靶向应答的适配体水凝胶越来越广泛应用于分析感应领域，其不同形态由各种策略开发而成。在这里，我们开发了一种结合毛细管自驱动作用的DNA水凝胶薄膜，用于特异性检测肿瘤标志物EpCAM，并进一步引入Exo I进行信号放大。EpCAM适配体被用作交联剂，构建了DNA水凝胶薄膜。当存在EpCAM时，它与EpCAM适配体竞争结合，导致附在毛细管一端的DNA水凝胶薄膜的渗透性改变，并使溶液在毛细管中的流速发生变化，可用于定量检测EpCAM。该方法无需任何仪器，使用方便。溶液在毛细管中行进的距离被定量为EpCAM的浓度，每次检测只需要很少量的DNA水凝胶。EpCAM的检测限值低至0.018 ng mL-1，同时具有良好的稳定性和特异性，显示出在点-of-care测试中的巨大潜力。

Target-responsive aptamer hydrogels are increasingly used in the field of analytical sensing with different morphologies developed by various strategies. Herein, we developed a DNA hydrogel film combined with capillary self-driven action for the specific detection of the tumor marker EpCAM and further introduced Exo I for signal amplification. EpCAM aptamer was used as a crosslinking agent to construct the DNA hydrogel film. When EpCAM was present, it competed for binding with the EpCAM aptamer, resulting in a permeability change of the DNA hydrogel film attached to one end of the capillary, and leading to different solution flow rates through the capillaries that can be utilized for the quantitative detection of EpCAM. This method did not require any instrument and was easy to use. The distance the solution travelled through the capillary was quantified as the concentration of EpCAM, and only a small amount of DNA hydrogel was required for each detection. The detection limit of EpCAM was as low as 0.018 ng mL-1, while offering the advantages of good stability and specificity, and showing great potential in point-of-care testing.