Study on the Binding Characteristic of Methamidophos‐Specific Molecularly Imprinted Polymer and the Interactions between Template and Monomers

Abstract

Abstract A new molecularly imprinted polymer (MIP) was prepared using methamidophos (MAP) as the template molecule based on non‐covalent interaction. The complexes formed between template and monomers before polymerization were characterized by 1 H NMR titration test, FT‐IR and UV spectrometry study. These studies indicated that a 1:2 molecular complex formed dominantly between MAP and functional monomers. A model mainly involving cooperative hydrogen interaction was proposed by exact placement of functional groups. Association constant was estimated to be 2.894 × 10 6 L 2 /mol 2 . When the initial concentration of MAP was 1.0 mmol L −1 , the affinity capacity of MIP was 4.23 times that of NIP. The binding performance of MIP was modeled with the Freundlich isotherm (FI) and the total number of binding sites was calculated to be 33.97 μmol/g. The MIP showed great homogeneity with a heterogeneity index of m = 0.7356. The specificity of MIP was investigated by single‐analyte binding and molecularly imprinted solid‐phase extraction (MISPE) assays using MAP and other structurally related organophorous pesticides (OPPs). The results indicated that the MIP had a marked preference for MAP.