Synthesis and Characterization of Star-Shaped Block Copolymer sPCL-b-PEG-GA. (26th April 2014)

• Record Type: Journal Article
• Authors: Zhang, Yi; Zhao, Qian; Shao, Hewei; Zhang, Shiyu; Han, Xiaoyan
• Other Names: Kyzas George Z. Academic Editor.
• Is Part Of: Advances in materials science and engineering. Volume 2014(2014)
• Publication Date: 2014-04-26
• Subjects: Materials science -- Periodicals; Materials science; Periodicals; 620.11
• DOI: 10.1155/2014/107375
• Languages: English
• ISSNs: 1687-8434

Abstract

Abstract : Compared to linear polymers with the same molecular weight, star-shaped polymers have the superiority of drug loading and delivery. The glycyrrhetinic acid (GA) from licorice is remarkably characteristic of liver distribution and liver cells targetability. In this paper, four-armed star-shaped polycaprolactone was synthesized and amino polyethylene glycol was modified by glycyrrhetinic acid (NH2 -PEG-GA). Then the condensation reaction between the two above polymers finally produced four-armed star-shaped poly(ethylene glycol)-b-poly( ε -caprolactone) block copolymer (sPCL-b-PEG-GA). The structures of the intermediates and product were characterized by 1 H NMR. The results indicated that the structure and molecular weight of sPCL-b-PEG-GA can be controlled by the varied ratios of pentaerythritol (PTOL) to ε -caprolactone ( ε -CL) in the presence of stannous octoate (Sn(Oct)2 ), and the amphiphilic copolymer sPCL-b-PEG-GA consists of PTOL as core, PCL as inner hydrophobic segments, PEG as external hydrophilic segments, and terminal glycyrrhetic acid as targeting ligand. The work explored a new synthesis route of star poly(ethylene glycol)-b-poly( ε -caprolactone) copolymer with liver targetability. The star-shaped polymer is expected to be an efficient drug carrier.