title: Gold nanoparticles with asymmetric polymerase chain reaction for colorimetric detection of DNA sequence.
abstract: We developed a novel strategy for rapid colorimetric analysis of a specific DNA sequence by combining gold nanoparticles (AuNPs) with an asymmetric polymerase chain reaction (As-PCR). In the presence of the correct DNA template, the bound oligonucleotides on the surface of AuNPs selectively hybridized to form complementary sequences of single-stranded DNA (ssDNA) target generated from As-PCR. DNA hybridization resulted in self-assembly and aggregation of AuNPs, and a concomitant color change from ruby red to blue-purple occurred. This approach is simpler than previous methods, as it requires a simple mixture of the asymmetric PCR product with gold colloid conjugates. Thus, it is a convenient colorimetric method for specific nucleic acid sequence analysis with high specificity and sensitivity. Most importantly, the marked color change occurs at a picogram detection level after standing for several minutes at room temperature. Linear amplification minimizes the potential risk of PCR product cross-contamination. The efficiency to detect Bacillus anthracis in clinical samples clearly indicates the practical applicability of this approach.
authors.affiliation: CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology of China, Beijing 100190, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Deng
authors.forename: Yi
authors.initials: Y
authors.lastname: Xu
authors.forename: Yanhua
authors.initials: Y
authors.lastname: Liu
authors.forename: Zhijun
authors.initials: Z
authors.lastname: Che
authors.forename: Huilin
authors.initials: H
authors.lastname: Guo
authors.forename: Shuxian
authors.initials: S
authors.lastname: Shan
authors.forename: Yun
authors.initials: Y
authors.lastname: Sun
authors.forename: Xiaofang
authors.initials: X
authors.lastname: Liu
authors.forename: Keyang
authors.initials: K
authors.lastname: Huang
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Ma
authors.forename: Yan
authors.initials: Y
authors.lastname: Wu
authors.forename: Xing-Jie
authors.initials: XJ
authors.lastname: Liang
mesh_terms: D001408:Bacillus anthracis / Q000235:genetics; D001483:Base Sequence; D003124:Colorimetry; D004247:DNA / Q000737:chemistry* / Q000378:metabolism; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D009841:Oligonucleotides / Q000737:chemistry; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA / Q000379:methods*
chemical_list: D009841:Oligonucleotides; D006046:Gold; D004247:DNA