Abstract: Two polymers binding the herbicide 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) were prepared by utilising the technique of the non-covalent molecular imprinting polymerisation in an aqueous medium. The polymers obtained were packed in HPLC columns and the effects of the mobile phase composition on the retention of the imprinting molecule and the selectivity of the stationary phases towards several analogous structures were studied by liquid chromatography. The columns showed a good level of selectivity towards the template and strictly related molecules. It was found that the molecular recognition mechanism acting on the columns was dependent on a combination of ion pair and hydrophobic interactions. (C) 2000 Elsevier Science B.V. All rights reserved