Poly polyanions

Use the extended 8 —N rule to decide whether the following compounds are polyanionic, poly-cationic or simple ionic. 

Polyelectrolytes may be polyacids, polybases, or polyampholytes. They dissociate into polyions and oppositely charged gegenions. Polyacids release protons on dissociation and become, then, polyanions. Poly(phosphoric acid), I, is an example of a polyacid with a dissociating group in the main chain examples of polyacids with the dissociating group as substituent to the main chain include poly(vinyl phosphonic acid), 11 poly(vinyl sulfuric acid), III poly(vinyl sulfonic acid), IV and poly(vinyl carboxylic acid) = poly-(acrylic acid), V, with the monomeric units... 

Cl quadrupole relaxation studies of Cl binding to synthetic polycations and polyampholytes have recently been started [525] and, furthermore, observations of Cl NMR in polyanion (poly(phosphate) and poly(methacrylic acid)) solutions have been reported [526 527]. In Fig. 10.1 are shown the Cl transverse relaxation rates (from line widths of Fourier transform spectra) for solutions of poly(N,N-dimethyl-aminoethylmethacrylate) and poly(methacrylic acid) as a function of the degree of ionization, a, of the polyelectrolyte [525]. (a = 0 corresponds to equivalent concentrations of acid and polymer and a = 1 to equivalent concentrations of base and polymer.) The Cl interaction with the polycation can be seen to have a considerable effect on the relaxation rate the linear decrease for intermediate a-values reflects the gradual titration of the dimethylammonium groups. Quadrupole relaxation studies seem to be well suited for elucidating halide ion -... 

The behavior of both DNA and polyplexes is also a function of the starting concentration of DNA, which can be in the dilute (polymers act as individual units without intermolecular interactions), intermediate, or semi-dilute regime (polymer chains overlap each other and form a transient network). IPEC studies of the complexation of poly(allylamine hydrochloride) and the two polyanions poly (acrylic acid) and poly(methacrylic acid) have shown that the higher the concentration, the larger and denser are the complexes formed [64]. Unfortunately, this type of study with complexes of DNA and polycations are stiU scarce. 

The formation of vesicles can also be induced by electrostatic interaction or electrostatic self-assembly. Among others, it was shown that LUVs are obtained when a polycation is mixed with a polyanion-fc-poly(ethylene glycol). The vesicle size can be controlled by changing the polymer concentration. Vesicles are also obtained when a polyanion- -poly(ethylene glycol) is mixed with a cationic azobenzene surfactant. In that case, the vesicles are photoresponsive, that is, they dissemble if the azobenzene is isomerized from the irans form to the cis form. Finally, vesicles can also be prepared by mixing a cationic dendrimer and an anionic sulfonate dye. ... 

Sun, J.Q. Wu, T. Liu, F. Wang, Z.Q. Zhang, X. Shen, J.C. (2000). Covalently Attached Multilayer Assembhes by Sequential Adsorption of Polycationic Diazo-Resins and Polyanionic Poly(aayhc add). Langmuir, 16,4620-4624. 

All these results clearly indicate that the BT-HAase activity towards HA can be either enhance or suppress by formation of electrostatic complexes. The BT-HAase activity can be enhance by polycations, which in vivo are mainly proteins, to the condition that (i) they are able, by forming electrostatic complexes with HA, to avoid, or at least to limit, the formation of electrostatic complexes between HA and BT-HAase and, (ii) the ratio of the polycation over HA quantities in the HA-polycation complexes allows enough HA P(l,4) bonds to remain accessible to BT-HAase. Suppression of the BT-HAase activity may result from the formation of two types of electrostatic complexes (i) HA-polycation complexes in which the accessibility of BT-HAase to the HA P(l,4) bonds is hindered because of a too high value of the ratio of the polycation over HA quantities in the complexes and, (ii) polyanion-BT-HAase complexes in which BT-HAase is catalytically inactive. In our study, the only one polyanion was HA and we showed that it is able to form electrostatic complexes with BT-HAase in which BT-HAase is catalytically inactive. Nevertheless, many polyanions, including GAG other than HA (heparin, heparan sulfate, dermatan sulfate), HA derivatives (0-sulfonated HA) and synthetic polyanions (poly(styrene-4-sulfonate)) are known to inhibit HAase (Aronson and Davidson, 1967 Girish and Kemparaju, 2005 Isoyama et al., 2006 Mathews and Dorfman, 1955 Toida et al., 1999). In the case of heparin, Maksimenko et al. (2001) demonstrated that the inhibition results from the formation of electrostatic heparin-HAase complexes. 

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