title: Sensitive detection of miRNA by using hybridization chain reaction coupled with positively charged gold nanoparticles.
abstract: Positively charged gold nanoparticles (+)AuNPs can adsorb onto the negatively charged surface of single-stranded DNA (ssDNA) or double-stranded DNA (dsDNA). Herein, long-range dsDNA polymers could form based on the hybridization chain reaction (HCR) of two hairpin probes (H1 and H2) by using miRNA-21 as an initiator. (+)AuNPs could adsorb onto the negatively charged surface of such long-range dsDNA polymers based on the electrostatic adsorption, which directly resulted in the precipitation of (+)AuNPs and the decrease of (+)AuNPs absorption spectra. Under optimal conditions, miRNA-21 detection could be realized in the range of 20 pM-10 nM with a detection limit of 6.8 pM. In addition, (+)AuNPs used here are much more stable than commonly used negatively charged gold nanoparticles ((-)AuNPs) in mixed solution that contained salt, protein or other metal ions. Importantly, the assay could realize the detection of miRNA in human serum samples.
authors: School of Life Science, Jiangsu Normal University, Xuzhou 221116, PR China.
authors: Xiangmin
authors: X
authors: Miao
authors: KeWen College, JiangSu Normal University, Xuzhou 221116, PR China.
authors: Xue
authors: X
authors: Ning
authors: School of Life Science, Jiangsu Normal University, Xuzhou 221116, PR China.
authors: Zongbing
authors: Z
authors: Li
authors: School of Life Science, Jiangsu Normal University, Xuzhou 221116, PR China.
authors: Zhiyuan
authors: Z
authors: Cheng
mesh_terms: D004247:DNA / Q000737:chemistry*; D004277:DNA, Single-Stranded / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D006801:Humans; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry; D035683:MicroRNAs / Q000097:blood / Q000235:genetics / Q000302:isolation & purification*; D009693:Nucleic Acid Hybridization
chemical_list: D004277:DNA, Single-Stranded; D035683:MicroRNAs; D006046:Gold; D004247:DNA