Amperometric immunosensor for ricin by using on graphite and carbon nanotube paste electrodes

Area of Science:

• Electrochemistry
• Biosensors
• Immunosensors
• Chemical Warfare Agents

Background:

• Ricin is a highly toxic protein and a scheduled chemical and biological warfare agent.
• Sensitive and rapid detection methods are crucial for environmental and security monitoring.
• Amperometric immunosensors offer a promising approach for detecting biological toxins.

Purpose of the Study:

• To develop and compare amperometric immunosensors for ricin detection in water samples.
• To evaluate the performance of multiwalled carbon nanotubes paste electrodes (MWCNTPE) against graphite paste electrodes (CPE).

Main Methods:

• Fabrication of graphite paste electrodes (CPE) and multiwalled carbon nanotubes paste electrodes (MWCNTPE).
• Utilizing a sandwich enzyme-linked immunosorbent assay (ELISA) system for ricin detection.
• Electrochemical characterization and sensitivity analysis of both electrode types.

Main Results:

• Both MWCNTPE and CPE showed a linear response proportional to ricin concentration.
• MWCNTPE exhibited a lower detection limit (0.625-25 ng/ml) compared to CPE (2.5-25 ng/ml).
• Scanning Electron Microscopy (SEM) indicated better antibody trapping in MWCNTPE, though electrochemical properties were identified as the primary driver for higher sensitivity.

Conclusions:

• Amperometric immunosensors, particularly those utilizing MWCNTPE, are effective for sensitive ricin detection.
• The enhanced sensitivity of MWCNTPE is mainly attributed to its superior electrochemical properties.
• This technology holds potential for rapid and reliable monitoring of ricin in environmental samples.