These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Detection of lead (II) with a "turn-on" fluorescent biosensor based on energy transfer from CdSe/ZnS quantum dots to graphene oxide.
    Author: Li M, Zhou X, Guo S, Wu N.
    Journal: Biosens Bioelectron; 2013 May 15; 43():69-74. PubMed ID: 23277342.
    Abstract:
    Graphene oxide (GO) sheets are mixed with the aptamer-functionalized CdSe/ZnS quantum dots (QDs). Consequently, the aptamer-conjugated QDs bind to the GO sheets to form a GO/aptamer-QD ensemble, which enables the energy transfer from the QDs to the GO sheets, quenching the fluorescence of QDs. The GO/aptamer-QD ensemble assay acts as a "turn-on" fluorescent sensor for Pb(2+) detection. When Pb(2+) ions are present in the assay, the interaction of Pb(2+) with the aptamer induces a conformational change in the aptamer, leading to the formation of a G-quadruplex/Pb(2+) complex. As a result, the QDs that are linked to the G-quadruplex/Pb(2+) complex are detached from the GO sheet, which "turns on" the fluorescence of the QDs. This sensor exhibits a limit of detection of 90pM and excellent selectivity toward Pb(2+) over a wide range of metal ions. The experiments have provided direct evidence that the fluorescence of QDs is quenched by GO via the nano-metal surface energy transfer (NSET) mechanism rather than the conventional Förster resonance energy transfer (FRET) process.
    [Abstract] [Full Text] [Related] [New Search]