Computational approach for molecularly imprinted polymers for biomolecules

Although it is relatively simple to prepare molecularly imprinted polymers (MIPs), it may be time consuming. Preparation protocols of MIPs include selection of monomer(s), proper porogen and crosslinker for template molecule, and relative stoichiometry ratio. Using computational methods may decrease required time and cost. To generate input structures for the target molecule and the monomers, conformational distribution in Spartan 16 was used. The complexes were studied in several ratios. After initial geometries were obtained from conformational distribution by molecular mechanics method, these geometries were calculated by semiempirical methods. In the next stage, selected complexes were used including the most stable ones and some others for further investigation. These complexes are also calculated using higher levels of theory with Density Functional Theory (DFT) method. In DFT studies, these structures were calculated with ωB97XD functional in combination with 6-311++G(d,p) basis set as implemented in Gaussian 09. For observing solvent effect on MIP systems, Polarizable Continuum Model (PCM) was used in calculations. Moreover, the effects of cross-linking molecules on the pre-polymerization complex were investigated. Hydrogen bonds are important for the formation and stability of molecularly imprinted polymers. Dispersion effects are also effective in molecular recognition. In this study, these interactions and their effects on MIP were investigated.