Two‐dimensional Fourier transform ion cyclotron resonance mass spectrometry: reduction of scintillation noise using Cadzow data processing

Abstract

In two-dimensional Fourier transform ion cyclotron resonance mass spectrometry (2D FTICR-MS), scintillation noise, caused mostly by fluctuations in the number of ions in the ICR cell, is the leading cause for errors in spectrum interpretation. In this study, we adapted an algorithm based on singular value decomposition and first introduced by Cadzow et al. (IEE Proceedings Pt. F 1987, 134, 69) to 2D FTICR-MS and we measured its performance in terms of noise reduction without losing signal information in the 2D mass spectrum.

Differentiating Fragmentation Pathways of Cholesterol by Two-Dimensional Fourier Transform Ion Cyclotron Resonance Mass Spectrometry

“…1 [14]: In cases where a fragment ion is also present as an abundant precursor on the autocorrelation line (i.e., front-end fragment ion species, for example), scintillation noise can cause additional peaks in the neutral loss lines that can overlap with the fragment ion peak [15]. Checking whether a peak in the neutral loss scan represents a fragmentation or scintillation noise is important to avoid faulty interpretations.…”

“…In 2010, 2D FT-ICR MS using the original pulse sequence was implemented again using IRMPD [13] and electron capture dissociation (ECD) [14] for peptides from a nanoelectrospray ion source. Advances in data processing and denoising algorithms were made [15,16], and the pulse sequence was optimized in order to maximize signal-to-noise ratios [17].…”

Phase relationships in two-dimensional mass spectrometry

“…In 2010, 2D MS was revived and successfully applied to a commercial FT-ICR mass spectrometer with infrared multiphoton dissociation (IRMPD), electron capture dissociation (ECD), and infrared activated electron capture dissociation (IR-ECD) as fragmentation methods [12][13][14]. Denoising algorithms have been proposed in order to decrease the amount of scintillation noise in 2D mass spectra and the pulse sequence was optimized [15][16][17]. 2D MS has been applied to small molecules and bottom-up and top-down proteomics, as well as polymer analysis [18][19][20][21][22][23][24][25].…”

2D FT-ICR MS of Calmodulin: A Top-Down and Bottom-Up Approach

“…These artefacts can come from harmonics (in both dimensions) because of the 2D Fourier Transform [12] or from the fluctuation in the amplitude or frequency of a signal-scintillation noise, the equivalent of t 1 noise in NMR spectroscopy [19]. Different algorithms for the de-noising of 2D mass spectra have been developed [20,21] and are now applied to all contemporary 2D-FT-ICR MS spectra, and as a result scintillation noise no longer represents a significant problem to 2D-FT-ICR MS spectra. The potential of 2D FT-ICR MS as an analytical method for the structural analysis of small molecules has been recently demonstrated on cholesterol, showing the possibility for the technique to differentiate various fragmentation pathways and interrogate detected species [22].…”