Ethane-bridged hybrid monoliths with well-defined mesoporosity and great stability for high-performance peptide separation

Abstract

A novel kind of hybrid monolith with well-defined mesopore structure was prepared based on sol-gel condensation of 1, 2-bis(trimethoxysilyl)ethane (BTME) and tetramethoxysilane. Compared with terminal organosiloxanes used for preparation of conventional hybrid monoliths, BTME, as an ethane-bridged alkoxysilane precursor, could not only maintain the uniformity of pore size distribution, but also improve the chemical stability of the monolith via Si-C bonds in the framework. Owing to the controllable mesoporous structure and good stability, the monolithic column was used for the separation of peptides with half peak width less than 6 s and the run-to-run and column-to-column relative standard deviations (RSD) for the retention time of five standard peptides less than 2.5%, showing narrow peak width and good reproducibility. Moreover, the separation performance could be well maintained even after washed by the mobile phase with pH 11.0 at 50 °C. Furthermore, 100 cm-length monolithic column was prepared and successfully used for nanoRPLC-ESI-MS/MS analysis of HeLa cell lysate digests, and 5670 proteins corresponding to 37574 peptides were identified from 750 ng of the sample, showing great promising of “single-shot” large-scale in-depth proteomic research.