Detection of a specific biomarker for Epstein-Barr virus using a polymer-based genosensor

Area of Science:

• Electrochemistry
• Biosensor Technology
• Molecular Diagnostics

Background:

• Epstein-Barr virus (EBV) poses significant health challenges, necessitating sensitive detection methods.
• Oligonucleotide-based genosensors offer a promising approach for specific nucleic acid detection.
• Electrochemical techniques provide a sensitive and cost-effective platform for biosensing.

Purpose of the Study:

• To develop and validate an electrochemical genosensor for the direct and indirect detection of Epstein-Barr virus (EBV).
• To assess the genosensor's sensitivity, specificity, and stability for EBV oligonucleotide targets.
• To demonstrate the genosensor's capability in discriminating between complementary, non-complementary, and single-base mismatch sequences.

Main Methods:

• Grafting of an EBV-specific oligonucleotide probe (EBV1) onto a poly(4-aminothiophenol)-modified electrode.
• Hybridization with a complementary target sequence (EBV2) in the presence of ethidium bromide as a DNA intercalator.
• Electrochemical detection of oxidation peak currents of ethidium bromide to quantify target DNA concentration.

Main Results:

• A linear relationship was observed between oxidation peak currents and complementary sequence concentrations (3.78–756 µmol·L⁻¹).
• The genosensor detected oligonucleotide targets down to 17.32 nmol·L⁻¹ with high specificity, distinguishing single-base mismatches.
• The biosensor demonstrated excellent specificity against common interfering substances and maintained stability for 120 days.

Conclusions:

• The developed electrochemical genosensor is highly effective for specific and sensitive detection of EBV oligonucleotides.
• This technology holds potential for diagnosing genetic diseases caused by point mutations and identifying EBV infections.
• The genosensor's stability and specificity make it a viable tool for molecular diagnostics.