title: Metal ion-mediated assembly of DNA nanostructures for cascade fluorescence resonance energy transfer-based fingerprint analysis.
abstract: Contamination of heavy metal ions in an aquatic environment poses a serious threat to human health. More seriously, heavy metal ions are usually present in the environment in a mixture, and the synergetic toxicity of multiple heavy metal ions is revealed (Aragay et al. Chem. Rev. 2011, 111, 3433; Chu et al. Aquat. Toxicol. 2002, 61, 53). Unfortunately, most of the existing methods based on DNA sequences are focusing on the detection of one type of metal ions. Simple and multiplexed detection of multiple metal ions has been poorly investigated and remains challenging. Here, we re-engineered the DNA sequences for Pb(2+), Hg(2+), and Ag(+), through which the binding of multiple metal ions initiated the self-assembly of these DNA sequences. On the basis of our rationally designed multicolor fluorescent labeling of the DNA sequences, cascade fluorescence resonance energy transfer (FRET) occurred. As a result, a fingerprint fluorescent spectrum was produced to indicate the presence of a single type of metal ions or multiple metal ions. The major advantages of our cascade FRET fingerprint technology include the following: (1) the "mix and read" detection mode in homogeneous solution is simple without the need of complicated instruments; (2) only single excitation is required to provide the cascade FRET fingerprint spectrum; (3) multiplexed detection capability can be realized intuitively and sensitively.
authors.affiliation: Division of Physical Biology and Bioimaging Center, Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences , Shanghai, 201800, China.
authors.forename: Jiaoyun
authors.initials: J
authors.lastname: Xia
authors.forename: Meihua
authors.initials: M
authors.lastname: Lin
authors.forename: Xiaolei
authors.initials: X
authors.lastname: Zuo
authors.forename: Shao
authors.initials: S
authors.lastname: Su
authors.forename: Lianhui
authors.initials: L
authors.lastname: Wang
authors.forename: Wei
authors.initials: W
authors.lastname: Huang
authors.forename: Chunhai
authors.initials: C
authors.lastname: Fan
authors.forename: Qing
authors.initials: Q
authors.lastname: Huang
mesh_terms: D002232:Carbocyanines / Q000737:chemistry; D004247:DNA / Q000737:chemistry* / Q000378:metabolism; D031541:Fluorescence Resonance Energy Transfer / Q000295:instrumentation / Q000379:methods*; D005456:Fluorescent Dyes / Q000737:chemistry; D007854:Lead / Q000032:analysis; D008628:Mercury / Q000032:analysis; D008670:Metals / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D049329:Nanostructures / Q000737:chemistry*; D009690:Nucleic Acid Conformation; D012834:Silver / Q000032:analysis
chemical_list: D002232:Carbocyanines; D005456:Fluorescent Dyes; D008670:Metals; C085321:cyanine dye 5; D007854:Lead; D012834:Silver; D004247:DNA; D008628:Mercury