(545d) Chelator-Doped Conducting Polymer Thin Films for Heavy Metal Ion Detection

Heavy metal ions are major contributors to pollution of the biosphere. Annually, fuel and power industries generate 2.4 million tons of heavy metal waste, while agriculture and waste disposal add another 2 million tons per year. These metals when discharged or transported into the environment may undergo transformations and can have a large environmental, public health, and economic impact. Many of these heavy metals such as arsenic, lead, mercury and cadmium are ranked 1st, 2nd, 3rd and 7th, respectively, on the priority list compiled by the Agency for Toxic Substances and Disease Registry (ATSDR).

Conducting polymer thin films functionalized with different metal-binding chelators, ethylenediaminetetraacetic acid (EDTA), 2(2-pyridylazo)chromotropic acid, and 7,13-diaza-1,4,10-trioxacyclopentadecane (KryptofixTM) were fabricated and studied for their utility in electrochemical detection of heavy metal ions. Chelator. Functionalized thin-films of prypyrrole were generated using electrochemical polymerization with the above cheaters as sole dopants followed by over oxidation. Metals were chelated from the samples on the electrodes by the cheater-functionalized film and then detected using anodic stripping voltammetry. The sensor was applied for rapid, selective and simultaneous analysis of lead, cadmium, and mercury in ppb range.