Combined utilization of ion mobility and ultra‐high‐resolution mass spectrometry to identify multiply charged constituents in natural organic matter

Abstract

Natural organic matter as complex biogeochemical non-repetitive material was investigated with ion mobility mass spectrometry (IMS) and ultra-high-resolution Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) approaches in order to unravel the existence of multiply charged state constituents. Hereby we describe and assign the potential molecular formulae of these doubly charged species, derived from FTICR-MS, and the existence of these species was confirmed via IMS. The parallel application of these powerful techniques enabled the boundaries of the understanding of natural organic matter to be pushed further.

Impact of instrument and experiment parameters on reproducibility of ultrahigh resolution ESI FT-ICR mass spectra of natural organic matter

“…These additional peaks are not present in full scan mode under any conditions. We attribute these masses to multiply (negatively) charged SRFA compounds, consistent with previous observations (Brown and Rice, 2000;Gaspar et al, 2009). …”

“…Solution composition has been shown to alter the apparent molecular weight distribution of DOM mass spectra (Brown and Rice, 2000;Gaspar et al, 2009). Here, we examine the effects of solvent composition on spectral reproducibility in terms of the number of peaks and the percent of peaks shared between injection replicates of negative ion mode SRFA spectra.…”

“…To date, most ESI FT-ICR MS analyses of DOM have addressed analytical challenges associated either with sample preparation and ion production, or with data analysis and interpretation. Researchers have made important contributions in these areas by optimizing protocols for DOM extraction and concentration (Kim et al, 2003;Koprivnjak et al, 2006;Dittmar et al, 2008;Morales-Cid et al, 2009), chromatographic pre-separation (Fievre et al, 1997;Koch et al, 2008;Reemtsma et al, 2008;Stenson, 2008;Gaspar et al, 2009), and ESI direct infusion (Brown and Rice, 2000;Kujawinski et al, 2002;Stenson et al, 2003;. Major advances have also been made for elemental formula assignments (Koch et al, 2005;Kujawinski and Behn, 2006;Koch et al, 2007;Kunenkov et al, 2009), graphical andcompositional analysis (Kim et al, 2003;Stenson et al, 2003;Wu et al, 2004;Koch and Dittmar, 2006), and multivariate statistical analysis (Koch et al, 2005;Koch et al, 2008;Rossello-Mora et al, 2008;Gougeon et al, 2009;Kujawinski et al, 2009).…”

Physico-chemical characterization of SOA derived from catechol and guaiacol – a model substance for the aromatic fraction of atmospheric HULIS

“…Electrospray injection was followed in negative mode with an APOLLO II electrospray source in flow injection at 2 µl/min (Gaspar et al, 2009, andSchmitt-Kopplin et al, 2010). The molecular formulae were batch-calculated by a software tool, written in-house and achieving a maximum mass error of ≤0.2 ppm.…”

“…The molecular formulae were batch-calculated by a software tool, written in-house and achieving a maximum mass error of ≤0.2 ppm. The generated formulae were validated by setting sensible chemical constraints (N rule, O/C ratio≤1, H/C ratio≤2n + 2, element counts: C≤80, H unlimited, O≤60) in conjunction with an automated theoretical isotope pattern comparison (Gaspar et al, 2009). Even enabling up to 3 N and 3 S resulted in mainly CHO types of elementary formulae (only few formulae corresponding to impurities were found as CHNO, CHOS and CHNOS, which are caused from the quartz filters.…”