Fragmentation of molecular ions in differential mobility spectrometry as a method for identification of chemical warfare agents

Maziejuk, Mirosław; Puton, Jarosław; Szyposzyńska, Monika; Witkiewicz, Zygfryd

doi:10.1016/j.talanta.2015.07.039

Cited by 20 publications

(10 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The intensity of the singly charged quinidine is increased fivefold, which suggests that charge striping occurs in the region between the ESI plume and the front end of the DMS before the SV affects the spatial separation of the two charges. The second factor is analyte fragmentation in the DMS cell upon ion heating due to the high effective temperature T eff . − The third factor is ion competition for proton between the analyte and modifier in the electrospray plume, which increases or decreases analyte signal depending on ESI solvent composition. Since roughly one-half of the DMS modifier defuses into the ESI source, the source’s atmosphere is changed and affects the ion transmission into the DMS cell.…”

Section: Resultsmentioning

confidence: 99%

Clustering and Nonclustering Modifier Mixtures in Differential Mobility Spectrometry for Multidimensional Liquid Chromatography Ion Mobility–Mass Spectrometry Analysis

2021

View full text Add to dashboard Cite

Modifiers provide fast and reliable tuning of separation in differential mobility spectrometry (DMS). DMS selectivity for separating isomeric molecules depends on the clustering modifier concentration, which is typically 1.5–3 mol % ratio of isopropanol or ethanol in nitrogen. Low concentrations (0.1%) of isopropanol were found to improve resolution and sensitivity but at the cost of practicality and robustness. Replacing the single-channel DMS pump with a binary high-performance liquid chromatography (HPLC) pump enabled the generation of modifier mixtures at a constant flow rate using an isocratic or gradient mode, and the analytical benefits of the system were investigated considering cyclohexane, n-hexane, or n-octane as nonclustering modifiers and isopropanol or ethanol as clustering modifiers. It was found that clustering and nonclustering modifier mixtures enable optimization of selectivity, resolution, and sensitivity for different positional isomers and diastereoisomers. Data further suggested different ion separation mechanisms depending on the modifier ratios. For 85 analytes, the absolute difference in compensation voltages (CoVs) between pure nitrogen and cyclohexane at 1.5 mol % ratio was below 4 V, demonstrating its potential as a nonclustering modifier. Cyclohexane’s nonclustering behavior was further supported by molecular modeling using density functional theory (DFT) and calculated cluster binding energies, showing positive ΔG values. The ability to control analyte CoVs by adjusting modifier concentrations in isocratic and gradient modes is beneficial for optimizing multidimensional LCxDMS–MS. It is fast and effective for manipulating the DMS scanning window size to realize shorter mass spectrometry (MS) acquisition cycle times while maintaining a sufficient number of CoV steps and without compromising DMS separation performance.

show abstract

Section: Resultsmentioning

confidence: 99%

Clustering and Nonclustering Modifier Mixtures in Differential Mobility Spectrometry for Multidimensional Liquid Chromatography Ion Mobility–Mass Spectrometry Analysis

2021

View full text Add to dashboard Cite

show abstract

“…However, with the increasing electric field energy, an increase in the number of inelastic collisions is observed. Introducing effect of the inelastic collisions requires the addition of a dimensionless coefficient ζ ( T ) to Formula (4) [ 41 ], which must be found experimentally. In the analysis presented here, this coefficient was skipped.…”

Section: Ion Fragmentation: Effective Ion Temperaturementioning

confidence: 99%

Detection and Identification of VOCs Using Differential Ion Mobility Spectrometry (DMS)

et al. 2021

View full text Add to dashboard Cite

The article presents a technique of differential ion mobility spectrometry (DMS) applicable to the detection and identification of volatile organic compounds (VOCs) from such categories as n-alkanes, alcohols, acetate esters, ketones, botulinum toxin, BTX, and fluoro- and chloro-organic compounds. A possibility of mixture identification using only the DMS spectrometer is analyzed, and several examples are published for the first time. An analysis of different compounds and their mechanisms of fragmentation, influence on effective ion temperature, and high electric field intensity is discussed.

show abstract

“…Nonetheless, using AC fields is possible, as the same voltage is effectively used several times while the ions pass the fragmenter. Hence, fragmentation in AC fields is a wellknown phenomenon in FAIMS 16 and has been used in a FAIMS-DMS setup, 17 as well as in a DT-IMS-fragmenter-DT-IMS setup. 18 These setups typically use sinusoidal or bisinusoidal waveforms for fragmentation to minimize the complexity of the required electronics components.…”

Section: T H Imentioning

confidence: 99%

Ion Fragmentation and Filtering by Alpha Function in Ion Mobility Spectrometry for Improved Compound Differentiation

et al. 2019

View full text Add to dashboard Cite

Collision induced dissociation (CID) is a widely used technique in mass spectrometry to better understand the structural composition of ions and to improve the identification of compounds beyond the analysis of m/z. By increasing the kinetic energy of ions in an electric field, the collisions with neutral molecules may result in bond breakage, dissociation, or fragmentation of the molecular ion into smaller fragments if the necessary onset energy is exceeded. In this work and for the first time, we demonstrate CID in a field asymmetric time of flight ion mobility spectrometer (FAT-IMS). In contrast to the commonly used devices in mass spectrometry, the FAT-IMS operates at ambient pressure and temperature. Furthermore, the FAT-IMS allows separation of ions prior to dissociation, employing the shift occurring in the FAT region and, thus, an improved assignment of fragment ions to selected precursor ions. In this work, the effect of the operation parameters on the fragmentation efficiency of the FAT separator is analyzed. As proof of concept, eight saturated alcohols were investigated. The results show the expected substance-specific fragmentation behavior, which can be used to generate additional orthogonal information about certain analytes via their fragmentation pattern. Furthermore, a method for prefiltering analytes in FAT-IMS by the alpha function is introduced to remove spectral interferences.

show abstract

Fragmentation of molecular ions in differential mobility spectrometry as a method for identification of chemical warfare agents

Cited by 20 publications

References 18 publications

Clustering and Nonclustering Modifier Mixtures in Differential Mobility Spectrometry for Multidimensional Liquid Chromatography Ion Mobility–Mass Spectrometry Analysis

Clustering and Nonclustering Modifier Mixtures in Differential Mobility Spectrometry for Multidimensional Liquid Chromatography Ion Mobility–Mass Spectrometry Analysis

Detection and Identification of VOCs Using Differential Ion Mobility Spectrometry (DMS)

Ion Fragmentation and Filtering by Alpha Function in Ion Mobility Spectrometry for Improved Compound Differentiation

Contact Info

Product

Resources

About