Asa D. Vaughan and Mark E. Byrne. Biomimetic & Biohybrid Materials, Biomedical Devices, and Drug Delivery Laboratories, Department of Chemical Engineering, Auburn University, Auburn, AL 36849-5127
Imprinted polymer networks with intrinsic binding properties are materials that have a particular “trained” affinity for a specific target molecule. The “trained” macromolecular memory within these polymer networks are due to two synergistic effects: (i) shape specific cavities that match the template molecule, which provide stabilization of the chemistry in a crosslinked matrix, and (ii) chemical groups oriented to form multiple non-covalent complexation points with the template. Kinetics analysis of the polymerization reaction show increases in the chemical controlled polymerization mechanism with the use of “living” polymerization techniques. Binding parameter analysis in conjunction with kinetic parameter analysis indicates that the formation of the binding site takes place during the chemical controlled propagation mechanism of the polymerization reaction. Extending the chemical controlled propagation mechanism via the reversible termination reaction allows for fewer frustrations within the network. Binding parameter research of ethyladenine-9-acetate (EA9A) imprinted poly(methacrylic acid-co-ethylene glycol dimethacrylate) (poly(MAA-co-EGDMA)) networks synthesized via “living” polymerization techniques show increases in template loading capacities and binding affinities compared to standard UV-initiated free radical polymerization. Results from binding studies show a 63% in template loading capacity in EA9A imprinted poly(MAA-co-EGDMA) networks with an increase in fractional double bond conversion, and a 85% increase in template binding affinity for EA9A imprinted poly(MAA-co-EGDMA) networks with equivalent double bond conversions. These results highlight reaction methodologies to tailor imprinted networks and modify the binding characteristics. This will enhance the application potential of “artificial” recognition materials for use in sensors, diagnostic devices, chromatography, and drug delivery carriers.