| abstract |
The present invention generally relates to ferrofluid emulsions and/or magnetically susceptible particles. In some cases, such emulsions and particles can be produced in a microfluidic system. In one aspect, an emulsion containing a ferrofluid can be produced, and in certain cases, the emulsion is substantially monodisperse. In some embodiments, the emulsion also contains a precursor that can be solidified, for example, a polymer precursor. The emulsion may also contain an emulsion stabilizing agent and/or a viscous agent. In another aspect of the present invention, the ferrofluid emulsion may be hardened to form particles, for example, by removing a fluid from the emulsion and/or by solidifying a precursor, such as a polymer precursor, around the emulsion. For example, the ferrofluid may be formed from an organic solvent containing nanoparticles, and the organic solvent removed such that the nanoparticles form magnetically susceptible particles. The particles may also be further manipulated, for example, using a magnet. For instance, in one set of embodiments, the particles may be moved from one fluid stream to another fluid stream using the magnet, for example, for further processing, reaction, analysis, etc., of the particles. In some cases, the particles may be formed 'on demand,' e.g., for a variety of different applications. |