The Ph.D.-12 TM Phage Display Peptide Library Kit was purchased from New England BioLabs Inc. The dodecapeptide library consisted of 2.7610 9 electroporated sequences (1.5610 13 pfu/mL). The mAb was purified from the ascites uid of mice inoculated with the hybridma cells secreting A9E8 by affinity chromatography using rProtein G Agorose (Invitrogen, Carlsbad, CA,USA) according to the manufacturer's instructions. The concentration of the purified protein was determined using the Bradford Protein Assay Kit (Beyotime, Shanghai, China). Three successive rounds of biopanning were carried out according to the manufacturer's instruction manual. Briey, one well of a 96well microtiter plate was coated with 10 mg/mL of mAb A9E8 in coating buffer (0.1 M NaHCO 3 , pH 8.6) overnight at 4uC, followed by blocking with blocking buffer (0.1 M NaHCO 3 , pH 8.6, 0.02% NaN3, and 5 mg/ml BSA) for 2 h at 4uC. The phage library (1.5610 11 phages/100 mL) was added to the blocked wells and the plate incubated for 1 h at room temperature. The unbound phages were removed by successive washings with TBS buffer (50 mM Tris-HCl, pH 7.5, 150 mM NaCl) containing gradually increased concentrations (0.1%, 0.3%, and 0.5%) of Tween-20, and the bound phages were eluted by 0.2 M glycine-HCl containing 1 mg/mL BSA (pH 2.2) and immediately neutralized with 1 M Tris-HCl (pH 9.1). The eluted phages were amplified by infecting E. coli (ER2738), and were titered on LB/IPTG/Xgal plates for the subsequent rounds of selection. The output to input ratio was calculated as follows: (titer of the amplified eluent phages/titer of the input phages (1.5610 11 ))6100%.