Redox voltammetry of sub-parts per billion levels of Cu2+ at polyaspartate-modified gold electrodes
Data(s) |
01/01/2001
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Resumo |
An electrochemical sensor for the detection of Cu2+ is reported which incorporates poly-l-aspartic acid (PLAsp) with 32–96 aspartate units as a selective ligand for the metal ion. PLAsp is covalently attached to a gold electrode modified with a monolayer of 3-mercaptopropionic acid using carbodiimide coupling via an N-hydroxysuccinimide (NHS) ester intermediate. The acid side groups and deprotonated peptide nitrogens on two aspartate moieties are thought to be primarily responsible for chelation of Cu2+, which remains bound when reduced to Cu+. A consequence of the multiple binding points that are available with a polypeptide is the low detection limit. The lowest concentration detected was 3 nM (0.2 ppb) achieved with Osteryoung square wave voltammetry. This detection limit compares favourably with that of ICP-OES and previously reported cysteine-modified electrodes. Analysis of tap and lake water samples using the PLAsp-modified electrode agreed well with ICP-OES analysis of the same samples.<br /> |
Identificador | |
Idioma(s) |
eng |
Publicador |
Royal Society of Chemistry |
Relação |
http://dro.deakin.edu.au/eserv/DU:30034979/yang-redoxvoltammetry-2001.pdf http://dx.doi.org/10.1039/B102898G |
Direitos |
2001, The Royal Society of Chemistry |
Tipo |
Journal Article |