Large-scale lipid analysis with C=C location and sn-position isomer resolving power

Abstract

Lipids play a pivotal role in biological processes and lipid analysis by mass spectrometry (MS) has significantly advanced lipidomic studies. While the structure specificity of lipid analysis proves to be critical for studying the biological functions of lipids, current mainstream methods for large-scale lipid analysis can only identify the lipid classes and fatty acyl chains, leaving the C=C location and sn-position unidentified. In this study, combining photochemistry and tandem MS we develop a simple but effective workflow to enable large-scale and near-complete lipid structure characterization with a powerful capability of identifying C=C location(s) and sn-position(s) simultaneously. Quantitation of lipid structure isomers at multiple levels of specificity is achieved and different subtypes of human breast cancer cells are successfully discriminated. Remarkably, human lung cancer tissues can only be distinguished from adjacent normal tissues using quantitative results of both lipid C=C location and sn-position isomers.

Trans‐omic profiling between clinical phenoms and lipidomes among patients with different subtypes of lung cancer

“…25 The specificity of human breast cancer cell subtypes was also noticed by measuring the quantitation of lipid C = C location and sn-position structure isomers. 26 The monounsaturated/saturated PC ratios were proposed to distinguish ADC histologic subtype-dependent variations among lepidic, acinar, papillary, micropapillary, solid, and mucinous phenomes. 27 The heterogeneity of lipidomic profiles and lipid metabolism could impact the specificity for lung cancer subtype, severity, stage, and drug efficacy, although characteristics of lipidomic profiles of lung cancer subtypes varied among studies because of different subjects, designs, methods, and analyses.…”

“…Choline-containing phospholipids of serum lipidomic profiles were considered as the potential TA B L E 7 Metastasis-associated lipid elements significantly elevated or declined alone in lung cancer patients with metastasis (more than twofold), as compared with healthy control (P-values) biomarkers to differentiate between stage I NSCLC and noncancer subjects, especially lysoPC (C26:0 and C26:1) and PC (C42:4 and C34:4). 26 The panel of lysoPC (18:0, 18:1, and 18:2) was suggested to detect early lung cancer patients from population screen, asymptomatic imaging detection, or stage IA-IIB. 16 We also selected several target panels with specificity on the basis of the fact that some lipids only altered in certain population of patients, for example, lysoPS (14 Those panels need to be furthermore validated and defined in larger studies with more patients, clinical phenomes and lipidomic profiles, and well-designed comparisons of related factors.…”

Analysis of food samples made easy by microextraction technologies directly coupled to mass spectrometry

“…For instance, recent advances in ion mobility could have a huge impact on rapid identification and quantitation of isobars potentially coextracted by the SPME devices 41–43 . Likewise, on‐line derivatization workflows (e.g., on‐coating derivatization 44 ) and tandem MS, as well as any combinations thereof, can be a potential solution when quantifying/identifying structural isomers present in a food sample 45 . Furthermore, high‐resolution MS and, particularly, tandem‐high resolution MS, have shown to be particularly useful when screening/multiple compounds with identical nominal masses and similar fragmentation features 12,28,46,47 .…”

Evaluation of LC-MS and LC×LC-MS in analysis of zebrafish embryo samples for comprehensive lipid profiling

“…The structure specificity of individual lipids, especially the C=C location and sn-position, could be qualitatively and Electronic supplementary material The online version of this article (https://doi.org/10.1007/s00216-020-02661-1) contains supplementary material, which is available to authorized users. quantitatively identified by coupling photochemical (Paternò-Bǜchi, PB) reaction with tandem MS (MS/MS) [15,16]. The versatility of LC is extremely successful because of many different separation mechanism such as reverse-phase (RP), normal-phase (NP), and hydrophilic interaction (HILIC) LC.…”