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Updated: Jul 8, 2026
10:01
The Visual Colorimetric Detection of Multi-nucleotide Polymorphisms on a Pneumatic Droplet Manipulation Platform
Published on: September 27, 2016
Imaging gold nanoparticles for DNA sequence recognition in biomedical applications.
Peter Eaton1, Gonçalo Doria, Eulalia Pereira
1REQUIMTE, Departamento de Química, Faculdade de Ciências da Universidade do Porto, Portugal. peter.eaton@fc.up.pt
IEEE Transactions on Nanobioscience
|January 26, 2008
Summary
Gold nanoparticles (Au nanoprobes) with DNA probes were observed binding to DNA targets using atomic force microscopy (AFM). This confirms a new method for detecting specific DNA sequences through nanoparticle interactions.
Area of Science:
- Nanotechnology
- Molecular Biology
- Biophysics
Background:
- Gold nanoparticles (Au nanoprobes) functionalized with oligonucleotides are used for DNA detection.
- Specific hybridization between Au nanoprobes and DNA targets is crucial for assay development.
- Understanding the structural basis of this interaction is key to optimizing detection assays.
Purpose of the Study:
- To directly visualize and characterize the hybridization of oligonucleotide-derivatized gold nanoparticles (Au nanoprobes) with DNA targets.
- To provide molecular-level evidence for the specific binding mechanism of Au nanoprobes to DNA sequences.
- To investigate the structural consequences of Au nanoprobe hybridization with different DNA target lengths.
Main Methods:
- Direct observation of hybridization using Atomic Force Microscopy (AFM).
- Utilizing salt-induced aggregation as a control for nanoparticle interaction.
- Employing both linearized plasmid DNA and PCR-amplified fragments as DNA targets.
Main Results:
- AFM directly visualized the hybridization of Au nanoprobes with double-stranded DNA.
- Complex structures formed with long DNA targets, enhancing stability against salt-induced aggregation.
- For shorter DNA targets, hybridization occurred at the specific sequence location, confirming targeted binding.
Conclusions:
- The study provides direct molecular-level evidence of specific hybridization between Au nanoprobes and target DNA sequences.
- Observed structures confirm the mechanism of Au nanoprobe binding to DNA.
- The findings support the development of Au nanoprobe-based homogeneous assays for DNA sequence detection.
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01:20Immunogold Electron Microscopy
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03:31Labeling DNA Probes
DNA probes are fragments of DNA labeled with a reporter tag to enable their detection or purification. The resulting labeled DNA probes can then hybridize to target nucleic acid sequences through complementary base-pairing, and may be used to recover or identify these regions.
Radioisotopes, fluorophores, or small molecule binding partners like biotin or digoxigenin, are the most widely used reporter tags for labeling DNA probes. These labels can be attached to the probe DNA molecule via...
Radioisotopes, fluorophores, or small molecule binding partners like biotin or digoxigenin, are the most widely used reporter tags for labeling DNA probes. These labels can be attached to the probe DNA molecule via...