Department of Chemistry, School of Physics and Chemistry, Gwangju Institute of Science and Technology (GIST), 123 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea.
Anal Chem. 2021 Jun 8;93(22):7925-7932. doi: 10.1021/acs.analchem.1c00623. Epub 2021 May 25.
C-reactive protein (CRP) is used as a general biomarker for inflammation and infection. During stroke and myocardial infarction, CRP increases and is present in a broad concentration range of 1-500 μg/mL. Therefore, full-range CRP detection is crucial to identify patients who need close follow-up or intensive treatment after a heart attack. Here, we report the first attempt to develop an electrochemiluminescent lateral flow immunosensor (ECL-LFI) that allows full-range CRP detection. Ru(bpy)-labeled gold nanoparticles (AuNPs) are used as a CRP-targeting probe and a signal generator; they form sandwich immunocomplexes at the test line of the strip and generate strong ECL emission via a Ru(bpy)/tripropylamine system. The ECL-LFI shows high sensitivity in detecting CRP in spiked serum, with a limit of detection of 4.6 pg/mL within 15 min, and a broad detection range of 0.01-1000 ng/mL, which is 2 orders of magnitude broader than that of conventional colorimetric LFI. The clinical usability of the ECL-LFI was evaluated using 30 clinical serum samples (200 ng/mL to 5 mg/mL), which showed a good linear correlation ( = 0.9896), with a clinical chemistry analyzer. The results suggest that the ECL-LFI holds great potential for CRP detection in point-of-care diagnostics.
C-反应蛋白（CRP）被用作炎症和感染的一般生物标志物。在中风和心肌梗死期间，CRP 会增加，其浓度范围广泛，为 1-500μg/mL。因此，全范围 CRP 检测对于确定需要密切随访或在心脏病发作后进行强化治疗的患者至关重要。在这里，我们首次尝试开发一种允许全范围 CRP 检测的电化学发光侧向流动免疫传感器（ECL-LFI）。Ru(bpy)标记的金纳米粒子（AuNPs）用作 CRP 靶向探针和信号发生器；它们在条带的测试线上形成夹心免疫复合物，并通过 Ru(bpy)/三丙胺体系产生强烈的 ECL 发射。ECL-LFI 在检测血清中 CRP 时具有很高的灵敏度，在 15 分钟内检测限为 4.6pg/mL，检测范围为 0.01-1000ng/mL，比传统比色 LFI 宽两个数量级。使用 30 个临床血清样本（200ng/mL 至 5mg/mL）评估了 ECL-LFI 的临床可用性，其与临床化学分析仪具有良好的线性相关性（ = 0.9896）。结果表明，ECL-LFI 在即时诊断中具有很大的 CRP 检测潜力。
