Carboxymethyl chitosan-mediated synthesis of hyaluronic acid-targeted graphene oxide for cancer drug delivery

In order to enhance the efficiency and specificity of anticancer drug delivery and realize intelligently controlled release, a new drug carrier was developed. Graphene oxide (GO) was first modified with carboxymethyl chitosan (CMC), followed by conjugation of hyaluronic acid (HA) and fluorescein isothiocyanate (FI). The resulting GO-CMC-FI-HA conjugate was characterized and used as a carrier to encapsulate the anticancer drug doxorubicin (DOX) to study in vitro release behavior. The drug loading capacity is as high as 95% and the drug release rate under tumor cell microenvironment of pH 5.8 is significantly higher than that under physiological conditions of pH 7.4. Cell uptake studies show that the GO-CMC-FI-HA/DOX complex can specifically target cancer cells, which are over-expressing CD44 receptors and effectively inhibit their growth. The above results suggest that the functionalized graphene-based material has potential applications for targeted delivery and controlled release of anticancer drugs. (C) 2015 Elsevier Ltd. All rights reserved.