Thermo Fisher Scientific DIA proteomics capability for Q Exactive mass spectrometer

Thermo Fisher Scientific has introduced a data-independent acquisition (DIA) proteomics capability for the Thermo Scientific Q Exactive high-performance quadrupole-Orbitrap LC-MS/MS. The feature allows the mass spectrometer to collect MS/MS spectra on virtually all ions in a sample by selecting broad m/z windows and fragmenting all precursors in that window. This allows the instrument to quantify nearly all detected peptides in the sample in a single run.

Unlike other DIA-capable mass spectrometry platforms, which require switching to a triple quadrupole instrument to perform targeted peptide quantitation, Q Exactive LC/MS lets users perform both DIA and targeted quantification experiments on the same instrument.

The DIA data collected on the instrument can be processed with Thermo Scientific Pinpoint software 1.3. The DIA acquisition strategy adds another multiplexing method to the mass spectrometer, which already allows users to multiplex up to 10 precursor ions for quantification in full MS and MS/MS mode.

The mass spectrometer offers ultrahigh resolution up to 140,000, delivering accurate quantitation by decreasing interference from targeted peptides. This makes the technique useful for quantifying proteins/peptides of interest from DIA experiments. The instrument provides SRM-equivalent quantitative performance. The instrument control software is available as a developer’s kit for Q Exactive LC/MS users who want to acquire DIA capability.

The instrument is claimed to be the first commercially available mass spectrometer to combine quadrupole precursor selection with HR/AM Orbitrap mass analysis to deliver high-confidence quantitative/qualitative workflows. It has the ability to perform compound identification, quantitation and confirmation in a single run.