Electrochemical DNA biosensor for potential carcinogen detection in food sample

Area of Science:

• Food Safety
• Analytical Chemistry
• Biosensor Technology

Background:

• Carcinogens in food pose significant health risks.
• Developing sensitive and reliable detection methods for food contaminants is crucial.
• Electrochemical biosensors offer a promising platform for rapid and accurate analysis.

Purpose of the Study:

• To develop and optimize a nanocomposite-based electrochemical DNA biosensor for detecting potential carcinogens in food.
• To evaluate the efficacy of different DNA sequences in carcinogen detection.
• To validate the biosensor's performance against established methods.

Main Methods:

• Fabrication of a screen-printed electrode modified with gold nanoparticles and silica nanospheres.
• Immobilization of amine-terminated single-stranded DNA onto the modified electrode.
• Utilizing competitive binding assays with Methylene Blue (MB) and differential pulse voltammetry for detection.
• Optimization of various parameters including DNA sequence, MB concentration, and buffer conditions.

Main Results:

• The 24-base guanine-rich DNA sequence provided the best performance.
• Achieved a low detection limit of 0.0001 ppm with a linear range from 0.0001 to 0.1 ppm.
• Demonstrated high reproducibility with relative standard deviation below 5%.

Conclusions:

• The developed electrochemical DNA biosensor is effective for detecting food carcinogens.
• The 24-base guanine-rich DNA sequence is optimal for this biosensing application.
• The biosensor shows potential for routine food safety monitoring and was validated by Ames test.