Cobalt-based metal organic frameworks: a highly active oxidase-mimicking nanozyme for fluorescence “turn-on” assays of biothiol†

Co-based metal organic frameworks (ZIF-67), working as an oxidase-mimicking nanozyme, can simultaneously catalyze the oxidation of 3,3′,5,5′-tetramethylbenzidine, 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) and Amplex red, exhibiting a high catalytic activity. For Amplex red, two consecutive redox reactions are reported, which is specifically applied for fluorescence “turn-on” detection of biothiols.