Using EPR To Compare PEG-branch-nitroxide "Bivalent-Brush Polymers" and Traditional PEG Bottle-Brush Polymers: Branching Makes a Difference

被引：51

作者：

Burts, Alan O. ^{[1
]}

Li, Yongjun ^{[2
]}

Zhukhovitskiy, Aleksandr V. ^{[1
]}

Patel, Paresma R. ^{[3
]}

Grubbs, Robert H. ^{[3
]}

Ottaviani, M. Francesca ^{[4
]}

Turro, Nicholas J. ^{[2
]}

Johnson, Jeremiah A. ^{[1
]}

机构：

[1] MIT, Dept Chem, Cambridge, MA 02139 USA

[2] Columbia Univ, Dept Chem, New York, NY 10027 USA

[3] CALTECH, Div Chem & Chem Engn, Pasadena, CA 91125 USA

[4] Univ Urbino, Dept Earth Life & Environm Sci, I-61029 Urbino, Italy

来源：

MACROMOLECULES | 2012年 / 45卷 / 20期

基金：

美国国家科学基金会;

关键词：

DNA-TEMPLATED POLYMERIZATION; STARBURST DENDRIMERS; RADICAL COPOLYMERIZATION; MULTIGRAFT COPOLYMERS; AMPHIPHILIC POLYMER; CONTINUOUS-WAVE; CHAIN-LENGTH; SEQUENCE; ARCHITECTURE; CENTIPEDES;

D O I：

10.1021/ma301874d

中图分类号：

O63 [高分子化学（高聚物）];

学科分类号：

070305 ; 080501 ; 081704 ;

摘要：

Attachment of poly(ethylene glycol) (PEG) to polymeric nanostructures is a general strategy for sterically shielding and imparting water solubility to hydrophobic payloads. In this report, we describe direct graft-through polymerization of branched, multifunctional macromonomers that possess a PEG domain and a hydrophobic nitroxide domain. Electron paramagnetic resonance (EPR) spectroscopy was used to characterize microenvironments within these novel nanostructures. Comparisons were made to nitroxide-labeled, traditional bottle-brush random and block copolymers. Our results demonstrate that bivalent bottle-brush polymers have greater microstructural homogeneity compared to random copolymers of similar composition. Furthermore, we found that compared to a traditional brush polymer, the branched-brush, "pseudo-alternating" microstructure provided more rotational freedom to core-bound nitroxides, and greater steric shielding from external reagents. The results will impact further development of multivalent bottle-brush materials as nanoscaffolds for biological applications.

引用

页码：8310 / 8318

页数：9

共 71 条

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