Bisphenol A (BPA)-imprinted polyethersulfone (PES) microfibers for the recognition of BPA were prepared by means of wet-spinning method based on the liquid-liquid phase separation technique. Two kinds of the BPA-imprinted microfibers were fabricated with the diameters of about 85 mu m and 265 pm, respectively. Extraction of BPA from the microfibers; was carried out by immersing the imprinted microfibers into ethanol. In the recognition experiments, the binding amounts were about 24.0, 43.0, and 70.0 mu mol/g for the nonimprinted microfibers, whereas those were about 50.0, 87.0, 120.0 mu mol/g for the imprinted PES microfibers with the diameter of about 85 mu m in 100, 200, and 400 mu M BPA solution, respectively. Both of the bindin- amounts and the adsorption rate for the imprinted microfibers with smaller diameter were higher than that for the microfibers with larger diameters. The selectivity results indicated that the BPA-imprinted microfibers showed higher recognition coefficient (alpha) for BPA than phenol. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 114: 4036-4041, 2009