Advanced analytical method of nereistoxin using mixed-mode cationic exchange solid-phase extraction and GC/MS

Area of Science:

• Forensic Toxicology
• Analytical Chemistry
• Environmental Science

Background:

• Nereistoxin (NTX) and its analogues are widely used pesticides with high insecticidal activity but significant neurotoxicity in humans.
• NTX toxicity stems from blocking nicotinic acetylcholine receptors, leading to neuromuscular dysfunction and potential respiratory failure.

Purpose of the Study:

• To develop and validate a sensitive method for determining NTX in biological samples.
• To apply the developed method to a real-world fatal intoxication case.

Main Methods:

• Mixed-mode cationic exchange solid-phase extraction (SPE) for sample cleanup.
• Gas chromatography/mass spectrometry (GC/MS) for identification and quantification.
• Method validation including limit of detection, recovery, and calibration.

Main Results:

• The developed SPE-GC/MS method demonstrated superior detection limits and recovery rates compared to existing techniques.
• Excellent recoveries (97±14%) in blood samples and high R2 values (>0.99) for calibration curves were achieved.
• The method successfully identified and quantified NTX in postmortem specimens from a fatal cartap intoxication case.

Conclusions:

• A robust and efficient method for NTX determination in biological fluids was established.
• The method's application confirmed NTX intoxication as the cause of death in a suicide case.
• Quantified NTX levels in blood and stomach contents provided critical forensic evidence.