Patchy Nanocapsules of Poly(vinylferrocene)-Based Block Copolymers for Redox-Responsive Release

Abstract

Nanocapsules composed of a poly(vinylferrocene)-block-poly(methyl methacrylate) shell and a hydrophobic liquid core are prepared in water. The nanocapsule shells display a patchy structure with poly(vinylferrocene) patches with sizes of 25 ± 3 nm surrounded by poly(methyl methacrylate). The functional nanopatches can be selectively oxidized, thereby influencing the colloidal morphology and introducing polar domains in the nanocapsule shell. The hydrophobic to hydrophilic transition in the redox-responsive nanopatches can be advantageously used to release a hydrophobic payload encapsulated in the core by an oxidation reaction.

Polymer‐Modified Mesoporous Silica Thin Films for Redox‐Mediated Selective Membrane Gating

“…While oxidizing the ferrocene moieties (electro)chemically, the polymer chains undergo a remarkable transition from hydrophobic to hydrophilic accompanied by an induction of charge. [ 40,[43][44][45][46] The ferrocene oxidation/reduction cycles could be utilized for controlled release of organics from gels, [ 47 ] for applications as composite colloidal crystal fi lms, [ 46 ] for responsive release of a dye from patchy nanocapsules, [ 48 ] for catalysis modulation, [ 49 ] or for switching surface wettability. [ 50 ] Here, we report the functionalization of an ordered mesoporous silica thin fi lm with redox-responsive poly(2-(methacryloyloxy)ethyl ferrocenecarboxylate) (PFcMA) and end functionalized polyvinylferrocene (PVFc).…”

Smart Nanocontainers: Preparation, Loading/Release Processes and Applications

“…For the release process, the active agents could be released from nanocontainers by external or internal stimuli, which referred to the chemical/physical/biochemical changes within or surrounding of the nanocontainer. For instance, various controlled release methodologies of active agents have been reported, such as desorption controlled release [73], pH-controlled release [1,34,70], temperature-responsive control [22], ion-exchange control [74,75], redox-responsive control of release [76,77], light-responsive controlled-release [78,79] and release under mechanical rapture [80,81].…”

Exploiting Oxidative Microenvironments in the Body as Triggers for Drug Delivery Systems

“…The oxidation of ferrocene gives a stable cation called ferrocenium, leading to a change in polarity (hydrophobic-hydrophilic switch), as the reduced form is not charged. This hydrophobic-hydrophilic transition would either enable sol-gel transition for self-healing properties (138) or enable swellingmediated drug release applications (167) (Table 4). Thus, hostguest inclusion complexes formed by cyclodextrins and ferrocene units are no longer stable after oxidation using chemical reagents (NaOCl) or electrochemical oxidation (Fig.…”