Chemotactic synthetic vesicles: design and applications in blood brain barrier crossing

One of the most promising tasks is the ability to engineer nanocarriers that can autonomously navigate within tissues and organs, accessing nearly every site of the human body guided by endogenous chemical gradients. Here we report a fully synthetic, organic, nanoscopic system that exhibits attractive chemotaxis driven by enzymatic conversion of glucose. We achieve this by encapsulating glucose oxidase, alone or in combination with catalase, into nanoscopic and biocompatible asymmetric polymer vesicles (known as polymersomes). We show that these vesicles self-propel in response to an external gradient of glucose by inducing a slip velocity on their surface, which makes them move in an extremely sensitive way towards higher concentration regions. We finally demonstrate that the chemotactic behaviour of these nanoswimmers enables a four-fold increase in penetration to the brain compared to non-chemotactic systems.