Advancing diagnostics with BODIPY-bismuthene DNA biosensors.

Area of Science:

• Nanomaterials Science
• Biosensor Technology
• Infectious Disease Diagnostics

Background:

• Early and accurate diagnosis of viral infections is crucial for effective treatment and public health.
• Existing diagnostic methods often require amplification steps, increasing time and complexity.
• Development of sensitive, rapid, and point-of-care diagnostic tools is highly desirable.

Purpose of the Study:

• To develop an electrochemical biosensor for early infection diagnosis.
• To detect specific virus sequences directly from nasopharyngeal swab samples.
• To utilize few-layer bismuthene hexagons (FLBHs) and a BODIPY (BDP) derivative (BDP-NaSO3) for enhanced detection.

Main Methods:

• Fabrication of an electrochemical biosensor platform using FLBHs.
• Immobilization of thiolated DNA capture probes on the FLBH platform.
• Utilizing BDP-NaSO3 as an electrochemical indicator for target sequence hybridization.
• Testing the biosensor's performance using SARS-CoV-2 specific sequences (RdRp gene).
• Validation of the biosensor with direct detection in nasopharyngeal swab samples.

Main Results:

• The FLBHs provided an improved platform for DNA probe immobilization, enhancing sensitivity.
• BDP-NaSO3 acted as an effective electrochemical indicator for hybridization events.
• The biosensor achieved a low detection limit of 4.97 fM for SARS-CoV-2 RdRp sequence.
• Selective and rapid detection was demonstrated, with a linear range from 16.6 fM to 100 fM.
• Successful detection of SARS-CoV-2 in nasopharyngeal swab samples at 19 Cts without amplification.

Conclusions:

• The developed electrochemical biosensor offers a sensitive, specific, and rapid method for early viral infection diagnosis.
• The combination of FLBHs and BDP-NaSO3 provides a powerful platform for direct nucleic acid detection.
• The biosensor's stability, low sample volume requirement, and point-of-care potential make it suitable for clinical settings.