Synthesis of cholic acid-terminated dendritic lysine-block-poly(ethylene glycol)-block-dendritic lysine and its enhanced ability to solubilize Paclitaxel in water

Abstract

Paclitaxel, a chemotherapeutic drug used to inhibit mitosis in cancer cells, requires the use of the solubilizer Cremophor EL due to its poor water solubility. However, Cremophor EL is associated with adverse reactions following chemotherapy. This work reports the synthesis of an alternative solubilizing agent for paclitaxel. Two generations of dendritic lysine were coupled onto both ends of PEG-4000 via reaction of fluorenylmethyloxycarbonyl (FMOC)-lysine-FMOC-OH with dicyclohexylcarbodiimide (DCC)-mediated condensation, and deprotection with 30% piperidine. Cholic acid was attached to the terminal amino groups through the use of DCC/n-hydroxysuccinimide. Synthesis steps were monitored and confirmed by electrospray ionization mass spectroscopy. The results suggest that the synthesized polymer is a viable solubilizing agent for delivery of paclitaxel. Additional studies are required to assess its safety and stability.