Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
Lab Chip. 2012 Nov 7;12(21):4489-98. doi: 10.1039/c2lc40707h.
A potential-resolution strategy for multiplex electrochemiluminescence (ECL) immunoassay on a microfluidic paper-based analytical device (μ-PAD) was demonstrated for the first time, using tris-(bipyridine)-ruthenium(ii) (Ru(bpy)(3)(2+)) and carbon nanodots (CNDs) as the ECL labels for high-throughput ECL immunoassay on μ-PAD. Based on this strategy, simultaneous detection of four tumor markers using only two screen-printed carbon working electrodes (one electrode for two analytes) on an immunodevice consisting of a piece of patterned paper (denoted as μ-PECLI in this work) was realized, which is a simplification of the configuration of traditional μ-PADs. As a further development of μ-PECLI in low-cost and disposable applications, battery-triggered (constant-potential) ECL detection on μ-PECLI was developed, allowing the traditional electrochemical workstation to be abandoned. In addition, to exactly control the output voltage of the battery, a low-cost and simple voltage-controller was designed and fabricated for the first time. The battery-triggered ECL immunoassay principle on μ-PECLI is explained. We found that the simultaneous determination of two analytes in one paper working zone could be achieved by controlling the operational constant-potential (+1.2 V for Ru(bpy)(3)(2+) labels and -1.2 V for CNDs labels (vs. Ag/AgCl auxiliary electrode)) by simply reversing the connection mode. Finally, four tumor markers in human serum samples from the Tumor Hospital were assayed and the results obtained were in acceptable agreement with the reference values from parallel single-analyte test. This battery-triggered μ-PECLI provides a new strategy for high-throughput, low-cost, sensitive, automated and simultaneous multiplex immunoassay and point-of-care diagnosis.
首次提出了一种在微流控纸基分析器件（μ-PAD）上进行多元电化学发光（ECL）免疫分析的潜在解决方案策略，该策略使用三（联吡啶）钌（II）（Ru（bpy）（3）（2+））和碳纳米点（CNDs）作为 ECL 标记物，用于在μ-PAD 上进行高通量 ECL 免疫分析。基于该策略，仅使用两个丝网印刷碳工作电极（一个电极用于两种分析物）在由一块图案化纸张组成的免疫装置（在本工作中表示为μ-PECLI）上实现了四种肿瘤标志物的同时检测，这简化了传统μ-PAD 的配置。作为μ-PECLI 在低成本和一次性应用中的进一步发展，开发了在μ-PECLI 上进行电池触发（恒电位）ECL 检测的方法，从而可以放弃传统的电化学工作站。此外，为了准确控制电池的输出电压，首次设计并制造了一种低成本且简单的电压控制器。解释了μ-PECLI 上电池触发 ECL 免疫分析的原理。我们发现，通过简单地反转连接模式，可以通过控制操作恒电位（+1.2 V 用于 Ru（bpy）（3）（2+）标记物和-1.2 V 用于 CNDs 标记物（相对于 Ag/AgCl 辅助电极））来实现一个纸工作区中两种分析物的同时测定。最后，测定了来自肿瘤医院的人血清样品中的四种肿瘤标志物，并且获得的结果与来自平行单分析物测试的参考值具有可接受的一致性。这种电池触发的μ-PECLI 为高通量、低成本、灵敏、自动化和同时多元免疫分析以及即时诊断提供了新策略。
