Fe(II)(4)L(4) Tetrahedron-Assisted Three-Way Junction Probe for Multiple miRNA Detection

[Image: see text] MicroRNAs (miRNAs) modulate a variety of cellular signaling pathways and play a vital role in cell-to-cell communication. The overlapped expression of a certain miRNA is commonly reported to be related to cancers. Therefore, combined detection of multiple miRNAs is of great significance for cancer diagnosis. Herein, we developed a Fe(II)(4)L(4) tetrahedron-assisted three-way junction (3WJ) probe, which exhibited a higher stability than the normal 3WJ probe, for multiple miRNA detection. In this method, the simultaneous existence of miRNA-21 and miRNA-144 triggers the release of the Y3 sequence in the Fe(II)(4)L(4) tetrahedron-assisted 3WJ probe, which in turn triggers subsequent CRISPR-Cas12a-assisted rolling circle amplification. Based on this, simultaneous detection of miRNA-21 and miRNA-144 was achieved. Furthermore, we also applied this method to the detection of miRNAs in clinical samples and achieved good agreement with quantitative real-time polymerase chain reaction (qRT-PCR), indicating its significant potentials in early diagnosis and treatment of cancer.