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Abstract: The adsorption isotherms of D- and L-phenylalanine anilide (PA) on an L-phenylalanine anilide imprinted stationary phase have been determined using staircase frontal analysis, An aqueous buffer- organic solvent mixture has been used as mobile phase. The measurements were done at temperatures of 40, 50, 60 and 70 degrees C for sample concentrations ranging between 5.10(-4) to 1 g/l. It was found that the adsorption data fit well to both the Freundlich and the Bi-Langmuir isotherm models. Examination of the best values of the numerical coefficients of the Bi-Langmuir model shows that the site class representing the binding sites with the highest binding energy exhibits a very low saturation capacity for the non-imprinted enantiomer, indicating a high selectivity for the imprinted L- enantiomer. The low energy site class also shows some selectivity for the L-enantiomer. Mass transfer rate coefficients were obtained for each single breakthrough curve by using the transport model of chromatography. It was found that the mass transfer coefficient of L- PA increases very rapidly with the sample concentration while there is only a slight increase for the other enantiomer. (C) 1998 Elsevier Science B.V. All rights reserved