Synthesis and Characterization of Glycopolymer-Polypeptide Triblock Copolymers
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- 作者：Chang-Ming Dong ; Xue-Long Sun ; Keith M. Faucher ; Robert P. Apkarian ; and Elliot L. Chaikof
- 刊名：Biomacromolecules
- 出版年：2004
- 出版时间：January 2004
- 年：2004
- 卷：5
- 期：1
- 页码：224 - 231
- 全文大小：218K
- 年卷期：v.5,no.1(January 2004)
- ISSN：1526-4602
文摘
Glycopolymer-polypeptide triblock copolymers of the structure, poly(L-alanine)-b-poly(2-acryloyloxyethyl-lactoside)-b-poly(L-alanine) (AGA), have been synthesized by sequential atom transfer radical polymerization(ATRP) and ring-opening polymerization (ROP). Controlled free radical polymerization of 2-O-acryloyl-oxyethoxyl-(2,3,4,6-tetra-O-acetyl-
-D-galactopyranosyl)-(1-4)-2,3,6-tri-O-acetyl--D-glucopyranoside (AEL)by ATRP with a dibromoxylene (DBX)/CuBr/bipy complex system was used to generate a centralglycopolymer block. Telechelic glycopolymers with diamino end groups were obtained by end grouptransformation and subsequently used as macroinitiators for ROP of L-alanine N-carboxyanhydride monomers(Ala-NCA). Gel permeation chromatography (GPC) and nuclear magnetic resonance (NMR) spectroscopyanalysis demonstrated that copolymer molecular weight and composition were controlled by both the molarratios of the Ala-NCA monomer to macroinitiator and monomer conversion and exhibited a narrowdistribution (Mw/Mn = 1.06-1.26). FT-IR spectroscopy of triblock copolymers revealed that the ratio of
-helix/-sheet increased with poly(L-alanine) block length. Of note, transmission electron microscopy (TEM)demonstrated that selected amphiphilic glycopolymer-polypeptide triblock copolymers self-assemble inaqueous solution to form nearly spherical aggregates of several hundreds nanometer in diameter. Significantly,the sequential application of ATRP and ROP techniques provides an effective method for producing triblockcopolymers with a central glycopolymer block and flanking polypeptide blocks of defined architecture,controlled molecular weight, and low polydispersity.
-D-galactopyranosyl)-(1-4)-2,3,6-tri-O-acetyl--D-glucopyranoside (AEL)by ATRP with a dibromoxylene (DBX)/CuBr/bipy complex system was used to generate a centralglycopolymer block. Telechelic glycopolymers with diamino end groups were obtained by end grouptransformation and subsequently used as macroinitiators for ROP of L-alanine N-carboxyanhydride monomers(Ala-NCA). Gel permeation chromatography (GPC) and nuclear magnetic resonance (NMR) spectroscopyanalysis demonstrated that copolymer molecular weight and composition were controlled by both the molarratios of the Ala-NCA monomer to macroinitiator and monomer conversion and exhibited a narrowdistribution (Mw/Mn = 1.06-1.26). FT-IR spectroscopy of triblock copolymers revealed that the ratio of-helix/-sheet increased with poly(L-alanine) block length. Of note, transmission electron microscopy (TEM)demonstrated that selected amphiphilic glycopolymer-polypeptide triblock copolymers self-assemble inaqueous solution to form nearly spherical aggregates of several hundreds nanometer in diameter. Significantly,the sequential application of ATRP and ROP techniques provides an effective method for producing triblockcopolymers with a central glycopolymer block and flanking polypeptide blocks of defined architecture,controlled molecular weight, and low polydispersity.