Virtual MEchanics GAthering -MEGA- Seminar: Talk1 - Granular hydrogels as novel bioinks for 3D printing of artificial soft tissues; Talk2 - Immobilizing different types of drops in microfluidic trapping devices


Event details

Date and time 08.10.2020 16:1517:30  
Place and room Room Passcode: 349948
Speaker Matteo Hirsch & Michael Kessler (SMaL, EPFL)
Category Conferences - Seminars
Granular hydrogels as novel bioinks for 3D printing of artificial soft tissues, by Matteo Hirsch (SMaL, EPFL)
Hydrogels are among the first biomaterials expressly designed for their use in biomedicine. However, state-of-the-art applications of hydrogels are severely limited because they are typically either too soft or too brittle such that they cannot be used for load-bearing applications. At present, synthetic hydrogels are still far from reaching mechanical performances similar to that of their biological counterparts. One of the main reasons behind this difference is their poor internal arrangement. Indeed, nature is able to fabricate soft biological tissues encompassing highly ordered, hierarchical structures with locally varying compositions. Inspired by nature, we propose to use microgels as building blocks for the fabrication of 3D printed granular materials. Moreover, we investigate the effect of different processing parameters on the rheological behavior of jammed microgel solutions and on the mechanical performance of granular hydrogels.

Immobilizing different types of drops in microfluidic trapping devices, by Michael Kessler (SMaL, EPFL)
Many natural materials display unique mechanical properties that are, at least in parts, a result of the locally varying compositions of these materials. Bio-inspired materials usually cannot reach similar sets of mechanical properties than their natural counterparts. A contributing reason for this difference is that they typically possess homogeneous compositions. A possibility to fabricate soft, structured materials with locally varying compositions is the use of reagent-loaded drops as building blocks. In my talk, I will present a microfluidic device that allows immobilization of drops loaded with different reagents at well-defined positions using capillary trapping. I will show how we can vary the trapping force of traps to achieve a selective immobilization of only one type of drops. I will further present a mathematical model that predicts the trapping strength of traps depending on their geometry, which facilitates the design of such devices. To conclude, I will demonstrate an example of how immobilized drops can be transformed into soft materials with locally varying composition. This technology likely opens up new possibilities for the design of structured, load-bearing hydrogels, as well as for the next generation of soft actuators and sensors.

Practical information

  • General public
  • Free


  • MEGA.Seminar Organizing Committee


Solids Structures Fluids