Facile Fabrication of 1-Methylimidazole/Cu Nanozyme with Enhanced Laccase Activity for Fast Degradation and Sensitive Detection of Phenol Compounds

Abstract

Facile construction of functional nanomaterials with laccase-like activity is important in sustainable chemistry since laccase is featured as an efficient and promising catalyst especially for phenolic degradation but still has the challenges of high cost, low activity, poor stability and unsatisfied recyclability. In this paper, we report a simple method to synthesize nanozymes with enhanced laccase-like activity by the self-assembly of copper ions with various imidazole derivatives. In the case of 1-methylimidazole as the ligand, the as-synthesized nanozyme (denoted as Cu-MIM) has the highest yield and best activity among the nanozymes prepared. Compared to laccase, the Km of Cu-MIM nanozyme to phenol is much lower, and the vmax is 6.8 times higher. In addition, Cu-MIM maintains excellent stability in a variety of harsh environments, such as high pH, high temperature, high salt concentration, organic solvents and long-term storage. Based on the Cu-MIM nanozyme, we established a method for quantitatively detecting phenol concentration through a smartphone, which is believed to have important applications in environmental protection, pollutant detection and other fields.

Bacterial Nanocellulose/Copper as a Robust Laccase-Mimicking Bionanozyme for Catalytic Oxidation of Phenolic Pollutants

“…Further, the EDX spectrum confirmed the presence of Cu, C, and O, which are the expected elemental compositions of the nanocomposite (Figure S2). The lower composition of copper (0.74%) is consistent with the laccase enzyme structure, in which the catalytic centers are in lower proportions …”

“…The lower composition of copper (0.74%) is consistent with the laccase enzyme structure, in which the catalytic centers are in lower proportions. 30 The phase composition and crystallinity of the prepared nanozyme were studied using powdered XRD. The XRD pattern (Figure 4b) of BNC/Cu shows two peaks at 15.1 o and 25.9 o , which correspond to the diffraction from (100) and (110) planes of 1α and 1β crystalline bacterial nanocellulose, respectively.…”

Nanozymes: powerful catalytic materials for environmental pollutant detection and degradation

“…[225][226][227] Recently, a lot of nanozyme catalytic systems have been developed to degrade phenolic pollutants. 107,[109][110][111][117][118][119]121,124,[228][229][230][231][232][233][234][235][236][237][238][239] In a representative example, Sun et al studied the degradation process of 17β-estradiol (E2) driven by enzyme-like MnO 2 particles in detail. 236 With the presence of humic acid (HA), four pathways of E2 transformation were revealed, including decomposition, homo-coupling, dehydrogenation, and hetero-coupling (Fig.…”

“…225–227 Recently, a lot of nanozyme catalytic systems have been developed to degrade phenolic pollutants. 107,109–111,117–119,121,124,228–239…”

Bioinspired Coassembly of Copper Ions and Nicotinamide Adenine Dinucleotides for Single-Site Nanozyme with Dual Catalytic Functions

“…Metal–organic frameworks (MOFs), either crystalline or noncrystalline, have been reported to construct diverse nanozymes because MOFs are composed of organic ligands and metals which mimic the active center of metalloenzymes. Due to the inherent advantages in structure designing, the rational constructions of MOF have been used to develop different nanozymes which exhibit excellent catalytic activity. − The innate structural characteristics enable MOFs to perform like single-site catalysts , because metal ions are completely isolated by ligands, such as imidazoles, , aromatic acids, amino acids, , tannic acid, and even nucleotides. , Overall, although the preparation is not always simple, coordination chemistry provides diversity for the rational design of nanozymes, potentially deepening the understanding of catalytic mechanisms and broadening the substrate scope of nanozymes. However, the illustration of using biologically active molecules as ligands is limited, while traditional organic ligands for MOFs lack the ability to enhance the catalysis of metal sites.…”