Responsive hydrogels show obvious superiorities when being employed at detection owing to their polymeric networks and optical properties. Albeit important, the slow response of traditional hydrogels against targets limits their further applications, and enhancing the responsiveness of hydrogel is therefore imperative. Herein, a cryogel with hierarchical structures was designed through adjusting the hydrogel structure by the freezing process to improve the responsive properties, and fabricated for rapid analysis of 17β-estradiol (E2). The cryogel encapsulating the DNA hairpins rapidly adsorbed the complementary DNA isolated from the aptamer in the presence of E2 and activated an efficient hybridization chain reaction (HCR). After integration with a smartphone system, a portable colorimetric sensing platform was created for sensitive detection of E2 with a low detection limit of 0.5 nM. Our work provides a promising way for highly responsive hydrogel-based biosensor design, and broadens their applications in rapid and portable target detection.

中文翻译：

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通过封装程序化 DNA 进行比色检测的基于冷冻凝胶的高响应性传感平台 17β-雌二醇


由于其聚合物网络和光学特性，响应性水凝胶在用于检测时显示出明显的优越性。尽管很重要，但传统水凝胶对靶标的缓慢响应限制了它们的进一步应用，因此提高水凝胶的响应性势在必行。在此，通过冷冻过程调整水凝胶结构以改善响应性能，从而设计了具有分层结构的冷冻凝胶，并制备了用于 17β-雌二醇 （E2） 的快速分析。在 E2 存在下，封装 DNA 发夹的冷冻凝胶迅速吸附从适配体中分离的互补 DNA，并激活高效的杂交链式反应 （HCR）。与智能手机系统集成后，创建了一个便携式比色传感平台，用于灵敏检测 E2，检测限低至 0.5 nM。我们的工作为基于水凝胶的高速响应式生物传感器设计提供了一种有前途的方法，并拓宽了它们在快速和便携式目标检测中的应用。