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Aptamer-based ATP assay using a luminescent light switching complex.

Jun Wang·Yaxin Jiang·Cuisong Zhou·Xiaohong Fang
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Abstract

With the increasing applications of nucleic acid aptamers as a new class of molecular recognition probes in bioanalysis and biosensor development, the development of general and simple signaling strategies to transduce aptamer-target binding events to detectable signals is demanding. We have developed a new signaling method based on aptamers and a DNA molecular light switching complex, [Ru(phen)2(dppz)]2+, for sensitive protein detection. In this work, we have demonstrated the applicability of this signaling mechanism to small-molecule detection using ATP as a model target. Our results have shown that upon ATP binding to the folded aptamer where [Ru(phen)2(dppz)]2+ intercalated, the conformational change or distortion of the aptamer is large enough to cause a significant luminescence change of [Ru(phen)2(dppz)]2+. By monitoring the ATP-dependent luminescence intensity change, we have achieved ATP detection with high selectivity and high sensitivity down to 1 nM in homogeneous solution. The method is very simple without the needs for covalently labeling aptamers or using costly enzymes and multistep analysis as other reported fluorescence/luminescence assays for ATP. The successful detection of ATP indicates that using the signaling aptamers with [Ru(phen)2(dppz)]2+ is expected to be a general method for aptamer-based target detection.

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Adenosine TriphosphateAptamers, NucleotideLightLuminescent AgentsLuminescent MeasurementsMolecular ConformationOrganometallic CompoundsOsmolar ConcentrationSensitivity and SpecificitySolutionsStructure-Activity RelationshipJournal ArticleResearch Support, Non-U.S. Gov't

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Jun Wang, Yaxin Jiang, Cuisong Zhou, Xiaohong Fang. 2005-06-01. Aptamer-based ATP assay using a luminescent light switching complex.. https://doi.org/10.1021/ac050165w

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