Colorimetric allele analysis based on the DNA-directed cooperative formation of luminous lanthanide complexes

Abstract

We present the facile technique of colorimetric SNP analysis through DNA-templated cooperative complexation between a luminescent lanthanide ion (Ln(3+): Tb(3+) or Eu(3+)) and two ODN (oligodeoxyribonucleotide) conjugates carrying a metal chelator. Ethylenediaminetetraacetic acid (EDTA) and 1,10-phenanthrorine (phen) were covalently attached to ODNs to form the conjugate probes, capture and sensitizer probes, respectively. The sequences of the conjugates were designed so as to form a tandem duplex with a target with their auxiliary units facing each other, providing a microenvironment to accommodate Ln(3+). The capture probes for the wild-type (wt) and the mutant (mut) of thiopurine S-methyltransferase gene, were mixed with equimolar amounts of Tb(3+) and Eu(3+), respectively. Then both of the allele specific capture probe solutions and the sensitizer probe were added to three different solutions containing the targets, wt/wt (G/G), mut/mut (C/C), and wt/mut (G/C). The solutions emitted in green, red, and yellow, respectively; the colors were identified even by the naked eye.

Toward Non-Enzymatic Ultrasensitive Identification of Single Nucleotide Polymorphisms by Optical Methods

“…Using this novel design of the multicomponent DNAzyme-based sensor system, authors were able to detect various viral, bacterial, cellular DNA and RNA. ) attached to allele-specific capture probes was demonstrated to be a useful tool in colorimetric SNP sensing of G/C mismatch in the thiopurine S-methyltransferase (TPMT) gene [60]. In doing this, 7mer capture probes, Cwt7 and Cmut7, complementary to wild-type and the mutant part of the target gene, respectively, and carrying EDTA at the 5' terminus, were prepared.…”

“…As illustrated below, several non-enzymatic techniques provide advantages of improved repeatability, decreased cost and robustness. Based on the chemical nature of the utilized probe, these techniques can be divided into three groups: methods applying nano-and magnetic-particles , (1) aptamer-and protein-based assays [47][48][49][50][51][52], (2) and other techniques utilizing bright chemically modified nucleic acid analogues [53][54][55][56][57][58][59][60]…”

A polymorphic lanthanide complex as selective Co2+ sensor and luminescent timer

“…Some organic molecules, silver and gold oxide nanoparticles were applied to detect Co 2+ [26][27][28][29][30], and a lanthanide show sensing effect to Zn 2+ , Cd 2+ and Co 2+ at the same time, but it is not a selective Co 2+ sensor [27]. That is, though lanthanide complex had been reported to detect many kinds of ions and molecules [1,3,[31][32][33][34][35][36][37][38][39][40], due to its unique photophysical properties (such as microsecond to millisecond lifetimes, characteristic and narrow emission bands, as well as large Stokes shifts), the selective sensing to Co 2+ is not reported. Therefore, selective and sensitive sensing Co 2+ by luminescent lanthanide complex is urgent and interesting.…”

Template-directed formation of luminescent lanthanide complexes: Versatile tools for colorimetric identification of single nucleotide polymorphism

“…That is, it provides more quality signals than that expected from the system focusing on a one-onone interaction between the targets and probes. In these several years, we have been engaged in the development of gene detection with a smart manner through the cooperative action between the probes [13,23,[34][35][36][37][38][39]. In a series of studies, we showed that the hybridization of ODN (oligodeoxyribonucleotide) conjugates 0162-0134/$ -see front matter Ó 2008 Elsevier Inc. All rights reserved.…”

“…doi:10.1016/j.jinorgbio.2008.06.016 bearing a metal chelator on their terminus was efficiently controlled by a metal ion as an allosteric effector. This work suggested that the general concept of ''metal ion-directed cooperative recognition" could be applied to the split-probing of specific genes by employing luminescent lanthanides as the metal ion [34][35][36][37]. Metal-centered luminescence from the complexes of the trivalent lanthanide ions (Ln(III)) have been widely exploited in bioassays.…”