Application of molecular imprinted polymer nanoparticles as a selective solid phase extraction for preconcentration and trace determination of 2,4-dichlorophenoxyacetic acid in the human urine and different water samples

A molecular-imprinted polymer nanoparticles (mip-np) for the selective preconcentration of 2,4-dichlorophenoxyaceticacid (2,4-d) is described. it was obtained by precipitation polymerization from methacrylic acid (the functional monomer),ethylene glycol dimethacrylate (the cross-linker), 2,2?-azobisisobutyronitrile (the initiator) and 2,4-d (the templatemolecule) in acetonitrile solution. the mip-nps were characterized by thermogravimetric analysis, and by scanningelectron microscopy. imprinted 2,4-d molecules were removed from the polymeric structure using acetic acid inmethanol (15:85 v/v %) as the eluting solvent. the sorption and desorption process occur within 10 min and 15 min,respectively. the maximum sorbent capacity of the molecular imprinted polymer is 89.2 mg g?1. the relative standarddeviation and limit of detection for water samples by introduced selective solid phase extraction were 4.2% and1.25 ?g l?1, and these data for urine samples were 4.7% and 1.80 ?g l?1, respectively. the method was applied tothe determination of 2,4-d in the urine and different water samples.