Abstract:
Bisphenol compounds (BPA, BPS, BPAF, etc.) are one class of the most important and widespread pollutants that poses severe threat to human health and the ecological environment. Because of the presence of multiple bisphenols in environmental and food samples, it is urgent and challenging to develop a rapid and cheap technique for simultaneously detecting BPA and its analogues. In this study, a series of M-N-C (M = Cu, Mg, Ni, Co, Fe, K) single-atom nanozymes (SAzymes) were created by simulating the structure of natural enzyme molecules, which were used as novel sensing platform for the fabrication of electrochemical sensors. Through systematic screening and characterization, it was interestingly discovered that the electrochemical sensor based on Cu-N-C SAzymes exhibited the best sensing performance for bisphenols among all SAzymes, which catalyzed not only BPA like tyrosinase, but also showed excellent catalytic capacity beyond tyrosinase (tyrosinase has no catalytic activity for BPS, BPAF, etc.), and achieved potential-resolved simultaneous rapid detection of BPA, BPS and BPAF. Further structure-activity relationship and catalytic mechanism characterizations of Cu-N-C SAzymes revealed that the presence of single atom Cu was predominantly in the form of Cu+ and Cu2+, which were anchored onto graphene nanosheet support through four coordination bonds with pyridinic N and pyrrolic N and acted as highly efficient active centers for electrocatalytic oxidation of bisphenols. The developed electrochemical sensing method exhibited excellent selectivity, sensitivity, and reliability for the rapid detection of multiple bisphenols in actual samples.
摘要:
双酚化合物(BPA,BPS,BPAF,等。)是对人类健康和生态环境构成严重威胁的最重要和最广泛的污染物之一。由于环境和食品样品中存在多种双酚,开发一种快速、廉价的同时检测BPA及其类似物的技术是紧迫和具有挑战性的。在这项研究中,一系列M-N-C(M=Cu,Mg,Ni,Co,Fe,K)单原子纳米酶(SAzymes)是通过模拟天然酶分子的结构而产生的,作为制备电化学传感器的新型传感平台。通过系统的筛选和表征,有趣的是,基于Cu-N-CSAzymes的电化学传感器在所有SAzymes中表现出对双酚的最佳传感性能,不仅催化BPA如酪氨酸酶,但也显示出优于酪氨酸酶的催化能力(酪氨酸酶对BPS没有催化活性,BPAF,等。),并实现了BPA的电位分辨同时快速检测,BPS和BPAF。Cu-N-CSAzyes的进一步结构-活性关系和催化机理表征表明,单原子Cu的存在主要以Cu和Cu2的形式存在。通过与吡啶N和吡咯N的四个配位键固定在石墨烯纳米片载体上,并作为高效的活性中心电催化氧化双酚。所开发的电化学传感方法表现出优异的选择性,灵敏度,和可靠性的快速检测实际样品中的多种双酚。