Monocrotophos detection with a bienzyme biosensor based on ionic-liquid-modified carbon nanotubes.

Area of Science:

• Electrochemistry
• Biosensor Technology
• Materials Science

Background:

• Acetylcholinesterase (AChE) biosensors are crucial for detecting organophosphate pesticides.
• Existing AChE electrodes suffer from low stability and high overpotential.
• Organophosphates inhibit AChE activity, forming the basis for pesticide detection.

Purpose of the Study:

• To develop a novel, stable, and sensitive bienzyme electrode for organophosphate detection.
• To overcome the limitations of traditional AChE biosensors.
• To enhance sensitivity and stability using multiwalled carbon nanotubes and ionic liquids.

Main Methods:

• Constructed a bienzyme electrode: Cl/iron porphyrin (FePP)-modified MWCNTs/AChE/glassy carbon electrode.
• Utilized ionic liquids for covalent binding of FePP to the AChE carrier.
• Optimized conditions for monocrotophos detection.

Main Results:

• Achieved a low detection limit of 3.2 × 10^-11 mol/L for monocrotophos.
• Demonstrated good recovery rates (89-104%) for monocrotophos detection.
• Exhibited high stability, retaining 97.8% of original oxidation current after 5 weeks at 4 °C.

Conclusions:

• The novel FePP-MWCNTs/AChE biosensor offers enhanced stability and sensitivity for organophosphate detection.
• This biosensor is a promising tool for effective food safety monitoring.
• The developed electrode design addresses key limitations of previous AChE biosensor technologies.