DNA fluorescence shift sensor: a rapid method for the detection of DNA hybridization using silver nanoclusters

Area of Science:

• Nanotechnology
• Biochemistry
• Molecular Biology

Background:

• DNA-templated silver nanoclusters (AgNC) are subnanometer fluorophores with excellent photostability and brightness.
• AgNCs are utilized in diagnostics, primarily for deoxyribonucleic acid (DNA) detection.
• Varying DNA sequences in AgNC integration can alter fluorescence spectra, enabling detection through hybridization-induced shifts.

Purpose of the Study:

• To develop and optimize a DNA fluorescence shift sensor for detecting synthetic forkhead box P3 (FOXP3) DNA.
• To enable specific detection of both single-stranded and double-stranded FOXP3 DNA targets.
• To leverage AgNC fluorescence shifting to overcome background intensity issues in fluorescent assays.

Main Methods:

• Utilized DNA-templated silver nanoclusters (AgNC) as a core component of the fluorescence shift sensor.
• Designed a sensor system involving hybridization of an AgNC-bound G-rich strand (G-rich) to the target DNA.
• Formation of a three-way DNA junction upon successful hybridization, triggering a fluorescence spectral shift.

Main Results:

• Achieved a distinct shift in fluorescence spectra upon hybridization of the sensor with synthetic FOXP3 DNA.
• Observed a significant increase in fluorescence intensity, correlating with successful target binding.
• Demonstrated the sensor's ability to detect both single-stranded and double-stranded synthetic FOXP3 targets.

Conclusions:

• The developed DNA fluorescence shift sensor provides a rapid and specific method for DNA detection.
• This approach effectively utilizes hybridization efficiency to induce a measurable fluorescence spectral shift.
• The AgNC-based sensor offers a promising alternative to conventional DNA detection techniques.