Nanozymes with Modulable Inhibition Transfer Pathways for Thiol and Cell Identification

Abstract

The elementary mechanism and site studies of nanozyme-based inhibition reactions are ambiguous and urgently require advanced nanozymes as mediators to elucidate the inhibition effect. To this end, we develop a class of nanozymes featuring single Cu–N catalytic configurations and B–O sites as binding configurations on a porous nitrogen-doped carbon substrate (B₆/Cu_SA) for inducing modulable inhibition transfer at the atomic level. The full redistribution of electrons across the Cu–N sites, induced by B–O sites incorporation, yields B₆/Cu_SA with enhanced peroxidase-like activity versus Cu_SA. More importantly, Cu_SA with single Cu–N sites features in cysteine binding and expresses a competitive inhibition through coordination bonds, with an inhibition constant of 0.048 mM. Benefiting from the modulable binding way in nanozymes, B₆/Cu_SA possesses mixed binding approaches for cysteine through noncovalent bonds and delivers a record-mixed inhibition interaction with a competitive inhibition constant of 0.054 mM and a noncompetitive inhibition constant of 0.71 mM. Based on the modulable inhibition of B₆/Cu_SA and Cu_SA, a multichannel sensor array accomplishes the detection of various cancer cells, normal cells, and thiols. The design principle of this work is endowed with guidelines for the preliminary inhibition mechanism evaluation of massive potential thiols, cell discrimination, and disease prediction.