Pyrrolizidine alkaloids quantified in soil and water using UPLC-MS/MS

Area of Science:

• Environmental Chemistry
• Analytical Chemistry
• Toxicology

Background:

• Pyrrolizidine alkaloids (PAs) are plant-derived defense compounds with significant toxicity to humans and livestock.
• Monitoring PAs in environmental matrices is crucial due to their health risks.
• Existing analytical methods may lack the sensitivity or scope for comprehensive environmental monitoring.

Purpose of the Study:

• To develop and validate a sensitive Ultra-Performance Liquid Chromatography-tandem Mass Spectrometry (UPLC-MS/MS) method.
• To quantify pyrrolizidine alkaloids (PAs) in environmental samples, specifically soil and water.
• To establish a reliable analytical tool for assessing environmental contamination by PAs.

Main Methods:

• Sample preparation involved clean-up and pre-concentration using optimized MCX solid-phase extraction cartridges.
• PAs were identified and quantified using UPLC coupled with a Triple Quadrupole Mass Spectrometer (TQ-MS).
• Extensive optimization of chromatographic and mass spectrometric parameters was performed, including mobile phase composition, flow rate, and MS settings.

Main Results:

• The UPLC-MS/MS method demonstrated high sensitivity with an instrument limit of detection (LOD) of 2-7 μg L⁻¹ and a limit of quantification (LOQ) of 5-9 μg L⁻¹.
• Method linearity was validated up to 1000 μg L⁻¹, indicating its suitability for a wide range of concentrations.
• The method was successfully applied to analyze environmental samples from Denmark, quantifying 15 PAs in soil (3-1349 μg kg⁻¹) and surface water (4-270 μg L⁻¹).

Conclusions:

• A robust, fast, and sensitive UPLC-MS/MS method for PA quantification in soil and water has been successfully developed and validated.
• This represents the first report of quantified PAs in environmental samples using this advanced analytical technique.
• The established method provides a critical tool for environmental risk assessment and monitoring of PA contamination.