[Determination of glyphosate and glufosinate in plasma samples by solid-phase extraction coupled with liquid...

Objective: To establish a rapid method for the determination of glyphosate and glufosinate residues in plasma samples by solid-phase extraction-liquid chromatography-tandem mass spectrometry (SPE-LC-MS/MS) . Methods: In March 2024, plasma samples were extracted and protein precipitated with methanol and purified using a weak cation exchange (WCX) SPE cartridge. Then the samples were separated on a Dikma Polyamino HILIC column (150 mm×2.0 mm, 5 μm) with a gradient elution of 1.0 mmol/L ammonium fluoride aqueous solution (pH=11) and acetonitrile as mobile phases. Analysis was performed using an electrospray ionization source (ESI) in multiple reaction monitoring (MRM) mode with internal standard quantification. The method's linearity, detection limits, spiked recovery and precision were then evaluated. Results: Glyphosate and glufosinate exhibited good linearity in the concentration range of 1.0-200.0 μg/L, with correlation coefficients of 0.9986-0.9992. The limits of detection (LODs) of glyphosate and glufosinate were 0.5 and 1.0 μg/L, respectively. At low, medium and high spiked concentrations, the spiked recovery rates and precision for glyphosate and glufosinate in plasma ranged from 92.5% to 113.2% and 3.01% to 11.23%, respectively. Conclusion: The SPE-LC-MS/MS method is simple, rapid, sensitive and accurate, and is suitable for the qualitative and quantitative analysis of glyphosate and glufosinate in plasma from poisoned patients.