TY - JOUR
T1 - Flow injection analysis system based on amperometric thin-film transducers for free chlorine detection in swimming pool waters
AU - Olivé-Monllau, Rosa
AU - Orozco, Jahir
AU - Fernández-Sánchez, César
AU - Baeza, Mireia
AU - Bartrolí, Jordi
AU - Jimenez-Jorquera, Cecilia
AU - Céspedes, Francisco
PY - 2009/3/15
Y1 - 2009/3/15
N2 - This work reports on the performance of a user-friendly flow injection analysis (FIA) system for the monitoring of free chlorine. A methacrylate flow cell integrating a gold thin-film microelectrode, together with an on-chip gold counter electrode, both fabricated by microfabrication technology, provided robustness, low output impedance, rapid response and low cost to the proposed flow system. An external Ag/AgCl reference electrode placed downstream the chip completes the electrochemical cell. Amperometric detection of chlorine was carried out at a set potential of +350 mV, without oxygen interference. The proposed flow system responded linearly to chlorine concentrations in a range from 0.2 to 5 mg l-1, with a sensitivity of 0.23 μA l mg-1, the estimated limit of detection being 0.02 mg l-1. In addition, the system response was kept stable for at least 10 days (±3σ criterion), by keeping the flow system in an inert atmosphere when not in use. Fifteen samples of swimming pool waters were analyzed and no matrix effects were detected. Also, results were in good agreement with those obtained by a standard method. The excellent analytical performance of the system together with its good working stability would also enable its application for the detection of chlorine in other matrices such as tap water or chlorine stock solutions. © 2008 Elsevier B.V. All rights reserved.
AB - This work reports on the performance of a user-friendly flow injection analysis (FIA) system for the monitoring of free chlorine. A methacrylate flow cell integrating a gold thin-film microelectrode, together with an on-chip gold counter electrode, both fabricated by microfabrication technology, provided robustness, low output impedance, rapid response and low cost to the proposed flow system. An external Ag/AgCl reference electrode placed downstream the chip completes the electrochemical cell. Amperometric detection of chlorine was carried out at a set potential of +350 mV, without oxygen interference. The proposed flow system responded linearly to chlorine concentrations in a range from 0.2 to 5 mg l-1, with a sensitivity of 0.23 μA l mg-1, the estimated limit of detection being 0.02 mg l-1. In addition, the system response was kept stable for at least 10 days (±3σ criterion), by keeping the flow system in an inert atmosphere when not in use. Fifteen samples of swimming pool waters were analyzed and no matrix effects were detected. Also, results were in good agreement with those obtained by a standard method. The excellent analytical performance of the system together with its good working stability would also enable its application for the detection of chlorine in other matrices such as tap water or chlorine stock solutions. © 2008 Elsevier B.V. All rights reserved.
KW - Amperometric detection
KW - FIA system
KW - Free chlorine analysis
KW - Gold miniaturized thin-film transducer
KW - Swimming pool water
U2 - 10.1016/j.talanta.2008.10.015
DO - 10.1016/j.talanta.2008.10.015
M3 - Article
VL - 77
SP - 1739
EP - 1744
JO - Talanta
JF - Talanta
SN - 0039-9140
IS - 5
ER -