Analysis of serum phospholipid profiles by liquid chromatography–tandem mass spectrometry in high resolution mode for evaluation of atherosclerotic patients

The impact of phospholipids and phospholipid removal on bioanalytical method performance

“…Zirconium (Zr) and titanium (Ti) have both been shown useful in preferentially binding to PLs for removal from nonbiological matrices (Li et al, 2013;Lin et al, 2012) in addition to their use in biological matrix analysis. Many of the SPE columns available contain either Zr or Ti (most often bound to silica), which act as a Lewis acid causing the PL phosphate moiety, which acts as a Lewis base, to adsorb to the column (Calderon-Santiago et al, 2014;Ferreiro-Vera et al, 2012;Pucci et al, 2009). Utilization of nanoparticles for this application has potential to improve PL retention vs the ZrO 2 powderbased products currently on the market (Li et al, 2013;Lin et al, 2012) owing to the greater surface area on which the PLs may adsorb.…”

“…Many different solvents have been tested to determine the best choice for clearing PLs that have adhered to the column, including acetonitrile (ACN), methanol (MeOH), dichloromethane (DCM), isopropanol (IPA), chloroform, n-hexane, and various mixtures of these, some including water. One study claims that none of these work well (Ismaiel et al, 2007) while other studies have shown acceptable PL removal with MeOH-containing solutions (Calderon-Santiago et al, 2014;Ferreiro-Vera et al, 2012;Ismaiel et al, 2008) and some have shown success with ACN-containing solutions (Ekdahl et al, 2013). Ammonium formate and formic acid solutions (of varying strengths) are also used in many studies that include PL separation or analysis, but these have not been studied individually for PL removal effectiveness.…”

“…Analysis of biological samples for the purpose of determination of drugs, metabolites and other xenobiotics is often hindered by the presence of these phospholipids, especially when using HPLC coupled with mass spectrometry (MS) (Furey et al, 2013;Kushon and Pike, 2012;Rossmann et al, 2015). Plasma phospholipids are also becoming a field of inquiry in and of themselves, for their possible use as biomarkers for disease states, among other reasons (Azzouz et al, 2005;Calderon-Santiago et al, 2014;Ham et al, 2006;Petkovic et al, 2001;Postle et al, 2007) and therefore improvements in isolating, removing, quantifying and qualifying these molecules have become increasingly important.…”

Racing for the True Metabolomics Signature of Coronary Artery Disease

“…Previous research has identified several metabolites related to gut microbiome [5][6][7], fatty acid metabolism [8], inflammation [9], steroid metabolism [10], sphingolipids [11], and phospholipids as biomarkers of CAD [11]. Many of these biomarkers were either not validated or could not be replicated in other cohorts.…”

“…However, despite several reports showing metabolomics markers successfully identifying coronary artery disease (CAD) [3,4], there is still lack of consensus on the true metabolomics signature of CAD.Previous research has identified several metabolites related to gut microbiome [5][6][7], fatty acid metabolism [8], inflammation [9], steroid metabolism [10], sphingolipids [11], and phospholipids as biomarkers of CAD [11]. Many of these biomarkers were either not validated or could not be replicated in other cohorts.…”