Apparent Microrheology of Oil-Water Interfaces

We use Pickering emulsions as a template to investigate the dynamics of charged microparticles at polydimethylsiloxane (oil) - water interfaces using confocal laser scanning microscopy. More importantly, we have explored the potential of developing one-particle and two-particle microrheology at liquid-liquid interfaces. The complex, loss, and storage moduli of oil-water interfaces as a function of frequency measured from microrheology are compared with those of bulk oils measured from a conventional rheometer and developed bulk microrheology. The nature of the tracer particles plays an important role in one-particle microrheology at liquid-liquid interfaces. We are currently comparing the results of one-particle vs. two-particle microrheology.