Scientists fromCreative Biolabs have designed and built up a unique tag, HiAffi-tag, which is derived from Protein G, thus has strong binding affinity to most IgG coated on a solid surface. In contrast to His Tag and Strepavidin Binding Motifs used in such libraries, HiAffi-tag enables the best capture of the phage particles to the solid support and the least steric hindrance for proteolysis of the substrate peptides.