Development of multisensor systems based on chalcogenide thin film chemical sensors for the simultaneous multicomponent analysis of metal ions in complex solutions

A new type of thin film chemical microsensors based on chalcogenide glass-s ensitive materials was developed by means of silicon planar technology and pulsed laser deposition technique. These miniaturised ion-selective electro des (ISEs) exhibit Nernstian responses over five concentration decades with detection limits of 1 x 10(-7) mol/l towards the primary ions Cu and Pb, a nd 4 x 10(-7) and 3 x 10(-5) mol/l towards Cd and TI, respectively. The thi n film microsensors have been shown to be perspective instruments for the s imultaneous multicomponent analysis of complex liquid media based on the pr inciples of an 'electronic tongue' device. Incorporating the thin film sens ors into a sensor array allowed the multicomponent analysis of heavy metal- ion species (Pb2+, Cd2+, Zn2+ and Fe3+). The concentrations of Pb2+-, Cd2+- and Zn2+-ions can be determined simultaneously by direct potentiometric me asurements using a sensor array of seven all-solid-state thin film chemical microsensors with an accuracy of 15-30%. The sensor array allows overcomin g the problem of an insufficient selectivity of single sensors. The suggest ed microsystem-compatible fabrication technique favours a further miniaturi sation, aimed to a fully integrated electrochemical microsystem. (C) 2001 E lsevier Science Ltd. All rights reserved.