Time-resolved total internal reflection fluorescence study on hybridization of complementary single-stranded DNAs at...

Area of Science:

• Biophysical Chemistry
• Interface Science
• Molecular Biology

Background:

• DNA hybridization is fundamental to molecular biology.
• Controlling DNA hybridization at interfaces is crucial for applications like biosensing and nanotechnology.
• Understanding the factors influencing DNA assembly at liquid-liquid interfaces is an ongoing research area.

Purpose of the Study:

• To investigate the hybridization of complementary single-stranded DNAs (ssDNA) at a water/carbon tetrachloride (CCl4) interface.
• To determine the role of octadecylamine (ODA) in facilitating DNA hybridization at this interface.
• To elucidate the structural characteristics of the formed double-stranded DNA (dsDNA) and the mechanism of ODA's involvement.

Main Methods:

• Picosecond total internal reflection fluorescence spectroscopy was employed to monitor hybridization dynamics.
• Ethidium bromide was used as a fluorescent probe to assess DNA structure and hybridization.
• Experiments were conducted at the water/CCl4 interface with and without ODA in the oil phase.

Main Results:

• Complementary ssDNA successfully hybridized to form dsDNA at the water/CCl4 interface when ODA was present in the oil phase.
• Hybridization of ssDNA did not occur within the bulk water phase under the experimental conditions.
• Fluorescence dynamics indicated distinct structural changes associated with DNA hybridization at the interface.

Conclusions:

• Octadecylamine (ODA) plays a critical role in promoting and stabilizing DNA hybridization at the water/CCl4 interface.
• The water/CCl4 interface, in conjunction with ODA, provides a suitable environment for ssDNA to dsDNA conversion.
• The findings offer insights into interfacial molecular assembly and have implications for designing interfacial DNA-based systems.