A versatile graphene-based fluorescence "on/off" switch for multiplex detection of various targets

Area of Science:

• Biomolecular sensing
• Nanomaterials in diagnostics
• Analytical chemistry

Background:

• Traditional molecular beacons (MBs) face limitations in multiplexing and complexity.
• Developing universal platforms for diverse analyte detection remains a challenge.
• Graphene oxide (GO) offers unique properties for biosensing applications.

Purpose of the Study:

• To design and validate a versatile molecular beacon-like probe using a self-assembled ssDNA-graphene oxide (ssDNA-GO) architecture.
• To demonstrate the probe's capability for multiplex sensing of various targets in a homogeneous solution.
• To establish the ssDNA-GO architecture as a universal platform for sensing applications.

Main Methods:

• Fabrication of a self-assembled ssDNA-GO architecture.
• Utilizing a fluorescence "on/off" switching strategy for signal transduction.
• Testing the probe's performance in multiplex detection of DNA, protein, metal ions, and small molecules.

Main Results:

• The ssDNA-GO probe demonstrated a simple, single-step, homogeneous solution-based sensing strategy.
• Achieved superior sensitivity and rapid response with minimal background interference compared to traditional MBs.
• Successfully detected sequence-specific DNA, thrombin, Ag(+), Hg(2+), and cysteine with low limits of detection (nM range).

Conclusions:

• The ssDNA-GO architecture serves as an excellent and versatile universal platform for multiplex analyte sensing.
• This design offers a simplified and highly effective alternative to conventional molecular beacons.
• The platform's adaptability by changing ssDNA sequences allows for broad applicability in diagnostics and research.