Concentrated polymer brush

Size-Exclusion Effect and Protein Repellency of Concentrated Polymer Brushes Prepared by Surface-Initiated Living Radical Polymerization Chiaki Yoshikawa, Atsushi Goto, Norio Ishizuka, Kazuki Nakanishi, Akio Kishida, Yoshinobu Tsujii, Takeshi Fukuda ... 

Size-Exclusion Effect and Protein Repellency of Concentrated Polymer Brushes Prepared by Surface-Initiated Living Radical Polymerization... 

Well-Defined Concentrated Polymer Brushes of Hydrophilic Polymers ... 

Protein Repellency of Concentrate" Polymer Brush Size-... 

Size-Exclusion Effect of the Concentrated Polymer Brush.. 262... 

The use of SAMs and polymer brushes for biological applications is well reviewed in the literature. Hence, this chapter focuses mainly on a "concentrated" polymer brush prepared by surface-initiated living radical polymerization (Sl-LRP) [7]. 

Concentrated Polymer Brush Prepared by SI-LRP 11.2.1 Living Radical Polymerization (LRP)... 

Development of concentrated polymer brush. (Redrawn from Tsujii et al. [7. )... 

Considering the unique structure and properties of the concentrated polymer brush, one of the most attractive applications of this brush is directly toward a biointerface, especially bioinert surface, which prevents biologically important molecules such as protein and cells. 

Suppression of Cell Adhesion on Concentrated Polymer Brushes... 

Many researchers have reported biological applications, i.e., a nonbiofouling surface, with polymer brushes prepared by SI-ATRP [48]. To date, however, few have noted the aforementioned unique structure and properties of concentrated polymer brush obtainable by SI-LRP. 

Concentrated polymer brushes obtainable by SI-LRP prevented proteins and cells compared with the corresponding semidilute brushes, owing to the unique size-exclusion effect (of entropic origin) of the concentrated polymer brushes. This means that the physical structure (possibly including chain dynamics) of graft chains on the surface plays an essential role in bioinertness. 

The research to use concentrated polymer brushes for biointerface application is on the way. We expect to see significant progress in research toward perfect biocompatiblity. 

Yoshikawa, C., Goto, A., Ishizuka, N., Nakanishi, K., Kishida, A., Tsujii, Y, and Fukuda, T. 2007. Size-exclusion effect and protein repellency of concentrated polymer brushes prepared by surface-initiated living radical polymerization. Macromol. Svmv. 248 189. 

Yamago S, Yahata Y, Nakanishi K, Konishi S, Kayahara E, Nomura A, Goto A, Tsujii Y (2013) Synthesis of concentrated polymer brushes via surface-initiated organotellurium-mediated living radical polymerization. Macromolecules 46(17) 6777-6785... 

Nomura A, Okayasu K, Ohno K, Fukuda T, Tsujii Y (2011) Lubrication mechanism of concentrated polymer brushes in solvents effect of solvent quality and thereby swelling state. Macromolecules 44(12) 5013-5019... 

F. 1 Illustration of dilute, seniidilute, and concentrated polymer brushes and the deptaidence of equilibrium thickness (Le) on reduced graft density ([Pg.110]

Goto and coworkers attached a surface-immobilizing initiator IHE onto a siliccm wafer (Scheme 5) and prepared polymer brushes by RTCP [66]. The IHE-immobUized silicon wafer was inunersed in a mixture of MMA, 2-cyanopropyl iodide (a free iodide initiator), azobis(isobutyronitrile) (a radical source), and NIS (a catalyst). The system was purged with an inert gas and heated at 70°C for 4 h to induce polymerization. The and M IM values of the free polymer were 15,000 and 1.31, respectively. From the thickness of the graft polymer and the M of the free polymer, the a value was calculated to be 0.28. This result indicates the successful controlled synthesis of a concentrated polymer brush by RTCP. Another example of the graft polymerization is depicted in Fig. 6,... 

ITP, TERP, and RTCP have successfully been applied to surface-initiated polymerizations of several monomers for preparing well-defined, dilute, semidilute, and concentrated polymer brushes on flat substrates and particles. These LRP techniques are attractive for their robustness, high monomer versatihty, and inducibility by photo-irradiation, for example, and widen the scope of surface-initiated polymerization. Access to a range of macromolecular surface designs could be beneficial for a variety of applications. 

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