An optical characterization of Tris(2-aminoethyl)aminocarboxylic acid Functionalized Polyvinylbenzyl Chloride Microspheres using polymer swelling
Loading...
Date
2011-06-01
Authors
Ziad M. Shakhsher
Ibrahim Abu Shqair
Hanin R. Qasim
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
<p>In this work, Tris(2-aminoethyl)aminocaboxylate functional group was attached chemically to the backbone of polyvinylbenzyl chloride which was lightly cross-linked with divinyl benzene.This ligand has a chemical structure similar to that of ethylenediamine tetraacetic acid (EDTA), as a common chelating agent for metal ions. These derivatized polymer microspheres were embedded in a hydrogel matrix of poly vinyl alcohol cross-linked with glutaraldehyde, which is optically characterized. The response is based on the interaction between the metal cations with the negative charges of the deprotonated carboxylate functional group, which led to neutralization of the charges and thus to polymer shrinking. As a result, an increase in the turbidity of the sensing membrane due to a change in the refractive index between the hydrogel and the derivatized polymer microspheres occurred. The changes in the turbidity of the sensing membrane were measured as absorbance using a conventional spectrophotometer. This sensing membrane responded selectively to Cu2+ solutions of different concentrations range (1x106-M to 1x104- M). It is found that Cu2+ bind to the demonstrated functionalized-polymer with formation constant of 1 x 105 M-1.</p>
<p>In this work, Tris(2-aminoethyl)aminocaboxylate functional group was attached chemically to the backbone of polyvinylbenzyl chloride which was lightly cross-linked with divinyl benzene.This ligand has a chemical structure similar to that of ethylenediamine tetraacetic acid (EDTA), as a common chelating agent for metal ions. These derivatized polymer microspheres were embedded in a hydrogel matrix of poly vinyl alcohol cross-linked with glutaraldehyde, which is optically characterized. The response is based on the interaction between the metal cations with the negative charges of the deprotonated carboxylate functional group, which led to neutralization of the charges and thus to polymer shrinking. As a result, an increase in the turbidity of the sensing membrane due to a change in the refractive index between the hydrogel and the derivatized polymer microspheres occurred. The changes in the turbidity of the sensing membrane were measured as absorbance using a conventional spectrophotometer. This sensing membrane responded selectively to Cu2+ solutions of different concentrations range (1x106-M to 1x104- M). It is found that Cu2+ bind to the demonstrated functionalized-polymer with formation constant of 1 x 105 M-1.</p>
<p>In this work, Tris(2-aminoethyl)aminocaboxylate functional group was attached chemically to the backbone of polyvinylbenzyl chloride which was lightly cross-linked with divinyl benzene.This ligand has a chemical structure similar to that of ethylenediamine tetraacetic acid (EDTA), as a common chelating agent for metal ions. These derivatized polymer microspheres were embedded in a hydrogel matrix of poly vinyl alcohol cross-linked with glutaraldehyde, which is optically characterized. The response is based on the interaction between the metal cations with the negative charges of the deprotonated carboxylate functional group, which led to neutralization of the charges and thus to polymer shrinking. As a result, an increase in the turbidity of the sensing membrane due to a change in the refractive index between the hydrogel and the derivatized polymer microspheres occurred. The changes in the turbidity of the sensing membrane were measured as absorbance using a conventional spectrophotometer. This sensing membrane responded selectively to Cu2+ solutions of different concentrations range (1x106-M to 1x104- M). It is found that Cu2+ bind to the demonstrated functionalized-polymer with formation constant of 1 x 105 M-1.</p>