Added salts induce micelle-to-vesicle transitions at specific cation concentrations in Hofmeister order by forming polar headgroup–counterion pairs that release water.

The current research involves fabrication of a redox-responsive self-assembly system based on a ferrocene (Fc)-containing β-cyclodextrin (β-CD) derivative (βCD-EG-Fc). βCD-EG-Fc was synthesized, and its redox-sensitive self-assembly behavior was investigated using various techniques. On the basis of the intermolecular host–guest recognition between the β-CD group and the Fc moiety, βCD-EG-Fc primarily formed network-like structures and then vesicles following aging for a specified time. The formation of these structures was primarily driven by hydrogen bonding. Conversely, the oxidized molecules (βCD-EG-Fc⁺) self-assembled into cationic vesicles with the absence of host–guest complexation. Upon controlling the oxidation and reduction of Fc/Fc⁺, reversible aggregate transformation was achieved. The current study resulted in a deeper understanding of β-CD/Fc redox-responsive self-assemblies and contributed to the development of a single-component host–guest inclusion model.

Here we present a pH-responsive self-assembly based on a β-cyclodextrin (β-CD) derivative bearing a dansyl terminus (βCD-C₆–Dns). Vesicular structures were formed over the entire studied pH range (8.5–0.7); however, the molecular configuration and packing within the vesicles were different at different pH values. Intramolecular host–guest complexation occurred mainly between the dansyl group and β-CD at pH values where the dansyl group was not protonated. The alkyl chain also acted as a competitive guest to form host–guest inclusions as confirmed by 2D ¹H NMR measurements. The pH-responsive βCD-C₆–Dns vesicles have potential application prospects in pH-controlled drug release based on the low cytotoxicity of βCD-C₆–Dns.