A catalytic cleavage strategy for fluorometric determination of Hg(II) based on the use of a Mg(II)-dependent split DNAzyme and hairpins conjugated to gold nanoparticles

作者：Yun, Wen^*; Li, Fukun; Liu, Xingyan; Li, Ning; Chen, Lin^*; Yang, Lizhu^*

来源：Microchimica Acta, 2018, 185(10): 457.

DOI：10.1007/s00604-018-2990-4

• AuNPs
• Split DNAzyme
• Amplification
• Enzyme-freedetection
• T-Hg(II)-T

A catalytic cleavage strategy was developed for the fluorometric determination of Hg(II). The method is based on the use of a Mg(II)-dependent split DNAzyme. Fluorophore labeled hairpins were conjugated to gold nanoparticles (AuNPs) upon which fluorescence is quenched. Thymine-Hg(II)-thymine (T-Hg(II)-T) interaction causes the two DNA sequences to form an entire enzyme-strand DNA (E-DNA). The E-DNA bind to the hairpins on the AuNPs to form a Mg(II)-dependent DNAzyme structure. The circular cleavage of hairpins results in a signal amplification and in the recovery of fluorescence. The assay has a limit of detection (LOD) as low as 80 pM of Hg(II). This LOD is comparable to those obtained with other amplification strategies. The method was successfully applied to the determination of Hg(II) in Chinese herbs (Atractylodes macrocephala Koidz).

• 出版日期2018-10
• 单位温州医科大学; 西南科技大学; 重庆工商大学