J. Y. Wang, Y. Z. Wang, Y. X. Li and Y. P. Li
Jilin University, China
Chinese medicine paclitaxel (PTX) is an antitumor drug and can be effective against various types of solid tumors. The clinical applications and the bioavailability of PTX are limited, primarily due to its narrow therapeutic index and very poor solubility in water. So a series of conjugates has been synthesized with the goal of increasing the specificity of PTX toward cancer cells and multifunctional PTX-loaded drug delivery systems are being evaluated. Poly (amidoamine) (PAMAM) is one class of ideal dendrimers because of their unique characteristics such as uniform size distribution, relatively higher transfection efficiency, and lower cytotoxicity (esp. G3-G5) compared to other traditional cationic polymers, when used as drug delivery and probe system. In here, bifunctional therapeutic dendrimer conjugates have been synthesized containing chemotherapeutic PTX and folic acid. We have also demonstrated the applicability of dendrimers as a platform for conjugating Cy5.5 and IONPs forming novel nanoparticles as molecular imaging probes. Therefore, a novel therapeutic delivery system integrating imaging and targeting modalities (FA-PEG-G3.5-PTXCy5.5@ IONPs) has been constructed. Collectively, animal studies suggest that these novel PTX-loaded conjugates have the potential to enhance the effect of fluorescence imaging, MRI contrast and cancer therapy in the course of delivering drugs to target sites.
Keywords: PTX, dual imaging probe, drug delievery.