Quantitative analysis of acyl-lysophosphatidic acid in plasma using negative ionization tandem mass spectrometry

Challenges in accurate quantitation of lysophosphatidic acids in human biofluids

“…Chemical conversion of lysophospholipid such as LPC to LPA can also occur in the presence of strong acid ( 26 ). The most commonly reported sample preparation method for LPA extraction from biological fl uids involves LLE with acidification ( 3,12,14,15,18,19,(27)(28)(29). Scherer et al showed that under strong acidic conditions, LPC degrades to LPA in the presence of plasma, and the total LPA concentration in human plasma was almost 10-fold higher in plasma extracted under acidic conditions versus plasma extracted polypropylene microcentrifuge tube) was spiked with 10 µl of internal standard (IS) (C17:0-LPA) working solution (in methanol) followed by 200 ul of extraction buffer (30 mM citrate/40 mM sodium phosphate in water) and 600 µl of butanol.…”

High-Throughput Analysis of Sphingosine 1-Phosphate, Sphinganine 1-Phosphate, and Lysophosphatidic Acid in Plasma Samples by Liquid Chromatography–Tandem Mass Spectrometry

“…These values are in good agreement with previously reported concentrations (7, 11, 12, 14 -16 ). In contrast, the concentrations of total LPA measured after highly acidic extraction were much higher (approximately 5 mol/L), most likely because of LPC degradation (8 ).…”

“…Several methods lack coelution of the internal standard and the analyte, which is necessary to help compensate for potential matrix effects or for varying ionization efficiency due to mobile-phase gradients (7,10,11,14 ). Laborious sample preparation (8,15 ), large sample volumes (8,(11)(12)(13), time-consuming derivatization procedures (15 ), and a lack of sufficient validation (8 -11 ) exclude these methods from routine analysis. Only one methodology exists for combined measurement of LPA and S1P (11 ).…”

“…Therefore, as a first step, we used a modified extraction procedure according to Bligh and Dyer with 6 mol/L HCl (8,12 ). Although both LPA and S1P were extracted with efficiencies of 85%-95%, this extraction method had poor reproducibility for plasma samples.…”

Serum Lysophosphatidic Acid Level in Chronic Myeloid Leukemia

“…peritoneum of patients with ovarian cancer (14) and protects ovarian cancer cells against chemical drugs that induce apoptosis (15). The LPA is a potential gene expression mediator, particularly in cancer cells.…”