Remote biosensor for in-situ monitoring of organophosphate nerve agents

A remote electrochemical biosensor for field monitoring of organophosphate nerve agents is described. The new sensor relies on the coupling of the eff ective biocatalytic action of organophosphorus hydrolase (OPH) with a subme rsible amperometric probe design. This combination results in a fast, sensi tive, selective, and stable response at large sample-instrument distances. Such attractive performance is illustrated for direct measurements of micro molar levels of paraoxon and methyl parathion in untreated river water samp les. Unlike multistep inhibition biosensors, the remote OPH probe offers si ngle-step direct measurements, and is thus highly suitable for the continuo us monitoring task. Variables relevant to field operations are discussed, a long with prospects for remote monitoring and early detection of nerve agen ts.