title: Underpotential deposition-anodic stripping voltammetric detection of copper at gold nanoparticle-modified ultramicroelectrode arrays.
abstract: The sensitive detection of copper (II) at gold nanoparticle-modified ultramicroelectrode arrays (UMEAs) is reported. Gold nanoparticles were electrodeposited onto the UMEAs surface by applying a constant positive potential of 1.6 V for 20 min in a 20-nm gold nanoparticle solution. This process significantly increases the electrode area without losing the UMEAs analytical features. Underpotential deposition-anodic stripping voltammetry of copper (II) with such modified UMEAs was performed and showed a high increase in sensitivity (25.9 +/- 1.3 nC x micro-1) and a broader linear range of response (0-10 microM) compared with those values obtained using bare UMEAs (7.5 +/- 0.6 nC x microM(-1) and 0-2 microM, respectively). The copper content of acid extracts of contaminated soils was successfully determined with the modified UMEAs and results are in good agreement with those obtained using the ICP-AES standard method. Overall, this work shows an alternative easy-to-use novel miniaturized device for the rapid and reliable determination of copper in soil samples whose application could be readily extended to other heavy metals of environmental interest.
authors.affiliation: Instituto de Microelectronica de Barcelona (CNM-IMB), CSIC, Campus UAB, 08193 Bellaterra, Spain. jahir.orozco@cnm.es
authors.forename: Jahir
authors.initials: J
authors.lastname: Orozco
authors.forename: César
authors.initials: C
authors.lastname: Fernández-Sánchez
authors.forename: Cecilia
authors.initials: C
authors.lastname: Jiménez-Jorquera
mesh_terms: D003300:Copper / Q000032:analysis* / Q000737:chemistry; D004563:Electrochemistry / Q000379:methods*; D004784:Environmental Monitoring / Q000295:instrumentation* / Q000379:methods; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D008839:Microelectrodes
chemical_list: D006046:Gold; D003300:Copper