Experimental Soft Condensed Matter Group Harvard University, Prof. D. A. Weitz Cool Picture of the Moment

COLLOIDSOMES Colloidosomes are spherical shells of micron-sized particles that are formed by introducing colloidal particles to emulsion droplet templates. These pictures were taken by Ming Hsu, who is using colloidosomes to form encapsulation structures which exhibit selective permeability and to study interparticle interactions at fluid-fluid interfaces. Most of the pictures were taken with a Scanning Electron Microscope.

This is an optical microscope image of a colloidosome encapsulating oil in aqueous solution. The colloidosome has not been sintered or dried. The beads are about 1 micron in diameter. Scale bar = 10 microns.
	This is a scanning electron micrograph of a colloidosome which has been sintered and dried. In contrast to the unsintered colloidosome above, the beads have fused together on the surface of the colloidosome, forming an impermeable shell. Scale bar = 2 microns.
Sintering imparts striking elastic properties to the colloidosome. On the right we observe that the bead shell can sustain a radius of curvature of a few bead diameters. Scale bar = 5 microns.
	However, not all colloidosomes can withstand the stresses encountered during the drying process. Scale bar = 2 microns.

Past cool pictures...