Abstract: In a first step towards chemical sensors using molecular imprinted materials, the complexing characteristics of diethyl 4-nitrobenzylphosphonate, an organophosphate pesticide analogue, have been studied. Two molecules have been assessed as potential interacting moieties, specifically a fluoroalcohol and an aromatic acid. The interactions have been first characterized by regular methods, such as 1H, 31P NMR and IR spectroscopy. These showed a stoichiometry 1/1 for both complexes and association constants, respectively, close to 40á¦á10 and 12á¦á2áM-1. In a second step, isothermal titration calorimetry was used and a method was developed to obtain low-association constants. The association constant could be obtained for the fluoroalcohol ligand and was found equal to 63á¦á0.7áM-1. For the acidic molecule, an appropriate model could not be found, preventing the evaluation of this constant
Author keywords: pesticides, isothermal titration calorimetry, molecular imprinted polymers, sensors