Programming pH-responsive release of two payloads from dextran-based nanocapsules

Controlled release of payloads such as drugs or corrosion inhibitors from nanocapsules is a prerequisite for their utilization. Indeed, premature leaching and contamination of the environment can be avoided. Herein, we investigate the pH-dependence of release kinetics of corrosion inhibitors from nanocapsules. Nanocapsules are formed by interfacial crosslinking of dextran derivatives in inverse miniemulsion and subsequently re-dispersed in aqueous solutions. Release kinetics are highly dependent on pH value and can be explained by a complex interplay involving swelling of nanocapsules shell, solubility of corrosion inhibitors, and electrostatic interactions between payloads and the shell.