Multivalent interaction

The adsorption of ions with a strong nonculombic interaction, such as chemical interaction (multivalent metal ions on oxides), leads to so-called specific adsorption. Multivalent ions may adsorb on the one or a few hydroxyl groups, but the number of the occupied adsorption places (groups) does not exceed the valency of the ion, and usually, because of the steric reason is not bigger... 

It should be noted that the conditional constants may also be used for neutralization reactions, red-ox reactions, and precipitation reactions. This treatment provides a rational approach to the interference of specifically interacting (multivalent) ions and ligands on the purely ionic interaction and complexation reactions (e.g., hydrolysis) of interest. It is, however, clear from Equation 8.45 that the disturbing action of ligands and competing metal cations is reduced upon dilution. 

Carbohydrate-protein interactions are usually highly speeifie. As with carbohydrate-carbohydrate interactions, multivalence is essential, beeause multiple interactions between carbohydrates and proteins are necessary to aehieve strong binding or enhanced inhibition. In pursuit of synthetic targets where carbohydrates are multiply displayed over suitable scaffolds, a number of model systems have been used to study multivalent interactions between carbohydrates and proteins.GNPs have also been used in this field, and the results have been reviewed. ... 

A particularly relevant class of biomolecules comprises the so-called glycoproteins or glycopeptides. As with protein-protein (such as RGD-integrin) interactions, the interactions between carbohydrates and proteins facilitate many important biological processes [11, 12). Monovalent carbohydrate-protein interactions show very weak binding affinities (Kj 10 to 10 M) [7], while multivalent interactions frequently enhance the affinity due to the so-called g/y-coside cluster effects [13,14]. In order to study multivalent carbohydrate-protein interactions, multivalent glycoclusters are required. Polymers, dendrimers, benzene scaffolds, monosaccharides, and others can be used as the base to affix multiple carbohydrate units. Chen et al. [15] chose the cyclic decapeptide cyclo-[GPKAKGPKKK] where the Lys 3, 5, 8, and 10 residues were used for functionalization with propiolic acid to yield the tetravalent alkyne 8a, while... 

New factors for tlie establislmient of multilayer stmctures are, for example, tire replacement of tire hydrocarbon chain by a perfluorinated chain and tire use of a subphase containing multivalent ions [29]. The latter can become incoriDorated into an LB film during deposition. The amount depends on tire pH of tire subphase and tire individual ion. The replacement of tire hydrocarbon by a rodlike fluorocarbon chain is one way to increase van der Waals interaction and tlierefore enlrance order and stability in molecular assemblies [431. 

Silica Polymei Metal Ion Interactions in Solution. The reaction of metal ions with polymeric sihcate species in solution may be viewed as an ion-exchange process. Consequently, it might be expected that sihcate species acting as ligands would exhibit a range of reactivities toward cations in solution (59). Sihca gel forms complexes with multivalent metal ions in a manner that indicates a correlation between the ligand properties of the surface Si-OH groups and metal ion hydrolysis (60,61). For Cu +, Fe +, Cd +, and Pb +,... 

Bilayer phase transitions are sensitive to the presence of solutes that interact with lipids, including multivalent cations, lipid-soluble agents, peptides, and proteins. 

Lindhorst TK (2002) Artificial Multivalent Sugar Ligands to Understand and Manipulate Carbohydrate-Protein Interactions. 218 201-235 Lindhorst TK, see Rockendorf N (2001) 217 201-238... 

Xanthine oxidase (XO) is not only an important biological source of ROS but also the enzyme responsible for the formation of uric acid associated with gout leading to painful inflammation in the joints. The XO inhibition effect by the enzymatically synthesized poly(catechin) increased as an increasing concentration of catechin units, while the monomeric catechin showed almost negligible inhibition effect in the same concentration range. ° This markedly amplified XO inhibition activity of poly(catechin) was considered to be due to effective multivalent interaction between XO and the condensed catechin units in the poly (catechin). 

The PL-catechin conjugate showed greatly amplified concentration-dependent inhibition activity against bacterial collagenase (ChC) on the basis of the catechin unit, which is considered to be due to effective multivalent interaction between ChC and the catechin unit in the conjugate. The kinetic study suggests that this conjugate is a mixed-type inhibitor for ChC. Hyaluronidase is an enzyme which catalyzes hydrolysis of hyaluronic acid and is often involved in a number... 

Interactions of pectins with multivalent cations Phase diagrams and structural aspects... 

This is a reasonable inference, because site binding is significant only with multivalent cations and strong electrostatic interactions. Under these conditions ion polarization occurs and bonds have some covalent character (Cotton Wilkinson, 1966). This is illustrated by the data of Gregor, Luttinger Loebl (1955a,b). They measured the complexation constants of poly(acrylic acid), 0 06 n in aqueous solution, with various divalent metals, which, as it so happens, are of interest to AB cements (Table 4.1). The order of stability was found to be... 

Ion binding by reduction of repulsive forces also causes the attractive forces between polyions to increase, and the cement paste thickens. This interaction between polyions may be regarded as a kind of bridge formed by multivalent ions located between the polyions. At this stage the cement paste has the characteristic of a lyophilic sol - high viscosity. 

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