Au@Ag core-shell nanoparticles for microRNA-21 determination based on duplex-specific nuclease signal amplification and surface-enhanced Raman scattering.
A novel surface-enhanced Raman scattering (SERS) analysis strategy has been designed combining Au@DTNB@Ag core-shell nanoparticles (DTNB attachment on gold nanoparticles, then encapsulated in Ag shell nanoparticles named as ADANPs) and duplex-specific nuclease signal amplification (DSNSA) platform. Firstly, ADANPs and magnetic substrate of Fe3O4 nanoparticles were covalently attached to the 3'- and 5'- end of capture probe (CP) targeting miRNA-21. Upon the addition of target miRNA-21, these heteroduplexes were specifically cleaved by DSN and resulted in ADANPs that were released from the surface of Fe3O4 nanoparticles (Fe3O4 NPs). At the same time, miRNA-21 remained intact and can rehybridize another DNA probe to trigger the signal-amplifying reaction. Based on this principle, the developed SERS method exhibited good linearity in the range 0 to 1 nM for miRNA-21 with a limit of detection (LOD) of 0.084 fM and has an ability to differentiate even a single-base mismatched sequence on the target sequence or other miRNA sequence. The results provide a novel SERS method which can successfully been applied to the miRNA-21 detection in human serum. Graphical abstract a shows the synthesis of Fe3O4 NPs and the conjugation of Au@DTNB@Ag NPs (ADANPs) for the detection of miRNA-21, b shows the operating principle of DSN-assisted signal amplification strategy for miRNA detection based on Fe3O4@CP@ADA NPs.
['Xu|Wei|W|', 'Zhao|Aiwu|A|0000-0001-6901-0512', 'Zuo|Fangtao|F|', 'Khan|Ranjha|R|', 'Hussain|Hafiz Muhammad Jafar|HMJ|', 'Chang|Jianguo|J|']
D001483:Base Sequence D045744:Cell Line, Tumor D004247:DNA D004228:Dithionitrobenzoic Acid D004720:Endonucleases D006046:Gold D006801:Humans D061925:Immobilized Nucleic Acids D057230:Limit of Detection D058185:Magnetite Nanoparticles D035683:MicroRNAs D009693:Nucleic Acid Hybridization D015203:Reproducibility of Results D012680:Sensitivity and Specificity D012834:Silver D013059:Spectrum Analysis, Raman
Duplex-specific nuclease Surface-enhanced Raman scattering Au@DTNB@Ag core-shell nanoparticles miRNA-21 Human serum