Chongqing Key Laboratory of Catalysis and New Environmental Materials, College of Environment and Resources, Chongqing Technology and Business University, Chongqing, 400067, China.
Institute of Materials, China Academy of Engineering Physics, Mianyang, 621908, Sichuan, China.
Mikrochim Acta. 2018 May 20;185(6):306. doi: 10.1007/s00604-018-2836-0.
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. Graphical abstract Schematic presentation of the recycling cleavage of hairpins by using a three-way DNA junction structure. It causes a release of fluorescently labeled DNA fragments and quenching of fluorescence. It was successfully applied to the simultaneous determination of Cu(II), Mg(II) and Pb(II) in spiked human serum.
一种基于 DNA 的荧光法被用来同时测定多种金属离子。它是基于使用三链 DNA 结构来循环切割发夹。三个包含结合区域和酶链（E-DNA）区域的 DNA 序列杂交形成三链 DNA 结构。DNA 序列末端的酶链区域与发夹环上的底物序列（S-DNA）结合，形成典型的 DNA 酶结构。在分析物金属离子存在下，形成的 DNA 酶结构切割发夹的环。这伴随着荧光标记的 DNA 片段的释放和荧光的猝灭。检测限分别为 Cu(II)为 35 pM，Mg(II)为 2 nM，Pb(II)为 8 pM。该方法成功地应用于加标人血清中这些离子的同时测定。示意图 利用三链 DNA 结构循环切割发夹的示意图。它导致荧光标记的 DNA 片段的释放和荧光的猝灭。它成功地应用于加标人血清中 Cu(II)、Mg(II)和 Pb(II)的同时测定。
