Rapid determination of trace level copper in tea infusion samples by solid contact ion selective electrode

Abstract

A new solid contact copper selective electrode with a poly (vinyl chloride) (PVC) membrane consisting of o-xylylenebis(N,N-diisobutyldithiocarbamate) as ionophore has been prepared. The main novelties of constructed ion selective electrode concept are the enhanced robustness, cheapness, and fastness due to the use of solid contacts. The electrode exhibits a rapid (< 10 seconds) and near-Nernstian response to Cu activity from 10 to 10 mol/L at the pH range of 4.0-6.0. No serious interference from common ions was found. The electrode characterizes by high potential stability, reproducibility, and full repeatability. The electrode was used as an indicator electrode in potentiometric titration of Cu(II) ions with EDTA and for the direct assay of tea infusion samples by means of the calibration graph technique. The results compared favorably with those obtained by the atomic absorption spectroscopy (AAS).

A Screen-Printed Copper Ion Sensor With Photocurable Poly(n-Butyl Acrylate) Membrane Based on Ionophore O-Xylylene Bis(n,n-Diisobutyldithiocarbamate)

“…O-xc compound is a good ionophore as it shows a very good selectivity towards copper ion in copper ion sensors as reported by Kamata et al [14], Woznica et al [15], Birinci et al [16], and Kisiel et al [17]. O-xc is a non-cyclic compound, which consists of dithiocarbamate functional group.…”

“…This sensor showed a Nernstian slope of 29 mV/decade within the linear range from 1.0 × 10 -6 to 1.0 × 10 -1 M, the detection limit of 1.4 × 10 -7 M and good selectivity over a wide variety of interference cations including alkali, alkaline earth, transition, and heavy metal ions. Another copper ion sensor with the same membrane components but used different conductive material, graphite, epoxy, and hardener mixture as the solid contact for the ion selective electrode reported by Birinci et al [16]. The sensor displayed a Nernstian response of 31.3 mV/decade over a linear range, 1.0 × 10 -6 to 1.0 × 10 -1 M, the detection limit of 4.9 × 10 -7 M and selective towards copper ions over common interference cations.…”

“…Acrylate polymer is also photocurable and can be formed by photopolymerization on an electrode surface [28][29]. Compared with PVC membrane deposition method such as solvent casting which needs at least one day of solvent evaporation [16], this photopolymerization method is fast and simple [28]. Moreover, this polymer also has lower glass transition temperature value, T g , enable an excellent adhesion on solid surfaces.…”

“…High sensitivity, low detection limit, and no requirement of large volume of sample also other important advantages using screen-printed electrode [32]. Previously reported copper ion sensors based ionophore o-xc with PVC or pBA membranes are non-screen-printed solid-state sensors [15][16][17]. Therefore, the intention of this study is to explore a screen-printed copper ion sensor based ionophore o-xc with photocurable pBA membrane.…”

A Novel High Selective Colorimetric Chemosensor for Determination of Copper in Food Samples: Visual Detection

“…Because of the direct body adsorption of the elements from food samples, it is essential to determine the level of these heavy metals to investigate their long term effects on the health. [7] Most common techniques for determination of copper is based on the atomic absorption spectroscopy, [8,9] inductive coupled plasma atomic emission spectrometry (ICP-AES), [10] electrochemical methods [11,12] for decreasing the interference effects. Despite the high capability of the atomic methods in selective determination, these techniques are limited due to their destructive procedures and long-time analysis.…”