Interpolyelectrolyte interactions

Volodkin D, Schaaf P, Mohwald H et al (2009) Effective embedding of liposomes into polyelectrolyte multilayered films. The relative importance of hpid-polyelectrolyte and interpolyelectrolyte interactions. Soft Matter 5 1394—1405... 

Nowadays, IPECs are typically considered to be self-organizing and ordered macromolecular co-assemblies. This concept is based not only on semi-intuitive understanding of such systems as products of the cooperative interpolyelectrolyte interaction but also on some supporting experimental findings. 

Sukhishvili, S.A., Obol skii, O.L., Astaf eva, I.V., Kabanov, A.V. and Yaroslavov, A.A. (1993) DNA-containing interpolyelectrolyte complexes interaction with liposomes. Polymer Sci. (translatedfrom Vysokomol. Soedin.), 35, 1602-1606. 

Interpolyelectrolyte and lipid-polyelectrolyte interactions play a crucial role in vesicle embedding [84], but the right selection of components can result in a fine structure of liposome-containing films (Fig. 4c, d). The amount of the vesicle-encapsulated material can be varied by a number of vesicle deposition steps ( interlayers ) or by the charge of the liposomes (Fig.4e). The embedding... 

Schwarz S, Dragan S (2004) Nonstoichiometric interpolyelectrolyte complexes as colloidal dispersions based on NaPAMPS and their interaction with colloidal sihca particles. Macromolecular Symposia 210(1) 185... 

By increasing the hydrophobicity of plasmids and reducing their net negative surface charge, PVP may facilitate the uptake of plasmids by muscle cells. Intramuscular injection of PVP-based plasmid formulations in rats significantly increased the number and distribution of expressing cells, as compared to unformulated plasmid. The formation of condensed interpolyelectrolyte complexes between PVP and DNA has been proposed to both protect DNA from nuclease degradation and facilitate its cellular uptake by hydrophobic interaction with cell membranes. The increased hydrophobicity of the complex may enhance interaction with cell membranes and facilitate cell uptake. 

Nanostructures primarily result from polyelectrolyte or interpolyelectrolyte complexes (PEC). The PEC (also referred to as symplex [23]) is formed by the electrostatic interaction of oppositely charged polyelectrolytes (PE) in solution. The formation of PEC is governed by physical and chemical characteristics of the precursors, the environment where they react, and the technique used to introduce the reactants. Thus, the strength and location of ionic sites, polymer chain rigidity and precursor geometries, pH, temperature, solvent type, ionic strength, mixing intensity and other controllable factors will affect the PEC product. Three different types of PEC have been prepared in water [40] (1) soluble PEC (2) colloidal PEC systems, and (3) two-phase systems of supernatant liquid and phase-separated PEC. These three systems are respectively characterized as ... 

Another example of multicompartment micellar IPECs is the macromolec-ular co-assembly of the triblock terpolymer poly(Af,Af-dimethylacrylamide)- /ocfc-poly(A-acryloylalanine)-fetocA -poly(iV-isopropylacrylamide) or the diblock terpolymer poly(A,A-dimethylacrylamide)-fe/(9cA -poly(Ai-isopropylacrylamide)-stat-(A-acryloylvaline), interacting in aqueous media with poly(ar-vinylbenzyl) trimethylammonium chloride (PVBTAC) [76, 77], The authors demonstrated that interpolyelectrolyte complexation of such assemblies formed with PVBTAC within specific pH and temperature ranges makes them stable with respect to the disassembly induced by cooling below critical micellization temperatures. 

The flocculation efficiency of some nonstoichiometric interpolyelectrolyte complex dispersions synthesized by the interaction between poly(sodium 2-acrylamido-2-methylpropanesulfonate) (NaPAMPS) and three strong PCs bearing quaternary ammonium salt centers in the backbone on a stable monodisperse silica dispersion have been tested. The PCs PDADMAC and PCA5 alone showed a very narrow range of flocculation. In the case of the most hydrophobic PC, PCA5D1, the window of optimum flocculation concentration was broader compared with other PCs [88]. 

Buchhammer HM, Petzold G, Lunkwitz K (1999) Salt effect on formation and properties of interpolyelectrolyte complexes and their interactions with silica particles. Langmuir 15 4306... 

A cleavable, temperature-responsive polymeric cross-linker was utilized by Xu and cowoikers [111] to stabilize micelles from PEO-b-PAPMA-b-poly((Af,Af-diisopropylamino)ethyl methacrylate) triblock copolymer. The PNIPAm cross-linker contained activated ester end groups that were reacted with the primary amines on the PAPMA middle block. The trithiocarbonate moiety located at the middle of PNIPAm cross-linker could then be degraded by aminolysis to break the cross-links. Temperature-responsive micelles and vesicles from diblock and triblock copolymers were shell cross-linked via interpolyelectrolyte complexation [108, 112]. The cross-links formed by the electrostatic interactions of oppositely charged polyelectrolytes could be disrupted by the addition of SME. 

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