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Updated: Jun 9, 2026
10:16
Production and Targeting of Monovalent Quantum Dots
Published on: October 23, 2014
Direct in situ hybridization with oligonucleotide functionalized quantum dot probes
1University of Chemistry and Biochemistry, California NanoSystems Institute, University of California at Los Angeles, Los Angeles, CA, USA. lbento@chem.ucla.edu
Methods in Molecular Biology (Clifton, N.J.)
|September 3, 2010
Summary
Quantum dots (QDs) offer superior fluorescent probes for biological imaging. This study details a rapid assay using QD-based FISH probes for simultaneous multicolor imaging of genetic sequences in nuclei and chromosomes.
Area of Science:
- Material Science
- Biotechnology
- Genetics
Background:
- Fluorescent semiconductor nanocrystals, or quantum dots (QDs), are advanced fluorescent probes.
- QDs offer advantages over organic dyes, including higher brightness and photostability.
- QDs enable simplified multicolor detection in biological imaging.
Purpose of the Study:
- To describe a rapid assay for direct imaging of multiple repetitive subnuclear genetic sequences.
- To utilize quantum dot (QD)-based fluorescent in situ hybridization (FISH) probes.
- To demonstrate simultaneous multicolor imaging of genetic sequences.
Main Methods:
- Functionalizing streptavidin-coated QDs (SAvQDs) with biotinylated oligonucleotides.
- Employing a single hybridization/detection step for QD-FISH probes.
- Utilizing the broad absorption spectra of QDs for multicolor imaging with a single laser.
Main Results:
- QD-FISH probes successfully penetrate intact interphase nuclei and metaphase chromosomes.
- Probes show effective targeting of dense chromatin domains.
- Simultaneous imaging of two distinct QD-FISH probes was achieved using a single laser excitation wavelength.
Conclusions:
- The QD-FISH method provides a rapid and flexible alternative for multicolor cytogenetic applications.
- The assay requires minimal custom conjugation and is easily expandable.
- This technique enhances flexibility in FISH applications for repetitive DNAs.
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