Dual functionalized telechelic block copolymers with reproducible block sizes prepared by microwave assisted RAFT polymerization

End-functionalized polymers by controlled/living radical polymerizations: synthesis and applications

This review focuses on end-functionalized polymers synthesized by controlled/living radical polymerizations and the applications in fields including bioconjugate formation, surface modification, topology construction, and self-assembly.

Tumour-targeting photosensitisers for one- and two-photon activated photodynamic therapy

Efficient receptor-mediated delivery of a folate-targeted photosensitiser to kill cancer cells following two-photon excitation in the near-infrared is demonstrated.

Reversible Self-Assembly of Backbone-Thermoresponsive Long Chain Hyperbranched Poly(N-Isopropyl Acrylamide)

In this paper, we mainly described the reversible self-assembly of a backbone-thermoresponsive, long-chain, hyperbranched poly(N-isopropyl acrylamide) (LCHBPNIPAM) in aqueous solution. Here, we revealed a reversible self-assembly behavior of LCHBPNIPAM aqueous solution derived from temperature. By controlling the temperature of LCHBPNIPAM aqueous solution, we tune the morphology of the LCHBPNIPAM self-assemblies. When the solution temperature increased from the room temperature to the lower critical solution temperature of PNIPAM segments, LCHBPNIPAM self-assembled from multi-compartment vesicles into solid micelles. The morphology of LCHBPNIPAM self-assemblies changed from solid micelles to multi-compartment vesicles again when the temperature decreased back to the room temperature. The size presented, at first, an increase, and then a decrease, tendency in the heating-cooling process. The above thermally-triggered self-assembly behavior of LCHBPNIPAM aqueous solution was investigated by dynamic/static light scattering, transmission electron microscopy, atomic force microscopy, fluorescence spectroscopy, ¹H nuclear magnetic resonance in D₂O, and attenuated total reflectance Fourier transform infrared spectroscopy. These results indicated that LCHBPNIPAM aqueous solution presents a reversible self-assembly process. The controlled release behaviors of doxorubicin from the vesicles and micelles formed by LCHBPNIPAM further proved the feasibility of these self-assemblies as the stimulus-responsive drug delivery system.

Folate Receptor-Targeted Polymeric Micellar Nanocarriers for Delivery of Orlistat as a Repurposed Drug against Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is a recalcitrant malignancy with no available targeted therapy. Off-target effects and poor bioavailability of the FDA-approved antiobesity drug orlistat hinder its clinical translation as a repurposed new drug against TNBC. Here, we demonstrate a newly engineered drug formulation for packaging orlistat tailored to TNBC treatment. We synthesized TNBC-specific folate receptor-targeted micellar nanoparticles (NP) carrying orlistat, which improved the solubility (70-80 μg/mL) of this water-insoluble drug. The targeted NPs also improved the delivery and bioavailability of orlistat to MDA-MB-231 cells in culture and to tumor xenografts in a nude mouse model. We prepared HEA-EHA copolymer micellar NPs by copolymerization of 2-hydroxyethylacrylate (HEA) and 2-ethylhexylacrylate (EHA), and functionalized them with folic acid and an imaging dye. Fluorescence-activated cell sorting (FACS) analysis of TNBC cells indicated a dose-dependent increase in apoptotic populations in cells treated with free orlistat, orlistat NPs, and folate-receptor-targeted Fol-HEA-EHA-orlistat NPs in which Fol-HEA-EHA-orlistat NPs showed significantly higher cytotoxicity than free orlistat. In vitro analysis data demonstrated significant apoptosis at nanomolar concentrations in cells activated through caspase-3 and PARP inhibition. In vivo analysis demonstrated significant antitumor effects in living mice after targeted treatment of tumors, and confirmed by fluorescence imaging. Moreover, folate receptor-targeted Fol-DyLight747-orlistat NP-treated mice exhibited significantly higher reduction in tumor volume compared to control group. Taken together, these results indicate that orlistat packaged in HEA-b-EHA micellar NPs is a highly promising new drug formulation for TNBC therapy. Mol Cancer Ther; 15(2); 221-31. ©2015 AACR.