Gel formation in confined geometries and hierarchical structures
The vision of the project is to control release of active molecules by design of the internal droplet microstructure. The goal is to determine the mechanisms controlling structure evolution of kinetically trapped phase separated biopolymer mixtures in confinement.
Confocal microscopy and image analysis have been used to characterize confinement size and temperature kinetics during gelation and phase separation in mixtures of gelatine and maltodextrin. It has been found microstructures similar to the bulk are formed in larger droplets (>50 mm). In contrast, confinement strongly influences the initiation of phase separation and the microstructure in smaller droplets. An elastic Lennard-Jones model has been used to simulate the confinement structures. Diffusion of FITC-dextran has been determined using rectangle-FRAP. Droplets with very reproducible internal microstructures have been mass-produced by temperature controlled microfluidics and variations in the subsequent cooling kinetics. The project collaborates with Peter Fischer, and Elisabeth Rondeau, ETH, on microfluidics and production of phase separated hydrogel droplets, and Martin Kröger and Orit Peleg, ETH, on structure modelling of phase separation in confinements.
Last modified: September 19, 2011