title: Fe₃O₄@Ag magnetic nanoparticles for microRNA capture and duplex-specific nuclease signal amplification based SERS detection in cancer cells.
abstract: A functionalized Fe3O4@Ag magnetic nanoparticle (NP) biosensor for microRNA (miRNA) capture and ultrasensitive detection in total RNA extract from cancer cells was reported in this paper. Herein, Raman tags-DNA probes modified Fe3O4@Ag NPs were designed both as surface-enhanced Raman scattering (SERS) SERS and duplex-specific nuclease signal amplification (DSNSA) platform. Firstly, target miRNAs were captured to the surface of Fe3O4@Ag NPs through DNA/RNA hybridization. In the presence of endonuclease duplex specific nuclease (DSN), one target miRNA molecule could rehybrid thousands of DNA probes to trigger the signal-amplifying recycling. Base on the superparamagnetic of Fe3O4@Ag NPs, target miRNA let-7b can be captured, concentrated and direct quantified within a PE tube without any PCR preamplification treatment. The detection limit was 0.3fM (15 zeptomole, 50μL), nearly 3 orders of magnitude lower than conventional fluorescence based DSN biosensors for miRNA(∼100fM), even single-base difference between the let-7 family members can be discriminated. The result provides a novel proposal to combine the perfect single-base recognition and signal-amplifying ability of the endonuclease DSN with cost-effective SERS strategy for miRNA point-of-care (POC) clinical diagnostics.
authors.affiliation: Capital Medical University, Department of Toxicology, No. 10 Xitoutiao, You An Men, Beijing 100069, PR China; Beijing Institute of Radiation Medicine, Beijing Key Laboratory of New Molecular Diagnosis Techniques for Infectious Dedication, 27 Taiping Road, Beijing, PR China.
authors.forename: Yuanfeng
authors.initials: Y
authors.lastname: Pang
authors.affiliation: Beijing Institute of Radiation Medicine, Beijing Key Laboratory of New Molecular Diagnosis Techniques for Infectious Dedication, 27 Taiping Road, Beijing, PR China; College of Life Science &Bio-Engineering, Beijing University of Technology, Beijing 100124, PR China.
authors.forename: Chongwen
authors.initials: C
authors.lastname: Wang
authors.affiliation: Beijing Institute of Radiation Medicine, Beijing Key Laboratory of New Molecular Diagnosis Techniques for Infectious Dedication, 27 Taiping Road, Beijing, PR China; School of Pharmaceutical Science, Zhengzhou University, Zhengzhou 450001, PR China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.affiliation: Capital Medical University, Department of Toxicology, No. 10 Xitoutiao, You An Men, Beijing 100069, PR China. Electronic address: zwsun@ccmu.edu.cn.
authors.forename: Zhiwei
authors.initials: Z
authors.lastname: Sun
authors.affiliation: Beijing Institute of Radiation Medicine, Beijing Key Laboratory of New Molecular Diagnosis Techniques for Infectious Dedication, 27 Taiping Road, Beijing, PR China. Electronic address: Ruixiao203@sina.com.
authors.forename: Rui
authors.initials: R
authors.lastname: Xiao
authors.affiliation: Beijing Institute of Radiation Medicine, Beijing Key Laboratory of New Molecular Diagnosis Techniques for Infectious Dedication, 27 Taiping Road, Beijing, PR China.
authors.forename: Shengqi
authors.initials: S
authors.lastname: Wang
mesh_terms: D045744:Cell Line, Tumor; D006367:HeLa Cells; D006801:Humans; D058185:Magnetite Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D035683:MicroRNAs / Q000032:analysis* / Q000235:genetics / Q000302:isolation & purification; D009369:Neoplasms / Q000235:genetics; D021141:Nucleic Acid Amplification Techniques / Q000379:methods; D019095:Point-of-Care Systems; D012834:Silver / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000379:methods*
chemical_list: D058185:Magnetite Nanoparticles; D035683:MicroRNAs; C487931:mirnlet7 microRNA, human; D012834:Silver
keywords: Duplex-specific nuclease; Fe(3)O(4)@Ag; MiRNA; Paramagnetic; SERS