Using m-aminophenyl boronic acid (APBA) as a functional monomer, molecularly imprinted polymer (MIP) imprinted with bovine serum albumin (BSA) was fabricated on activated glass spheres under optimized conditions. Key factors in the prepolymerization reaction (between APBA and BSA), such as buffer pH, ionic strength and reaction time, were carefully optimized as previously reported [H.F. Wang, W.Y. Li, X. W. He, et al. Acta Chim. Sinica 65 (2007) 43-48]. The interaction between APBA and BSA during the prepolymerization stage was investigated and optimized, and ideal conditions for protein rebinding experiments were determined as well. Protein rebinding and enriching properties of polymers were studied in single and competitive binding protocols, respectively. The key point of the present paper is that the binding selectivity of polymers may be estimated by the amount of bound-protein recovered from a protein-saturated polymer. Results demonstrated that the selectivity of MIP towards its template protein is superior to that of non-imprinted polymer (NIP). (C) 2008 Elsevier Ltd. All rights reserved.