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dc.contributor.authorGarcés, Josep Lluís
dc.contributor.authorRey Castro, Carlos
dc.contributor.authorDavid, Calin
dc.contributor.authorMadurga, Sergio
dc.contributor.authorMas i Pujadas, Francesc
dc.contributor.authorPastor, Isabel
dc.contributor.authorPuy Llorens, Jaume
dc.date.accessioned2016-11-08T11:17:40Z
dc.date.issued2009
dc.identifier.issn1520-6106
dc.identifier.urihttp://hdl.handle.net/10459.1/58424
dc.description.abstractThe binding of ions or other small molecules to macromolecules and surfaces can be macroscopically characterized by means of the stepwise (or stoichiometric) equilibrium constants, which can be obtained experimentally from coverage versus concentration data. The present work presents a novel, simple, and direct interpretation of the stepwise constants in terms of the microscopic, site-specific, stability constants. This formalism can be applied to the most general case, including the heterogeneity of the sites, interactions among them, multicomponent adsorption, and so forth, and, in particular, to chelate complexation. We show that the stepwise equilibrium constants can be expressed as a product of two factors, (i) the average number of free potential sites (per bound ion) of the microscopic species to be complexed (stoichiometric factor) and (ii) the average of the microscopic stability constants of their free potential sites. The latter factor generalizes the concept of the intrinsic equilibrium constant to systems with chelate complexation and reduces to the standard definition for monodentate binding. However, in the case of heterogeneous multidentate complexation, the stoichiometric factor cannot be known a priori, so that the finding of the intrinsic constants is not trivial. One option is to approximate the stoichiometric factor by the value that would correspond to identical active centers. We investigate the accuracy of this assumption by comparing the resulting approximate intrinsic constants to those obtained by Monte Carlo simulation of several binding models. For the cases investigated, it is found that the assumption is quite accurate when no correlated structures (typical of short-range interactions) are formed along the chain. For adsorption of particles attached to a large number of active centers, the formalism presented here leads to the Widom particle insertion method.ca_ES
dc.description.sponsorshipThe authors gratefully acknowledge support of this research by the Spanish Ministry of Education and Science (Projects CTQ2006-14385 and CTM2006-13583) and by the “Comissionat d’Universitats i Recerca de la Generalitat de Catalunya”.ca_ES
dc.language.isoengca_ES
dc.publisherAmerican Chemical Societyca_ES
dc.relationMIECI/PN2004-2007/CTM2006-13583ca_ES
dc.relationMIECI/PN2004-2007/CTQ2006-14385ca_ES
dc.relation.isformatofReproducció del document publicat a https://doi.org/10.1021/jp9041815ca_ES
dc.relation.ispartofJournal of Physical Chemistry B, 2009, vol. 113, núm 46, p. 15145–15155ca_ES
dc.rights(c) American Chemical Society, 2009ca_ES
dc.titleModel-independent link between the macroscopic and microscopic descriptions of multidentate macromolecular binding: Relationship between stepwise, intrinsic, and microscopic equilibrium constantsca_ES
dc.typearticleca_ES
dc.identifier.idgrec014008
dc.type.versionpublishedVersionca_ES
dc.rights.accessRightsinfo:eu-repo/semantics/restrictedAccessca_ES
dc.identifier.doihttps://doi.org/10.1021/jp9041815
dc.date.embargoEndDate10000-01-01


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