Imaging DNA single-strand breaks generated by reactive oxygen species using a liquid crystal-based sensor

Area of Science:

• Biochemistry
• Materials Science
• Chemical Sensing

Background:

• DNA single-strand breaks (SSBs) are linked to aging and cancer.
• Detecting SSBs is crucial for understanding DNA damage and disease.
• Existing methods for SSB detection can be complex and time-consuming.

Purpose of the Study:

• To develop a novel, simple sensor for detecting DNA single-strand breaks (SSBs).
• To utilize liquid crystals (LCs) for visualizing the impact of reactive oxygen species (ROS) on DNA.
• To provide a rapid and effective method for assessing DNA damage.

Main Methods:

• A liquid crystal (LC)-based sensor was designed using cationic surfactants.
• The sensor detects changes in LC orientation caused by ssDNA adsorption and SSB formation.
• DNA damage was induced using reactive oxygen species (ROS) from the Fenton reaction.
• Optical changes in LC alignment under polarized light microscopy were observed.

Main Results:

• Single-stranded DNA (ssDNA) adsorption induced planar orientation of LCs.
• DNA single-strand breaks (SSBs) disrupted ssDNA-surfactant interactions, leading to homeotropic LC alignment.
• A clear optical shift from bright to dark was observed, indicating SSB presence.
• The sensor demonstrated effective and rapid detection of DNA damage.

Conclusions:

• A novel liquid crystal (LC) sensor effectively detects DNA single-strand breaks (SSBs).
• This method provides a simple, rapid, and instrument-free approach for DNA damage detection.
• The findings offer new insights into DNA damage mechanisms and sensing strategies.