Abstract：
Detecting diseases at the molecular level aids in early diagnosis and treatment. However, traditional immunological detection techniques, such as enzyme-linked immunosorbent assay (ELISA) and chemiluminescence, have detection sensitivities between 10-16 and 10-12 mol/L, which are inadequate for early diagnosis. Single-molecule immunoassays can reach detection sensitivities of 10-18 mol/L and can detect biomarkers that are difficult to measure using conventional detection techniques. It can confine molecules to be detected in a small spatial area and provide absolute counting of the detected signal, offering the advantage of high efficiency and accuracy. Herein, we demonstrate the principles and equipment of two single-molecule immunoassay techniques and discuss their applications. It is shown that the detection sensitivity can be improved by 2-3 orders of magnitude compared to common chemiluminescence or ELISA assays. The microarray-based single-molecule immunoassay technique can test 66 samples in 1 h, which is more efficient than conventional immunological detection techniques. In contrast, microdroplet-based single-molecule immunoassay techniques can generate 107 droplets in 10 min, which is more than 100 times faster than a single droplet generator. By comparing the two single-molecule immunoassay techniques, we highlight our personal perspectives on the current limitations of point-of-care applications and future development trends.
摘要：
在分子水平上检测疾病有助于早期诊断和治疗。然而,传统的免疫学检测技术,如酶联免疫吸附测定（ELISA）和化学发光，检测灵敏度在10-16和10-12mol/L之间，不足以进行早期诊断。单分子免疫测定可以达到10-18mol/L的检测灵敏度,并且可以检测使用常规检测技术难以测量的生物标志物。它可以将待检测的分子限制在较小的空间区域中，并提供检测信号的绝对计数，提供高效率和准确性的优势。在这里，我们展示了两种单分子免疫分析技术的原理和设备，并讨论了它们的应用。结果表明，与常见的化学发光或ELISA测定相比，检测灵敏度可以提高2-3个数量级。基于微阵列的单分子免疫测定技术可以在1小时内测试66个样品，比传统的免疫检测技术更有效。相比之下,基于微滴的单分子免疫测定技术可以在10分钟内产生107个液滴，比单个液滴发生器快100倍以上。通过比较两种单分子免疫测定技术,我们强调我们个人对即时医疗应用目前的局限性和未来发展趋势的看法。
