Imprinted polymer sensors for contamination detection

Molecular imprinting is a useful technique for making a chemically selective binding site. The method involves building a synthetic polymeric scaffold of molecular complements containing the target molecule with subsequent removal of the target to leave a cavity with a structural memory of the target. Molecularly imprinted polymers can be employed as selective adsorbents of specific molecules or molecular functional groups. The imprinted polymers can be fashioned into membranes that can be used to form ion selective electrodes for an imprinted ion. By incorporating molecules or metal ions with useful optical properties in the binding sites of imprinted polymers, spectroscopic sensors for the imprinted molecule may be made. A variety of metal ion selective electrodes and a Pb2+ ion optrode based on imprinted polymers have been fabricated and tested.(1-4) Additionally, a sensor for the hydrolysis product of the nerve agent Soman has been developed using a luminescent lanthanide ion, Eu(III), as optical transducer.(5) Our research continues to explore other means to employ electrochemical and optical transduction.