• 文献标题:   Highly sensitive exonuclease III-assisted fluorometric determination of silver(I) based on graphene oxide and self-hybridization of cytosine-rich ss-DNA
  • 文献类型:   Article
  • 作  者:   LANG MJ, LI Q, HUANG HM, YU F, CHEN QH
  • 作者关键词:   quenching, fam label, fluorescence, dna probe, dna cleavage, selfhybridization, exonuclease
  • 出版物名称:   MICROCHIMICA ACTA
  • ISSN:   0026-3672 EI 1436-5073
  • 通讯作者地址:   Hubei Univ Med
  • 被引频次:   7
  • DOI:   10.1007/s00604-016-1795-6
  • 出版年:   2016

▎ 摘  要

We report on a method for selective fluorometric determination of Ag(I) based on the use of graphene oxide (GO) and by exploiting exonuclease III-assisted signal amplification. In the presence of Ag(I), the self-hybridization of cytosine-rich ss-DNA labeled with the fluorescent tag FAM leads to the formation of a ds-DNA that is cleaved by the catalytic action of Exo III. In the absence of Ag(I) ions, however, the tagged ss-DNA is adsorbed on the surface of GO and its fluorescence is quenched. As a result, the induction of the process by Ag(I) leads to a strong amplification of fluorescence. The method allows Ag(I) ions to be determined in the 1 to 250 nM concentration range, with a 0.1 nM detection limit. The recoveries range from 93.3 to 105.1 %, with RSDs of < 8.2 %.