Staphylococcus aureus protein A-imprinted polyacrylamide gel beads (SpA-IPGB) and imprinted polyacrylamide particles (SpA-IPGP) were synthesized by inverse-phase suspension polymerization and bulk polymerization, using SpA as template, acrylamide (AM) as functional monomers. Recognition capacity studies of the prepared SpA-IPGB and SpA-IPGP on SpA and S. aureus were conducted to determine recognition specificity. Computer imitation docking studies were conducted between template proteins and acrylamide monomer to reveal the recognition mechanism of SpA molecularly imprinted polymer. The results showed that the imprinted gel beads had high adsorption capacity and specificity to the SpA and S. aureus, and the adsorption quantity could reach 6.85 x 10(-3) mu mol/g and 10(3)-10(4) CFU/g. The adsorption capacities of SpA-IPGB on SpA and S. aureus were higher than that of SpA-IPGP and Non-imprinted polyacrylamide gel beads (Non-IPGB). The recognition specificity of SpA-IPGB and SpA-IPGP on S. aureus was much higher than on Escherichia coli and Streptococcus thermophilus. The formation of complementary shape, and hydrogen bonding, electrostatic, and hydrophobic interactions between the imprinting cavities and the template proteins is the driving force for effective and specific recognition of protein imprinted polymer. (C) 2009 Elsevier Ltd. All rights reserved.