Sensors for detecting humic substances and heavy metal complexes in waters

The interaction between poly(o-ethoxyaniline) (POEA) adsorbed onto solid substrates and humic substances (HS) and Cu/sup 2+/ ions has been investigated with UV-VIS spectroscopy and atomic force microscopy. Both HS and Cu/sup 2+/ cause the POEA film to be further doped, and alter the film morphology. This interaction was exploited in a sensor array made of nanostructured films of POEA, sulfonated lignin and HS, which could detect small concentrations of HS and Cu/sup 2+/ in water.