Molecularly imprinted polymer-based potentiometric sensor for degradation product of chemical warfare agents. Part I. Methylphosphonic acid.

A biomimetic potentiometric sensor for the specific recognition of methylphosphonic acid (MPA), the degradation product of nerve agents sarin, soman, VX, etc., was designed. This involves the preparation of MPA imprinted polymer particles and removal of the template by soxhlet extraction. Subsequently, the leached MIP particles were dispersed in 2-nitrophenyloctyl ether (plasticizer) and embedded in polyvinyl chloride matrix. The sensor responds to MPA in the concentration range 5x10(-8) to 1x10(-4) and 1x10(-3) to 1x10(-1)M with a detection limit of 5x10(-8)M. The selectivity of the sensor has been tested with respect to chemical analogues such as phosphoric acid, sodium dihydrogen phosphate, organophosphorous pesticide and triazine herbicides. The utility of the sensor was tested for field monitoring of MPA in spiked ground water.