In this study, we report an inkjet printing-based method for the immobilization of different reactive analytical reagents on a single microchannel for a single-step and homogeneous solution-based competitive immunoassay. The immunoassay microdevice is composed of a poly(dimethylsiloxane) microchannel that is patterned using inkjet printing by two types of reactive reagents as dissolvable spots, namely, antibody-immobilized graphene oxide and a fluorescently labeled antigen. Since nanoliter-sized droplets of the reagents could be accurately and position-selectively spotted on the microchannel, different reactive reagents were simultaneously immobilized onto the same microchannel, which was difficult to achieve in previously reported capillary-based single-step bioassay devices. In the present study, the positions of the reagent spots and amount of reagent matrix were investigated to demonstrate the stable and reproducible immobilization and a uniform dissolution. Finally, a preliminary application to a single-step immunoassay of C-reactive protein was demonstrated as a proof of concept.

在这项研究中，我们报告了一种基于喷墨印刷的方法，用于将不同反应性分析试剂固定在单个微通道上，以进行基于步骤和均质溶液的竞争性免疫测定。免疫测定微装置由聚二甲基硅氧烷微通道组成，该微通道使用两种类型的反应试剂作为可溶点，即喷墨固定的氧化石墨烯和荧光标记的抗原，通过喷墨打印进行了图案化。由于可以在微通道上精确定位并选择性地滴定纳升级的试剂滴，因此将不同的反应试剂同时固定在同一微通道上，这在以前报道的基于毛细管的单步生物测定装置中很难实现。在目前的研究中，研究了试剂斑点的位置和试剂基质的量，以证明稳定且可重现的固定化和均匀的溶解。最后，证明了对C反应蛋白的一步免疫测定的初步应用是一种概念证明。