▎ 摘　　要

MicroRNAs (miRNAs) are regarded as important biomarkers for disease diagnostics and therapeutics due to their significant regulatory roles in physiologic and pathologic processes. Herein, a versatile nanoprobe based on reduced graphene oxide (rGO) and nucleic acid (DNA) probe was prepared for simultaneously visualize miR451a and miR-214-3p in living cells. In vitro experiments demonstrated that the nanoprobe exhibits excellent selectivity and outstanding sensitivity as low as 1 nM towards miR-451a and miR-214-3p. Moreover, the detection signals of miRNAs have good linearity in their respective concentration ranges (miR-451a: 1-100 nM, Y-1 = 9.3062X(1)+114.85 (R-2 = 0.9965). miR-214-3p: 1-200 nM, Y-2 = 1.4424X(2)+91.312 (R-2 = 0.9961)). Finally, simultaneous dual-color imaging of miR-451a and miR-214-3p in human breast cancer cells (MDA-MB-231) was realized by exploiting the P-1&P-2@rGO nanoprobe. In summary, this simple and effective strategy provides a general sensing platform for highly sensitive detection and simultaneous imaging of dual miRNAs in living cells.