One-Step Labeling and Purification: Accelerating FAHFA Detection in Vegetable Oils via Chemoselective Probe-Assisted LC–MS

Fatty acid esters of hydroxy fatty acids (FAHFAs) are
emerging
bioactive lipids in edible oils, but their trace-level presence and
matrix complexity hinder accurate analysis. Here, we designed a novel
chemoselective probe piperazine-modified silica (SiO2-PP) that specifically captures
FAHFAs while removing almost totally triglycerides in a one-step labeling
reaction. The probe enabled single-batch sample pretreatment within
30 min, integrating capture, purification, and signal amplification.
Coupled with liquid chromatography–mass spectrometry, the method
achieved high sensitivity (LOD: 0.0039–0.033 ng/mL) and enabled
quantification of 47 FAHFA isomers in 47 vegetable oil samples, with
concentrations ranging from 0.56 to 1.76 × 104 ng/g.
Five dominant isomers (e.g., 10-OAHSA) were identified, with olive
and peanut oils exhibiting the highest FAHFA concentrations. This
approach provides a promising platform for high-throughput functional
lipid profiling, effectively overcoming the inefficiencies of traditional
methods while significantly enhancing the assessment of vegetable
oil quality.