Key Laboratory of Analytical Science for Food Safety and Biology (MOE & Fujian Province), Department of Chemistry, Fuzhou University, Fuzhou 350108, People's Republic of China.
Key Laboratory for Green Chemistry of Jiangxi Province, Department of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang 330022, People's Republic of China.
Anal Chem. 2023 Sep 26;95(38):14494-14501. doi: 10.1021/acs.analchem.3c03249. Epub 2023 Sep 14.
Noble-metal nanozymes have demonstrated great potential in various fields. However, aggregation of single-particle nanoparticles severely affects their exposed catalytically active sites to the extent of exhibiting weak enzyme-like activity. Here, we present an organic block surfactant (polyvinylpyrrolidone, PVP) to construct monodisperse water-stable Pt nanoclusters (Pt NCs) for an enhanced immunoassay of cardiac troponin I (cTnI). The PVP-modified Pt NC nanozyme exhibited up to 16.3 U mg peroxidase-mimicking activity, which was mainly attributed to the ligand modification on the surface and the electron-absorbing effect of the ligand on the Pt NCs. The PVP-modified Pt NCs have a lower OH-transition potential, as determined by density functional theory. Under optimized experimental conditions, the enhanced nanozyme immunoassay strategy exhibited an ultrawide dynamic response range of 0.005-50 ng mL for cTnI targets with a detection limit of 1.3 pg mL, far superior to some reported test protocols. This work provides a designable pathway for the design of artificial enzymes with high enzyme-like activity to further expand the practical range of enzyme alternatives.
贵金属纳米酶在各个领域表现出巨大的潜力。然而，单颗粒纳米粒子的聚集严重影响了它们暴露的催化活性位点，导致其表现出较弱的酶样活性。在这里，我们使用一种有机块状表面活性剂（聚乙烯吡咯烷酮，PVP）来构建单分散的水稳定的 Pt 纳米团簇（Pt NCs），以增强对心肌肌钙蛋白 I（cTnI）的免疫分析。PVP 修饰的 Pt NC 纳米酶表现出高达 16.3 U mg 的过氧化物酶模拟活性，这主要归因于表面的配体修饰以及配体对 Pt NCs 的电子吸收效应。通过密度泛函理论计算，PVP 修饰的 Pt NCs 具有更低的 OH 跃迁电位。在优化的实验条件下，增强的纳米酶免疫分析策略对 cTnI 靶标表现出超宽的动态响应范围，为 0.005-50 ng mL，检测限低至 1.3 pg mL，远远优于一些已报道的检测方案。这项工作为设计具有高酶样活性的人工酶提供了一种可设计的途径，以进一步扩展酶替代物的实际应用范围。
