(620c) Investigation of the Motion of Patchy Particle Swimmers Near Fluid/Fluid and Solid/Liquid Interfaces

Recently, active colloids have been the subject of growing interest among scientists, due to their vast variety of applications including drug delivery, particle separation and Lab on a chip particle transport. Active colloids known as self-propelled particles swim in a hydrogen peroxide solution by decomposition of H₂O₂ into oxygen and H₂O. The asymmetric distribution of the product molecules around the particle leads to the particleâ??s autonomous motion. Many studies have focused on the motion and behavior of theses particles both in bulk and near interfaces, for example, some of these studies have examined the directionality of the motion of Janus particles and others have examined how the particles align with respect to the wall.

In this context, we have previously probed the motion of patchy particles with varying sizes near a solid/liquid interface. We found evidence that the patchy particlesâ?? rotational dynamics and their orientation with respect to the wall impact their swimming velocity and have attributed it to a preferential rotation of the particle around its swimming axis. [1]

Here, we present our approach to visualize the cap orientation of particles partially coated with platinum with respect to the fluid/fluid and solid/liquid interfaces. Further, we will show statistically relevant data on the orientation, fluctuation, and translation of colloidal patchy particles and their self-propulsion behavior in the presence of fluid/fluid and solid/liquid interfaces. The orientation and rotational motion of patchy particles will be analyzed and compared with respect to the type of interface they are interacting with.

[1] Z. Jalilvand, A. B. Pawar, and I. Kretzschmar, Patchy particle swimmers: a controlled self- diffusiophoretic motion, In Preparation, 2016.