Long circulating poly(ethylene glycol)-decorated lipid nanocapsules deliver docetaxel to solid tumors

Purpose. The purpose of this study was to evaluate the ability of poly(ethylene glycol)-coated lipid nanocapsules (LN) to deliver the highly potent hydrophobic anticancer drug docetaxel to solid tumors. Methods. Docetaxel-loaded nanocapsules (80-1.20 nm) were produced by a solvent-free phase inversion process and were coated with polyethylene glycol distearoylphosphatidylethanolamine conjugate by a postinsertion step. In vivo studies were conducted in mice bearing subcutaneously implanted C26 colon adenocarcinoma to assess the pharmacokinetics and biodistribution of both the drug and LN. Results. Incorporation of docetaxel into the LN dramatically increased the drug's biological half-life while providing substantial accumulation at the tumoral site. The pharmacokinetics and biodistribution pattern were found to depend on the specific surface area and shell composition of the nanocapsules. Conclusion. This study demonstrates that docetaxel physically entrapped into a lipid colloidal drug carrier can be efficiently targeted to neoplastic tissues.