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A functionalized THz sensor for marker-free DNA analysis.

M Nagel·F Richter·P Haring-Bolívar·H Kurz
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Abstract

We report on a novel resonant THz sensor for the label-free analysis of DNA molecules. The sensor allows the direct detection of DNA-probe molecules at functionalized electrodes via hybridization. Subsequent time resolved photoconductive sampling of the THz transmission identifies the binding state between probe and target DNA. Integrating neighbouring sensors on a chip, this technique can be extended to a parallel analysis of multiple DNA sequences. A clearly readable sensor response is obtained with less then 40 fmol of 20-mer single-stranded DNA molecules, indicating at least a sevenfold sensitivity increase compared to previous approaches.

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Biosensing TechniquesDNA ProbesElectrodesNucleic Acid HybridizationSensitivity and SpecificitySpectrum AnalysisJournal Article

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M Nagel, F Richter, P Haring-Bolívar, H Kurz. 2003-11-21. A functionalized THz sensor for marker-free DNA analysis.. https://doi.org/10.1088/0031-9155%2F48%2F22%2F001

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