Efficient Discrimination and Removal of Phospholipids During Electromembrane Extraction from Human Plasma Samples

Abstract

Ultra-HPLC-MS/MS analysis of the donor solutions revealed that the phospholipids principally remained in the plasma samples. This proved that the phospholipids did not migrate in the electrical field and they were prevented from penetrating the supported liquid membrane.

Recurrent Topics in Mass Spectrometry-Based Metabolomics and Lipidomics—Standardization, Coverage, and Throughput

“…Mass transfer is driven by an electric field introduced between donor and acceptor phase via insertion of electrodes and application of direct current in the milliampere range, which speeds up the extraction process and enhances extraction yield compared to simple partitioningbased extraction. For optimized systems, selective analyte enrichment up to 100-fold and recoveries up to 100% 204 and excellent cleanup potential have been reported (salt-and protein-removal, 210 phospholipid-removal 211 ). The technique holds high potential for point of care analysis as enabled by parallelization and downscaling of analysis as well as implementation into microfluidic chips (e.g.…”

Sample preparation for polar metabolites in bioanalysis

“…Interferents such as proteins, salts or phospholipids do not cross the SLM and generally a low matrix effect such as ionization alteration is observed. 37,38 Because EME can extract either cations or anions, it can be an effective fractionation method according to the charge of the metabolite, in the case of very complex matrices. Nowadays, EME is largely used for the extraction of moderately lipophilic ionized compounds such as drugs and drug metabolites, 39,40 inorganic ions, 41,42 from a large variety of matrices such as plasma and waste water.…”

Improved Sensitivity in Hydrophilic Interaction Liquid Chromatography-Electrospray-Mass Spectrometry after Removal of Sodium and Potassium Ions from Biological Samples

“…Whiley et al [14] used both a cation exchange resin and an anion exchange resin to desalt large samples of pooled urine for preparative LC and downstream identification of urinary metabolites, however, there was no systematic investigation of the analytical performance or if all analytes were eluted from the ion exchange resins. Electromembrane extraction (EME) has been used to separate analytes such as pharmaceuticals and amino acids from inorganic ions as well as phospholipids in biological matrices, but EME requires different system setups for cationic, anionic and neutral analytes and may be cumbersome when a wide range of analytes is of interest [15][16][17]. To the authors' knowledge, there are no methods that aim to selectively remove inorganic alkali ions prior to bioanalysis of a wide range of small polar analytes that are neutral, positively as well as negatively charged for e.g.…”