Remote stripping electrode for in situ monitoring of labile copper in the marine environment

A remote electrode, operated in the stripping potentiometric mode, is employed for in situ marine surveys of labile copper in bay seawater. The probe relies on a novel electrode assembly, coupled to a long shielded cable, and allows direct immersion of the gold working electrode in seawater. Continuous operation of the probe from a small boat is used for obtaining the distribution pattern of copper in San Diego Bay. Monitoring of labile copper in the unpolluted water of Sequim Bay (Washington state) is also reported. As desired for metal speciation studies, such a submersible in situ operation is performed without perturbation of the natural equilibria. Laboratory optimization, in situ characterization, and future prospects are described and discussed.