School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu, 210094, People's Republic of China.
School of Environmental Science, Nanjing XiaoZhuang University, Nanjing, 211171, People's Republic of China.
Mikrochim Acta. 2023 Jul 24;190(8):317. doi: 10.1007/s00604-023-05896-8.
A green electrochemical biosensor was developed based on metal-organic framework (MOF)-catalyzed atom transfer radical polymerization (ATRP) for quantifying miRNA-21, used as the proof-of-concept analyte. Unlike conventional ATRP, Mn-PCN-222 (PCN, porous coordination network) could be used as an alternative for green catalyst to substitute traditional catalysts. First, poly (diallyldimethylammonium chloride) (PDDA) was fixed on the surface of the indium tin oxide (ITO) electrode, and then the Mn-PCN-222 was linked to ITO electrode via electrostatic binding with PDDA. Next, aminated ssDNA (NH-DNA) was used to modify the electrode further by amide reaction with Mn-PCN-222. Then, the recognition and hybridization of NH-DNA with miRNA-21 prompt the generation of DNA-RNA complexes, which further hybridize with Fc-DNA@β-CD-Br and permit the initiator to be immobilized on the electrode surface. Accordingly, β-CD-Br could initiate the polymerization of ferrocenylmethyl methacrylates (FcMMA) under the catalysis of MOF to complete the ATRP reaction. FcMMA presented a distinct electrochemical signal at ~ 0.33 V. Taking advantage of the unique multi-site properties of β-CD-Br and the efficient catalytic reaction induced by Mn-PCN-222, ultrasensitive detection of miRNA-21 was achieved with a detection limit of 0.4 fM. The proposed electrochemical biosensor has been applied to the detection of miRNA-21 in serum samples. Therefore, the proposed strategy exhibited potential in early clinical biomedicine.
基于金属有机框架（MOF）催化原子转移自由基聚合（ATRP）开发了一种绿色电化学生物传感器，用于定量测定 miRNA-21，作为概念验证分析物。与传统的 ATRP 不同，Mn-PCN-222（PCN，多孔配位网络）可用作绿色催化剂替代传统催化剂。首先，将聚二烯丙基二甲基氯化铵（PDDA）固定在氧化铟锡（ITO）电极表面，然后通过 PDDA 与 Mn-PCN-222 的静电结合将 Mn-PCN-222 连接到 ITO 电极上。接下来，通过与 Mn-PCN-222 的酰胺反应，使用氨基化 ssDNA（NH-DNA）进一步修饰电极。然后，NH-DNA 与 miRNA-21 的识别和杂交促使 DNA-RNA 复合物的生成，进一步与 Fc-DNA@β-CD-Br 杂交，并允许引发剂固定在电极表面上。因此，在 MOF 的催化下，β-CD-Br 可以引发二茂铁基甲基丙烯酸甲酯（FcMMA）的聚合，完成 ATRP 反应。FcMMA 在~0.33 V 处呈现出独特的电化学信号。利用β-CD-Br 的独特多位点性质和 Mn-PCN-222 诱导的高效催化反应，实现了对 miRNA-21 的超灵敏检测，检测限低至 0.4 fM。该电化学生物传感器已应用于血清样本中 miRNA-21 的检测。因此，所提出的策略在早期临床生物医学中具有潜力。
