title: Stabilization of lysozyme-incorporated polyion complex micelles by the omega-end derivatization of poly(ethylene glycol)-poly(alpha,beta-aspartic acid) block copolymers with hydrophobic groups.
abstract: To improve the stability of lysozyme-incorporated polyion complex (PIC) micelles in physiological condition, three types of hydrophobic groups, including phenyl (Phe), naphthyl (Nap), and pyrenyl (Py) terminal groups, were separately introduced to the omega-end of poly(ethylene glycol)-poly(alpha,beta-aspartic acid) block copolymers (PEG-P(Asp)). The goal was to enhance association forces between the enzyme, lysozyme, and PEG-P(Asp) carriers. Introduction of these hydrophobic groups significantly decreases micellar critical association concentration and increases the micellar tolerability against increasing NaCl concentrations. Particularly, PIC micelles formed from PEG-P(Asp) with Py groups was most stable against increasing NaCl concentrations up to 0.1 M. Significant deviation from a spherical shape for the micelles was also observed for the PEG-P(Asp)-Py system, consistent with an increased association number.
authors.affiliation: Department of Materials Engineering, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors.forename: Xiaofei
authors.initials: X
authors.lastname: Yuan
authors.forename: Atsushi
authors.initials: A
authors.lastname: Harada
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Yamasaki
authors.forename: Kazunori
authors.initials: K
authors.lastname: Kataoka
mesh_terms: D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D007477:Ions / Q000737:chemistry; D008823:Micelles; D009113:Muramidase / Q000378:metabolism*; D011092:Polyethylene Glycols / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*
chemical_list: D007477:Ions; D008823:Micelles; D011108:Polymers; D001224:Aspartic Acid; D011092:Polyethylene Glycols; D009113:Muramidase