Polypyrrole-polyvinyl sulphonate film based disposable nucleic acid biosensor

Area of Science:

• Electrochemistry
• Biosensor Technology
• Environmental Monitoring

Background:

• Organophosphate pesticides pose significant risks to environmental and human health.
• Development of sensitive and selective detection methods for organophosphates is crucial.
• Biosensors offer a promising platform for rapid and on-site pesticide detection.

Purpose of the Study:

• To develop and characterize novel disposable biosensors for the detection of organophosphate pesticides.
• To investigate the performance of double-stranded calf thymus deoxyribonucleic acid-polypyrrole-polyvinyl sulphonate (dsCT-DNA-PPy-PVS) films on indium-tin-oxide (ITO) coated glass plates as a sensing platform.
• To evaluate the additive effects of chlorpyrifos and malathion on the biosensor response.

Main Methods:

• Fabrication of dsCT-DNA-PPy-PVS films onto ITO coated glass plates.
• Characterization using cyclic voltammetry, Fourier-transform-infra-red (FTIR) spectroscopy, and atomic force microscopy (AFM).
• Amperometric detection of chlorpyrifos and malathion using the fabricated bioelectrodes.

Main Results:

• The dsCT-DNA-PPy-PVS/ITO bioelectrodes exhibited a rapid response time of 30 seconds.
• The developed biosensors demonstrated stability for approximately 5 months under desiccated storage at 25°C.
• Effective amperometric detection ranges were established for chlorpyrifos (0.0016-0.025 ppm) and malathion (0.17-5.0 ppm).
• The additive effect of these pesticides on the biosensor's amperometric response was investigated.

Conclusions:

• Disposable dsCT-DNA-PPy-PVS/ITO bioelectrodes are effective for the sensitive detection of organophosphate pesticides.
• The developed biosensor offers a stable and rapid platform for environmental monitoring of chlorpyrifos and malathion.
• Further investigation into the additive effects could refine pesticide residue analysis.