A novel probe and microsensors for in situ, continuous, automatic profiling of trace elements in natural waters

This paper describes a novel voltammetric in-situ profiling ystem (VIP System) for continuous, real-time monitoring of trace elements in fresh and sea water down to 500 meter depth. The VIP System has been designed using advanced microprocessor and telemetry technology. The heart of the submersible probe is a gel integrated microsensor including either a single or an array microelectrode. The integration of a microelectrode in a gel is a novelty which protects its surface from fouling and allows its application for direct measurements in complex media. Reliability and validity of concentration monitoring obtained using the VIP System have been demonstrated by comparing in-situ and on-field voltammetric data with those obtained using classical techniques. A description of the probe and sensors is given and examples of environmental applications are reported for in-situ trace metal monitoring in oxygen saturated sea water as well as for in-situ profiling of Mn(II) in anoxic lake water