Dual-mode optical biosensor based on multi-functional DNA structures for detecting bioactive small molecules

Area of Science:

• Biotechnology
• Nanotechnology
• Analytical Chemistry

Background:

• Peroxidase-like activity is crucial for biosensing applications.
• Developing sensitive and selective detection methods for biomarkers like dopamine and glutathione is essential.
• Nanomaterials offer unique properties for advanced biosensor development.

Purpose of the Study:

• To prepare semiconducting polymer dots and hemin-functionalized DNA nanoflowers.
• To develop a dual-mode (fluorescent/colorimetric) biosensor for dopamine and glutathione.
• To evaluate the biosensor's sensitivity, selectivity, and applicability in complex biological samples.

Main Methods:

• Synthesis of semiconducting polymer dots.
• Preparation of hemin-functionalized DNA nanoflowers.
• Fabrication of a dual-mode biosensing platform.
• Assay development for dopamine and glutathione detection.

Main Results:

• The synthesized nanomaterials exhibited excellent peroxidase-like activity and high fluorescent brightness.
• The dual-mode biosensor achieved sensitive detection of dopamine at nanomolar (nM) and glutathione at micromolar (μM) levels.
• The biosensor demonstrated high selectivity and accuracy in analyzing complex biological samples.

Conclusions:

• The developed biosensor provides a sensitive and reliable platform for detecting dopamine and glutathione.
• The combination of polymer dots and DNA nanoflowers enhances sensing performance.
• This technology holds significant potential for clinical diagnostics and biomedical research.