Here we report an easily fabricated, plastic-based lateral flow device for carrying out metalloimmunoassays. The device is called ocFlow to emphasize the open-channel design. We have shown that the ocFlow is capable of magnetic microbead (MμB)-based metalloimmunoassays for the detection of two types of immunoconjugates: a model composite (MC) and a sandwich immunoassay for the heart failure marker NT-proBNP. In both assays, Ag nanoparticles (AgNPs) were used as electrochemically detectable labels. NT-proBNP and MC concentrations as low as 750.0 pM and 10.0 pM, respectively, could be detected using the ocFlow device. Four key conclusions can be drawn from the results presented herein. First, immunoconjugates attached to the MμBs can be transported in the flow channel using combined hydrodynamic and capillary pressure passive pumping. Second, the ocFlow device is capable of on-chip storage, resolvation, and conjugate formation of both the MC and NT-proBNP composites. Third, electrochemical detection can be conducted on analytes suspended in serum by rinsing the electrodes with a wash buffer. Finally, and perhaps most significantly, the assay is quantitative and has a detection limit for NT-proBNP in the high picomolar range when the necessary reagents are stored on the device in a dry form.

中文翻译：

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用于电化学检测 NT-proBNP 的塑料侧向流动免疫测定装置

在这里，我们报告了一种易于制造的、基于塑料的横向流动装置，用于进行金属免疫测定。该设备被称为oc Flow 以强调明渠设计。我们已经证明oc Flow 能够进行基于磁性微珠 (MμB) 的金属免疫测定，以检测两种类型的免疫偶联物：模型复合物 (MC) 和用于心力衰竭标志物 NT-proBNP 的夹心免疫测定。在这两种测定中，Ag 纳米颗粒 (AgNPs) 被用作电化学可检测标记。NT-proBNP 和 MC 浓度分别低至 750.0 pM 和 10.0 pM，可以使用oc检测流量装置。从本文呈现的结果中可以得出四个关键结论。首先，连接到 MμBs 的免疫偶联物可以使用组合的流体动力和毛细管压力被动泵送在流动通道中运输。其次，oc Flow 装置能够对 MC 和 NT-proBNP 复合材料进行片上存储、解析和共轭形成。第三，可以通过用洗涤缓冲液冲洗电极来对悬浮在血清中的分析物进行电化学检测。最后，也许最重要的是，当必要的试剂以干燥形式储存在设备上时，该测定是定量的，并且 NT-proBNP 的检测限在高皮摩尔范围内。