A Thioflavin T-induced G-Quadruplex Fluorescent Biosensor for Target DNA Detection.

Area of Science:

• Biomedical Engineering
• Molecular Diagnostics
• Biochemistry

Background:

• Accurate detection of disease-related DNA is crucial for early diagnosis and effective treatment.
• Existing methods for DNA detection can be complex and time-consuming.
• Development of sensitive and rapid biosensors is essential for disease management.

Purpose of the Study:

• To develop a sensitive and selective fluorescent biosensor for the detection of human immunodeficiency virus (HIV) DNA.
• To utilize thioflavin T (ThT) and G-quadruplex formation for enhanced fluorescence signaling.
• To evaluate the biosensor's performance in detecting target DNA in complex biological samples like human serum.

Main Methods:

• Construction of a fluorescent biosensor using thioflavin T (ThT) and G-rich DNA sequences.
• Design of hairpin DNA probes that release G-rich sequences upon target DNA binding.
• Induction of G-quadruplex formation by ThT, leading to enhanced fluorescence.
• Detection of target HIV DNA through the interaction with the G-rich sequence and ThT.

Main Results:

• The biosensor demonstrated sensitive detection of target DNA with a limit of detection as low as 2.4 nM.
• The developed biosensor exhibited satisfactory selectivity for the target DNA.
• The biosensor performed well in human serum, indicating its potential for real-world applications.
• A simple and rapid detection mechanism was achieved, relying on fluorescence enhancement.

Conclusions:

• A novel thioflavin T-induced G-quadruplex fluorescent biosensor was successfully developed for sensitive HIV DNA detection.
• The biosensor offers a simple, rapid, and selective method for DNA detection.
• The promising performance in human serum suggests the potential clinical applicability of this optical biosensor for target DNA detection.