Enzymelike Polymer Catalysts Identified Combinatorially

Novel enzymes for catalyzing chemical reactions can be developed by rational design, but it’s a difficult and slow process. Valentin O. Rodionov of King Abdullah University of Science & Technology, in Saudi Arabia, and coworkers have now developed a combinatorial approach for screening enzyme-inspired polymeric micelles that could speed up the discovery process (ACS Comb. Sci. 2014, DOI: 10.1021/co5001713). They added hydrophobic groups to amphiphilic polymer supports via click chemistry to produce a small library of polymers, each bearing a single type of hydrophobic group. When different combinations of these polymers are blended in water, the polymers collapse into micellar aggregates that, like proteins, have hydrophilic groups on the outside and hydrophobic groups in the interior. Inside the micelles, the functionalized polymers can act cooperatively to catalyze reactions. When the researchers screened the polymer assemblies for catalytic activity in the presence or absence of metal ions, they found productive new catalysts for a range of common organic reactions and validated them by separate synthesis and testing. The researchers haven’t achieved enantioselectivity yet, but that is a goal for the future.