Ionic Liquid-Multiwalled Carbon Nanotubes Nanocomposite Based All Solid State Ion-Selective Electrode for the Determination of Copper in Water Samples

A new copper sensitive all solid-state ion-selective electrode was prepared using multiwalled carbon nanotubes-ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate) nanocomposite as an additional membrane component. The effect of nanocomposite content in the membrane on the electrode parameters was investigated. The study compares, among others, detection limits, sensitivity, and the linearity ranges of calibration curves. Content 6 wt.% was considered optimal for obtaining an electrode with a Nernstian response of 29.8 mV/decade. An electrode with an optimal nanocomposite content in the membrane showed a lower limit of detection, a wider linear range and pH range, as well as better selectivity and potential stability compared to the unmodified electrode. It was successfully applied for copper determination in real water samples.

Anodic Stripping Voltammetric Determination Of Copper In Multivitamin-Mineral Formulations Using Iodine-Coated Platinum Electrode

In this work, the utilization of the modified iodine-coated polycrystalline platinum electrode as a voltammetric sensor for copper determination in pharmaceutical formulations was reported. The optimized experimental parameters for the determination of copper were using 0.1M KCl as a supporting electrolyte with a scan rate of 50 mV/s, deposition potential of - 0.2 V, and a deposition time of 2 minutes. The anodic peak related to Copper oxidation is centered at about + 0.05 V. The extended detected linear range for the developed method was between 1 ppm and 100 ppm. The anodic current showed excellent linearity with R2 = 0.9986. The limit of detection (LOD) and limit of quantitation (LOQ) were 0.115 ppm and 0.346 ppm, respectively, which attests to the sensitivity of the method. The investigation for the effect of potential interferences from multivitamins tablet ingredients indicated a specific selectivity toward copper and the absence of any electrochemical response toward these components. The developed method was successfully applied to analyze copper and the obtained results were in good agreement with the labeled values, besides that, the statistical tests indicated no significant difference at p = 0.05 with 95 % confidence level.

Theoretical Description for Copper (II) Electrochemical Determination and Retention on a 1(2-pyridilazo)-2-naphthole-Modified Anode

A modern and flexible spectrophotometric method for copper determination in food has been proposed to be posted on the electrochemical tracks. The theoretical analysis of the correspondent model confirms the efficiency of the electrochemical reaction for either electroanalytical or electro-synthetical or eliminative processes for copper. As for the oscillatory instability, it will be caused by either chemical or electrochemical influences on the double electric layer.