Field-deployable amperometric enzyme electrodes for direct monitoring of organophosphate nerve agents

Amperometric enzyme electrodes for field, on-site and in-situ/on-line remote, monitoring of organophosphate nerve agents is reported. The sensors rely upon the coupling of the rapid biocatalytic hydrolysis of the organophosphates by the immobilized organophosphorus hydrolase and the sensitive and rapid anodic detection of p-nitrophenol product. The biosensors are fast responding, highly selective and show sub-micromolar lower detection limit for paraoxon and methyl parathion. The low detection limits coupled with high selectivity and faster and simplified operation are the benefits of the developed biosensors over the analogous enzyme inhibition biosensors make them ideal for field monitoring of organophosphate compounds.