A New LC-MS/MS-Based Method for the Simultaneous Detection of α-Tocopherol and Its Long-Chain Metabolites in Plasma...

Area of Science:

• Analytical Chemistry
• Biochemistry
• Pharmacokinetics

Background:

• Quantification of alpha-tocopherol (α-TOH) and its phase II metabolites (α-13'-COOH, α-13'-OH) presents analytical challenges due to vast concentration differences.
• Existing methods require separate analyses for α-TOH and its metabolites, increasing workflow complexity.

Purpose of the Study:

• To develop and validate a novel, simultaneous LC-MS/MS method for quantifying α-TOH and its metabolites in human serum.
• To address the analytical challenges associated with disparate analyte concentration ranges.

Main Methods:

• Simultaneous quantification using LC-MS/MS with deuterium-labeled internal standards (d6-α-TOH, d6-α-13'-COOH, d6-α-13'-OH).
• Utilized a pentafluorophenyl core-shell chromatography column for baseline separation.
• Employed solid-phase extraction (SPE) with HybridSPE® material for streamlined sample preparation.

Main Results:

• Achieved precise and accurate measurements for both α-TOH and its metabolites, with LOD and LOQ comparable to previous studies.
• Demonstrated effective compensation for matrix effects and ion suppression using deuterium-labeled standards.
• Validated calibration, accuracy, and precision parameters consistent with existing literature.

Conclusions:

• The developed method enables efficient simultaneous analysis of α-TOH and its metabolites, spanning up to three orders of magnitude in concentration.
• Streamlined sample preparation and analysis significantly accelerate pre-analytical workflows compared to separate methods.
• The method is highly suitable for large-scale studies investigating vitamin E metabolism and pharmacokinetics.