PEG-grafted Hyperbranched Polyethyleneimine-Oxidized Single Walled Carbon Nanotube Complex (PEG-PEI-SWNT) for Sustained Delivery of Doxorubicin

To take advantages of single-walled carbon nanotubes (SWNTs) for cellular delivery of chemotherapeutic agents (e.g. doxorubicin) in order to decrease doxorubicin toxicity and increase its efficacy, we aimed to develop a novel approach to aqueous disperse and stabilize SWNTs through consequent steps of oxidation (oxSWNT) and PEG-PEI complexation (PEG-PEI-SWNT). Doxorubicin was loaded onto the modified SWNTs in alkalione pH with more considerable capacity ( 900 %) than those previously reported, due to complex formation with PEI proved by UV-visible spectroscopy. The loaded carrier was stable in physiologic simulated medium. Drug release was prolonged and dilution independent, but exhibited pH-dependent burst release that makes SWNTs as suitable in vivo drug carriers in acidic tumor milieu.