A simple, portable, electrochemical biosensor to screen shellfish for Vibrio parahaemolyticus

Area of Science:

• Electrochemistry
• Biosensing
• Food Safety

Background:

• Vibrio parahaemolyticus is a major cause of seafood-borne gastroenteritis.
• Accurate and rapid detection methods are crucial for public health.
• Existing methods can be time-consuming or require specialized equipment.

Purpose of the Study:

• To adapt and specify an electrochemical DNA detection mechanism for Vibrio parahaemolyticus detection in real samples.
• To develop a portable and practical screening tool for this pathogen.

Main Methods:

• Fabrication of a screen-printed carbon electrode modified with polylactide-stabilized gold nanoparticles.
• Utilizing methylene blue as a redox indicator for electrochemical detection.
• Measuring current response under controlled potential using a microprocessor.
• Assessing sensor performance with complementary, non-complementary, and mismatched oligonucleotides.

Main Results:

• The sensor demonstrated specific discrimination between different DNA sequences.
• Achieved a detection limit of 2.16 pM for DNA.
• Showed high sensitivity and reliability with a low relative standard deviation (4.33%) for differential pulse voltammetry measurements.
• Exhibited no cross-reactivity with other food-borne pathogens.
• Successfully identified Vibrio parahaemolyticus in spiked and unspiked fresh cockle samples.

Conclusions:

• The developed electrochemical sensor provides a sensitive, specific, and reliable method for detecting Vibrio parahaemolyticus.
• The sensor's simplicity and portability make it a promising practical screening tool for food safety applications.