Clozapine recognition via molecularly imprinted polymers; Bulk polymerization versus precipitation method

Abstract

Two clozapine (CLZ) imprinted polymers were prepared by bulk and precipitation methods. Methacrylic acid and ethylene glycol dimethacrylate (EDMA) were used as functional and crosslinker monomers, respectively. The mean diameter and particle size distribution of the imprinted (P-MIP) and nonimprinted (P-NIP) particles obtained in precipitation method were examined. A conventional batch-adsorption test was applied for characterization of CLZ-polymer interaction. Dissociation constant (KD) and maximum binding sites (Bmax) were calculated using Scatchard analysis. To evaluate the recognition properties of polymers, phenytoin (PTN) binding to each polymer was also studied and compared to CLZ. The imprinting factor (IF) and selectivity factor (α) were also determined for each polymer. Average diameter and polydispersity of P-MIP were 925 nm and 0.17, respectively. The data for P-NIP were 1.05 μm and 0.18. The KD, IF, and α values calculated for P-MIP were 0.45 μM, 3.26, and 17.43, respectively. The data for imprinted polymer, prepared by bulk polymerization (B-MIP), were 14.5 μM, 1.95, and 3.67. These results demonstrated that precipitation polymerization is a more convenient, more effective, and more reproducible method than bulk polymerization for the synthesis of uniformly sized micron and submicron-imprinted polymer particles. © 2011 Wiley Periodicals, Inc.