Accela ltq orbitrap xl

Mass spectrometry (MS) was performed using a Thermo Fisher Accela LTQ Orbitrap XL hybrid mass spectrometer (Thermo Fisher Scientific, Bremen, Germany) equipped with an electrospray ionization (ESI) interface. The ESI source was set in positive ionization mode. Mass calibration was performed in accordance with the manufacturer's guidelines, using a standard solution mix of Ultramark, the tetrapeptide Met-Arg-Phe-Ala (MRFA) acetate salt, sodium taurocholate, and sodium dodecyl sulphate. The ionization and tube lens voltages were 4.2 kV and 86 V, respectively. Sheath and auxiliary gas (nitrogen) pressures were set at 20 and 5 units, respectively. Capillary temperature was set at 350°C. MS acquisition was set with a scan range of 150-1300 m/z and a resolving power of 30000 for full-scan.

The HPLC samples from all matrixes were injected into the LC-MS system (Accela-LTQ Orbitrap XL, Thermo Fisher Scientific K.K.) with electrospray ionization (ESI), in negative mode using the following settings: MS, Fourier transformation (FT, resolution: 30000); MS², higher energy collisional dissociation; sheath gas flow rate, 40 arb: aux gas flow rate, 5 arb: spray voltage, 5.00 kV; capillary voltage, −13.00 V; capillary temperature, 350 °C; collision energy, 130; and tube Iens, −163.12 V.
The M1 peak in the faeces samples from 48–96 h was fractionated by HPLC under alkaline conditions and reconstituted with methanol/water (7:3, v/v). The sample was applied to LC-MS under acidic conditions with ESI, in positive mode and the following settings; MS, Fourier transformation (FT, resolution: 30000); MS², higher energy collisional dissociation; sheath gas flow rate, 60 arb: aux gas flow rate, 20 arb: spray voltage, 5.00 kV: capillary temperature, 350 °C; collision energy, 45; and tube lens, 130.00 V.

Chromatographic analysis was performed using a Thermo Fisher Accela UPLC system (Thermo Fisher Scientific, San Jose, CA, United States) equipped with a quaternary pump solvent management system, an online degasser, a diode-array detector (DAD), a column compartment, and an auto-sampler using a Phenomenex UPLC Kinetex C18 column (2.1 × 100 mm, 1.7 μm). Chromatographic separation conditions were as follows: Flow rate: 0.2 ml/min; Injection volume: 3 μl; Column temperature: 25°C; Mobile phase A: an aqueous solution of 0.1% formic acid; Mobile phase B: acetonitrile; An elution gradient: 5%–25% B from 0–5 min, 25%–60% B from 5–28 min, 60%–90% B from 28–38 min and 90% B between 38–42 min; Detection wavelengths: 214, 254, and 280 nm. Mass spectrometry (MS) was performed using a Thermo Fisher Accela LTQ Orbitrap XL hybrid mass spectrometer (Thermo Fisher Scientific, Bremen, Germany) equipped with an electrospray ionization (ESI) interface. The ESI source was set in positive ionization mode. MS acquisition was set with a scan range of 150–1300 m/z and a resolving power of 30,000 for full-scan (Fan et al., 2018 (link)).