An injectable thermo-responsive hydrogel based cellulose-brush derivative for the sustained release of doxorubicin

摘要

A cellulose-grafted-poly(N-isopropylacrylamide) (cellulose-g-PNIPAAm) copolymer with thermo-responsivity was synthesized using homogeneous activators regenerated by electron transfer for atom transfer radical polymerization (ARGET-ATRP). The prepared copolymer dispersed at low concentration in water or phosphate-buffered saline (PBS) at 25 degrees C could self-assembly into micelles at 37 degrees C. The size and morphology of these micelles were determined by dynamic light scattering and transmission electron microscopy. The copolymer at a concentration over 4.2% by weight in water formed an injectable thermo-responsive hydrogel that was composed of micelles when the temperature increased to 37 degrees C. This hydrogel was used to load the anticancer drug doxorubicin (DOX). In vitro release studies demonstrated that this hydrogel released DOX in a sustained manner. Furthermore, this cellulose-based injectable thermo-responsive hydrogel was used in cytotoxicity tests, revealing that it was very biocompatible. Based on the above results, this cellulose-g-PNIPAAm injectable thermo-responsive hydrogel has strong potential for application in smart drug delivery systems.