Esi tuning mix part no g2432a

Lipid profiling was performed using a 9.4 T Apex-ultra^TM hybrid Qh-FTICR mass spectrometer (Bruker Daltonics, Billerica, MA, USA) equipped with a 200 Hz, 355 nm Nd:YAG laser. In positive ion mode, Instrument calibration was performed using a phospholipid mixture (PC 24:0 at m/z 622.44423, PC 32:0 at m/z 734.56943, PC 36:0 at m/z 790.63203, and PC 44:2 at m/z 898.72593 from Avanti Polar Lipids, Inc.), and mass spectra were obtained over the m/z range of 500 ~1000. Three commercially available standard FAs (C_16:0 at m/z 255.23296, C_18:0 at m/z 283.26425, and C_22:6 at m/z 327.23294 from Sigma-Aldrich) with the ESI Tuning Mix (Part No. G2432A, Agilent Technology, Inc.) were used for instrument calibration over the m/z range of 100~1000 in negative ion mode. For data acquisition, a mass spectrum was accumulated in broadband mode by three full scans once with 100 laser shots using 1Mb data points over the above-mentioned ranges in the positive and negative ion modes, respectively. Ten mass spectra were randomly collected over a whole slide. All spectra were acquired using ApexControl 3.0.0 (Bruker Daltonics).