Polyelectrolyte multilayer microcapsules as smart carriers for controlled drug delivery.

Nanomedicine aims to develop smart therapeutic tools and strategies for human health. In this context, polyelectrolyte multilayer microcapsules (PEM) may serve as excellent carriers for drug delivery. Herein, we describe the synthesis, the functionalization and the bioactivity of optical-responsive PEMs engineered to achieve spatio-temporal control of a specific cell signalling pathway controlling animal development. PEMs, made by layer-by-layer assembly of non-degradable polymers, were filled with bioactive molecules and tested in vivo by using the freshwater polyp Hydra vulgaris as a simple invertebrate model. Immediately after uptake, the capsules were opened on demand by light into the animal cells. Phenotypical, cellular and molecular analysis of irradiated animals demonstrated the activation of the desired cell signalling. In conclusion, our outstanding approach paves the way for upcoming therapies based on remote control of drug delivery.