Broadband ion mobility deconvolution for rapid analysis of complex mixtures

Abstract

High resolving power ion mobility (IM) allows for accurate characterization of complex mixtures in high-throughput IM mass spectrometry (IM-MS) experiments. We previously demonstrated that pure component IM-MS data can be extracted from IM unresolved post-IM/collision-induced dissociation (CID) MS data using automated ion mobility deconvolution (AIMD) software [Matthew Brantley, Behrooz Zekavat, Brett Harper, Rachel Mason, and Touradj Solouki, J. Am. Soc. Mass Spectrom., 2014, 25, 1810-1819]. In our previous reports, we utilized a quadrupole ion filter for m/z-isolation of IM unresolved monoisotopic species prior to post-IM/CID MS. Here, we utilize a broadband IM-MS deconvolution strategy to remove the m/z-isolation requirement for successful deconvolution of IM unresolved peaks. Broadband data collection has throughput and multiplexing advantages; hence, elimination of the ion isolation step reduces experimental run times and thus expands the applicability of AIMD to high-throughput bottom-up proteomics. We demonstrate broadband IM-MS deconvolution of two separate and unrelated pairs of IM unresolved isomers (viz., a pair of isomeric hexapeptides and a pair of isomeric trisaccharides) in a simulated complex mixture. Moreover, we show that broadband IM-MS deconvolution improves high-throughput bottom-up characterization of a proteolytic digest of rat brain tissue. To our knowledge, this manuscript is the first to report successful deconvolution of pure component IM and MS data from an IM-assisted data-independent analysis (DIA) or HDMSE dataset.

Internal Standard Quantification Using Tandem Mass Spectrometry of a Tryptic Peptide in the Presence of an Isobaric Interference

“…However, we believe it may also be applied to other classes of molecules as well as isomerisms according to previous reports. ,,, This may indeed be useful providing there is enough difference in the fragmentation energetics of the compound and the interference allowing for the complete fragmentation of the contaminant while there is still signal for the analyte and the structurally similar internal standard (e.g., isotope-labeled). This strategy might also be used as an orthogonal separation technique to chromatography, e.g., in the case of coelution contaminant ,− and/or ion mobility for compounds with similar arrival time/collision cross sections. , …”

“…This strategy might also be used as an orthogonal separation technique to chromatography, e.g., in the case of coelution contaminant 18,22−25 and/or ion mobility for compounds with similar arrival time/collision cross sections. 26,27 ■ ASSOCIATED CONTENT * S Supporting Information…”

Recent developments in data acquisition, treatment and analysis with ion mobility‐mass spectrometry for lipidomics

“…tA: Arrival Time. mobilities due to the induced energy applied during the fragmentation [44]. Even more, if coeluting isomers and isobaric forms have different mobility behavior, their product ions can be discriminated, like it was done by Hellhake et al [45] with two isomeric oxylipins in human plasma.…”

“…But, when IM separation happens before fragmentation, precursor and product ions can be aligned according to their mobility behavior, helping in the product‐precursor assignation (Figure 5). However, data might require IM time alignment since precursor and product might show different mobilities due to the induced energy applied during the fragmentation [44]. Even more, if coeluting isomers and isobaric forms have different mobility behavior, their product ions can be discriminated, like it was done by Hellhake et al.…”