Washing is a standard step for enzyme-linked immunosorbent assays (ELISA) performed on a paper-based chip, in which nonspecific-binding antibodies and antigens should be removed completely from the paper surface. In this study, a novel three-dimensional (3D) washing strategy using a heating ring-oven was carried out on a paper-based chip. Compared with a plane washing mode by a ring-oven, this 3D washing strategy obtained a lower background, as gravity played an important role in the washing step. The paper-based chip was placed on a 3D plastic holder and the waste area was connected to a heating ring. Use of a heating waste area meant that the nonspecific-binding protein was continuously carried to the waste area through gravity and capillary action. The angle between the plastic holder and the ring plane was carefully selected. The effect of washing on different parts of the detection area was investigated by upconversion fluorescence and chemiluminescence (CL). This novel 3D washing strategy was performed for carcinoembryonic antigen detection through CL and a lower detection limit of 2 pg ml-1 was obtained. This approach provides an effective washing strategy to remove nonspecific-binding antibody from a paper-based immunodevice.

中文翻译：

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纸基免疫装置的三维环形烤箱清洗技术。

洗涤是在纸基芯片上进行的酶联免疫吸附测定（ELISA）的标准步骤，其中非特异性结合抗体和抗原应从纸表面完全去除。在这项研究中，在纸基芯片上使用加热环烤箱进行了新颖的三维（3D）洗涤策略。与环形烘箱的平面洗涤模式相比，这种3D洗涤策略具有较低的背景，因为重力在洗涤步骤中起着重要的作用。纸基芯片放置在3D塑料支架上，废料区连接到加热环。使用加热废物区意味着非特异性结合蛋白通过重力和毛细作用被连续地带到废物区。仔细选择塑料支架和环形平面之间的角度。通过上转换荧光和化学发光（CL）研究了洗涤对检测区域不同部分的影响。通过CL对癌胚抗原进行了这种新颖的3D洗涤策略，并获得了2 pg ml-1的下限。该方法提供了一种有效的洗涤策略，以从纸质免疫装置中去除非特异性结合抗体。