Anal Chem. 2018 Aug 21;90(16):9830-9837. doi: 10.1021/acs.analchem.8b01860. Epub 2018 Jun 29.
Tubular micromotors composed of a hybrid single-wall carbon nanotube (SW)-FeO outer layer and powered by a MnO catalyst are used for phenylenediamines isomers detection and discrimination. Catalytic decomposition of HO as fuel results in the production of oxygen bubbles and hydroxyl radicals for phenylenediamines dimerization to produce colorful solutions in colorimetric assays. The combination of FeO nanoparticles along with the irregular SW backbone results in a rough catalytic layer for enhanced hydroxyl radical production rate and improved analytical sensitivity. Such self-propelled micromotors act as peroxidase-like mobile platforms that offer efficient phenylenediamines detection and discrimination in just 15 min. Factors influencing the colorimetric assay protocol, such as the navigation time and number of motors, have been investigated. Low limits of detection (5 and 6 μM) and quantification (17 and 20 μM) were obtained for o-phenylenediamine and p-phenylenediamine, respectively. The magnetic properties of the outer SW-FeO hybrid layer allow the reusability of the micromotors in the colorimetric assay. Such attractive performance holds considerable promise for its application in sensing systems in a myriad of environmental, industrial, and health applications.
管状微马达由混合单壁碳纳米管（SW）-FeO 外层组成，并由 MnO 催化剂提供动力，用于苯二胺异构体的检测和区分。HO 的催化分解作为燃料产生氧气气泡和羟基自由基，用于苯二胺二聚化，在比色分析中产生彩色溶液。FeO 纳米颗粒与不规则的 SW 骨干的结合产生了粗糙的催化层，用于提高羟基自由基的产生速率和提高分析灵敏度。这种自推进的微马达作为过氧化物酶样的移动平台，仅在 15 分钟内就能提供高效的苯二胺检测和区分。还研究了影响比色分析协议的因素，例如导航时间和微马达的数量。对于邻苯二胺和对苯二胺，分别获得了低检测限（5 和 6 μM）和定量限（17 和 20 μM）。外层 SW-FeO 混合层的磁性允许微马达在比色分析中重复使用。这种有吸引力的性能为其在环境、工业和健康应用的传感系统中的应用提供了巨大的潜力。
