Nanodevice-based imaging of miRNA in vivo by eliminating blood interference

Abstract

In vivo imaging analysis of tumor-associated miRNA is of great significance for the study of tumor occurrence and development as well as for clinical tumor diagnosis and prognosis, but the interference of circulating miRNA in the blood that is the same as the target miRNA makes this vision difficult to achieve. Here, we developed a smart DNA nanodevice that can respond to glutathione (GSH), a microenvironmental factor excessive in tumor cells, and be activated by the target miRNA after being unlocked by GSH, and then output the fluorescence signal of the miRNA. Successful imaging analysis of miR-21, a well-known tumor-associated miRNA, in tumor-bearing mice is achieved. Results show that benefited from the GSH-responsive nanodevice, amplified and accurate fluorescence images of the tumor-associated miR-21 with low background signal in blood and other tissues can be obtained. The concept and its successful implementation in this work promote the development of in vivo miRNA analysis, which will further have great prospects in tumor research and diagnosis.