In vitro selection and application of lanthanide-dependent DNAzymes

Po-Jung Jimmy Huang; Juewen Liu

doi:10.1016/bs.mie.2021.01.013

In vitro selection and application of lanthanide-dependent DNAzymes

Methods Enzymol. 2021:651:373-396. doi: 10.1016/bs.mie.2021.01.013. Epub 2021 Mar 11.

Authors

Po-Jung Jimmy Huang¹, Juewen Liu²

Affiliations

¹ Department of Chemistry, Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, ON, Canada.
² Department of Chemistry, Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, ON, Canada. Electronic address: liujw@uwaterloo.ca.

PMID: 33888210
DOI: 10.1016/bs.mie.2021.01.013

Abstract

Highly sensitive and selective detection of lanthanide ions is a major analytical challenge. In recent years, the use of DNA for this purpose has been pursued. For such highly charged cations, it is difficult to select their aptamers due to strong nonspecific binding. On the other hand, the use of catalytic DNA or DNAzymes has an advantage to overcome this problem, especially DNAzymes with RNA-cleaving activity. In this chapter, a few such DNAzymes are introduced and methods for in vitro selection of lanthanide-dependent RNA-cleaving DNAzymes are described in detail, including the selection protocols, the DNA sequences used, the characterization of selected DNAzymes and their conversion into biosensors. All of the experiments use only fluorophore-labeled DNA, and radioisotope labeling is completely avoided. The resulting DNAzymes can distinguish lanthanides from non-lanthanide metals, tell the difference between light and heavy lanthanides, and can be used together to discriminate individual lanthanides.

Keywords: Aptamers; Biosensors; Deoxyribozymes; Metal ions; RNA cleavage.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Biosensing Techniques*
DNA, Catalytic*
Ions
Lanthanoid Series Elements*
RNA

Substances

DNA, Catalytic
Ions
Lanthanoid Series Elements
RNA