Selectively enhanced diffusion through polymer gels

Designing selective hydrogels that passively filter particles based on their interactions is a fundamental goal of nanotechnology. While it is conceptually straightforward for a particle’s interactions to facilitate its own retention (specific binding domains on the gel trap particles with complementary recognition sites), it is much more difficult for a particle to facilitate its own diffusion. This requires the binding interaction to locally reorganize the internal structure of the gel. We present a mechanism for this behavior and describe a theoretical model of the diffusion of interacting and non-interaction particles that is backed by numerical results. We also discuss how our results can lead to the design of artificial selective gels inspired by the Nuclear Pore Complex.