Controllable synthesis of bimetallic Cu-Zn conjugated polymer microflowers with splendid laccase- and antioxidase-like activities for colorimetric detection of organic pollutants and eliminating cigarette smoke radicals

Although many exquisite laccase-mimicking enzymes have already appeared, these laccase mimic enzymes generally have low catalytic activity and insufficient catalytic function, making it difficult to realize multifaceted applications. Herein, inspired by the chemical structure of Cu-N ligand as an active site in the natural laccase (LAC) and superoxide dismutase (SOD), we report a Cu(II)/Zn(II) bimetallic-organic conjugated polymer microflowers (OCPMFs) with eminent LAC- and antioxidase-like activities. The bimetallic Cu(II)/Zn(II)-OCPMFs was fabricated using a combined ligand-to-metal ratio assembly and solvothermal method. The optimized Cu_4.3Zn_8.6-OCPMF_1.45 material with superior LAC-like activity can be used for the selectively colorimetric detection of both chlortetracycline (CTE) in river water and honey, and tannic acid (TA) in tea wastewater. The limits of detection and linear ranges for both CTE and TA were 0.46 μM and 0.32 μM, as well as 0.5-30 μM and 1-25 μM, respectively. Importantly, the Cu_4.3Zn_8.6-OCPMF_1.45 material with excellent antioxidase-like activity can be used for efficiently scavenging cigarette smoke radicals. This work not only developed an ingenious tactics for adjustably fabricating Cu/Zn-based "All-in-One" mimicking enzymes, but also built a highly sensitive sensor for visualization and selective analysis of pernicious CTE and TA in real water/food samples, as well as exploited a novel cigarette purifier for scavenging noxious cigarette smoke radicals.