College of Science, China University of Petroleum (East China), Qingdao, 266580, PR China; Institute of Analytical Chemistry, Department of Chemistry, Zhejiang University, Hangzhou, 310058, PR China.
College of Science, China University of Petroleum (East China), Qingdao, 266580, PR China.
Biosens Bioelectron. 2022 Jan 15;196:113724. doi: 10.1016/j.bios.2021.113724. Epub 2021 Oct 19.
Although nanozyme-based colorimetric assays have been broadly used for biosensing, some limitations such as low catalytic activity of nanozyme, poor sensitivity to analytes and lack of understanding the structure-activity relationship remain unsolved. In this work, we developed an ultrasensitive colorimetric method for biothiols detection based on density functional theory-assisted design of janus Pd-FeO nanozyme. The Pd-FeO dumbbell-like nanoparticles (DBNPs) prepared by seed-mediated approach shows a uniform heterodimeric nanostructure. Ultrasensitive biothiols detection is achieved from two aspects. On one hand, due to the synergistic effect between Pd and FeO in the dumbbell structure, Pd-FeO DBNPs show enhanced peroxidase-mimic activity compared to the individual components. On the other hand, when the target biothiols molecule is present, its inhibition effect on the janus Pd-FeO nanozyme is also significantly enhanced. The above results are confirmed both in experiment and theoretical calculation. Based on the rational design, a simple, highly selective and urtrasensitive colorimetric and quantitative assay for biothiols is developed. The limit of detection (LOD) can reach as low as 3.1 nM in aqueous solution. This assay is also successfully applied to the detection of biothiols in real urine samples. Moreover, the Pd-FeO nanozyme is used to discriminate biothiols levels in normal and cancer cells with high sensitivity at the cell density of 15,000/mL, which demonstrates its great potential in biological and clinical analysis. This work not only shows the great promise of janus bimetallic nanozymes' excellent functionalities but also provides rational guidelines to design high-performance nanozymes for biosensing and biomedical applications.
尽管基于纳米酶的比色分析方法已被广泛应用于生物传感领域，但仍存在一些局限性，例如纳米酶的催化活性低、对分析物的灵敏度差以及缺乏对结构-活性关系的理解。在这项工作中，我们基于密度泛函理论辅助设计的双面 Pd-FeO 纳米酶，开发了一种用于生物硫醇检测的超灵敏比色法。通过种子介导方法制备的 Pd-FeO 哑铃状纳米粒子（DBNPs）呈现出均匀的杂化纳米结构。超灵敏生物硫醇检测是从两个方面实现的。一方面，由于 Pd 和 FeO 在哑铃结构中的协同作用，与单个组分相比，Pd-FeO DBNPs 表现出增强的过氧化物酶模拟活性。另一方面，当存在目标生物硫醇分子时，其对双面 Pd-FeO 纳米酶的抑制作用也显著增强。实验和理论计算都证实了上述结果。基于合理的设计，开发了一种简单、高选择性和超灵敏的比色定量生物硫醇分析方法。在水溶液中的检测限（LOD）可低至 3.1 nM。该方法还成功地应用于真实尿液样本中生物硫醇的检测。此外，该 Pd-FeO 纳米酶还用于以高灵敏度区分正常和癌细胞中的生物硫醇水平，在细胞密度为 15,000/mL 时，其灵敏度非常高，这表明其在生物和临床分析中具有巨大的应用潜力。这项工作不仅展示了双面双金属纳米酶优异功能的巨大前景，还为设计用于生物传感和生物医学应用的高性能纳米酶提供了合理的指导。
