MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou, 510631, China; Guangdong Provincial Key Laboratory of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou, 510631, China.
Guangzhou First People's Hospital Nansha Hospital, Guangzhou, 511457, China.
Biosens Bioelectron. 2022 Oct 15;214:114494. doi: 10.1016/j.bios.2022.114494. Epub 2022 Jun 21.
Dry chemistry-based fluorescence or colorimetric immunosensors have been widely applied for point-of-care testing (POCT). However, dry chemistry-based electrochemiluminescence (ECL) immunosensors have not been reported for real sample-to-answer detection. Herein, a dry chemistry-based sample-to-answer, ultrasensitive closed bipolar electrode-ECL (CBP-ECL) immunosensor based on lateral flow assay has been firstly designed for POCT of Cardiac Troponin I (cTnI). The CBP-ECL immunosensor consisted of a fiber material-based chip and an outer shell, which were easily and affordably fabricated by screen-printing and 3D printing, respectively. Additionally, the Ru(Ⅱ)-L-Cys composite, as a self-enhanced ECL probe, was firstly introduced into the sandwich CBP-ECL immunosensor. The ECL signal generated by labeled antibody functionalized Ru(Ⅱ)-L-Cys could quantify cTnI sensitively. Therefore, the immunosensor had a wide linear range (0.001-100 ng/mL) and acceptable sensitivity (0.4416 pg/mL), together with superior specificity and good reproducibility and stability. Furthermore, the immunosensor was capable of detection of cTnI in serum, with recoveries of 97.3-103.4%. For detection of cTnI in plasma samples, the results of the proposed CBP-ECL had a good correlation with those of the clinical method. Importantly, the analysis process easily operated, and completed in 7 min. These results illustrated that the proposed immunosensor effectively combined the high sensitivity of CBP-ECL with the simplicity of lateral flow assay, and provided a promising POCT avenue for early diagnosis of acute myocardial infarction (AMI) and other diseases.
基于干化学的荧光或比色免疫传感器已广泛应用于即时检测（POCT）。然而，基于干化学的电化学发光（ECL）免疫传感器尚未用于实际的样本到答案的检测。本文首次设计了一种基于侧向流动分析的基于干化学的样本到答案、超灵敏的闭路双极电极-ECL（CBP-ECL）免疫传感器，用于 POCT 检测心肌肌钙蛋白 I（cTnI）。CBP-ECL 免疫传感器由纤维材料基片和外壳组成，分别通过丝网印刷和 3D 打印轻松且经济实惠地制造。此外，首次将 Ru（Ⅱ）-L-Cys 复合体能作为自增强 ECL 探针引入夹心 CBP-ECL 免疫传感器中。标记抗体功能化的 Ru（Ⅱ）-L-Cys 产生的 ECL 信号可以灵敏地定量 cTnI。因此，该免疫传感器具有较宽的线性范围（0.001-100 ng/mL）和可接受的灵敏度（0.4416 pg/mL），同时具有良好的特异性和良好的重现性和稳定性。此外，该免疫传感器能够检测血清中的 cTnI，回收率为 97.3-103.4%。对于血浆样本中 cTnI 的检测，所提出的 CBP-ECL 的结果与临床方法具有良好的相关性。重要的是，分析过程易于操作，可在 7 分钟内完成。这些结果表明，所提出的免疫传感器有效地将 CBP-ECL 的高灵敏度与侧向流动分析的简单性相结合，为急性心肌梗死（AMI）和其他疾病的早期诊断提供了一种有前途的 POCT 途径。
