Thermo- and pH-responsive, Lipid-coated, Mesoporous Silica Nanoparticle-based Dual Drug Delivery System To Improve the Antitumor Effect of Hydrophobic Drugs.

Evodiamine (EVO) and Berberine (BBR), from Euodiae Fructus and Coptidis rhizoma, have been used as an herbal medicine pair in traditional Chinese medicine to exert synergistic antitumor effects against various types of tumor cells. However, their clinical use is limited by their poor solubility and adverse toxic side effects. Mesoporous silica nanoparticles (MSNs) possess excellent properties such as a readily functionalized surface, prominent biocompatibility, and huge specific surface area for loading with hydrophobic and hydrophilic drug. On this basis, a novel temperature- and pH-responsive dual drug delivery platform has been developed, in which lipid-coated MSN@p(NIPAM- co-MA) codelivers EVO and BBR. The results indicate that the nanocarrier improves the efficacy and biocompatibility of the drug pair and maintain desirable drug profiles at the low pH and higher temperature of the tumor microenvironment. The dual drug-loaded MSNs showed excellent synergistic therapy effects in vitro (cytotoxicity, cell migration and invasion, angiogenesis) and in vivo (growth of tumor grafts in mice). Meanwhile, the dual drug-loaded nanoparticles showed lower systemic toxicity than either drug alone, the free drug combination, or Taxol. These results suggest that the temperature- and pH-sensitive lipid-coated MSNs are a promising novel carrier for both hydrophobic and hydrophilic drugs.