Department of Chemistry, The University of Texas at Austin, 105 E. 24th Street, Stop A5300, Austin, Texas 78712-1224, USA.
Analyst. 2022 May 30;147(11):2460-2469. doi: 10.1039/d2an00685e.
Here we report an easily fabricated, plastic-based lateral flow device for carrying out metalloimmunoassays. The device is called Flow to emphasize the open-channel design. We have shown that the Flow 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 Flow 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 Flow 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.
我们在此报告一种易于制备的基于塑料的侧向流装置，用于进行金属免疫分析。该装置被称为 Flow，以强调其开放式通道设计。我们已经证明，Flow 能够进行基于磁性微珠 (MμB) 的金属免疫分析，用于检测两种免疫缀合物：一种是模型复合物 (MC)，另一种是用于心力衰竭标志物 NT-proBNP 的夹心免疫分析。在这两种分析中，均使用了银纳米颗粒 (AgNPs) 作为电化学可检测标记物。使用 Flow 装置可以检测到低至 750.0 pM 和 10.0 pM 的 NT-proBNP 和 MC 浓度。从本文呈现的结果中可以得出四个关键结论。首先，附着在 MμB 上的免疫缀合物可以通过组合的流体动力和毛细压力被动泵送在流道中运输。其次，Flow 装置能够在芯片上存储、重新溶解以及 MC 和 NT-proBNP 复合物的缀合形成。第三，通过用洗涤缓冲液冲洗电极，可以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装置上时，该测定是定量的，并且对 NT-proBNP 的检测限在皮摩尔范围内。
