我们建立了一种新型的光电化学（PEC）和电化学发光（ECL）双功能适配体传感器，用于检测miRNA-126，该传感器采用V2CTx MXene衍生的基于卟啉的金属有机框架负载Ag纳米颗粒（简称为AgNPs@V-PMOF）作为强韧的生物平台。由于V2CTx MXene纳米片中存在V节点，我们使用四取代（4-羧基苯基）卟啉作为配体，制备了基于V的金属有机框架，并通过嵌入Ag+离子形成了AgNPs@V-PMOF肖特基异质结。由于V2CTx基底的快速电子转移和光敏Ag纳米颗粒与V-PMOF之间的能带边缘能级完美匹配，构建的AgNPs@V-PMOF肖特基异质结显示出促进的光生载流子转移，表现出卓越的PEC和ECL性能。此外，由于AgNPs@V-PMOF之间的π-π堆积，范德华力和Ag-N配位的综合作用，大量的miRNA-126的互补DNA链可以固定在AgNPs@V-PMOF上。因此，开发的基于AgNPs@V-PMOF的适配体传感器在PEC和ECL技术下表现出极低的检测限（分别为0.78 fM和0.53 fM），在1.0 fM到1.0 nM范围内，优于大多数报道的miRNA适配体传感器。此外，所提供的双功能适配体传感器具有高选择性、良好稳定性、良好再现性和可接受的再生性，以及在分析活体癌细胞中miRNA-126方面具有潜在的应用前景。这项工作推动了适配体传感器早期和准确诊断癌症标志物的发展，并扩展了MOF在生物传感领域中的应用。

A novel photoelectrochemical (PEC) and electrochemiluminescence (ECL) bifunctional aptasensor has been established for the detection of miRNA-126 using V2CTx MXene-derived porphyrin-based metal-organic framework embedded with Ag nanoparticles (Ag NPs) (denoted as AgNPs@V-PMOF) as a robust bioplatform. Due to the presence of V nodes in V2CTx MXene nanosheets, V-based MOF was prepared using tetrakis(4-carboxyphenyl)porphyrin as ligand, followed by the incorporation of Ag+ ions to form the AgNPs@V-PMOF Schottky heterojunction. Benefiting from the fast electron transfer of the V2CTx substrate and well-matched band-edge energy level of the photosensitive Ag NPs and V-PMOF, the constructed AgNPs@V-PMOF Schottky heterojunction exhibited the promoted transfer of the photogenerated carriers, showing superior PEC and ECL performances. Moreover, a large number of the complementary DNA strand of miRNA-126 can be immobilized over AgNPs@V-PMOF in view of the combined interaction of π-π stacking, van der Waals force, and Ag-N coordination between AgNPs@V-PMOF. Consequently, the developed AgNPs@V-PMOF-based aptasensor illustrated extremely low detection limits of 0.78 and 0.53 fM within a wide range from 1.0 fM to 1.0 nM of miRNA-126 detected by PEC and ECL techniques, respectively, superior to most reported miRNA aptasensors. Also, the provided bifunctional aptasensor demonstrated high selectivity, good stability, fine reproducibility, and acceptable regenerability, as well as promising potential for the analysis of miRNA-126 from living cancer cells. This work puts forward the development of aptasensors for the early and accurate diagnosis of cancer markers and extends the application of MOF in the biosensing field.