Wang Ying, Yin Li, Qu Guangxu, Leung Chung-Hang, Han Lei, Lu Lihua
College of Chemistry and Pharmaceutical Sciences, Qingdao Agricultural University, Qingdao 266109, China.
State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao 999078, China.
Anal Chem. 2023 Aug 15;95(32):11960-11968. doi: 10.1021/acs.analchem.3c01569. Epub 2023 Aug 2.
Single-atom nanozymes (SAzymes) are novel mimic-enzyme materials with atomically doped active sites. They play a pivotal role in the field of nanozymes because of their excellent catalytic activities, high utilization efficiency of the metal atoms, and simple model of active sites. Herein, the peroxidase (POD)-like SAzymes with high-loading iridium (Ir) (5.31%) on graphene oxide (GO) nanosheets [Ir(III)/GO] were prepared through a coordination reaction between the Ir(III) complex and the oxygen-containing groups in GO. The preparation strategy avoids nitrogen doping and pyrolysis procedures which are the usually used strategies to improve the GO-based enzyme mimic activity. Ascribed to the highly active Ir atoms, Ir(III)/GO SAzymes demonstrate outstanding POD-like activity without the oxidase-like activity. In advantage of the excellent POD-like activity, a simple and sensitive colorimetric pesticide detection platform is established. The developed sensing platform offers an excellent "switch-on" pirimicarb (PIB) detection in the linear range of 10-300 nM with a limit of detection (LOD) of 2.81 nM. Moreover, the detection platform was fabricated into a portable test kit, which is composed of a test swab and sample processing tube. In the aid of a color-reading APP, the test kit can detect PIB with the LOD of 3.31 nM. It is astonishing to get this excellent detection sensitivity just using the simple colorimetric strategy. This work not only provides a novel strategy to synthesize Ir-based SAzymes but also exhibits the super capability of Ir(III)/GO in the biosensing field.
单原子纳米酶（SAzymes）是一类具有原子掺杂活性位点的新型模拟酶材料。由于其优异的催化活性、高金属原子利用率以及简单的活性位点模型，它们在纳米酶领域发挥着关键作用。在此，通过铱（Ir）（III）配合物与氧化石墨烯（GO）纳米片层中的含氧基团之间的配位反应，制备了在氧化石墨烯纳米片上具有高负载量铱（5.31%）的类过氧化物酶（POD）单原子纳米酶[Ir（III）/GO]。该制备策略避免了氮掺杂和热解程序，而这两种程序是通常用于提高基于GO的酶模拟活性的策略。归因于高活性的Ir原子，Ir（III）/GO单原子纳米酶表现出出色的类POD活性，而没有类氧化酶活性。凭借优异的类POD活性，建立了一种简单灵敏的比色法农药检测平台。所开发的传感平台在10 - 300 nM的线性范围内对抗蚜威（PIB）具有出色的“开启”检测能力，检测限（LOD）为2.81 nM。此外，该检测平台被制成便携式测试试剂盒，其由测试拭子和样品处理管组成。借助颜色读取APP，该测试试剂盒能够以3.31 nM的LOD检测PIB。仅使用简单的比色策略就能获得如此出色的检测灵敏度，令人惊讶。这项工作不仅提供了一种合成基于Ir的单原子纳米酶的新策略，还展示了Ir（III）/GO在生物传感领域的卓越能力。
