HPLC grade water and LC-MS grade methanal were purchased from Acros Organics (New Jersey). Lysophosphatidylcholine 17:1 (LPC 17:1) was purchased from Avanti Polar Lipids (Alabaster, AL). The extraction solvent used in this study was composed of 1 μM LPC 17:1 in 9 : 1 MeOH : H2O (v/v). Fused silica capillaries (50 μm ID, 150 μm OD) were purchased from Polymicro Technologies (Phoenix, AZ). The MinuteWeld epoxy glue was purchased from J-B Weld company (Sulphur Springs, TX). A 2000 grit silicon carbide sandpaper (STARCKE, Germany) was used to polish the SLE-MFP sampling port.
4′′ fused-silica substrates with a thickness of 1 mm were obtained from Siegert Wafer GmbH (Aachen, Germany). Potassium hydroxide solution (45%, extra pure) and MeOH (HPLC grade) were purchased from Carl Roth GmbH & Co. KG (Karlsruhe, Germany). Dioctyl sulfosuccinate sodium salt (≥99%) was purchased from Sigma-Aldrich GmbH (Taufkirchen, Germany).
4′′ fused-silica substrates with a thickness of 1 mm were obtained from Siegert Wafer GmbH (Aachen, Germany). Potassium hydroxide solution (45%, extra pure) and MeOH (HPLC grade) were purchased from Carl Roth GmbH & Co. KG (Karlsruhe, Germany). Dioctyl sulfosuccinate sodium salt (≥99%) was purchased from Sigma-Aldrich GmbH (Taufkirchen, Germany).