title: Improving the imprinting effect by optimizing template:monomer:cross-linker ratios in a molecularly imprinted polymer for sulfadimethoxine.
abstract: Four non-covalently prepared molecularly imprinted polymers (MIPs) for sulfadimethoxine (SDM) were prepared using different ratios of SDM template, methacrylic acid monomer, and ethylene glycol dimethacrylate cross-linker. The imprinting factor (IF) was calculated by comparing the retention of SDM on the imprinted polymer with a comparable non-imprinted polymer. The template:monomer:cross-linker ratio of 1:6:20 resulted in an IF of 3.94 which is higher than found in previous studies. A significant decrease in IF to 0.89 when template:cross-linker ratio was 1:40 contradicts most literature where higher cross-linker concentration improves selectivity. IF was 4.36 when 20% water was added to the acetonitrile HPLC mobile phase during evaluation. Retention of SDM increased as water concentration changed as: 20, 40, 0, 60 and 70%, indicating a combination of shape recognition, hydrogen bonding and hydrophobic interactions contributing to retention of analyte. The MIP has the potential for use in SPE for purification and concentration of SDM and with further optimization, possibly direct HPLC analysis.
authors.affiliation: Susquehanna University, 514 University Avenue, Selinsgrove, PA 17870, USA. toml@susqu.edu
authors.forename: Lou Ann
authors.initials: LA
authors.lastname: Tom
authors.forename: Nicole A
authors.initials: NA
authors.lastname: Schneck
authors.forename: Carla
authors.initials: C
authors.lastname: Walter
mesh_terms: D002851:Chromatography, High Pressure Liquid; D003432:Cross-Linking Reagents / Q000737:chemistry*; D006860:Hydrogen Bonding; D057927:Hydrophobic and Hydrophilic Interactions; D008689:Methacrylates / Q000737:chemistry; D054802:Molecular Imprinting / Q000379:methods*; D011108:Polymers / Q000737:chemistry*; D052616:Solid Phase Extraction; D013412:Sulfadimethoxine / Q000737:chemistry*
chemical_list: D003432:Cross-Linking Reagents; D008689:Methacrylates; D011108:Polymers; D013412:Sulfadimethoxine