Zhong Zihui, Dong Jianwei, Xia Ling, He Jincan, Li Gongke
School of Public Health, Guangdong Pharmaceutical University, Guangzhou, 510310, China.
School of Chemistry, Sun Yat-Sen University, Guangzhou, 510006, China.
Anal Bioanal Chem. 2025 May;417(13):2849-2858. doi: 10.1007/s00216-024-05490-8. Epub 2024 Aug 31.
Biomarkers and their concentration levels are critical indicators of metabolomics for clinical applications. Rapid and sensitive analysis methods are essential for realizing timely and efficient quantitation of those significant biomarkers. In this work, a self-driven microfluidic immunosensor was developed for rapid all-in-one separation, enrichment, and detection of biomarkers. This immunosensor was constructed from a cyclic olefin copolymer (COC) channel layer and a polydimethylsiloxane (PDMS) sensing layer. The COC channel layer was modified through protein adsorption, immobilization, and remaining active site blocking. The obtained hydrophilic microchannels not only reduce the nonspecific adsorption, but also provide stable capillary-driven flow generation with linear velocities up to 20 mm/s for aqueous solution auto-injection. The PDMS sensing layer was modified using capture antibodies to accomplish affinity recognition of target biomarkers. Procalcitonin (PCT) and serum amyloid A (SAA) were selected as model biomarkers in the feasibility study on applying the self-driven microfluidic immunosensor to bioassay. The limits of detection of PCT and SAA were 7.9 ng/L and 7.6 μg/L, respectively. Moreover, the whole process can be accomplished within 60 min with excellent selectivity and reproducibility. In clinical serum sample analysis, satisfactory recoveries were achieved for PCT and SAA in the ranges of 85.0-103.0% and 95.5-106.0%, respectively, with relative standard deviations less than 5.3%. The method accuracy was further confirmed by the results of commercial immunoassay kits. This simple and easily operated immunosensor provides a rapid and sensitive biomarker analysis tool, and promotes the further development of automated and easy-to-use microfluidic immunoassays.
生物标志物及其浓度水平是代谢组学在临床应用中的关键指标。快速且灵敏的分析方法对于及时、高效地定量这些重要生物标志物至关重要。在这项工作中，开发了一种自驱动微流控免疫传感器，用于对生物标志物进行快速一体化分离、富集和检测。该免疫传感器由环烯烃共聚物（COC）通道层和聚二甲基硅氧烷（PDMS）传感层构建而成。通过蛋白质吸附、固定化以及剩余活性位点封闭对COC通道层进行修饰。所获得的亲水性微通道不仅减少了非特异性吸附，还为水溶液自动进样提供了稳定的毛细管驱动流，线性速度高达20毫米/秒。使用捕获抗体对PDMS传感层进行修饰，以实现对目标生物标志物的亲和识别。在将自驱动微流控免疫传感器应用于生物测定的可行性研究中，选择降钙素原（PCT）和血清淀粉样蛋白A（SAA）作为模型生物标志物。PCT和SAA的检测限分别为7.9纳克/升和7.6微克/升。此外，整个过程可在60分钟内完成，具有出色的选择性和重现性。在临床血清样本分析中，PCT和SAA的回收率分别在85.0 - 103.0%和95.5 - 106.0%范围内，相对标准偏差小于5.3%，令人满意。商业免疫分析试剂盒的结果进一步证实了该方法的准确性。这种简单易操作 的免疫传感器提供了一种快速且灵敏的生物标志物分析工具，并推动了自动化且易于使用的微流控免疫分析的进一步发展。
