H. C. Lin, Y. H. Chou and J. Yang, “Development of an Amino Carboxylic Acid-Modified Infrared Chemical Sensor for Selective Determination of Copper Ions in Aqueous Solutions,” Analytica Chimica Acta, Vol. 611, No. 1, 2008, pp. 89-96.
http://dx.doi.org/10.1016/j.aca.2008.01.069

has been cited by the following article:

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

  AUTHORS: Ziad M. Shakhsher, Ibrahim Abu Shqair, Hanin R. Qasim, Imad Odeh

  KEYWORDS: Tris(2-aminoethyl)aminodicarboxylate-Polymer; Optical Sensing; Refractive Index; SEM; Eds

  JOURNAL NAME: American Journal of Analytical Chemistry, Vol.5 No.2, January 27, 2014

  ABSTRACT: 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 polymer 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 refractive index of the derivatized polymer microspheres relative to that of the hydrogel. The change in the turbidity 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.