Redox-Responsive Self-Assembly Micelles from Poly(N-acryloylmorpholine-block-2-acryloyloxyethyl ferrocenecarboxylate) Amphiphilic Block Copolymers as Drug Release Carriers

Abstract

Novel well-defined redox-responsive ferrocene-containing amphiphilic block copolymers (PACMO-b-PAEFC) were synthesized by ATRP, with poly(N-acryloylmorpholine) (PACMO) as hydrophilic blocks and poly(2-acryloyloxyethyl ferrocenecarboxylate) (PAEFC) as hydrophobic blocks. The copolymers were characterized by FT-IR and H NMR spectroscopies and gel permeation chromatography, and the crystalline behavior was determined by X-ray diffraction and small-angle X-ray scattering. The results showed that the size of the lamellar crystals and crystallinity vary with the systematic compositions while the periodic structure of the lamellar stacks has no obvious change. These block copolymers could self-assemble and form globular nanoscaled core-shell micellar aggregates in aqueous solution. The reductive ferrocene groups could be changed into hydrophilic ferrocenium via mild oxidation, whereas the polymer micelles at the oxidation state could reversibly recover from their original states upon reduction by vitamin C. The tunable redox response was investigated and verified by transmission electron microscopy, ultraviolet-visible spectroscopy, cyclic voltammetry, and dynamic light scattering measurements. The copolymer micelles were used to entrap anticancer drug paclitaxel (PTX), with high drug encapsulation efficiency of 61.4%, while the PTX-loaded drug formulation exhibited oxidation-controlled drug release, and the release rate could be mediated by the kinds and concentrations of oxidants. MTT assay was performed to disclose the biocompatibility and security of the copolymer micelles and to assess anticancer efficiency of the PTX-loaded nanomicelles. The developed copolymer nanomicelles with reversible redox response are anticipated to have potential in targeted drug delivery systems for cancer therapy.

Novel fluorescein polymer-based nanoparticles: facile and controllable one-pot synthesis, assembly, and immobilization of biomolecules for application in a highly sensitive biosensor

“…There are several drawbacks associated with conventional methods for the preparation of FPNPs, including low polymer yields due to multi-step preparation processes, the poor stability of the hydrophobic uorescein, and uncontrolled immobilization of the biomolecules. 23,33 To address such issues, we attempted the design of novel uorescein polymers via a facile and controllable one-pot synthetic route for application in a highly sensitive biosensor. The chemical structures of the newly designed uorescent copolymers are shown in Fig.…”

Ferrocenyl amphiphilic Janus dendrimers as redox‐responsive micellar carriers

“…[31,49] In pace with the gradual increase of concentration, the JD 9 self-assembles into micelles; meanwhile, the pyrene substrate is located in the hydrophobic micro region of aggregated 9. The spectrophotometry is applied to measure the critical micelle concentration (CMC) of 9 and its self-assembly behavior using hydrophobic pyrene as a fluorescence probe.…”

Responsive polymeric nanoparticles for controlled drug delivery

“…Reactive oxygen species, which are strong oxidizing reagents, are found in a significantly higher concentrations within tumour tissues . Over the last decade, a variety of elements with redox potential across the periodic table have been incorporated into PNPs, with boron, iron, platinum and elements of group VI being the most common. The redox‐responsive group can be located at the block junctions to separate the hydrophilic and hydrophobic parts, followed by PNP degradation and release of cargo .…”