Detection of Copper(II) Ions Using Glycine on Hydrazine-Adsorbed Gold Nanoparticles via Raman Spectroscopy

Abstract

A facile, selective, and sensitive detection method for the Cu2+ ions in environmental and biological solutions has been newly developed by observing the unique CN stretching peaks at ~2108 cm−1 upon the dissociative adsorption of glycine (GLY) in hydrazine buffer on gold nanoparticles (AuNPs). The relative abundance of Cu species on AuNPs was identified from X-ray photoelectron spectroscopy analysis. UV-Vis spectra also indicated that the Au particles aggregated to result in the color change owing to the destabilization induced by the GLY-Cu2+ complex. The CN stretching band at ~2108 cm−1 could be observed to indicate the formation of the CN species from GLY on the hydrazine-covered AuNP surfaces. The other ions of Fe3+, Fe2+, Hg2+, Mg2+, Mn2+, Ni2+, Zn2+, Cr3+, Co2+, Cd2+, Pb2+, Ca2+, NH4+, Na+, and K+ at high concentrations of 50 µM did not produce such spectral changes. The detection limit based on the CN band for the determination of the Cu2+ ion could be estimated to be as low as 500 nM in distilled water and 1 µM in river water, respectively. We attempted to apply our method to estimate intracellular ion detection in cancer cells for more practical purposes.

Interaction between Diethyldithiocarbamate and Cu(II) on Gold in Non-Cyanide Wastewater

“…In Figure 4 b, the absorption band was weakened for the cyanide-containing wastewater samples. This interpretation could also be supported by the relatively weak CN intensity at ~2114 cm −1 [ 29 ] of the wastewater after the alkaline chlorination treatment of sample “S2”, as shown in Figure 4 c.…”

“…The detection limit of the current SERS method was found to be around ten times lower than that of the colorimetric test under our experimental conditions. The lowest concentration of our SERS detection of Cu 2+ in wastewater samples was around 1 ppm, which is lower than the Environmental Protection Agency permission level (1.3 ppm = ~20 μM) for drinkable water [ 29 ]. Figure 6 illustrates the alkaline chlorination process of the influent sample “S1” to remove the cyanide species in electroplating the industrial wastewater to produce non-cyanide wastewater “S2”.…”

“…AuNPs were prepared by the previous method [ 28 ]. Our quantification methods for Cu 2+ ions were based on our recent investigation [ 29 ].…”

Modification of egg shell powder with in situ generated copper and cuprous oxide nanoparticles by hydrothermal method*

“…In the present work, the MESP was prepared by hydrothermal method and hence the other possibility is through the protein component route. Collagen protein in egg shell is composed of mainly three amino acids-Glycine, Proline and Hydroxy proline [23]. The hydroxyl proline can react with aqueous copper sulfate solution to undergo reduction of Cu +2 to Cu°to form proline.…”

Method and Electrochemical Biosensor for Detection of Copper in Wine

“…In recent years, several studies have reported on the use of amino acids such as L-cysteine, the glycine-histidine complex for the determination of copper ions based on electrochemical detection [9,10]. Glycine (Gly) is one of the simplest amino acids that can bind copper in a dimeric form [11].…”