Pickering Emulsions
As novel emulsifiers, the use of nanostructured particles allows the preparation of solid-stabilized oil/water or water/oil emulsions (“Pickering emulsions”). By the choice of the nanoparticle material and shell, the properties of the emulsion droplets can be adjusted. Thermo- and magnetoresponsive solid-stabilized o/w emulsions are obtained by coating superparamagnetic nanoparticles with polymers with LCST- or UCST behavior in one of the liquid phases (Figure 1).1
These emulsions allow the remote manipulation of the droplets by temperature - addressing the shell, and/or external magnetic fields - addressing the magnetic core. (Figure 2).
Such systems are of interest for the encapsulation of lipophilic (o/w) or hydrophilic (w/o) substances, their magnetic transport and release upon an external stimulus. So-called Janus particles can be produced with the help of Pickering emulsions.2 These are particles with two or more distinct types of properties, for example a particle with two hemispheres bearing different functional groups (Figure 3). Janus particles are useful as building blocks for supraparticular assemblies, as surfactants or as nanoswimmers in a fuel solution.
