Emulsan-based nanoparticles for in vivo drug delivery to tumors.

Nanoparticles have been widely used as drug carriers, and finding new materials for them is important for efficient drug delivery. Herein, we developed a new nanoparticle using emulsan and flax seed oil. Emulsan is one of the representative biosurfactants obtained from Acinetobacter calcoaceticus RAG-1. The resulting nanoparticles have an emulsan shell and a hydrophobic oil core, into which pheophorbide a (Pba) was loaded as a model drug. The nanoparticles were about 165.7 nm and were stably dispersed in an aqueous condition for more than one week. They demonstrated fast uptake in SCC7 mouse squamous cell carcinoma cells and killed the tumor cells after laser irradiation due to the photodynamic effect of Pba. After injection into SCC7 tumor-bearing mice via the tail vein, the particles showed longer blood circulation and 3.04-fold higher tumor accumulation in tissue than free Pba. These results demonstrate that emulsan-based nanoparticles have promising potential in drug delivery.