Tetraphenylsilane-Cored Star-Shaped Polymer Micelles with pH/Redox Dual Response and Active Targeting Function for Drug-Controlled Release

Abstract

This paper presents the design and synthesis of star-shaped copolymers with two poly [2-(diethylamino)ethyl methacrylate] and poly(ethylene glycol) blocks linked via a disulfide bond and each end of the four arms capped by folic acid (FA), from which the prepared nanodrug carriers simultaneously possess pH/redox dual response and active targeting functions. The polymer micelles exhibit excellent stability as reflected by their low critical micelle concentration values of 1.03−2.51 mg/L. The doxorubicin (DOX)-loaded polymer micelles are in the range of 108 to 143 nm, and the DOX-loading capacities are found to be up to 32.3%. The sensitive pH and redox responses are demonstrated by examining the drug release behaviors under the varied acidic condition from pH 7.4 to 5.0 and the glutathione concentrations from 0 to 10 mM, respectively. Moreover, the observation of confocal laser scanning microscopy confirms that the functionalization of arm ends by FA indeed enhances the internalization of DOXloaded micelle particles in HeLa cells. As a result, the DOX-loaded nanocarriers can deliver therapeutic drugs to target HeLa cells, and the viability of HeLa cells (10.1%) approaches the value of the pristine DOX (9.98%), showing promising application as drug delivery nanocarriers for safe and highly efficient cancer therapy.

Confinement Effect on the Surface of a Metal–Organic Polyhedron: Tunable Thermoresponsiveness and Water Permeability

“…No obvious characteristic absorption peak of MG can be observed in the supernatant from PNiPAM–MOP, while large quantities (>70%) of MG remain in that of PNiPAM-IPA, indicating super high absorption and encapsulation capability of PNiPAM–MOPs. This may originate from their star-like configuration and the forced stretched conformation of polymer arms, which expose more secondary amine groups for the binding of MG. , The separated precipitates of PNiPAM–MOP can be redissolved in the separated supernatants when cooled to 4 °C and the encapsulated MG can be fully released to aqueous media. The cycle experiments are repeated for three times, and no obvious decay has been observed in the guest molecule loading and releasing performance of PNiPAM–MOP (Figure c).…”

Angiopep-2-Modified Carboxymethyl Chitosan-Based pH/Reduction Dual-Stimuli-Responsive Nanogels for Enhanced Targeting Glioblastoma

“…9−11 In particular, the cross-linked polymer nanogels have an adjustable and stable internal three-dimensional (3D) network, 12 which is a crucial carrier for anticancer drug delivery. To achieve the trigger release of drugs in tumor areas, some stimulation-sensitive drug delivery systems have been discovered, such as acid pH, glutathione (GSH) concentration, and some enzymes, 13,14 which can effectively achieve intracellular delivery and subcellular release. Chitosan (CS) possesses good biocompatibility, pH-dependent charge reversal characteristics, and low immunogenicity and is widely used in the delivery of anticancer or genetic drugs, biosensing, and tissue engineering.…”

Smart materials for drug delivery and cancer therapy

“…And HPAA was synthesized by polymerization with N,N′‐bis(acryloyl) cystamine and 1‐(2‐aminoethyl) piperazine via Michael addition reaction as hyperbranched GSH responser. In the reporting of Shang et al, four linear GSH‐responsive copolymers were anchored on a tetraphenylsilane core to form a star‐shaped polymer with FA capped at each end of the four arms 105 . The star‐shaped GSH‐responsive polymers were prepared as tumor‐targeting nanodrug carriers.…”