title: Extending the dynamic range of electrochemical sensors using multiple modified electrodes.
abstract: Multiple electrodes, combined with a chemometric strategy to calibrate the measurement response, have been used for the determination of an analyte across a broader dynamic range than is possible with a single electrode. The model system used for the detection of copper comprised electrodes modified with a self-assembled monolayer. The electrodes were modified with the copper-complexing species (3-mercaptopropionic acid, thioctic acid, and the peptides cysteine and Gly-Gly-His) and copper was determined over concentrations ranging from nanomolar to millimolar using voltammetric analysis. We have demonstrated that by combining the calibration functions from the four electrodes a better estimate (i.e. with smaller variance) of the concentration of the analyte is obtained. Measurement uncertainty is expressed for independently prepared electrodes, which allows the possibility of commercial production and factory calibration. The principles of using multiple electrodes modified with recognition elements with different affinities for the target analyte to extend the dynamic range of sensors is a general one that could be applied to other analytes.
authors.affiliation: School of Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia.
authors.forename: Edith
authors.initials: E
authors.lastname: Chow
authors.forename: Elicia L S
authors.initials: EL
authors.lastname: Wong
authors.forename: Owen
authors.initials: O
authors.lastname: Pascoe
authors.forename: D Brynn
authors.initials: DB
authors.lastname: Hibbert
authors.forename: J Justin
authors.initials: JJ
authors.lastname: Gooding
mesh_terms: D015097:3-Mercaptopropionic Acid / Q000737:chemistry; D000595:Amino Acid Sequence; D003300:Copper / Q000737:chemistry; D003545:Cysteine / Q000737:chemistry; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004566:Electrodes; D006046:Gold / Q000737:chemistry; D008956:Models, Chemical; D010455:Peptides / Q000737:chemistry; D008063:Thioctic Acid / Q000737:chemistry
chemical_list: D010455:Peptides; D008063:Thioctic Acid; D006046:Gold; D003300:Copper; D015097:3-Mercaptopropionic Acid; D003545:Cysteine