Highly Hydrophilic Polymer Composite Modified Electrode for Trace Copper Detection Based on Synergetic Electrostatic Attractions and Chelating Interactions

Abstract

A new electrochemical sensor for Cu 2 + detection by square wave voltammetry with high sensitivity has been constructed, based on a composite of sodium carboxymethyl cellulose and Nafion. Starting from these two polymers that are rich of hydrophilic groups in backbones, a highly negative-charged composite has been easily prepared, which displays outstanding ability to adsorb and enrich Cu 2 + onto the electrode surface through both electrostatic attractions and chelating interactions. After optimizing test conditions, this new sensor exhibits a good linear signal response to Cu 2 + in a concentration range from 1.0 nΜ to 50.0 nM with a limit of detection of 0.6 nM (S/N = 3), as well as good antiinterference for commonly co-existing metal ions. Besides, this new electrochemical copper sensor has been successfully applied to detect trace Cu 2 + in natural water samples with satisfactory recoveries of 98-104 %. These findings provide a new simple but effective way for the determination of heavy metal ions in environmental pollutants.

Enhanced Long-Term Antifouling Ability and Enrichment Effect of a Vertically Ordered Mesoporous Silica Film via Covalent Linkage of Chondroitin Sulfate for In Situ Detection of Cu2+ in Real Environmental Samples

“…Taken together, these results demonstrated that the VMSF- g -CS/GCE obtains excellent sensing performance to Cu 2+ . The reason is inferred as follows: (1) the synergistic enrichment effects of negative surface charges of VMSF and CS, (2) the complexation effect with Cu 2+ of CS could improve the power of enrichment analysis of Cu 2+ …”

“…After the modification of VMSF, the dissolving peak current of VMSF/GCE significantly increased. It could be due to the enrichment of positively charged molecules and ions from the negative surface of VMSF . When CS was directly modified on the surface of VMSF, the peak currents of Cu 0 at VMSF-CS/GCE were much higher due to the increased active sites and functional groups of CS, which made VMSF-CS to exhibit superior enhancement toward Cu 2+ .…”

“…It could be due to the enrichment of positively charged molecules and ions from the negative surface of VMSF. 54 When CS was directly modified on the surface of VMSF, the peak currents of Cu 0 at VMSF-CS/GCE were much higher due to the increased active sites and functional groups of CS, which made VMSF-CS to exhibit superior enhancement toward Cu 2+ . Compared to the control electrodes, the dissolution peak current toward Cu 2+ was significantly increased by VMSF-g-CS/GCE.…”

“…(1) the synergistic enrichment effects of negative surface charges of VMSF and CS, 54 (2) the complexation effect with Cu 2+ of CS could improve the power of enrichment analysis of Cu 2+ . 41 The electrochemical detection method used in this work is differential pulsed anodic stripping voltammetry, and its process includes electrodeposition and anodic stripping.…”

Zn‐doped NiCo2O4 as Modified Electrode Nanomaterials for Enhanced Electrochemical Detection Performance of Cu(II)

“…Therefore, it is of great significance to detect Cu(II) accurately and quickly. There are many detection methods for Cu(II), chiefly including colorimetric analysis [3], atomic absorption spectrometry (AAS) [4], inductively coupled plasma mass spectrometry (ICP-MS) and electrochemical techniques [5]. Among them, the electrochemical technique for Cu(II) detection of differential pulse anodic stripping voltammetry (DPASV) has been widely utilized because of its enhanced faradic current and decreased non-faradic charging current [6].…”