Electrophoresis-Correlative Data-Independent Acquisition (Eco-DIA) Improves the Sensitivity of Mass Spectrometry for Limited Proteome Amounts

In this project, we developed electrophoresis-correlative (Eco) data-independent acquisition (DIA) mass spectrometry (MS). We recognized a correlation between the measured mass-to-charge (m/z) and migration time (MT) for peptides during capillary electrophoresis (CE) electrospray ionization (ESI) MS. We leveraged this relationship to dynamically tailor the experimental settings of DIA on an orbitrap mass spectrometer. This approach substantially improved utilization of the limited duty cycle during tandem MS and detection sensitivity compared to the classical DIA. From 1 ng of the standard HeLa proteome digest, Eco-DIA identified ~38% more proteins than conventional DIA, without the assistance of a project-specific spectral library. Proteins that were quantified exclusively by Eco-DIA were in the lower abundance range. Eco-DIA improved the sensitivity of detection from limited amounts of proteomes using CE-ESI-MS.