A Novel pH-sensitive Nanocomposite Based on Graphene Oxide for Improving Doxorubicin Release

A novel nanocarrier for delivering chemotherapeutic drug, Doxorubicin (DOX), was fabricated using Graphene Oxide (GO) as a basic plane for conjugating and assembling other compounds. Previous studies immobilized DOX on the GO sheets with high efficiency however the release was very low and slow due to strong forces between DOX and GO. We attached DOX to GO-poly(ethyleneimine) 2KDa conjugate via a linker containing hydrazide bond. Hydrazide bond is sensitive to acidic pH and a significant increase in the efficiency of DOX release and cytotoxicity was observed in vitro. The MTT assay confirmed advantage of this nanocarrier in comparison to physical loading of DOX on GO sheets. Loading of DOX via hydrazide bond was as low as 4% versus near 75% physical loading of drug. While hydrazide bond containing nanocomposite was 4 to 6 fold more toxic than GO-DOX. The IC50 value for chemically bound DOX to hydrazide containing GO nano-composite was 9.5 µg/ml whereas the IC50 value for GODOX was 39 µg/ml after 72 h. As could be concluded from this study, nanocarriers based on hydrazide bond could be a good candidate for drug delivery.