DNA nanosensor based on biocompatible graphene quantum dots and carbon nanotubes

Area of Science:

• Nanotechnology
• Biochemistry
• Analytical Chemistry

Background:

• Development of ultrasensitive biosensors is crucial for early disease detection and genetic analysis.
• Graphene quantum dots (GQDs) offer excellent fluorescence properties and biocompatibility.
• Carbon nanotubes (CNTs) possess unique optical properties suitable for FRET-based sensing.

Purpose of the Study:

• To develop an ultrasensitive nanosensor for DNA detection using fluorescence resonance energy transfer (FRET).
• To leverage the properties of graphene quantum dots (GQDs) and carbon nanotubes (CNTs) for enhanced DNA sensing.
• To achieve highly sensitive and reproducible detection of low DNA concentrations.

Main Methods:

• Preparation of graphene quantum dots (GQDs) with high quantum yield as fluorophores.
• Labeling DNA probes with GQDs and utilizing oxidized carbon nanotubes (CNTs).
• Facilitating FRET between GQDs and CNTs through π-π interactions for self-assembly.
• Distinguishing complementary and mismatched DNA sequences based on FRET efficiency.

Main Results:

• The nanosensor demonstrated high sensitivity and reproducibility in distinguishing DNA sequences.
• An ultralow detection limit of 0.4 nM for DNA was achieved.
• A broad linear span of up to 133.0 nM was observed for the DNA detection method.

Conclusions:

• The developed FRET-based nanosensor offers a highly sensitive and reliable platform for DNA detection.
• The use of biocompatible GQDs and CNTs ensures the potential for in vivo applications.
• This approach provides a promising tool for analyzing low concentrations of nucleic acids.