Reversed-phase ultrahigh-performance liquid chromatography-mass spectrometry (RP-UHPLC/MS) method is optimized for the quantitation of a large number of lipid species in biological samples, primarily in human plasma and serum. The method uses a C18 bridged ethylene hybrid (BEH) column (150 × 2.1 mm; 1.7 μm) for the separation of lipids from 23 subclasses with a total run time of 25 min. Lipid species separation allows the resolution of isobaric and isomeric lipid forms. A triple quadrupole mass spectrometer is used for targeted lipidomic analysis using multiple reaction monitoring (MRM) in the positive ion mode. Data are evaluated by Skyline software, and the concentrations of analytes are determined using internal standards per each individual lipid class.

• Klíčová slova
• High-throughput lipidomics, Mass spectrometry, Plasma, Quantitation, Reversed-phase, Serum, Ultrahigh-performance liquid chromatography,
• MeSH
• chromatografie s reverzní fází * metody   MeSH
• hmotnostní spektrometrie metody   MeSH
• kapalinová chromatografie-hmotnostní spektrometrie MeSH
• lidé MeSH
• lipidomika * metody   MeSH
• lipidy * analýza   MeSH
• rychlé screeningové testy metody   MeSH
• software MeSH
• tandemová hmotnostní spektrometrie metody   MeSH
• vysokoúčinná kapalinová chromatografie metody   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• lipidy * MeSH

Aliphatic hydrocarbons (HCs) are usually analyzed by gas chromatography (GC) or matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. However, analyzing long-chain HCs by GC is difficult because of their low volatility and the risk of decomposition at high temperatures. MALDI cannot distinguish between isomeric HCs. An alternative approach based on silver ion high-performance liquid chromatography (Ag-HPLC) is shown here. The separation of HC standards and cuticular HCs was accomplished using two ChromSpher Lipids columns connected in series. A gradient elution of the analytes was optimized using mobile phases prepared from hexane (or isooctane) and acetonitrile, 2-propanol, or toluene. HCs were detected by atmospheric pressure chemical ionization mass spectrometry (APCI-MS). Good separation of the analytes according to the number of double bonds, cis/trans geometry, and position of double bonds was achieved. The retention times increased with the number of double bonds, and trans isomers eluted ahead of cis isomers. The mobile phase significantly affected the mass spectra of HCs. Depending on the mobile phase composition, deprotonated molecules, molecular ions, protonated molecules, and various solvent-related adducts of HCs were observed. The optimized Ag-HPLC/APCI-MS was applied for characterizing cuticular HCs from a flesh fly, Neobellieria bullata, and cockroach, Periplaneta americana. The method made it possible to detect a significantly higher number of HCs than previously reported for GC or MALDI-MS. Unsaturated HCs were frequently detected as isomers differing by double-bond position(s). Minor HCs with trans double bonds were found beside the prevailing cis isomers. Ag-HPLC/APCI-MS has great potential to become a new tool in chemical ecology for studying cuticular HCs.

• Klíčová slova
• Neobellieria bullata, Periplaneta americana, double bonds, hydrocarbons, mass spectrometry, semiochemicals,
• MeSH
• atmosférický tlak MeSH
• plynová chromatografie s hmotnostně spektrometrickou detekcí MeSH
• spektrometrie hmotnostní - ionizace laserem za účasti matrice MeSH
• stříbro * chemie   MeSH
• uhlovodíky * MeSH
• vysokoúčinná kapalinová chromatografie metody   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• stříbro * MeSH
• uhlovodíky * MeSH

Lipids form a significant part of animal organs and they are responsible for important biological functions, such as semi-permeability and fluidity of membranes, signaling activity, anti-inflammatory processes, etc. We have performed a comprehensive nontargeted lipidomic characterization of porcine brain, heart, kidney, liver, lung, spinal cord, spleen, and stomach using hydrophilic interaction liquid chromatography (HILIC) coupled to electrospray ionization mass spectrometry (ESI/MS) to describe the representation of individual lipid classes in these organs. Detailed information on identified lipid species inside classes are obtained based on relative abundances of deprotonated molecules [M-H](-) in the negative-ion ESI mass spectra, which provides important knowledge on phosphatidylethanolamines and their different forms of fatty acyl linkage (ethers and plasmalogens), phosphatidylinositols, and hexosylceramides containing nonhydroxy- and hydroxy-fatty acyls. The detailed analysis of identified lipid classes using reversed-phase liquid chromatography in the second dimension was performed for porcine brain to determine more than 160 individual lipid species containing attached fatty acyls of different acyl chain length, double-bond number, and positions on the glycerol skeleton. The fatty acid composition of porcine organs is determined by gas chromatography with flame ionization detection after the transesterification with sodium methoxide.

• MeSH
• chromatografie kapalinová metody   MeSH
• chromatografie plynová metody   MeSH
• fosfatidylethanolaminy analýza   MeSH
• fosfolipidy analýza   MeSH
• hmotnostní spektrometrie s elektrosprejovou ionizací metody   MeSH
• hydrofobní a hydrofilní interakce MeSH
• játra chemie   MeSH
• ledviny chemie   MeSH
• lipidy analýza   chemie   MeSH
• mastné kyseliny analýza   MeSH
• mícha chemie   MeSH
• mozek - chemie MeSH
• myokard chemie   MeSH
• plasmalogeny analýza   MeSH
• plíce chemie   MeSH
• prasata MeSH
• slezina chemie   MeSH
• žaludek chemie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• fosfatidylethanolaminy MeSH
• fosfolipidy MeSH
• lipidy MeSH
• mastné kyseliny MeSH
• plasmalogeny MeSH