DNA Tetrahedron-Based MNAzyme for Sensitive Detection of microRNA with Elemental Tagging

• DOI: 10.1021/acsami.1c17234
• Publication Date: 2021-12-01T20:15:33Z
• Authors: Shaocheng Liu; Jingyi Wu; Man He; Beibei Chen; Qi Kang; Yan Xu; Xiao Yin; Bin Hu
• Keywords: MicroRNAs; Magnetic Phenomena; Materials Testing; Metal Nanoparticles; DNA, Catalytic; Gold; 02 engineering and technology; DNA Probes; 0210 nano-technology

Heterogeneous immunoassay based on magnetic separation is commonly used in inductively coupled plasma-mass spectrometry (ICP-MS)-based biomedical analysis with elemental labeling. However, the functionalized beads (MBs) often suffer from non-specific adsorption and random distribution of functional probes. To overcome these problems, DNA tetrahedron (DT)-functionalized MBs were designed further conjugated substrate modified Au NPs (Sub-AuNP). Based prepared MB-DT-AuNP probes, an MB-DT multicomponent nucleic acid enzyme (MNAzyme) system involving as tags was proposed for highly sensitive quantification miRNA-155 by ICP-MS. Target miRNA would trigger assembly MNAzyme, Sub-AuNP be cleaved probe, resulting a cyclic amplification. Single-stranded DNA-functionalized MB (MB-ssDNA)-AuNP probes well. Comparatively, amount grafted onto MB-ssDNA-AuNP higher than that Meanwhile, signal-to-noise ratio obtained using over MNAzyme system. Under optimal experimental conditions, limit detection target 1.15 pmol L-1, improved 23 times use The MB-DT-MNAzyme-ICP-MS method applied to serum samples, recoveries 86.7-94.6% obtained. This featured high sensitivity, good specificity, simple operation, showing great application potential analysis.