We have explored and validated two-particle (2P) microrheology at polydimethylsiloxane (oil)-water interfaces using confocal laser scanning microscopy. The loss and storage moduli of the oil-water interfaces as a function of frequency are quantified using different tracer particles. In contrast to one-particle interfacial microrheology in which the measured rheological results depend largely on the surface chemistry of tracer particles, the work here suggests that 2P tracking significantly minimizes the tracer particle effect. The viscous response dominates the oil-water interfaces and varies linearly with frequency, over the experimental range of the oil viscosity and frequency.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)