Polymer based lanthanide luminescent sensors for the detection of nerve agents

Several devices are being constructed to measure and detect the nerve agents Sarin and Soman. The devices function by selectively binding the phosphonate hydrolysis products to a luminescent functionality-imprinted copolymer. The copolymers possess a securely bound luminescent lanthanide ion, such as Eu3+, in a coordination complex that has been templated for the chemical functionality resulting from the hydrolysis of Sarin and Soman but has had a weakly bound anion substituted by mass action. The instrumental support for the device is being designed to monitor the change that occurs in the luminescence spectrum of the lanthanide when the analyte is coordinated. The ligand field shifted luminescence of the lanthanide is excited by a compact laser and monitored via optical fiber by either a filter photometer or a monochromator. Miniaturization will be applied to each of the lab bench components to produce a field portable device that will potentially be comparable in size to a pH meter. Initial results using an Ar ion laser excitation source providing 0.3 mW at 465.7 nm yield a limit of detection of 125 ppt. The chemical and spectroscopic selectivity of this device are being combined to reduce the likelihood of false positive analyses.