The Thermo Scientific Faims (high-field asymmetric waveform ion mobility spectrometry) interface is now available for the company's family of ion trap mass spectrometers
Faims capability eliminates interferences and significantly increases the number of the total spectra that match sequences and eliminates the need for additional time-consuming separation steps.
Well-suited for proteomics applications, as much as 90% of the total Faims spectra have been shown to match peptide sequences.
The combination of Faims and ion trap mass spectrometers addresses the needs of scientists working in laboratories who require more definitive results and multiple modes of separation from interferences.
Thermo Scientific ion trap mass spectrometers, when coupled with the Faims interface, allow users to selectively isolate target compounds based on a number of physical properties, including charge state and molecular conformation.
This selection of ions occurs before the introduction of the sample into the mass spectrometer, reducing background noise, increasing selectivity and improving spectral quality.
According to Michael MacCoss, assistant professor in the department of genome sciences at the University of Washington, using Faims on the Thermo Scientific LTQ provides the dynamic range and peak capacity of multidimensional protein identification technology (MudPit) in a one dimensional liquid chromatographic separation.
He states: "The separation of coeluting, isobaric components minimizes the number of MS/MS spectra acquired using data-dependent acquisition that are composed of multiple molecular species.
"Faims on the LTQ has substantially changed the way we think about proteomics profiling experiments".
Traditionally, up to twelve 60-minute MudPit steps are taken in order to fully separate protein/peptide mixtures requiring a significant amount of acquisition and processing time.
The Faims capability eliminates the need for these steps by doing direct infusion and enables the scanning of the entire mobility range in one minute with no need to do any additional separation, thus saving valuable time.
Adding the multiple degrees of separation capability of Faims for protein and peptide analysis enhances both selectivity and sensitivity of low-abundant proteins for identification and offers important benefits for applications such as biomarker research, protein profiling and protein structure characterisation.
Separation with Faims prior to MS analysis reduces the number of ions introduced into the ion trap, eliminating solvent ions which complicate identification, and singly-charged ions which render little peptide information.
This also significantly improves dynamic range and, when coupled with the inherent speed of the LTQ XL, results in an analysis on a chromatographic timescale.
Additionally, Faims allows for the separation of isobaric metabolites for easy identification and confirmation of metabolites, as well as affording improved overall spectral quality by removing endogenous background ions from formulations and dosing excipients.
The Faims interface also works with the Thermo Scientific TSQ Quantum series triple quadrupole mass spectrometers to increase selectivity and robustness in challenging assays.
