Ultrasensitive DNAzyme Beacon for Lanthanides and Metal Speciation

详细信息    查看全文

• 作者：Po-Jung Jimmy Huang ; Jenny Lin ; Jing Cao ; Mahsa Vazin ; Juewen Liu
• 刊名：Analytical Chemistry
• 出版年：2014
• 出版时间：February 4, 2014
• 年：2014
• 卷：86
• 期：3
• 页码：1816-1821
• 全文大小：365K
• ISSN：1520-6882

文摘

Metal-ion detection and speciation analysis is crucial for environmental monitoring. Despite the importance of lanthanides, few sensors are available for their detection. DNAzymes have been previously used to detect divalent metals, while no analytical work was carried out for trivalent and tetravalent ions. Herein, in vitro selection was performed using a Ce⁴⁺ salt as the target metal, and a new DNAzyme (named Ce13) with a bulged hairpin structure was isolated and characterized. Interestingly, Ce13 has almost no activity with Ce⁴⁺ but is highly active with all trivalent lanthanides and Y³⁺, serving as a general probe for rare earth metals (omitting Sc). A DNAzyme beacon was engineered detecting down to 1.7 nM Ce³⁺ (240 parts per trillion), and other lanthanides showed similar sensitivity. The feasibility of metal speciation analysis was demonstrated by measuring the reduction of Ce⁴⁺ to Ce³⁺.