title: Target triggered self-assembly of Au nanoparticles for amplified detection of Bacillus thuringiensis transgenic sequence using SERS.
abstract: The research methods for DNA detection have been widely extended since the application of nanotechnology, but it remains a challenge to detect specific DNA sequences or low abundance genes in the biological samples with accuracy and sensitivity. Here we developed a SERS biosensing platform by target DNA (tDNA) triggered self-assembly of Au nanoparticles (Au NPs) probes on DNA nanowires for signal amplification in DNA analysis. Based on the hybridization chain reactions (HCR) and surface enhanced Raman scattering (SERS) technology, the SERS intensity reveals a good linearity with tDNA ranging from 50 pM to 500 pM under optimal conditions. The specific detection of tDNA sequence was realized with a detection limit of 50 pM (S/N=3). To demonstrate the specificity and universality of the strategy, the single-base mismatches in DNA and the Bacillus thuringiensis (Bt) transgenic sequence were successively applied in the SERS assay. The results showed that the sensitivity and accuracy of the SERS-based assay were comparable with real-time PCR. Besides, the method would provide precise and ultra-sensitive detection of tDNA but also informative supplement to the SERS biosensing platform.
authors.affiliation: College of Science, State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, PR China.
authors.forename: Kun
authors.initials: K
authors.lastname: Chen
authors.affiliation: College of Science, State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, PR China.
authors.forename: Long
authors.initials: L
authors.lastname: Wu
authors.affiliation: College of Science, State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, PR China.
authors.forename: Xiaochun
authors.initials: X
authors.lastname: Jiang
authors.affiliation: College of Science, State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, PR China.
authors.forename: Zhicheng
authors.initials: Z
authors.lastname: Lu
authors.affiliation: College of Science, State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, PR China.
authors.forename: Heyou
authors.initials: H
authors.lastname: Han
mesh_terms: D001413:Bacillus thuringiensis / Q000235:genetics*; D020137:Base Pair Mismatch; D015374:Biosensing Techniques / Q000379:methods*; D004269:DNA, Bacterial / Q000235:genetics; D004274:DNA, Recombinant / Q000235:genetics; D005798:Genes, Bacterial; D006046:Gold; D053768:Metal Nanoparticles; D036103:Nanotechnology; D053770:Nanowires; D060888:Real-Time Polymerase Chain Reaction; D013059:Spectrum Analysis, Raman / Q000379:methods*
chemical_list: D004269:DNA, Bacterial; D004274:DNA, Recombinant; D006046:Gold
keywords: Au nanoparticles; Bacillus thuringiensis transgene; DNA biosensors; Hybridization chain reactions; Surface enhanced Raman scattering