Molecular-beacon-based array for sensitive DNA analysis.

Gang Yao; Weihong Tan

doi:10.1016/j.ab.2003.12.005

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Molecular-beacon-based array for sensitive DNA analysis.

Gang Yao·Weihong Tan

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Abstract

Molecular beacon (MB) DNA probes provide a new way for sensitive label-free DNA/protein detection in homogeneous solution and biosensor development. However, a relatively low fluorescence enhancement after the hybridization of the surface-immobilized MB hinders its effective biotechnological applications. We have designed new molecular beacon probes to enable a larger separation between the surface and the surface-bound MBs. Using these MB probes, we have developed a DNA array on avidin-coated cover slips and have improved analytical sensitivity. A home-built wide-field optical setup was used for imaging the array. Our results show that linker length, pH, and ionic strength have obvious effects on the performance of the surface-bound MBs. The fluorescence enhancement of the new MBs after hybridization has been increased from 2 to 5.5. The MB-based DNA array could be used for DNA detection with high sensitivity, enabling simultaneous multiple-target bioanalysis in a variety of biotechnological applications.

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Base Sequence DNA Primers DNA Probes Nucleic Acid Hybridization Oligonucleotide Array Sequence Analysis Sensitivity and Specificity Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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Gang Yao, Weihong Tan. 2004-08-15. Molecular-beacon-based array for sensitive DNA analysis.. https://doi.org/10.1016/j.ab.2003.12.005

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