Solarix 15t ft icr ms

All of the offline top-down and bottom-up LC-MS/MS data were collected using Orbitrap platforms (Thermo Scientific, San Jose, CA, USA) and were completed using standard approaches as described in supplemental information. For the online LC-MS experiments, proteins were eluted using an analytical column which was packed with 20 cm of C4 reverse phase material (Halo Protein C4, 3.4 μm, 400Å) with a laser-pulled emitter tip. Proteins were loaded on the capillary reverse phase analytical column (360 μm O.D. × 150 μm I.D.) using a Waters nanoACQUITY UPLC (Waters Corporations, Milford, MA, USA) where mobile phase A consisted of 0.1% formic acid, 99.99% water, and mobile phase B consisted of 0.1% formic acid, 99.99% acetonitrile, eluting at 0.600 μL/min. Ions were generated using a Bruker Captive Spray nanoelectrospray source (Bruker Daltonics, Billerica, MA, USA) and directed into a Bruker SolariX 15T FTICR MS (Bruker Daltonics, Billerica, MA, USA). The mass spectrometer was set to scan from m/z 230-2,000, with a file size of 1M yielding a resolving power of 150,000 at m/z 400 (FID length: 0.5243 s). Ion optics were tuned as follows: accumulation hexapole (2 MHz, 1200 Vpp), time-of-flight delay (0.8 ms), funnel RF amplitude (280 Vpp), transfer optics (4 MHz, 290 Vpp), and ICR cell (sweep excitation power: 18%).