Herein, a novel zinc-organic gel with self-catalysis-enhanced electrochemiluminescence (ECL) performance was prepared as an emitter for the first time to assemble a biosensor for ultrasensitive detection of microRNA-221 (miR-221) related to liver cancer. Interestingly, Zn²⁺ served as a central ion to coordinate with multidentate ligands 2,4,6-tris(4-carboxyphenyl)-1,3,5-triazine (TATB) at room temperature to form Zn-TATB-MOGs with excellent ECL intensity. More importantly, compared to metal ions (e.g., Al³⁺, Fe³⁺, and Eu³⁺) in the reported MOGs with the role of central ions, Zn²⁺ in Zn-TATB-MOGs not only served as the central ion but also as a coreaction promoter to facilitate the transformation of S₂O₈^2– into free radicals SO₄^•– to react with Zn-TATB-MOGs^•– for further enhancing the ECL signal of Zn-TATB-MOGs. This was the first time to explore the promotion function of metal ions for coreaction reagents and realize the self-catalysis-enhanced ECL of MOGs. Additionally, the double domino-like cascade strand displacement amplification (DC-SDA) methods could overcome the shortcomings of time-consuming procedures and low DNA utilization in traditional cascade-free amplification methods, which significantly shortened the response time of the biosensor and improved the utilization rate of DNA. Consequently, the constructed biosensor achieved ultrasensitive detection of miR-221 with a detection limit of 2.19 aM, which was lower than reported works. This work provided new insight into broadening the development and improving the performance of MOGs as emitters, holding promise for applications in trace detection of biomarkers and early disease diagnosis.

中文翻译：

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具有自催化增强电化学发光的锌有机凝胶作为评估肝癌标志物的发射极


在此，首次制备了一种具有自催化增强电化学发光 （ECL） 性能的新型锌有机凝胶作为发射器，用于组装用于超灵敏检测与肝癌相关的 microRNA-221 （miR-221） 的生物传感器。有趣的是，Zn²⁺ 作为中心离子，在室温下与多齿配体 2,4,6-三（4-羧基苯基）-1,3,5-三嗪 （TATB） 配位，形成具有优异 ECL 强度的 Zn-TATB-MOGs。更重要的是，与已报道的具有中心离子作用的 MOG 中的金属离子（例如，Al³⁺、Fe³⁺ 和 Eu³⁺）相比，Zn-TATB-MOGs 中的 Zn²⁺ 不仅作为中心离子，而且还作为共反应促进剂，促进 S₂O₈^2– 转化为自由基 SO₄^•– 与 Zn-TATB-MOGs^•– 反应用于进一步增强 Zn-TATB-MOGs 的 ECL 信号。这是首次探索金属离子对共反应试剂的促进作用，并实现了 MOGs 的自催化增强 ECL。此外，双多米诺骨牌样级联链置换扩增 （DC-SDA） 方法可以克服传统无级联扩增方法程序耗时、DNA 利用率低的缺点，显著缩短了生物传感器的响应时间，提高了 DNA 的利用率。因此，构建的生物传感器实现了对 miR-221 的超灵敏检测，检出限为 2.19 aM，低于已报道的工作。这项工作为拓宽 MOG 作为发射器的开发和提高性能提供了新的见解，有望在生物标志物的痕量检测和早期疾病诊断中的应用。