Endocannabinoid analysis in GlucoEXACT plasma: Method validation and sample handling recommendations

Area of Science:

• Biochemistry
• Clinical Chemistry
• Analytical Chemistry

Background:

• Endocannabinoids (ECs) are implicated in numerous diseases, including inflammatory, cardiovascular, metabolic, and mental health conditions.
• Accurate quantification of ECs and related substances in biological fluids is crucial for clinical research and diagnostics.
• Pre-analytical variables, such as blood collection tube type and centrifugation time, significantly impact EC measurement reliability.

Purpose of the Study:

• To compare the performance of GlucoEXACT blood collection tubes against K3EDTA tubes for the quantification of ECs and EC-like substances.
• To validate a UHPLC-MS/MS method for EC analysis in human plasma.
• To assess the impact of pre-analytical conditions on analyte stability and optimize sample processing for reliable EC profiling.

Main Methods:

• Comparison of EC and EC-like substance concentrations using GlucoEXACT and K3EDTA tubes.
• Validation of a UHPLC-MS/MS assay for human plasma according to EMA and FDA guidelines.
• Systematic modification of pre-analytical conditions to evaluate analyte stability and optimize procedures.

Main Results:

• GlucoEXACT tubes yielded significantly lower EC and EC-like substance concentrations compared to K3EDTA tubes.
• GlucoEXACT tubes demonstrated an extended time window for stable EC concentrations.
• High agreement in EC profiles and disease-dependent patterns was observed between both tube types, despite differences in absolute values, except for 1/2-AG.

Conclusions:

• GlucoEXACT blood collection tubes offer enhanced stability and reliability for EC and EC-like substance analysis compared to K3EDTA tubes.
• Optimized pre-analytical procedures, including appropriate blood collection and sample processing, are essential for obtaining reliable peripheral EC insights.
• Despite analytical challenges, standardized methods enable valuable insights into EC profiles in disease states, such as inflammatory skin conditions.