Evaluation of meter-long monolithic columns for selected reaction monitoring mass spectrometry.

Proteome is extremely complex as many proteins with a large dynamic range are involved. Nano-liquid chromatography/mass spectrometry-based proteomics has made it possible to separate and identify thousands of proteins in one shot. Although the number of identified proteins in proteomics has significantly improved, it is necessary to increase detection sensitivity to clearly identify low-abundant proteins. In this study, we developed meter-long monolithic columns with a small inner diameter and applied them to selected reaction monitoring-based proteomics for improving proteomic detection sensitivity. Bovine serum albumin tryptic digests were analyzed with optimized selected reaction monitoring methods, and separation efficiency and detection sensitivity in each monolithic column were evaluated. As a result, peak capacity increased by about 1.8-fold and peak area of peptide levels increased by about 2.3-fold. Although flow rate was reduced during analysis with columns of a smaller inner diameter, the peak area reproducibility was maintained. These data displayed the value of meter-long monolithic columns with small inner diameter for selected reaction monitoring-based proteomics.