Paper-based platform for detection by hybridization using intrinsically labeled fluorescent oligonucleotide probes on...

Area of Science:

• Biotechnology
• Nanotechnology
• Analytical Chemistry

Background:

• Oligonucleotide detection is crucial for diagnostics and research.
• Existing methods often require target labeling and can be time-consuming.
• Quantum dots (QDs) offer unique optical properties for biosensing applications.

Purpose of the Study:

• To develop a paper-based platform for sensitive and selective oligonucleotide detection.
• To utilize intrinsically fluorescent probes enhanced by quantum dots for signal amplification.
• To demonstrate a rapid, label-free detection method with improved performance over solution-phase assays.

Main Methods:

• Conjugation of thiazole orange dye-labeled oligonucleotide probes to quantum dots (QDs).
• Immobilization of QD-probe conjugates onto a paper matrix for solid-phase hybridization.
• Excitation of dye probes via Förster Resonance Energy Transfer (FRET) from QD donors.
• Detection of target oligonucleotides based on fluorescence enhancement upon hybridization.

Main Results:

• Achieved a 20-fold enhancement in fluorescence emission compared to solution-based assays.
• Demonstrated a limit of detection of 0.1 picomoles for oligonucleotide targets.
• Showcased reduced sample preparation and data acquisition time.
• Confirmed reliable performance in complex matrices like goat serum.

Conclusions:

• The paper-based QD-enhanced platform enables rapid, sensitive, and selective oligonucleotide detection.
• This method eliminates the need for target labeling, simplifying assay procedures.
• The platform shows potential for point-of-care diagnostics and complex biological sample analysis.