Please use this identifier to cite or link to this item: http://repositorio.unicamp.br/jspui/handle/REPOSIP/198795
Type: Artigo de periódico
Title: Dissolved Oxygen Amperometric Sensor Based On Layer-by-layer Assembly Using Host-guest Supramolecular Interactions.
Author: Damos, Flavio S
Luz, Rita C S
Tanaka, Auro A
Kubota, Lauro T
Abstract: The development of a simple, efficient and sensitive sensor for dissolved oxygen is proposed using the host-guest binding of a supramolecular complex at a host surface by combining a self-assembled monolayer (SAM) of mono-(6-deoxy-6-mercapto)-beta-cyclodextrin (betaCDSH), iron (III) tetra-(N-methyl-4-pyridyl)-porphyrin (FeTMPyP) and cyclodextrin-functionalized gold nanoparticles (CDAuNP). The supramolecular modified electrode showed excellent catalytic activity for oxygen reduction. The reduction potential of oxygen was shifted about 200 mV toward less negative values with this modified electrode, presenting a peak current much higher than those observed on a bare gold electrode. Cyclic voltammetry and rotating disk electrode (RDE) experiments indicated that the oxygen reduction reaction involves probably 4-electrons with a rate constant (k(obs)) of 7 x 10(4) mol(-1) Ls(-1). A linear response range from 0.2 up to 6.5 mg L(-1), with a sensitivity of 5.5 microA L mg(-1) (or 77.5 microA cm(-2) L mg(-1)) and a detection limit of 0.02 mg L(-1) was obtained with this sensor. The repeatability of the proposed sensor, evaluated in terms of relative standard deviation was 3.0% for 10 measurements of a solution of 6.5 mg L(-1) oxygen.
Subject: Catalysis
Cyclodextrins
Electrochemical Techniques
Electrodes
Gold
Metal Nanoparticles
Oxygen
Rights: fechado
Identifier DOI: 10.1016/j.aca.2010.02.011
Address: http://www.ncbi.nlm.nih.gov/pubmed/20363396
Date Issue: 2010
Appears in Collections:Artigos e Materiais de Revistas Científicas - Unicamp

Files in This Item:
File SizeFormat 
pmed_20363396.pdf417.26 kBAdobe PDFView/Open


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.