Controlling the Encapsulation of Charged Molecules in Vesicle-Templated Nanocontainers through Electrostatic Interactions with the Bilayer Scaffold

This work addresses the challenge of creating hollow nanocapsules with a controlled quantity of encapsulated molecules. Such nanocontainers or nanorattle-like structures represent an attractive platform for building functional devices, including nanoreactors and nanosensors. By taking advantage of the electrostatic attraction between oppositely charged cargo molecules and the surface of the templating bilayer of catanionic vesicles, formed by mixing single-tailed cationic and anionic surfactants, we were able to achieve a substantial increase in the local concentration of molecules inside the vesicle-templated nanocapsules. Control of electrostatic interactions through changes in the formulation of catanionic vesicles or the pH of the solution enabled fine tuning of the encapsulation efficiency in capturing ionic solutes. The ability to control the quantity of entrapped molecules greatly expands the application of nanocontainers in the creation of functional nanodevices.