Three-way DNA junction based platform for ultra-sensitive fluorometric detection of multiple metal ions as exemplified for Cu(II), Mg(II) and Pb(II)
- 205 Downloads
A DNA-based fluorometric method is described for simultaneous determination of multiple metal ions. It is based on recycling cleavage of hairpins by using a three-way DNA junction structure. Three DNA sequences containing a binding region and an enzyme-strand (E-DNA) region are hybridized to form a three-way DNA junction. The enzyme strand regions at the end of the DNA sequence binds to the substrate sequence (S-DNA) at the loop of the hairpin to form typical DNAzyme structures. In the presence of analyte metal ions, the DNAzyme structure thus formed cleaves the loop of hairpins. This is accompanied by a release of fluorescently labeled DNA fragments and by quenching of fluorescence. The detection limits are 35 pM for Cu(II), 2 nM for Mg(II), and 8 pM for Pb(II). This method was successfully applied to the simultaneous determination of these ions in spiked human serum.
KeywordsRecycling cleavage Graphene oxide DNAzyme Amplification Fluorescence Hairpin
This work is sponsored by Chongqing Key Laboratory of Catalysis and New Environmental Materials (Grant No. KFJJ2017033).
Compliance with ethical standards
The author(s) declare that they have no competing interests.
- 2.Anastassopoulou J, Theophanides T (1995) The role of metal ions in biological systems and medicine. In: Kessissoglou DP (ed) Bioinorganic chemistry. NATO ASI Series (Series C: Mathematical and Physical Sciences), vol 459. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-0255-1_17
- 3.Neilands J (1973) Metal ions in biological systems: studies of some biochemical and environmental problems. Plenum Press, New YorkGoogle Scholar
- 14.Yang J, Dou B, Yuan R, Xiang Y (2016) Proximity binding and metal ion-dependent DNAzyme cyclic amplification-integrated Aptasensor for label-free and sensitive electrochemical detection of thrombin. Anal Chem 88(16):8218–8223. https://doi.org/10.1021/acs.analchem.6b02035 CrossRefPubMedGoogle Scholar