Membrane protein-targeted and dual-miRNAs-activated DNA quadrilateral sensor for accurate tumor cell identification

Tumor cell identification is of crucial significance for cancer diagnosis, and has been focused on cell-surface proteins. In this work, we demonstrated that high specificity can be achieved by integrating cell-surface protein and dual-miRNAs for sensor design. The DNA quadrilateral sensor was designed by assembling an aptamer, two miRNA complementary sequences with multiple complementary strands. The aptamer was specific for the membrane protein of tumor cell. The two miRNAs complementary sequences were employed to build an AND logical signal output in response to intracellular dual miRNAs. Only when membrane protein and dual-miRNAs were present sitmultaneously, the sensor could be operated in cells with high specificity. By imaging various types of cancer cell with differential expression of membrane protein and dual-miRNAs, our sensor exhibited excellent accuracy imaging analysis of target tumor cells.