Effects of Charge Density on the Recognition Properties of Molecularly Imprinted Polymeric Hydrogels

Molecular imprinting is a technique used to synthesize polymers that display selective recognition for a given molecule of interest. In this study, the role of hydrogel electrostatic charge density on the recognition and selectivity properties of protein-imprinted hydrogels was explored, and the effect of variations of the template extraction protocol on the MIP recognition properties were also Studied in depth. Using 3-methacrylamidopropyltrimethylanimonium chloride (MAPTAC) as a cationic monomer and 2-acrylamido-2-methylpropanesulfonic acid (AMPS) as an anionic monomer, a number of acrylamide-based hydrogels with varying positive and negative charge densities were prepared. The gels exhibited template recognition properties that were dependent oil both the monomer charge density and on whether the chosen monomer carried a positive or negative charge. In addition, we found that common agents used in template extraction may be responsible for the specific and selective binding properties exhibited by molecularly imprinted polymers in many published studies.