title: Complex Formation Between Lysozyme and Stabilized Micelles with a Mixed Poly(ethylene oxide)/Poly(acrylic acid) Shell.
abstract: The electrostatic complexation between lysozyme and stabilized polymeric micelles (SPMs) with a poly(acrylic acid) (PAA) or a mixed poly(ethylene oxide)/poly(acrylic acid) (PEO/PAA) shell (SPMs with a mixed shell, SPMMS) and a temperature-responsive poly(propylene oxide) (PPO) core was investigated by means of dynamic, static, and electrophoretic light scattering. The SPMs and different types of SPMMS used resulted from the self-assembly of PAA-PPO-PAA triblock copolymer chains, or PAA-PPO-PAA and PEO-PPO-PEO triblock copolymer chain mixtures (with varying chain lengths and molar ratios) in aqueous solutions at pH 10 and the subsequent cross-linking of their PPO cores via loading and photo-cross-linking of pentaerythritol tetraacrylate (PETA). The solution behavior, structure and properties of the formed complexes at pH 7 and 0.01 M ionic strength, were studied as a function of the protein concentration in the solution (the concentration of the stabilized micelles was kept constant) or equivalently the ratio of the two components. The complexation process and properties of the complexes proved to be dependent on the protein concentration, while of particular interest was the effect of the structure of the shell of the SPMs on the stability/solubility of the complexes. Finally, the fluorescence and mid infrared spectroscopic investigation of the structure of the complexed protein showed that, although a small stretching of the protein molecules occurred in some cases, no protein denaturation takes place upon complexation.
authors.affiliation: Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation , 48 Vassileos Constantinou Avenue, 11635 Athens, Greece.|Institute of Polymers, Bulgarian Academy of Sciences , Akad. G. Bonchev Str., block 103-A, BG-1113 Sofia, Bulgaria.
authors.forename: Maria
authors.initials: M
authors.lastname: Karayianni
authors.affiliation: Institute of Polymers, Bulgarian Academy of Sciences , Akad. G. Bonchev Str., block 103-A, BG-1113 Sofia, Bulgaria.
authors.forename: Valeria
authors.initials: V
authors.lastname: Gancheva
authors.affiliation: Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation , 48 Vassileos Constantinou Avenue, 11635 Athens, Greece.
authors.forename: Stergios
authors.initials: S
authors.lastname: Pispas
authors.affiliation: Institute of Polymers, Bulgarian Academy of Sciences , Akad. G. Bonchev Str., block 103-A, BG-1113 Sofia, Bulgaria.
authors.forename: Petar
authors.initials: P
authors.lastname: Petrov
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008823:Micelles; D046529:Microscopy, Electron, Transmission; D009113:Muramidase / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D000180:Acrylic Resins; D008823:Micelles; D011092:Polyethylene Glycols; C006903:carbopol 940; D009113:Muramidase