SELECTIVE MOLECULARLY IMPRINTED POLYMERS FOR FLUOROPHOSPHONATE NERVE GASES - PROOF OF PRINCIPLE

. However, these displayed relatively weak binding and limited selectivity. We describe a novel approach for selective molecular recognition and sensing of OP nerve agents containing a P-F bond (e.g., sarin, cyclosarin, soman), envisaged to be superior to the less specific and unstable biological-based field detection for OP exposure based on cholinesterase inhibition. Our MIP design creates selective binding site cavities, complementary to the spatial configuration of the nerve agent (e.g., sarin), and project a strong nucleophile (hydroxamic acid) to the bound OP agent so as to efficiently attack the phosphorous-fluoride bond. This also produces a fluoride ion that can trigger a quantifiable signal 6 . Our approach is illustrated in Figure 1. Four MIPs were synthesized and tested against five OP model compounds, providing the first proof-of-concept for this approach. The incorporation of functional active groups into MIPs provides potential development paths to diverse field detection devices that are based on chemical recognition rather than biological activity. Figure 1. Semorex design for obtaining strategically functionalized MIP binding sites involves polymerization of anhydride functional monomers (methacroyl isopropyl methylphosphonyl anhydride, 1b, for sarin-binding MIP) and treating the resulting highly cross-linked macroporous polymers (control polymers for the corresponding MIP) with hydroxylamine. This reaction releases the phosphonic acid, creating a complementary binding cavity, and also forms the hydroxamate nucleophile. (Conditions: A, 95% cross-linker, solvent (porogen), initiator, heat; B, excess hydroxylamine in methanol) Experimental Instrumentation. A UV Microplate Spectrophotometer (PowerWave XS, Bio-tech) was used to monitor p-nitrophenol optical densities in kinetic