Smart Engineering of a Self-Powered and Integrated Nanocomposite for Intracellular MicroRNA Imaging

Abstract

Open AccessCCS ChemistryRESEARCH ARTICLE1 Aug 2021Smart Engineering of a Self-Powered and Integrated Nanocomposite for Intracellular MicroRNA Imaging Mei-Rong Cui, Xiang-Ling Li, Hong-Yuan Chen and Jing-Juan Xu Mei-Rong Cui State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023 , Xiang-Ling Li *Corresponding author: E-mail Address: [email protected]n E-mail Address: [email protected] State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023 State Key Laboratory of Materials-Oriented Chemical Engineering, College of Life Science and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816 , Hong-Yuan Chen State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023 and Jing-Juan Xu *Corresponding author: E-mail Address: [email protected] E-mail Address: [email protected] State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023 https://doi.org/10.31635/ccschem.020.202000419 SectionsSupplemental MaterialAboutAbstractPDF ToolsAdd to favoritesTrack Citations ShareFacebookTwitterLinked InEmail Over the past 2 years, many DNA motors have been synthesized and run in living cells, but there are still challenges in designing integrated DNA motors self-powered to enable autonomous intracellular walking without auxiliary additives. Herein, we report a smart strategy based on a DNA motor–MnO2 nanocomposite, which successfully meets these requirements of intracellular analysis and enables sensitive imaging of specific microRNAs (miRNAs) in living cells. Once the motor system enters the cells, MnO2 nanosheets are reduced by intracellular glutathione (GSH), which not only releases the DNA motors that can be activated by the intracellular target miRNA via binding-induced DNA assembly, but also produces cofactors, Mn2+, that can be used as fuels for autonomous and progressive walking. In addition, the false-positive signal generated by GSH on the DNA motor destruction can be greatly reduced due to the consumption of GSH during this process. This strategy not only combines the advantages of previous dynamic nanomachines based on Au nanoparticles but also has merits of higher integration, lower background fluorescence, and self-powered performance, which provide an efficient avenue for visualizing various biomolecules in living cells. Download figure Download PowerPoint Introduction MicroRNAs (miRNAs) are small noncoding RNA molecules that regulate the post-transcriptional process.1,2 They not only participate in the biological processes of cell development, differentiation, apoptosis, and proliferation, but are also related to many pathological processes, such as tumor formation, metastasis, and resistance to drug therapy.3–7 Specifically, miRNAs have become a valuable tumor marker and drug target, highlighting its important roles in the diagnosis and treatment of cancer.8–12 Therefore, imaging miRNA in living cells is desperately needed for the identification and diagnosis of cancer and efficient drug treatment. However, there are still challenges in viewing miRNA in living cells due to the low abundance and complicated physiological environment.13 Since nanoflares were first been proposed by the Mirkin group14 in 2007, nucleic acid–Au nanoparticle (AuNP) nanoprobes have attracted more attention and have been successfully applied in ultrasensitive imaging of miRNA in living cells.15–20 Especially over the past 3 years, inspired by highly complicated and efficient molecular motors presented in living systems, researchers have attempted to design artificial molecular motor nanocomposites (such as robots, springs, and walkers) with excellent biostability for imaging miRNA in living cells and studyi