漆酶是最常用的用于处理酚类污染物的试剂。为了解决天然漆酶的不稳定性和高成本,我们研究了具有漆酶样活性的核碱基调节的铜纳米材料。各种核碱基,包括腺嘌呤,鸟嘌呤,胞嘧啶,和胸腺嘧啶,由于它们的配位能力,被研究作为Cu2还原和铜纳米材料形成的模板。通过比较结构和催化活性,在相同条件下,胞嘧啶介导的铜纳米材料(C-Cu)具有最佳的漆酶样活性,其他核碱基模板化的铜纳米材料表现出较低的催化活性。利用X射线光电子能谱和密度泛函理论进一步分析了核碱基调控铜纳米材料催化活性的机理。C-Cu可能的催化机理,包括底物吸附,底物氧化,氧结合,和氧气还原,被提议。值得注意的是,核碱基调控的铜纳米酶在各种pH值下表现出较高的稳定性和催化氧化性能,温度,长期储存,和高盐度。结合电化学技术,开发了一种用于测量酚类污染物的便携式电化学传感器。这种新型传感器对邻苯二酚(10-1000μM)具有良好的线性响应,检测限为1.8μM,具有出色的选择性和抗干扰能力。本研究不仅为调控铜纳米材料的漆酶样活性提供了新的策略,而且为有效去除和低成本检测酚类污染物提供了新的工具。
Laccases are the most commonly used agents for the treatment of phenolic pollutants. To address the instability and high cost of natural laccases, we investigated nucleobase-modulated copper nanomaterial with laccase-like activity. Various nucleobases, including adenine, guanine,
cytosine, and thymine, were investigated as templates for Cu2+ reduction and copper nanomaterials formation due to their coordination capacity. By comparing structure and catalytic activity, the
cytosine-mediated copper nanomaterial (C-Cu) had the best laccase-like activity and other nucleobase-templated copper nanomaterials exhibited low catalytic activity under the same conditions. The mechanism of nucleobase regulation of the catalytic activity of copper nanomaterials was further analyzed using X-ray photoelectron spectroscopy and density functional theory. The possible catalytic mechanisms of C-Cu, including substrate adsorption, substrate oxidation, oxygen binding, and oxygen reduction, were proposed. Remarkably, nucleobase-modulated copper nanozymes showed high stability and catalytic oxidation performance at various pH values, temperatures, long-term storage, and high salinity. In combination with electrochemical techniques, a portable electrochemical sensor for measuring phenolic pollutants was developed. This novel sensor exhibited a good linear response to catechol (10-1000 μM) with a limit of detection of 1.8 μM and excellent selectivity and anti-interference ability. This study provides not only a new strategy for the regulation of the laccase-like activity of copper nanomaterials but also a novel tool for the effective removal and low-cost detection of phenolic pollutants.