Highlights

A novel PEG grafted, furfuryl functionalized copolymer was synthesized by RAFT and consecutive ring opening reactions.

The copolymer was readily grafted on SWCNT by Diels–Alder click reaction in water through an ultrasound-assisted method.

Doxorubicin was loaded in the copolymer grafted SWCNT with a high drug loading capacity.

The drug loaded hybrid showed pH-responsive characteristics and a high antitumor activity towards HeLa cancer cells.

Abstract

This paper reports a green and direct functionalization of poly(ethylene glycol)-graft-[furfuryl-graft-(poly(styrene-alt-maleic anhydride))] (PEG-PSMF) on the surface of single walled carbon nanotubes (SWCNTs) in aqueous media through Diels-Alder (DA) click reaction. Firstly, novel PEG grafted, furfuryl functionalized copolymers were prepared by RAFT polymerization followed by ring opening reactions. The functional copolymer was simply grafted on SWCNTs by DA reaction at room temperature under ultrasonication. The resulting hybrid materials were characterized by ¹H NMR, GPC, UV–vis, FT-IR, TGA, TEM, and DLS. The hybrid materials possessed a high drug loading capacity (DLC) of doxorubicin (DOX), which could reach up to 279.9 wt.% of DLC. Moreover, in vitro drug release profiles showed that drug release rate at pH 5.5 under an acidic condition of tumor cell microenvironment was much higher than at pH 7.4 of the physiological condition. MTT assays demonstrated that the hybrid materials did not have any practical cytotoxicity against the normal HEK293 cell line, while drug loaded hybrids displayed a high antitumor activity towards HeLa cancer cells. This strategy offers a promising SWCNT-based drug carrier for tumor-targeted chemotherapy.