Surface functionalization of superparamagnetic nanoparticles by an acid-liable polysaccharide-based prodrug for combinatorial monitoring and chemotherapy of hepatocellular carcinoma

For combinatorial monitoring and chemotherapy of hepatocellular carcinoma, the macromolecular prodrug based on hyaluronic acid and doxorubicin hydrochloride was prepared by an acid-labile hydrazone linkage, and then conjugated with amine-modified iron oxide nanoparticles by a carbodiimide mediated coupling reaction. The resultant hybrid nanoparticles have the characteristics of good water dispersibility, superparamagnetic property and high magnetic relaxivity for magnetic resonance imaging. In particular, they demonstrated significant cellular uptake and specific accumulation in human hepatocellular liver carcinoma HepG2 cells due to specific biological recognition of hyaluronic acid. In addition, in vitro cumulative release of doxorubicin hydrochloride from the resultant hybrid nanoparticles was significantly accelerated at a mildly acidic pH of 5.0–6.0 when compared to its release at the physiological pH of 7.4, suggesting the pH-responsive feature of this conjugated prodrug for effective chemotherapy of hepatocellular carcinoma. In vivo antitumor efficacy of the mice further confirmed the effect.