Polyelectrolyte-cell interactions

Keywords Coacervate Nanoparticles Polyelectrolyte cell interaction Polyelectrolyte complexes Polyelectrolyte drug interaction... 

Richter L, Lavalle P, Vautier D et al (2002) Cell interactions with polyelectrolyte multilayer films. Biomacromolecules 3 1170-1178... 

Exploring Cell Interactions of Dendritic and Protein Polyelectrolytes... 

Hartig SM, Greene RR, Carlesso G et al (2007) Kinetic analysis of nanoparticulate polyelectrolyte complex interactions with endothelial cells. Biomaterials 28 3843-3855... 

Within the PB cell model, the counterion concentration at the outer boundary gives the osmotic pressure, which is a measure of the electrostatic repulsion between neighboring biomolecules. This pressure can also be experimentally determined. " " The Donnan coefficient, on the other hand, is strongly influenced by conditions at the macromolecular surface and can be used to provide key insight into the nature of polyelectrolyte-counterion interaction. " This interaction is important because of the salt-induced conformational changes DNA undergoes. The nature of this behavior is believed to arise from the partial collapse, or condensation. 

To improve and control cell-fiber interactions, the fiber meshes can be either composed of biomacromolecules or postfunctionalized with appropriate biomolecules. The question arises as to which materials can be electrospun. In principle, all polymers can be spun if they provide enough entanglements in solution and adequate interactions between the solvent and solute. Biopolymers, in particular, show dominant H-bonding and/or polyelectrolyte effects, which lead to a strong viscosity increase or poor solvent evaporation. In order to prevent such... 

As already indicated in Sect. 2, the osmotic coefficient 0 provides a sensitive test for the various models describing the electrostatic interaction of the counterions with the rod-like macroion. It is therefore interesting to first compare the PB theory to simulations of the RPM cell model [26, 29] in order to gain a qualitative understanding of the possible failures of the PB theory. In a second step we compare the first experimental values 0 obtained on polyelectrolyte PPP-1 [58] quantitatively to PB theory and simulations [59]. 

The osmotic coefficient obtained experimentally from polyelectrolyte PPP-1 having monovalent counterions compares favorably with the prediction of the PB cell model [58]. The residual differences can be explained only partially by the shortcomings of the PB-theory but must back also to specific interactions between the macroions and the counterions [59]. SAXS and ASAXS applied to PPP-2 demonstrate that the radial distribution n(r) of the cell model provides a sufficiently good description of experimental data. 

At short separation, where both the polyelectrolytes and the ions can distribute more or less freely between the walls, the interaction agrees with that in a symmetric polymer system. With increasing separation the interaction turns back into a repulsion in a symmetric case as the bridging disappears, while in an asymmetric system it remains attractive due to the electrostatic interaction between two oppositely net charged half cells at intermediate separations. In the presence of salt this effect may be strong enough to remain... 

In Chapter 1, we have discussed the potential and charge of hard particles, which colloidal particles play a fundamental role in their interfacial electric phenomena such as electrostatic interaction between them and their motion in an electric field [1 ]. In this chapter, we focus on the case where the particle core is covered by an ion-penetrable surface layer of polyelectrolytes, which we term a surface charge layer (or, simply, a surface layer). Polyelectrolyte-coated particles are often called soft particles [3-16]. It is shown that the Donnan potential plays an important role in determining the potential distribution across a surface charge layer. Soft particles serve as a model for biocolloids such as cells. In such cases, the electrical double layer is formed not only outside but also inside the surface charge layer Figure 4.1 shows schematic representation of ion and potential distributions around a hard surface (Fig. 4.1a) and a soft surface (Fig. 4.1b). 

Here we review the application of ASAXS as applied to the analysis of stiff chain polyelectrolyte in solution. The data discussed here [19] have been obtained using the polyelectrolyte the chemical structure of which is shown in Fig. 1. This system has already been under scrutiny by conventional SAXS some time ago [14]. The paper is organized as follows first we summarize the theory of ASAXS and its application to the problem at hand [18]. Moreover, we will briefly summarize the treatment of rod-like polyelectrolytes within the frame of the Poisson-Boltzmann cell model. An important point for the present analysis is the influence of mutual interaction of the dissolved polyelectrolytes. ASAXS-measurements need to be done at rather higher concentrations so that the interaction of the solute rods may come into play. Here it will be shown that this problem is negligible for the present system. Next possible difficulties encountered in an ASAXS experiment will be discussed and experimental results will be presented. A brief final section will conclude the present discussion. 

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