Mohsen Daraei Omid, Singh Avinash Kumar, Mohapatra Saswat, Mallick Mohammad Sadman, Kotnala Abhay, Shih Wei-Chuan
Department of Electrical and Computer Engineering, University of Houston, 4800 Calhoun Road, Houston, TX 77204 USA.
Department of Biomedical Engineering, University of Houston, 4800 Calhoun Road, Houston, TX 77204 USA.
NPJ Biosens. 2025;2(1):26. doi: 10.1038/s44328-025-00047-w. Epub 2025 Jul 30.
Tumor-derived circulating small extracellular vesicles (sEVs) are a promising class of non-invasive biomarkers for disease diagnosis. However, their quantitative detection remains challenging due to their small size and the complexity of blood plasma. Therefore, sample preparation, such as purification and fluorescence labeling, is required. This study presents a purification-free approach using a microfluidic chip integrated with PlAsmonic NanO-apeRture lAbel-free iMAging (PANORAMA) for label-free single sEV characterization in plasma. CD63, CD9, and CD81 antibodies, specific for most sEVs surface antigens, are functionalized on arrayed gold nanodisks on invisible substrates (AGNIS) for selective capture. The automated microfluidic platform minimizes operational errors and biases and enables precise control of flow rates, directions, media volume, and composition for optimization. This platform requires only 20 µL of plasma, and the analysis is completed within 60 minutes. This platform shows great potential as a sensitive and effective tool for detecting and characterizing circulating sEVs without purification or labeling.
肿瘤来源的循环小细胞外囊泡（sEVs）是一类很有前景的用于疾病诊断的非侵入性生物标志物。然而，由于其尺寸小以及血浆的复杂性，对它们进行定量检测仍然具有挑战性。因此，需要进行样品制备，如纯化和荧光标记。本研究提出了一种无需纯化的方法，使用集成了等离子体纳米孔无标记成像（PANORAMA）的微流控芯片，用于在血浆中对单个sEV进行无标记表征。针对大多数sEV表面抗原具有特异性的CD63、CD9和CD81抗体，在不可见底物上的阵列金纳米盘（AGNIS）上进行功能化，以实现选择性捕获。自动化微流控平台将操作误差和偏差降至最低，并能够精确控制流速、方向、介质体积和组成以进行优化。该平台仅需20微升血浆，且分析在60分钟内完成。该平台作为一种无需纯化或标记即可检测和表征循环sEV的灵敏且有效的工具，具有巨大潜力。
