Summary

The ability to deliver drugs within the central nervous system (CNS) is one of the most difficult tasks where current approaches only enable a small percentage of the injected dose to cross the blood brain barrier. The CNS consumes an important amount of the glucose available in our body, therefore, drug delivery carriers that spontaneously moves up glucose gradients could, in principle, increase the efficiency of drug release within the CNS. Here, we study the potential of asymmetric active polymersomes to spontaneously move up glucose sources. We modelized a two-­dimensional polymersome that has a patch of membrane functionalized to react to glucose. A reactive patch creates an asymmetric distribution of products along the membrane that induces liquid flow in the polymersome surroundings that eventually propels it. This process is known as self-­diffusiophoresis. We implement the key physical elements that drives this phoretic process to find the optimal characteristics polymersomes should have to reach the CNS. These characteristics includes: patch size, polymersome radius, temperature, gradient stiffness, reaction kinetics etc. It was found out that in order to achieve chemotactic motion particles should have the whole membrane reactive and a radius size closer to the micrometric scale rather than the nanometric scale.

In summary, designing and understanding of systems that reacts to glucose gradients will set a completely new trend in the design of drug delivery systems, embracing the new advances being proposed in active colloids.