Chelating electrodes as taste sensor for the trace assessment of metal ions

J. YANEZ HERAS; S.D. RODRIGUEZ; R.M. NEGRI; F. BATTAGLINI

SENSORS AND ACTUATORS B-CHEMICAL

Elsevier

Lugar: Amsterdam; Año: 2010 vol. 145 p. 726 - 733

0925-4005

Impedance spectroscopy combined with principal component analysis allows the trace detection of metalions. The detection system is based on two modified electrodes, each of them containing a chelatingagent (pyrocatechol violet and a nitrilotriacetic derivative); as the chelator is able to capture the metalion at very low concentrations, important electrical changes are produced on the surface environment,generating patterns with different features for each ion. The system is able to differentiate eight metalions (Al3+, Fe3+, Cd2+, Pb2+, Hg2+, Cu2+, Ca2+ and Ag+) at micromolar levels in ultrapure water. The methodallows the detection of metal ions in aqueous samples without the need of sample conditioning, rinsingsteps or the addition of probes. Selecting the appropriate frequencies and sensors, the array can also beapplied to different aqueous systems such as bottled mineral water or concentrated NaCl (27%) yieldingsimilar results.