDMS) or slaughterhouse material (pericardium, arteries), but ultimately real tissue engineered constructs will be cultured and tested. Second, students can vary certain parameters of the tested samples (thickness, anisotropy, culture time etc…) and study the effect on the mechanical properties.

Both students are encouraged to work together on some parts of the project. For example the measurements on the samples (dummy or tissue engineered) can be performed together, however both students need to write their own report based on their individual research question(s).

Prior knowledge: Matlab
Skills to be obtained: Cell culture, Tissue engineering, Mechanical testing, Ultrasound Imaging