Poly(N,N-dimethylacrylamide)-block-Poly(L-lysine) Hybrid Block Copolymers: Synthesis and Aqueous Solution Characterization

✍ Scribed by Aggeliki I. Triftaridou; Frédéric Chécot; Ilias Iliopoulos

• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 472 KB
• Volume: 211
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.200900448

✦ Synopsis

Abstract

Four poly(N,N‐dimethylacrylamide)‐block‐poly(L‐lysine) (PDMAM‐block‐PLL) hybrid diblock copolymers and two PLL homo‐polypeptides are prepared via ROP of ε‐trifluoroacetyl‐L‐lysine N‐carboxyanhydride initiated by primary amino‐terminated PDMAM and n‐hexylamine respectively. The PLL blocks render the copolymers a multi‐responsive behavior in aqueous solution due to their conformational transitions from random coil to α‐helix with increasing pH, and from α‐helix to β‐sheet upon heating. The random coil‐to‐α‐helix transition is found to depend on the PLL length: the longer the peptide segment, the more readily the transition occurred. The same trend was observed for the α‐helix‐to‐β‐sheet transition, which was found to be inhibited for short polypeptides unless conjugated with the PDMAM block.

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