Thoas Fioretos
Research team manager
Sub-Nanomolar Detection of Oligonucleotides Using Molecular Beacons Immobilized on Lightguiding Nanowires
Author
Summary, in English
The detection of oligonucleotides is a central step in many biomedical investigations. The most commonly used methods for detecting oligonucleotides often require concentration and amplification before detection. Therefore, developing detection methods with a direct read-out would be beneficial. Although commonly used for the detection of amplified oligonucleotides, fluorescent molecular beacons have been proposed for such direct detection. However, the reported limits of detection using molecular beacons are relatively high, ranging from 100 nM to a few µM, primarily limited by the beacon fluorescence background. In this study, we enhanced the relative signal contrast between hybridized and non-hybridized states of the beacons by immobilizing them on lightguiding nanowires. Upon hybridization to a complementary oligonucleotide, the fluorescence from the surface-bound beacon becomes coupled in the lightguiding nanowire core and is re-emitted at the nanowire tip in a narrower cone of light compared with the standard 4π emission. Prior knowledge of the nanowire positions allows for the continuous monitoring of fluorescence signals from each nanowire, which effectively facilitates the discrimination of signals arising from hybridization events against background signals. This resulted in improved signal-to-background and signal-to-noise ratios, which allowed for the direct detection of oligonucleotides at a concentration as low as 0.1 nM.
Department/s
- LU Profile Area: Light and Materials
- LTH Profile Area: Nanoscience and Semiconductor Technology
- LTH Profile Area: Engineering Health
- NanoLund: Centre for Nanoscience
- Solid State Physics
- Division of Molecular Hematology (DMH)
- LUCC: Lund University Cancer Centre
- Translational Genomic and Functional Studies of Leukemia
- Division of Clinical Genetics
Publishing year
2024
Language
English
Publication/Series
Nanomaterials
Volume
14
Issue
5
Document type
Journal article
Publisher
MDPI AG
Topic
- Analytical Chemistry
Keywords
- lightguiding
- limit of detection
- molecular beacons
- nanowires
- oligonucleotides
Status
Published
Research group
- Translational Genomic and Functional Studies of Leukemia
ISBN/ISSN/Other
- ISSN: 2079-4991