Protein polyelectrolytes

All biological systems contain aqueous electrolyte solutions. These solutions consist of strong electrolytes (inorganic salts) as well as various organic substances with acidic or basic functional groups which usually behave as weak electrolytes. The solutions are often gel-like in their consistency because of the polyelectrolytes, proteins, and other macromolecules contained in them. The pH values of biological solutions as a rule are between 6.7 and 7.6. 

Alternate Layer-by-Layer Assembly- Supramolecular Architecture Obtained with Beakers and Tweezers The alternate layer-by-layer assembly technique allows us to prepare molecularly controlled films using very simple and inexpensive techniques. This method is applicable to a wide range of substances, such as polyelectrolytes, proteins and colloidal particles. 

F. Caruso, D.N. Furlong, K. Ariga, I. Ichinose, T. Kimitake, Characterization of Polyelectrolyte-Protein Multilayer Films by Atomic Force Microscopy, Scanning Electron Microscopy, and Fourier Transform Infrared Reflection-Absorption Spectroscopy , Langmuir, 14,4559 (1998)... 

G. Decher, B. Lehr, K. Lowack, Y. Lvov, J. Schmitt, New Nanocomposite Films for Biosensors - Layer-by-Layer Adsorbed Films of Polyelectrolytes, Proteins or DNA , Biosensor Bioelectron., 9, 677 (1994)... 

Influent concentrations and residual concentrations of cationic surfactants, anionic surfactants, cationic polyelectrolyte, anionic polyelectrolyte, proteins, colloids, oxygen, ozone, detergents, suspended sohds, and so on, in the adsorptive bubble separation systems can be determined by the analytical methods reported in the literature (82,127-149). 

The formation of salt bridges in polyelectrolyte/protein complexes is widely accepted. Direct evidences for the release of counterions upon association of the macromolecular partners are however scarcely reported. Potentio-metric studies were found to reveal the ionization or neutralization of proteins in polymer complexes, i.e., a pKa shift of ionizable residues when an association took place [23,25,30], In the presence of neutral polyethylene glycol, pepsin was shown to take up protons from the solution [30], On the contrary, bovine serum albumin released protons from the addition of poly(diallyldimethylammonium chloride) (Figure 5). Despite the simplicity of both the method and the quantitative measurement of a number of ions released per protein, an interpretation in terms of a number of local bridges... 

In [93-95] a combination of turbidimetry and static and dynamic light scattering was applied to study the structure of complexes between PDADMAC samples of different molecular weights and charged mixed micelles. A review on such studies of polyelectrolyte-protein complexes is given in [96]. 

Decher G, Lehr B, Lowack K, Lvov Y, Schmitt J. New nanocomposite films for biosensors—layer-by-layer adsorbed films of polyelectrolytes, proteins or DNA. Biosensors Bioelectronics 1994 9 677-684. 

Multiple Adsorption Cycles of Of sitely Charged Moieties (like Polyelectrolytes, Proteins, and Inorganic Nanoparticles)... 

Lojou, E. Bianco, P. (2004). Buildup of Polyelectrolyte-Protein Multilayer Assembhes... 

FIGURE 14.9. As natural polyelectrolytes, proteins present special problems in that their solution characteristics can change significantly with changes in pH, in the presence of electrolytes, or npon interaction with surfactants, especially charged materials. 

Decher, G., et al. New nanocomposite films for biosensors layer-by-layer adstnbed films of polyelectrolytes, proteins or DNA. Biosens. Bioelectron. 9(9-10), 677-684 (1994)... 

Cooper CL, Dubin PL, Kayitmazer AB et al (2005) Polyelectrolyte-protein complexes. Curr Opin Colloid Interface Sci 10 52-78... 

Gummel J, Boue F, Deme B et al (2006) Charge stoichiometry inside polyelectrolyte-protein complexes a direct SANS measurement for the PSSNa-lysozyme system. J Phys Chem B 110 24837-24846... 

We hope that the topics discussed in this chapter will help readers to understand the properties of solutions of charged polymers and will be useful in future studies of more complicated ionic systems, such as polyelectrolyte gels, polyelectrolyte bmshes, ° polyelectrolyte-protein complexes, ionomers, charged polymers at surfaces and interfaces, and multilayer formation by charged molecules. ... 

A.B. andTurksen, S. (2005) Polyelectrolyte-protein complexes. Current Opinion in Colloid and Interface Science,... 

Upon the addition of polyelectrolyte to a protein solution, an increase in turbidity is observed due to the formation of an insoluble polyelectrolyte/pro-tein complex, followed by precipitation at a specific polyelectrolyte/protein mixing ratio. Such a change in turbidity is often accompanied by an increase in the measured solution conductivity (Fig. 18.3), which is particularly pronounced... 

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