Mixed Polyplex Micelles with Thermoresponsive and Lysine-Based Zwitterionic Shells Derived from Two Poly(vinyl amine)-Based Block Copolymers

• DOI: 10.1021/acs.langmuir.0c02197
• Publication Date: 2021-03-02T12:39:24Z
• Authors: Ryosuke Kanto; Ryo Yonenuma; Mizuki Yamamoto; Hiroyuki Furusawa; Shigekazu Yano; Mitsuru Haruki; Hideharu Mori
• Keywords: Cationic polymerization; Zeta potential; Electrophoretic light scattering; Chain transfer

Two series of poly(vinyl amine) (PVAm)-based block copolymers with zwitterionic and thermoresponsive segments were synthesized by the reversible addition–fragmentation chain transfer polymerization. A mixture two copolymers, poly(N-acryloyl-l-lysine) (PALysOH) poly(N-isopropylacrylamide) (PNIPAM), which have same cationic PVAm but different shell-forming segments, used to prepare mixed polyplex micelles DNA. Both PVAm-b-PALysOH PVAm-b-PNIPAM showed low cytotoxicity, characteristic assembled structures stimuli-responsive properties. The segment in both site-specific interactions DNA, evaluated dynamic light scattering, zeta potential, circular dichroism, agarose gel electrophoresis, atomic force microscopy, transmission electron microscopy measurements. PVAm-b-PNIPAM/DNA polyplexes temperature-induced formation size, surface charge, chiroptical property polymer-DNA binding governed nitrogen/phosphate (N/P) ratio. DNA strength colloidal stability PVAm-b-PALysOH/DNA could be tuned introducing an appropriate amount PALysOH functionality, while maintaining property, regardless N/P originating from hydrophobic (dehydrated) PNIPAM chains upon heating, remarkable under salty conditions owing presence on surface.