The multilayer nanoparticles formed by layer by layer approach for cancer-targeting therapy.

The multilayer nanoparticles (NPs) were prepared for cancer-targeting therapy using the layer by layer approach. When drug-loaded Pluronic NPs were mixed with vesicles (liposomes) in the aqueous medium, Pluronic NPs were incorporated into the vesicles to form the vesicle NPs. Then, the multilayer NPs were formed by freeze-drying the vesicle NPs in a Pluronic aqueous solution. The morphology and size distribution of the multilayer NPs were observed using a TEM and a particle size analyzer. In order to apply the multilayer NPs as a delivery system for docetaxel (DTX), which is a model anticancer drug, the release pattern of the DTX was observed and the tumor growth was monitored by injecting the multilayer NPs into the tail veins of tumor (squamous cell carcinoma)-bearing mice. The cytotoxicity of free DTX (commercial DTX formulation (Taxotere®)) and the multilayer NPs was evaluated using MTT assay. We also evaluated the tumor targeting ability of the multilayer NPs using magnetic resonance imaging. The multilayer NPs showed excellent tumor targetability and antitumor efficacy in tumor-bearing mice, caused by the enhanced permeation and retention (EPR) effect. These results suggest that the multilayer NPs could be a potential drug delivery system for cancer-targeting therapy.