Polyvinylbenzyl Tris-Aminodicarboxylate Microspheres for the Optical Sensing of Cu2+ Ions

Ibrahim Diab Abu-Shqair's picture
Journal Title, Volume, Page: 
American Journal of Analytical Chemistry, 2014, 5, 122-127
Year of Publication: 
2014
Authors: 
Ziad M. Shakhsher
Department of Chemistry and Chemical Technology, Al-Quds University, Jerusalem, Palestine
Current Affiliation: 
Al-Quds University
Ibrahim Abu Shqair
Department of Chemistry, An-Najah National University, Nablus, Palestine
Current Affiliation: 
An-Najah National University
Hanin R. Qasim
Imad Odeh
Department of Chemistry and Chemical Technology, Al-Quds University, Jerusalem, Palestine
Current Affiliation: 
Al-Quds University
Preferred Abstract (Original): 

In this work, a tris(2-aminoethyl)aminodicaboxylate functionality was substituted for the chloride of polyvinyl- benzyl chloride (PVBC) which was lightly cross-linked (2%) with divinyl benzene. The resulting derivatized po- lymer microspheres were embedded in a hydrogel matrix of poly vinyl alcohol cross-linked with glutaraldehyde to produce a sensing membrane. The latter responded selectively to Cu2+ solutions of different concentration ranges (1 × 10−4 M to 1 × 10−6 M). The response is based on the interaction between the metal cations and the negatively charged deprotonated dicarboxylate functional group, which led to neutralization of the charges. As a result, an increase in the turbidity of the sensing membrane occurred which is attributed to a change in the re- fractive index of the derivatized polymer microspheres relative to that of the hydrogel. The change in the turbid- ity of the sensing membrane was measured as absorbance using a conventional spectrophotometer. It was found that Cu2+ ions bind to the aminodicarboxylated-polymer with a formation constant, Kf, of 1 × 105 M−1. SEM, Eds and IR analyses were performed on the aminodicarboxylated microspheres and their Cu2+ complex.