Bai Tingting, Wang Luhai, Wang Meng, Zhu Yefei, Li Wenhan, Guo Zhirui, Zhang Yu
Central Laboratory, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, 210011, China.
State Key Laboratory of Bioelectronics, Jiangsu Key Laboratory for Biomaterials and Devices, School of Biological Science and Medical Engineering & Collaborative Innovation Center of Suzhou Nano Science and Technology, Southeast University, Nanjing, 210096, China.
Biosens Bioelectron. 2022 Jul 15;208:114218. doi: 10.1016/j.bios.2022.114218. Epub 2022 Mar 24.
Achieving metal nanoparticles with high peroxidase activity and visible-light plasmonic property for lateral flow immunoassay has attracted extensive attention in the industry. However, the major challenge lies in establishing a general and robust preparation strategy. In this contribution, we developed a citrate-capped trimetallic Au@Ag-Pt nanorattle by employing seed-mediated growth and galvanic replacement reaction under a convenient condition, which can be translated directly to industrialized production. The rattle-like architecture empowers the Au@Ag-Pt NPs peroxidase-like activity while retaining the plasmonic property with intense color in the visible-light range. According to testing requirements, Au@Ag-Pt NPs-LFIA provides two colorimetric modes: low-sensitivity mode based on the color from their intrinsic plasmonic property and the high-sensitivity mode based on the nanozyme-triggered chromogenic reaction. Human cardiac troponin I (cTnI), one of the most specific markers for cardiac injury, was chosen as the detection model. Mainly, ultrasensitive colorimetric detection of human cTnI was successfully achieved as low as ∼20 pg mL. This strategy is robust to guarantee the stability and repeatability of the peroxidase activity without exact control, which can directly dock with the industrialized production of traditional LFIA strips and be readily adapted for on-demand clinical diagnosis.
制备具有高过氧化物酶活性和可见光等离子体特性的金属纳米颗粒用于侧向流动免疫分析已在该行业引起广泛关注。然而，主要挑战在于建立一种通用且稳健的制备策略。在本研究中，我们通过在便利条件下采用种子介导生长和电化置换反应，开发了一种柠檬酸盐包覆的三金属Au@Ag-Pt纳米摇铃，其可直接转化为工业化生产。这种摇铃状结构赋予Au@Ag-Pt纳米颗粒类过氧化物酶活性，同时在可见光范围内保留具有强烈颜色的等离子体特性。根据检测需求，Au@Ag-Pt纳米颗粒-侧向流动免疫分析提供两种比色模式：基于其固有等离子体特性颜色的低灵敏度模式和基于纳米酶触发显色反应的高灵敏度模式。选择人类心肌肌钙蛋白I（cTnI）作为检测模型，它是心脏损伤最特异的标志物之一。主要地，成功实现了对人类cTnI的超灵敏比色检测，低至约20 pg/mL。该策略稳健，无需精确控制即可保证过氧化物酶活性的稳定性和可重复性，可直接与传统侧向流动免疫分析试纸条的工业化生产对接，并易于应用于按需临床诊断。
