Investigation of polymer diffusion in confined geometries using differential dynamic microscopy techniques

The fundamental understanding of polymer diffusion in confined geometries is important for industrial as well as broader applications such as transport in cell-like environments, improved drug delivery, and filtration. However, the study of polymer diffusion in such environments is often challenging due to the nanometer size scales of polymers and to the inhomogeneous geometry of the landscape. We have developed differential dynamic microscopy (DDM) techniques to investigate the dynamics of fluorescein tagged poly-l-lysine chains in confined environments in any arbitrary direction along textured surfaces. Using a curved surface, we can control the local confinement. The role of polymer molecular weight, concentration, confinement, and local geometry on polymers dynamics will be discussed.