Capturing and Amplifying Impurities from Recombinant Therapeutic Proteins Via Combinatorial Peptide Libraries: A Proteomic Approach

A review. The technique of combinatorial peptide ligand libraries (CPLL), for capturing and amplifying low-abundance proteins in r-DNA products as well as in a no. of other biol. systems, is here analyzed in depth and reviewed. This methodol. is based on a creation of several millions of bio-specific ligands composed of hexapeptides produced in a combinatorial way. When acting on an overloading and satn. principle, high-abundance species are captured in limited amts., whereas low-abundance ones keep being concd. on their bio-specific ligand till substantial harvesting from soln. (the capture process occurring in general from ca. 50% up to 90% efficiency). Examples are given on tracking host-cell impurities present in, e.g., recombinant albumin or monoclonal antibodies. Addnl., other examples of detecting traces of additives and fining agents in such beverages as white and red wines are presented. The unique mechanisms underlying the protein capture in the CPLL methodol., as opposed to capture by homogeneous beads, as represented by ion-exchangers and by hydrophobic resins, are discussed in depth.