Nanocapsules: Ultrastable Liquid–Liquid Interface as Viable Route for Controlled Deposition of Biodegradable Polymer Nanocapsules

Liquid-liquid interfaces are highly dynamic and characterized by an elevated interfacial tension as compared to solid-liquid interfaces. Therefore, they are gaining an increasing interest as viable templates for ordered assembly of molecules and nanoparticles. However, liquid-liquid interfaces are more difficult to handle compared to solid-liquid interfaces; their intrinsic instability may affect the assembly process, especially in the case of multiple deposition. Indeed, some attempts have been made in the deposition of polymer multilayers at liquid-liquid interfaces, but with limited control over size and stability. This study reports on the preparation of an ultrastable liquid-liquid interface based on an O/W secondary miniemulsion and its possible use as a template for the self-assembly of polymeric multilayer nanocapsules. Such polymer nanocapsules are made of entirely biodegradable materials, with highly controlled size-well under 200 nm- and multi-compartment and multifunctional features enriching their field of application in drug delivery, as well as in other bionanotechnology fields.