Self-assembled polyelectrolyte films

P.A. Neff, A. Naji, C. Ecker, B. Nickel, R. Klitzing, and A.R. Bausch, Electrical detection of self-assembled polyelectrolyte multilayers by a thin film resistor. Macromolecules 39, 463 466 (2006). 

Fendler, J.H. (2003) in Multilayer Thin Films Layer-by-Layer Self-assembled Polyelectrolytes and Nanoplatelets... 

Keywords wrinkling Thin-film Elastomeric polymer Polydimethylsiloxane Patterns Deformation Surfaces Self-assembly Polyelectrolyte multilayer films Thin-films Polymer brushes Colloidal crystallization Mechanical-properties Assembled monolayers Buckling instability Elastomeric polymer Tobacco-mosaic-virus Soft lithography Arrays... 

Figure 29 Self-assembled polyelectrolyte thin film via the technique [341], With permission of Elsevier Science...

ESA technique provided effective surface modification for thin film and separation membrane. ]8/ IBecause the substrate surface contained negatively or positively charged due to the alternate deposition of polycation or polyanion, the transmission of charged particles like ions through self-assembly polyelectrolyte multilayer membrane might be affected by the charged surface. It was also showed that the presence of fixed charges at the surface of the multilayer resulted in Dorman exclusion of multivalent ions as well as the preferential transport of small... 

X. Hu et al.. Fabrication, characterization, and application in SERS of self-assembled polyelectrolyte-gold nanorod multilayered films, Journal of Physical Chemistry B, 109(41), 19385-19389 (2005). 

Ding, B., K. Fujimoto, and S. Shiratori (2005a). Preparation and characterization of self-assembled polyelectrolyte multilayered films on electrospun nanofibers. Thin Solid Films 491(1-2) 23-28. 

Fendler, J., Preparation and utilization of self-assembled ultrathin films composed of polyelectrolytes, nanoparticles and nanoplatelets. Croatica Chim Acta, 1998. 71 p. 1127-1137. 

Meanwhile, a self-assembled alternating multilayer film, composed of a bipolar amphiphile, 4,4 -bis[(12-(trimethylammonio)dodecyl)oxy]azobenzene dibromide 29 and an anionic polyelectrolyte poly(vinyl sulfate, potassium salt) on a pre-coated fused silica substrate, was prepared. The effects of added salt on the photochemical isomerization of the azobenzene unit in the self-assembled multilayer films were investigated. ... 

Amide bond is an effective anchor to connect CNTs to substrate surfaces. Lan et al. [52] covalently assembled shortened multi-walled carbon nanotubes (s-MWNT) on polyelectrolyte films. The shortened MWNT is functionalized with acyl chloride in thionyl chloride (SOCl2) before self-assembling. The FTIR spectrum of self-assem-bled MWNT (SA-MWNT) adsorbed on a CaF2 plate modified with PEI/(PSS/PEI)2 shows two characteristic absorption peaks at 1646cm-1 (amide I bond) and 1524cm-1 (amide II bond) resulting from the amide bond formed between the polyelectrolyte films and s-MWNTs. 

The developed sensor was used for ultrathin-film measurement. The reflection spectrum was shifted during the deposition of thin films (e.g., self-assembly of polyelectrolyte layers) onto the sensor end. The reflection between the thin film and the fiber endface was neglected because of their similar refractive indices. As the film increased its thickness, the length of the fiber cavity changed. The amount of change was estimated by the phase shift of the interferogram. The device could also be used as an immunosensor in which the optical thickness changes were used to... 

Figure 2.25 Dependence of the catalytic current for the oxidation of p-D-glucose mediated by the redox polyelectrolyte film for different number of COx layers self-assembled with (PAH-Os) (COx) (n=m = 2, 4, 6). Taken from [182].

Equations 2.26 and 2.27 carmot be solved analytically except for a series of limiting cases considered by Bartlett and Pratt [147,192]. Since fine control of film thickness and organization can be achieved with LbL self-assembled enzyme polyelectrolyte multilayers, these different cases of the kinetic case-diagram for amperometric enzyme electrodes could be tested [147]. For the enzyme multilayer with entrapped mediator in the mediator-limited kinetics (enzyme-mediator reaction rate-determining step), two kinetic cases deserve consideration in this system in both cases I and II, there is no substrate dependence since the kinetics are mediator limited and the current is potential dependent, since the mediator concentration is potential dependent. Since diffusion is fast as compared to enzyme kinetics, mediator and substrate are both approximately at their bulk concentrations throughout the film in case I. The current is first order in both mediator and enzyme concentration and k, the enzyme reoxidation rate. It increases linearly with film thickness since there is no... 

Decher G, Hong JD, Schmitt J. Buildup of ultrathin multilayer films by a self-assembly process. 3. Consecutively alternating adsorption of anionic and cationic polyelectrolytes on charged surfaces. Thin Solid Films 1992 210 831-835. 

The technique of alternating polyelectrolyte film construction has also been adapted to incorporate semiconductors into layered films. For example, multilayer films have been constructed by alternately dipping a quartz substrate into a solution of poly(diallylmethylammonium chloride) and then a solution of a stabilized CdS or PbS colloid (41). The layer-by-layer self-assembly of alternating polymer and metal sulfide is at least partially driven by the electrostatic attraction of the cationic polymer and the negative charge of the stabilized MC colloid particles. 

Figure 12.5 (a) Layer-by-layer deposition of glucose oxidase and the polyallylamine Os3 +n + -polypyridine polyelectrolyte on the electrode, (b) Typical catalytic current responses for different glucose concentrations obtained by self-assembled nanostructured thin films based on different architectures (i) PAH/Os/GOx, (ii) cysteamine/GOx/PAH-Os, (iii) PAH/GOx/ -Os, and (iv) (PAH-Os)2/(GOx)i. All measurements were performed in 0.1 M tris buffer at pH 7.5. Part (b) Reproduced with permission from Ref. 34a. Copyright Wiley-VCH Verlag GmbH Co. KGaA. 

In another report, layer-by-layer (LbL) self-assembly deposition was employed to prepare the acceptor-sensitizer dyad polyelectrolyte film in DSSC.48 The viologen-containing polymer film with bromide as the counterions... 

Keywords Bioactive Layer-by-layer Multilayered films Polyelectrolyte self-assembly Remote release... 

Fig. 27 Schematic illustration of the LbL self-assembly of a charged poly(phenylacetylene) with induced macromolecular helicity. a An excess of the one-handed helical sense is induced in 30 upon complexation with the optically active (S)-75 in water, b An induced helical 30 can be LbL assembled with an achiral polyelectrolyte having opposite charges (PAH), resulting in multilayer thin films with an induced macromolecular helicity on a substrate...

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