N heptadecanoyl d erythro sphingosine cer

HPLC grade dichloromethane (CH₂Cl₂) and methanol (CH₃OH) were purchased from Fisher Scientific Ltd. (Loughborough, UK). All other reagents were purchased from major commercial sources. Milli-Q water was obtained from a water purification system (Synergy, Millipore Corporation, Billerica, MA, USA). Phospholipid internal standards 1,2-dimyristoyl-sn-glycero-3-phosphocholine (dMPC), 1,2-dimyristoyl-sn-glycero-3-phosphoethanolamine (dMPE), 1,2-dimyristoyl-sn-glycero-3-phospho-(10-rac-glycerol) (dMPG), 1,2-dimyristoyl-sn-glycero-3-phospho-L-serine (dMPS), 1,2-dipalmitoyl-sn-glycero-3-phosphatidylinositol (dPPI), N-palmitoyl-D-erythro-sphingosylphosphorylcholine (NPSM), 1-nonadecanoyl-2-hydroxy-sn-glycero-3-phosphocholine (LPC (19:0)), 1,2-dimyristoyl-sn-glycero-3-propionic acid (dMPA), 1′,3′-bis[1–dimyristoyl-sn-glycero-3-phospho]-glycerol (tMCL) and N-heptadecanoyl-D-erythro-sphingosine (Cer (d18:1/17:0)) were purchased from Avanti Polar Lipids, Inc. (Alabaster, AL, USA).

The HPLC-grade dichloromethane, methanol, and acetonitrile were purchased from Fisher Scientific Ltd. (Loughborough, UK). All other reagents were purchased from major commercial sources. Milli-Q water (Synergy, Millipore Corporation, Billerica, MA, USA) was also used in the present work.
Polar lipids internal standards dimyristoyl phosphatidylcholine (dMPC), dimyristoyl phosphatidylethanolamine (dMPE), lysophosphatidylcholine (19:0 LPC), dipalmitoyl phosphatidylinositol (dPPI), dimyristoyl phosphatidylglycerol (dMPG), dimyristoyl phosphatidylserine (dMPS), tetramyristoyl cardiolipin (tMCL), sphingomyelin (17:0 SM (d18:1/17:0)), dimyristoyl phosphatidic acid (dMPA), and N-heptadecanoyl-D-erythro-sphingosine (Cer (d18:1/17:0)) were purchased from Avanti Polar Lipids, Inc. (Alabaster, AL, USA).