The Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
Nanoscale. 2023 Sep 14;15(35):14301-14318. doi: 10.1039/d3nr02345a.
Nanozymes are inorganic, organic and metal-organic framework nanoparticles that reveal catalytic functions by emulating native enzyme activities. Recently, these nanozymes have attracted growing scientific interest, finding diverse analytical and medical applications. However, the catalytic activities and functions of nanozymes are limited, due to the lack of substrate binding sites that concentrate on the substrate at the catalytic site (molarity effect), introduce substrate specificity and allow functional complexity of the catalysts (cascaded, switchable and cooperative catalysis). The modification of nanozymes with functional nucleic acids provides means to overcome these limitations and engineer nucleic acid/nanozyme hybrids for diverse applications. This is exemplified with the synthesis of aptananozymes, which are supramolecular aptamer-modified nanozymes. Aptananozymes exhibit combined specific binding and catalytic properties that drive diverse chemical transformations, revealing enhanced catalytic activities, as compared to the separated nanozyme/aptamer constituents. Relationships of structure-catalytic functions in the aptananozyme constructs are demonstrated. In addition, modification of nanozymes exhibiting multimodal catalytic functions with aptamers allows the engineering of nanozyme-based bioreactors for cascaded catalysis. Also, the functionalization of reactive oxygen species (ROS)-generating nanozymes with cancer cell-recognizing aptamers yields aptananozymes for targeted chemodynamic treatment of cancer cells and cancer tumors elicited in mice. Finally, nucleic acid-modified enzyme (glucose oxidase)-loaded metal-organic framework nanoparticles yield switchable biocatalytic nanozymes that drive the ON/OFF biocatalyzed oxidation of Amplex Red, dopamine or the generation of chemiluminescence. Herein, future challenges of the topic are addressed.
纳米酶是模拟天然酶活性而表现出催化功能的无机、有机和金属有机骨架纳米粒子。最近，这些纳米酶引起了越来越多的科学兴趣，在分析和医学领域有广泛的应用。然而，由于缺乏集中在催化部位的底物结合位点（浓度效应），纳米酶的催化活性和功能受到限制，这些结合位点可以浓缩底物、引入底物特异性并允许催化剂具有功能复杂性（级联、可切换和协同催化）。用功能性核酸修饰纳米酶为克服这些限制并设计用于各种应用的核酸/纳米酶杂化体提供了手段。这可以通过合成适体纳米酶来举例说明，适体纳米酶是超分子适体修饰的纳米酶。适体纳米酶表现出结合特异性和催化性能的结合，驱动多种化学转化，与分离的纳米酶/适体成分相比，表现出增强的催化活性。证明了适体纳米酶结构-催化功能之间的关系。此外，用适体修饰具有多模式催化功能的纳米酶，可以构建基于纳米酶的生物反应器用于级联催化。另外，用识别癌细胞的适体对产生活性氧物种（ROS）的纳米酶进行功能化，得到用于靶向化学动力学治疗癌细胞和引发小鼠肿瘤的适体纳米酶。最后，用核酸修饰的酶（葡萄糖氧化酶）负载的金属有机骨架纳米粒子得到可切换的生物催化纳米酶，可以驱动 Amplex Red、多巴胺或化学发光的 ON/OFF 生物催化氧化。本文还讨论了该主题的未来挑战。
