title: Synthesis and evaluation of a star amphiphilic block copolymer from poly(epsilon-caprolactone) and poly(ethylene glycol) as a potential drug delivery carrier.
abstract: A star polymer composed of amphiphilic block copolymer arms has been synthesized and characterized. The core of the star polymer is polyamidoamine (PAMAM) dendrimer, the inner block in the arm is lipophilic poly(epsilon-caprolactone) (PCL), and the outer block in the arm is hydrophilic poly(ethylene glycol) (PEG). The star-PCL polymer was synthesized first by ring-opening polymerization of epsilon-caprolactone with a PAMAM-OH dendrimer as initiator. The PEG polymer was then attached to the PCL terminus by an ester-forming reaction. Characterization with SEC, (1)H NMR, FTIR, TGA, and DSC confirmed the star structure of the polymers. The micelle formation of the star copolymer (star-PCL-PEG) was studied by fluorescence spectroscopy. Hydrophobic dyes and drugs can be encapsulated in the micelles. A loading capacity of up to 22% (w/w) was achieved with etoposide, a hydrophobic anticancer drug. A cytotoxicity assay demonstrated that the star-PCL-PEG copolymer is nontoxic in cell culture. This type of block copolymer can be used as a drug delivery carrier.
authors.affiliation: EIC Laboratories, Inc., 111 Downey Street, Norwood, Massachusetts 02062, USA. feiwang@eiclabs.com
authors.forename: Fei
authors.initials: F
authors.lastname: Wang
authors.forename: Tatiana K
authors.initials: TK
authors.lastname: Bronich
authors.forename: Alexander V
authors.initials: AV
authors.lastname: Kabanov
authors.forename: R David
authors.initials: RD
authors.lastname: Rauh
authors.forename: Jacques
authors.initials: J
authors.lastname: Roovers
mesh_terms: D000818:Animals; D002460:Cell Line; D002470:Cell Survival; D004337:Drug Carriers / Q000737:chemistry*; D005047:Etoposide / Q000008:administration & dosage; D008823:Micelles; D008968:Molecular Conformation; D011091:Polyesters; D011092:Polyethylene Glycols; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry / Q000627:therapeutic use; D013057:Spectrum Analysis; D013501:Surface-Active Agents; D013552:Swine
chemical_list: D004337:Drug Carriers; D008823:Micelles; D011091:Polyesters; D011108:Polymers; D013501:Surface-Active Agents; C016240:polycaprolactone; D011092:Polyethylene Glycols; D005047:Etoposide