title: 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-1upon 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-1could 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.
authors: Department of Chemistry, Soongsil University, Seoul 156-743, Korea. nguyenhoangly2007@gmail.com.
authors: Nguyễn Hoàng
authors: NH
authors: Ly
authors: Department of Information Communication, Materials, and Chemistry Convergence Technology, Soongsil University, Seoul 156-743, Korea. chulhun@ssu.ac.kr.
authors: Chulhun
authors: C
authors: Seo
authors: Department of Chemistry, Soongsil University, Seoul 156-743, Korea. sjoo@ssu.ac.kr.|Department of Information Communication, Materials, and Chemistry Convergence Technology, Soongsil University, Seoul 156-743, Korea. sjoo@ssu.ac.kr.
authors: Sang-Woo
authors: SW
authors: Joo
keywords: Cu(II); C≡N stretching mode; Raman spectroscopy; glycine; gold nanoparticles; intracellular imaging