Quantitative detection of well-based DNA array using switchable lanthanide luminescence

: Karhunen U, Soikkeli M, Lahdenperä S, Soukka T

Publisher: ELSEVIER SCIENCE BV

: 2013

: Analytica Chimica Acta

: ANAL CHIM ACTA

: null

: 772

: null

: 87

: 92

: 6

: 0003-2670

DOI: https://doi.org/10.1016/j.aca.2013.02.029

: http://api.elsevier.com/content/abstract/scopus_id:84875581772

In this report a novel wash-free method for multiplexed DNA detection is demonstrated employing target specific probe pairs and switchable lanthanide luminescence technology on a solid-phase array. Four oligonucleotide capture probes, conjugated at 3' to non-luminescent lanthanide ion carrier chelate, were immobilized as a small array on the bottom of a microtiter plate well onto which a mix of corresponding detection probes, conjugated at 5' to a light absorbing antenna ligand, were added. In the presence of complementary target nucleic acid both the spotted capture probe and the liquid-phase detection probe hybridize adjacently on the target. Consequently the two non-luminescent label molecules self-assemble and form a luminescent mixed lanthanide chelate complex. Lanthanide luminescence is thereafter measured without a wash step from the spots by scanning in time-resolved mode. The homogeneous solid-phase array-based method resulted in quantitative detection of synthetic target oligonucleotides with 0.32. nM and 0.60. nM detection limits in a single target and multiplexed assay, respectively, corresponding to 3× SD of the background. Also qualitative detection of PCR-amplified target from Escherichia coli is described. © 2013 Elsevier B.V.