Dr. Yusa, Shin-ichi
Institution
Department of Materials and Chemistry, University of Hyogo, Himeji, Hyogo, Japan.
Presentation day
Tuesday 1:50 PM
TITLE
Water-soluble polyion complex (PIC) micelles covered with phosphorylcholine and galactose shells
Abstract
Cationic diblock copolymer (L92M81) composed of galactose-bearing poly(2-
lactobionamidoethyl methacrylate) (PMLA) block and cationic poly(methacyloyloxyethyltrimethylammonium
chloride) (PMOETAC) block were prepared via reversible addition-fragmentation chain transfer (RAFT)
radical polymerization. Anionic diblock copolymer (P96A80) composed of biocompatible Poly(2-
methacryloyloxyethylphosphorylcholine) (PMPC) betaine block and anionic poly(2-acrylamido-2-
methylpropanesulfoniate) (AMPS) block was also prepared via RAFT. Stoichiometrically charge neutralized
mixture of these oppositely charged P96A80 and P96A80 was formed water-soluble PIC micelles in phosphate
buffered saline. The PIC micelle was spherical shape with hydrodynamic radius (Rh) of 19.5 nm and zetapotential
of 0 mV confirmed by dynamic and static light scattering, zeta-potential, and TEM measurements.
From 1H NMR relaxation times, the motion of charged blocks (PMOETAC and PAMPS) was restricted in
PIC micelle. The motion of PMLA and PMPC chains was not restricted. Furthermore, form NOESY NMR
measurements PMLA and PMPC chains were close. These observations indicated that PIC micelles were
composed of segregated PIC core and binary shells of PMPC and PMLA. The RCA120 lectin has two
binding sites which can recognize galactose moieties selectively. When RCA120 was added to the PIC
micelle solution, large aggregates formed by interaction between PIC micelle and RCA120 can be observed
as precipitate.
CV
Shin-ichi Yusa is a native of Japan and received B.S. (1993) and M.S. (1995) degrees in polymer chemistry from Osaka University under the direction of Professors Mikiharu Kamachi and Yotaro Morishima. He received a Ph.D. from Osaka University (2000) for a thesis entitled: “Synthesis of Cholesterol Bearing Polymers and Their Self-Assembling Properties.” He joined Himeji Institute of Technology as an assistant professor in 1997. He became associate professor of University of Hyogo (2008). His research interests are in controlled radical polymerization and characterization of water-soluble polymers. He is currently on the editorial board of Polymers (MDPI Publishing), E-Journal of Chemistry (Hindawi Publishing), Open Journal of Polymer Chemistry (Scientific Research Publishing), Dataset Papers in Chemistry (Hindawi Publishing), Academic Editor of International Research Journal of Pure and Applied
Chemistry (Sciencedomain international), and Nanocontainers (Versita).
Literatures
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Nakai, K.; Nishiuchi, M.; Inoue, M.; Ishihara, K.; Sanada, Y.; Sakurai, K.; Yusa, S.-i., Preparation and Characterization of Polyion Complex Micelles with Phosphobetaine Shells. Langmuir 2013, 29 (31), 9651-9661.