Colloids at Fluid Interfaces

Colloids at interfaces: Pinned down.

In 1903 Walter Ramsden found that an air bubble placed in a liquid suspension of microscopic particles “can be seen to pick up the particles ... and to retain them obstinately ...”1 Ramsden had discovered the strong affinity of colloidal particles to fluid interfaces, an affinity that a century later can be harnessed to make microstructured materials such as Pickering emulsions, colloidosomes a...

Colloids at Liquid-liquid Interfaces

Ellipsoidal particles at fluid interfaces.

For partially wetting, ellipsoidal colloids trapped at a fluid interface, their effective, interface-mediated interactions of capillary and fluctuation-induced type are analyzed. For contact angles different from 90( degrees ) , static interface deformations arise which lead to anisotropic capillary forces that are substantial already for micrometer-sized particles. The capillary problem is sol...

Trapping and assembly of living colloids at water-water interfaces.

We study the assembly of inert and living colloids in a two-phase water-water system that provides an environment that can sustain bacteria, providing a new structure with rich potential to confine and structure microbial communities. The water-water system, formed via phase separation of a casein and xanthan mixture, forms a 3-D structure of coexisting casein-rich and xanthan-rich phases. Fluo...

Behavior of cells at fluid interfaces.

We have cultured the murine cell lines 3T3-L1 and SV-T2 using as a substrate the layer of denatured protein that forms at the phase boundary between culture medium and fluorocarbon fluids. The growth patterns observed on these interfaces differ from those seen on conventional solid substrates. Depending on the cell strain and the composition of the fluorocarbon fluid, cells will tend to clump i...