We follow the gelation process of protein microparticles directly in real space. Unlike the individual proteins, the protein microparticles are large enough (around two micrometers) to be seen with an optical microscope, and yet, they exhibit protein-like interactions.
We use cold-set acid-induced gelation to separate the early pre-aggregation stages from the later clustering and gelation stages. This allows us to follow the advanced stages of aggregation and the gelation process alone. To obtain insight how the gel emerges and obtains its stability, we follow the process in three dimensions with particle-scale resolution. The pictures above show three-dimensional reconstructions of the system after 6 (left) and 9 hours (right). Colour indicates the local connectivity (number of bonded neighbours) of a particle. This connectivity increases, while the structure coarsens.