Development of a sensor to study the DNA conformation using molecular logic gates

Area of Science:

• Biophysics
• Molecular Biology
• Spectroscopy

Background:

• Fluorescence Resonance Energy Transfer (FRET) is a distance-dependent physical process.
• DNA conformation is sensitive to environmental factors like pH.
• Laser dyes Acriflavine and Rhodamine B are suitable FRET pairs.

Purpose of the Study:

• To investigate FRET efficiency between Acriflavine and Rhodamine B.
• To determine the influence of DNA presence and pH on FRET.
• To demonstrate molecular logic gates for DNA conformation analysis.

Main Methods:

• Utilizing Fluorescence Resonance Energy Transfer (FRET) spectroscopy.
• Experimenting with Acriflavine and Rhodamine B dye pair.
• Varying DNA concentration and solution pH.
• Analyzing energy transfer efficiency and spectral changes.

Main Results:

• FRET efficiency is significantly modulated by the presence of DNA.
• pH-dependent changes in DNA conformation (double-stranded to single-stranded/random coil) impact FRET.
• Observed changes in FRET efficiency correlate with DNA structural transitions.
• Successfully demonstrated XOR and OR molecular logic gate functionalities.

Conclusions:

• FRET is a sensitive probe for DNA conformation in solution.
• Molecular logic gates based on FRET can provide insights into DNA structural states.
• This approach offers a novel method for studying DNA behavior under varying conditions.