Redox responsive molecular assemblies based on metallic coordination polymers

Abstract

Redox responsive molecular self-assemblies are very important in a wide range of applications including bioengineering, nanotechnology, and medicine. We demonstrate here a redox responsive micellar system based on metal–ligand coordination and electrostatic interaction. The micelles are spontaneously formed in the mixed solutions of a block polyelectrolyte and an oppositely charged iron–bisligand coordination polyelectrolyte, where both Fe²⁺ and Fe³⁺ ions are applicable. Switching between these two oxidation states does not trigger any decomposition of the micelles, but changes the charge composition and the magnetic properties of the system, which enables the uptake of extra, oppositely charged species into the micelles. Moreover, this process triggers spectral and morphological changes of the micelles. These results open a new vista for making redox responsive smart molecular assemblies.