Catalytic Molecular Imaging of MicroRNA in Living Cells by DNA-Programmed Nanoparticle Disassembly

• Published in: Angewandte Chemie International Edition Vol. 55; no. 9; pp. 3073 - 3076
• Main Authors: He, Xuewen, Zeng, Tao, Li, Zhi, Wang, Ganglin, Ma, Nan
• Format: Journal Article
• Language: English
• Published: Germany Blackwell Publishing Ltd 24-02-2016; Wiley Subscription Services, Inc
• Edition: International ed. in English
• Subjects: Abundance; Amplification; Assembly; Cancer; Catalysis; Cell Line, Tumor; Cells (biology); Deoxyribonucleic acid; Differentiation; Dismantling; DNA; DNA - chemistry; DNA probes; Electrophoresis, Agar Gel; Entropy; Gain; Gold; gold nanoparticles; Humans; Imaging; Luminescence; microRNAs; MicroRNAs - chemistry; miRNA; molecular imaging; Nanoparticles; Nanostructure; Nucleic acids; Photoluminescence; Photons; Probes; Quantum Dots; Ribonucleic acid; RNA; Robustness; Sensitivity; microRNAs; quantum dots; catalysis; molecular imaging; gold nanoparticles
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201509726

Molecular imaging is an essential tool for disease diagnostics and treatment. Direct imaging of low‐abundance nucleic acids in living cells remains challenging because of the relatively low sensitivity and insufficient signal‐to‐background ratio of conventional molecular imaging probes. Herein, we report a class of DNA‐templated gold nanoparticle (GNP)–quantum dot (QD) assembly‐based probes for catalytic imaging of cancer‐related microRNAs (miRNA) in living cells with signal amplification capacity. We show that a single miRNA molecule could catalyze the disassembly of multiple QDs with the GNP through a DNA‐programmed thermodynamically driven entropy gain process, yielding significantly amplified QD photoluminescence (PL) for miRNA imaging. By combining the robust PL of QDs with the catalytic amplification strategy, three orders of magnitude improvement in detection sensitivity is achieved in comparison with non‐catalytic imaging probe, which enables facile and accurate differentiation between cancer cells and normal cells by miRNA imaging in living cells.
Break it up! High‐sensitivity molecular imaging of microRNA in living cells is realized by DNA‐programmed catalytic disassembly of gold nanoparticles and quantum dots (QDs).