title: Oxidation-responsive OEGylated poly-L-cysteine and solution properties studies.
abstract: The oxidation-responsive behaviors of OEGylated poly-L-cysteine homopolypeptides, that is, poly(L-EG(x)MA-C)n, were investigated. These poly-L-cysteine derivatives adopted mixed conformation in water, in which the β-sheet accounted for a significant proportion. Upon oxidation, the thioethers in polypeptide side chains were converted to polar sulfone groups, which triggered the secondary structure transition from β-sheet preferred conformation to random coil. Accordingly, the increase of side-chain polarity together with conformation changes increased samples' water solubility and cloud point temperature. Using mPEG45-NH2 as macroinitiator, we synthesized PEG45-b-poly(L-EG2MA-C)22 diblock copolymer via ring-opening polymerization (ROP) of L-EG2MA-C N-carboxyanhydride (NCA). The PEG45-b-poly(L-EG2MA-C)22 was able to self-assemble into spherical micelles in aqueous solution, and the micelles could undergo an oxidation-triggered disassembly due to the oxidation-responsive thioethers. Such a new class of oxidation-responsive polypeptides might provide a promising platform to construct inflammation targeting drug delivery systems.
authors: Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.
authors: Xiaohui
authors: X
authors: Fu
authors: Yinan
authors: Y
authors: Ma
authors: Yong
authors: Y
authors: Shen
authors: Wenxin
authors: W
authors: Fu
authors: Zhibo
authors: Z
authors: Li
mesh_terms: D003545:Cysteine / Q000737:chemistry; D016503:Drug Delivery Systems; D006801:Humans; D007249:Inflammation / Q000188:drug therapy*; D008968:Molecular Conformation; D010084:Oxidation-Reduction; D010455:Peptides / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry; D017433:Protein Structure, Secondary; D012996:Solutions / Q000737:chemistry; D013696:Temperature
chemical_list: D010455:Peptides; D011108:Polymers; D012996:Solutions; D011092:Polyethylene Glycols; D003545:Cysteine