Polymeric nanospheres fabricated with natural emulsifiers for clinical administration of an anticancer drug paclitaxel (Taxol^®)

Paclitaxel (Taxol^®) is one of the most effective anticancer drugs found from nature in recent decades, which can treat various cancers including ovarian, breast, brain, colon and lung cancer, and AIDS-related cancer. Due to its low aqueous solubility, adjuvants such as Cremophor EL, which causes serious side effects, have to be used in its administration. Our aim is to develop an alternative delivery system to achieve better therapeutic effects with minimum side effects. Paclitaxel-loaded nanospheres of biodegradable polymers were prepared by an improved solvent extraction/evaporation technique. Phospholipids, cholesterol and vitamins were used to replace traditional chemical emulsifiers to achieve high encapsulation efficiency (EE) and desired release rate of the drug. Nanospheres prepared under various conditions are characterized by the light scattering for size and size distribution, the scanning electron microscopy (SEM) and the atomic force microscopy (AFM) for surface morphology; differential scanning calorimetry (DSC) for the physical status of the drug within the polymeric matrix; the zeta-potential measurement for the surface charge properties; and X-ray photoelectron spectroscopy (XPS) for the surface chemistry. In-vitro release kinetics were measured by high-performance liquid chromatography (HPLC). Best design was pursued to develop a product for cancer chemotherapy.