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Title: Small Angle Neutron Scattering Studies of the Counterion Effects on the Molecular Conformation and Structure of Charged G4 PAMAM Dendrimers in Aqueous Solutions

Abstract

The structural properties of generation 4 (G4) poly(amidoamine) starburst dendrimers (PAMAM) with an ethylenediamine ne (EDA) central core in D O 2 solutions have been studied by small angle neutron scattering. Upon the addition of DCl , SANS patterns show a pronounced inter-particle 2 correlation peaks due to the strong repulsion introduced by the protonation of the amino groups of the dendrimers. By solving the Ornstein-Zernike integral equation (OZ) with hypernetted chain closure (HNC), the dendrimer-dendrimer er structure factor S(Q) is determined and used to fit the experimental data. Quantitative information such as the effective charge per dendrimer and its conformational change at different conditions can be obtained. The results obtained show clear evidence that significant counterion association occurs, strongly mediating the inter-dendrimer interaction. The influence of interplay between counterions and molecular protonation of dendrimers has strong effect on the dendrimer conformation and effective interaction.

Authors:
 [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Spallation Neutron Source (SNS)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
978214
DOE Contract Number:  
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Macromolecules; Journal Volume: 40; Journal Issue: 16
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; AQUEOUS SOLUTIONS; CHAINS; CLOSURES; CONFORMATIONAL CHANGES; EFFECTIVE CHARGE; INTEGRAL EQUATIONS; NEUTRONS; SCATTERING; STRUCTURE FACTORS

Citation Formats

Chen, Wei-Ren. Small Angle Neutron Scattering Studies of the Counterion Effects on the Molecular Conformation and Structure of Charged G4 PAMAM Dendrimers in Aqueous Solutions. United States: N. p., 2007. Web. doi:10.1021/ma0626564.
Chen, Wei-Ren. Small Angle Neutron Scattering Studies of the Counterion Effects on the Molecular Conformation and Structure of Charged G4 PAMAM Dendrimers in Aqueous Solutions. United States. doi:10.1021/ma0626564.
Chen, Wei-Ren. Mon . "Small Angle Neutron Scattering Studies of the Counterion Effects on the Molecular Conformation and Structure of Charged G4 PAMAM Dendrimers in Aqueous Solutions". United States. doi:10.1021/ma0626564.
@article{osti_978214,
title = {Small Angle Neutron Scattering Studies of the Counterion Effects on the Molecular Conformation and Structure of Charged G4 PAMAM Dendrimers in Aqueous Solutions},
author = {Chen, Wei-Ren},
abstractNote = {The structural properties of generation 4 (G4) poly(amidoamine) starburst dendrimers (PAMAM) with an ethylenediamine ne (EDA) central core in D O 2 solutions have been studied by small angle neutron scattering. Upon the addition of DCl , SANS patterns show a pronounced inter-particle 2 correlation peaks due to the strong repulsion introduced by the protonation of the amino groups of the dendrimers. By solving the Ornstein-Zernike integral equation (OZ) with hypernetted chain closure (HNC), the dendrimer-dendrimer er structure factor S(Q) is determined and used to fit the experimental data. Quantitative information such as the effective charge per dendrimer and its conformational change at different conditions can be obtained. The results obtained show clear evidence that significant counterion association occurs, strongly mediating the inter-dendrimer interaction. The influence of interplay between counterions and molecular protonation of dendrimers has strong effect on the dendrimer conformation and effective interaction.},
doi = {10.1021/ma0626564},
journal = {Macromolecules},
number = 16,
volume = 40,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}