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Aliphatic polycarbonate (PC) can be readily hydrolyzed by lipase, but bisphenol A-derived PC (i.e., BPA-PC) lacks enzyme catalysts for their efficient hydrolysis due to the high hydrophobicity and rigidity of its polymer backbone. This study aims to develop an artificial nanozyme for the selective hydrolysis of small-molecule aromatic carbonates as model substrates for BPA-PC. The catalyst is prepared through molecular imprinting of cross-linkable micelles in a one-pot reaction using a thiourea template and a zinc-containing functional monomer. The resulting water-soluble nanoparticle resembles a hydrolytic metalloenzyme to bind the appropriately shaped aromatic carbonate substrate in the active site, with the nearby zinc acting as a cofactor to activate a water molecule for the nucleophilic attack on the carbonate. Catalytic hydrolysis is observed at room temperature and pH 7, with a rate acceleration of 1,000,000 for diphenyl carbonate. 

Hydrolases are used by cells to process key biomolecules including peptides and esters. Previous synthetic mimics of proteases generally only hydrolyze highly active ester derivatives. We report a synthetic catalyst with an acid/base dyad in its active site that hydrolyzes aryl amides near physiological conditions. The aspartic protease mimic achieves substrate selectivity by its imprinted active site, tunable through different template molecules used during molecular imprinting. It can be designed to maintain or override intrinsic activities of aryl amides in a predictable manner. 

Rational design of synthetic catalysts that mimic enzymes in catalysis and substrate selectivity is a long-standing goal of chemists. We report bottom-up synthesis of artificial acetal hydrolase that hydrolyzes its substrate with high selectivity under otherwise impossible neutral and basic conditions. Our synthetic method allows facile modification of the active site, including introduction of a local water pool near the acetal group of the bound substrate to alter the catalytic mechanism, or installment of a secondary catalytic group to enhance the catalytic activity. 

Enzymes have an extraordinary ability to utilize aromatic interactions for molecular recognition and catalysis. We here report molecularly imprinted nanoparticle receptors. The aromatic “wall” material in the imprinted binding site is used to enhance the molecular recognition of aromatic guests that have similar charges, shapes, and sizes but differ in π-electron density. Additionally, aromatic interactions are employed to activate an electron-rich aryl leaving group on a glycoside, mimicking the nucleoside hydrolase of the parasite Trypanosoma vivax.