Updated project metadata.
This study demonstrates how the latest UHPLC (ultra-high-performance liquid chromatography) technology can be combined with high-resolution accurate-mass (HRAM) mass spectrometry (MS) and long columns packed with fully porous particles to improve bottom-up proteomics analysis with nano-flow liquid chromatography mass-spectrometry (nanoLCMS) methods. The increased back pressures from the UHPLC system enabled the use of 75 µm I.D. x 75 cm columns packed with 2 µm particles at a typical 300 nL/min flow rate as well as elevated and reduced flow rates. The constant pressure pump operation at 1500 bar reduced sample loading and column washing/equilibration stages and overall overhead time that maximizes MS utilization time. The versatility of flow rate optimization to balance the sensitivity, throughput with sample loading amount, and capability of using longer gradients contribute to a greater number of peptide and protein identifications for single-shot bottom-up proteomics experiments. The routine proteome profiling and precise quantification of >7,000 proteins with single-shot nanoLC-MS analysis open possibilities for large-scale discovery studies with deep dive into the protein level alterations.