Beijing Key Laboratory of Environmentally Harmful Chemical Analysis, College of Chemistry, Beijing University of Chemical Technology, Beijing 100029, P. R. China.
ACS Appl Mater Interfaces. 2021 Apr 7;13(13):14995-15007. doi: 10.1021/acsami.1c01350. Epub 2021 Mar 26.
A reasonable design of multifarious chemo- and biocatalytic functions within individual nano/microunits is urgently desired for high-performance cascade reactions but has heretofore remained elusive. Herein, glucose oxidase was functionalized with oligonucleotides and steadily chemisorbed on magnetic layered double hydroxides (mLDHs) to construct a multimodal catalytic platform for realizing divergent reactions with heterogeneous and biocatalytic steps. The flowerlike mLDHs served both as an enzyme support and a peroxidase mimic cooperating with enzymes for tandem catalysis. Oligo-DNA connected the enzymes to mLDHs like a bridge, and a stepwise ligand-exchange-assisted coordination mechanism was proposed to explain the robust interaction between DNA and mLDHs. More importantly, DNA significantly improved the bioactivity of the whole system. The acceleration mechanism was attributed to the diffusion tunnels for the substrate/product and enhanced substrates binding on mLDHs. The multimodal catalytic platform was applied for colorimetric and electrochemical sensing of glucose with a low limit of detection and high selectivity. The practical analysis capability of the ultrasensitive sensor was evaluated by detecting glucose in human serum and sweat, showing reliable results, satisfactory recovery, and excellent stability. The strategy of combining mLDHs and enzymes for cascade catalysis provides a universal approach to prepare chemo-enzyme hybrids with high performance, which holds great promise for applications in biosensors and industrial catalysis.
在单个纳米/微单元内合理设计多样化的化学和生物催化功能，对于实现高性能级联反应是迫切需要的，但迄今为止这一目标仍然难以实现。在此，通过将寡核苷酸功能化，并将其稳定化学吸附在磁性层状双氢氧化物（mLDHs）上，构建了一种多模式催化平台，用于实现具有异相和生物催化步骤的发散反应。花状 mLDHs 既可用作酶的载体，又可用作过氧化物酶模拟物，与酶协同进行串联催化。寡核苷酸-DNA 像桥梁一样将酶连接到 mLDHs 上，并提出了逐步配体交换辅助配位机制来解释 DNA 与 mLDHs 之间的强相互作用。更重要的是，DNA 显著提高了整个系统的生物活性。加速机制归因于底物/产物的扩散隧道和增强的 mLDHs 上的底物结合。该多模式催化平台用于葡萄糖的比色和电化学传感，具有低检测限和高选择性。通过检测人血清和汗液中的葡萄糖来评估超灵敏传感器的实际分析能力，结果可靠、回收率满意、稳定性优异。将 mLDHs 和酶结合用于级联催化的策略为制备高性能的化学-酶杂化体提供了一种通用方法，在生物传感器和工业催化领域具有广阔的应用前景。
