Lite Version|Standard version

To gain access to this content please
Log in via your home Institution.
Log in with your member or subscriber username and password.
Download

Herein, thermo and pH dual-responsive drug-linked pseudo-polypeptide micelles were prepared by a self-assembly strategy. Initially, a temperature-responsive comb-shaped poly(2-isopropyl-2-oxazoline)-b-linear poly(acrylic acid) block copolymer (CPiPrOx-b-PAA) was synthesized through a combination of living cationic ring-opening polymerization and living radical polymerization. Subsequently, conjugation of doxorubicin (DOX) with the linear PAA block through a pH-responsive acylhydrazone bond led to a block copolymer having an amphiphilic characteristic, and this block copolymer then self-assembled into CPiPrOx-b-PAA-DOX micelles. TEM and DLS measurements showed that the CPiPrOx-b-PAA-DOX micelles had a uniform spherical morphology with a solid size of about 50 nm and a hydrodynamic size of about 123 nm. Moreover, the micelle coating of comb-shaped poly(2-isopropyl-2-oxazoline) displayed a temperature-responsive behavior with a phase transition temperature of 45 °C. The CPiPrOx-b-PAA-DOX micelles showed a pH-responsive DOX release in vitro; this confirmed the acid-liable effect of the acylhydrazone bond that linked the linear PAA block with DOX. In in vitro cell test, a dose-dependent cytotoxicity and caveolae-mediated endocytosis of the CPiPrOx-b-PAA-DOX micelles were observed. Based on near-infrared fluorescence (NIRF) imaging, a significant tumor accumulation of the CPiPrOx-b-PAA-DOX micelles was observed when the dye-labeled CPiPrOx-b-PAA-DOX micelles were intravenously injected into H22 tumor-bearing mice.

Graphical abstract: Thermo and pH dual-responsive drug-linked pseudo-polypeptide micelles with a comb-shaped polymer as a micellar exterior

Page: ^ Top