Recognition of ephedrine enantiomers by molecularly imprinted polymers designed using a computational approach

A new approach to the computational design of molecularly imprinted polymer s (MIP) specific for ephedrine is presented. A virtual library of functiona l monomers was developed and screened against the template using molecular modelling software. The monomers giving the highest binding score were co-p olymerized with a cross-linker in the presence of ephedrine. Control (blank ) polymers were prepared under the same conditions but in the absence of th e template. A good correlation was found between the modelling results and performance of the materials in an HPLC study. A MIP based on one of the se lected monomers-hydroxyethyl methacrylate-gave a separation of ephedrine en antiomers with a separation factor a of 1.42-2.09 (depending on temperature ). This figure is larger than the a values generally obtained with commerci ally available chiral phases. It is anticipated that the computational appr oach will be of use for the rational design of MIPS and the prediction of p olymer affinity and specificity.