School of Life Sciences, Tsinghua University, Beijing 100084, China.
Institute of Biopharmaceutical and Health Engineering, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China.
ACS Biomater Sci Eng. 2022 Sep 12;8(9):3924-3932. doi: 10.1021/acsbiomaterials.2c00600. Epub 2022 Aug 5.
Gold nanoparticle-based point-of-care tests (POCT) are one of the most widely used diagnostic tools for SARS-CoV-2 screening. However, the limitation of their insufficient sensitivity often leads to false negative results in early disease diagnostics. The ongoing pandemic of COVID-19 makes diagnostic tools that are more accurate, sensitive, simple, and affordable in high demand. In this work, we develop a platinum-decorated gold nanoparticle (Au@Pt NP)-based microfluidic chip immunoassay with a sensitivity surpassing that of paper-based detection of nucleocapsid (N) protein, one of the most conserved biomarkers of COVID-19. The synthesized Au@Pt NPs show high stability and catalytic activity in complex environments. The catalytic amplification of Au@Pt NPs enables naked-eye detection of N protein in the low femtogram range (ca. 0.1 pg/mL) and the detection of throat swab samples in under 40 min. This microfluidic chip immunoassay is easy for operation and readout without instrument assistance, making it more suitable for on-site detection and future pathogen surveillance.
基于金纳米颗粒的即时检测（POCT）是用于 SARS-CoV-2 筛查的最广泛使用的诊断工具之一。然而，其灵敏度不足的局限性通常会导致早期疾病诊断中的假阴性结果。当前的 COVID-19 大流行使得更准确、更灵敏、更简单和更经济实惠的诊断工具需求迫切。在这项工作中，我们开发了一种基于铂修饰金纳米颗粒（Au@Pt NP）的微流控芯片免疫分析方法，其灵敏度超过了基于纸基检测的核衣壳（N）蛋白，N 蛋白是 COVID-19 最保守的生物标志物之一。合成的 Au@Pt NPs 在复杂环境中表现出高稳定性和催化活性。Au@Pt NPs 的催化放大作用可实现对纳克级（约 0.1 pg/mL）低浓度 N 蛋白的肉眼检测，以及在 40 分钟内对咽喉拭子样本的检测。这种微流控芯片免疫分析方法易于操作和读取，无需仪器辅助，使其更适合现场检测和未来的病原体监测。
