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The concurrent utilization of electric and magnetic fields in static mass analyzers proves highly effective in sparticle separation solely based on their masses, thereby ensuring remarkable analytical capabilities. Highresolution mass analyzers employ an achromatizing electrostatic system to precisely focus ion radiation by energy. Devices featuring zero energy dispersion are created through the collaborative action of electric achromatizing systems and the magnetic field within the analyzer, resulting in ion separation based solely on mass. Expanding the ion beam prior to its magnetic field exposure enhances the overall quality of static mass analyzers. This article delves into a static mass analyzer with dual ion beam focusing, elucidating the ion acceleration and deceleration processes at electrode boundaries, their focalization via a transaxial lens, and the impact of the electrostatic prism's refractive surface on the mass analyzer's "quality" parameter. Additionally, the transition from a sector homogeneous magnetic field to the fields generated by a two-dimensional magnetic prism and a three-electrode transaxial focusing lens is explored to augment the mass analyzer's linear dispersion. To refine ion beam focus pre-magnetic field entry, the proposed adoption of a two-dimensional electrostatic prism promises heightened linear dispersion in the mass analyzer while expanding the beam pre-magnetic field entry. This study also examines the impact of a two-dimensional electric prism on the charged particle beam, presenting an approximate expression for its angular energy dispersion. It is demonstrated that a prism-based mass analyzer integrating two-dimensional electric and magnetic prisms enables energy-focused operations alongside enhanced linear dispersion and reduced linear dimensions. [ABSTRACT FROM AUTHOR]

Mass spectrometers are essential instruments for in situ analysis of planetary materials. Ideally, a space flight mass spectrometer would have a mass range from ∼10 u to at least 500 u to enable analysis of organic molecules to aid in searching for the requirements for life; capability for high precision isotope ratios of carbon, nitrogen, oxygen, sulfur, and noble gases to understand solar system evolution and functioning; and ability to resolve isobaric interferences at low m/z such as CO and N 2 to study planetary atmospheres. Despite the considerable progress in flight mass spectrometry since the 1970s, no single flight mass spectrometer has all these ideal characteristics. In this paper, we present a proof-of-concept super-resolution coded aperture cycloidal miniature mass spectrometer (SR-CAMMS) for planetary science. Design considerations and preliminary results are presented including: a mass range of 10–260 u with resolution of 0.5 u or better; the ability to resolve the isobaric interference between CO and N 2 at m/z = 28 u using sampling-super resolution; and the ability to acquire isotope ratios with Poisson statistics limited precision. Thus, the instrument met all design considerations except mass range, which was expected to be 10–500 u; reasons for this discrepancy are discussed in the paper. [Display omitted] • Super-resolution coded aperture miniature mass spectrometer: (SR-CAMMS). • Combines cycloidal mass analyzers, coded apertures, super-resolution, array detectors. • SR-CAMMS demonstrates mass range of 10–270 with 0.5 u or better resolution. • SR-CAMMS demonstrates isobaric separation of N 2 and CO using super-resolution. • SR-CAMMS demonstrates Poisson statistics limited isotope ratio precision with N 2. [ABSTRACT FROM AUTHOR]

A double potential well flat ion trap was designed as an ion accumulating and focusing device for multi-reflection time-of-flight mass analyzer. Two potential wells of the trap were severally used for accumulation of injected ions, controlled cooling and ejection of trapped ions, which had features to accumulate ions continuously and cool ion for almost one period. While a flat ion trap with only one potential well is a traditional and excellent ion accumulating and focusing device, which has an intermittent ion accumulation and an ion cooling around half period. Compared with the single potential well flat ion trap, the double potential well flat ion trap had better performance on ion accumulation and focusing in principle. Four steps to run the trap were simulated and researched by an ion optics simulator of SIMION 8.1. The first step was ion accumulation, ions were successively injected into the trap, and then stored and accumulated in the first potential well. The second step was ion transfer, the trapped ions were transferred from the first potential well to the second potential well. The third step was ion cooling, the trapped ions were confined in the second potential well, and were simultaneously cooled by collisions with 0.5 Pa He. The fourth step was ion ejection, the trapped ions were ejected from the trap and focused into the next device. Ion optics simulations indicated that the trap had a period from 1 ms to above 10 ms, a total ion transmission efficiency of 83%, and an ion flux of at most 1.6×106 ions. In addition, ion packets ejected from the trap had thermalized with radial diameters of 1.0 and 1.0 mm, angular standard deviations of 24 mrad and 16 mrad, and an energy standard deviation of 15 eV. This trap can be coupled with and provide high-flux and full-focusing ion packets for multi-reflection time-of-flight mass analyzers, due to an excellent suitability between the operation of the analyzer and the period, the ion transmission efficiency, the ion flux, and ejected ion packets of the trap. [ABSTRACT FROM AUTHOR]

This review describes the importance of UHPLC-MS in different fields and highlights the advancement in this hyphenated technique. The hyphenation of UHPLC-MS provides a standard modernized platform for many applications in pharmaceutics, environmental analysis, food industry and forensic science. The features of UHPLC-MS are higher degree of automation, shorter analysis time, better reproducibility and higher sensitivity which make this technique superior to other hyphenated techniques. [ABSTRACT FROM AUTHOR]

We report the effect of N2 gas‐mixing in the xenon electron cyclotron resonance (ECR) plasma, and abundance‐dependent novel, exciting and unusual trends of the isotope anomaly. The xenon plasma was produced using a 10 GHz all‐permanent‐magnet NANOGAN ECR ion source, and the charge state distributions of naturally abundant six stable xenon isotopes with and without N2 gas‐mixing (at 25%, 50%, and 75%) were recorded. The intensity ratio of the heavier to lighter isotope, where the heavier isotope is less abundant, showed a clear signature of the isotope anomaly as explained by the linear Landau wave damping theory. Contrary to the theoretical prediction that the isotope anomaly should vanish with a relatively large fraction of the heavier isotope in mixed plasmas, the trends of intensity ratios observed in such cases are very unusual and have almost the mirror‐symmetrical shapes of those trends recorded with less abundant heavier isotope. Further, the effect of relative mass difference on the isotope anomaly was also evidenced. The N2 gas‐mixing of the xenon plasma at 25% and 50% shifted the entire charge state distribution toward the higher intensity side owing to the supply of additional electrons that caused high ionization efficiency. However, a prominent gas‐mixing effect was observed at 75% of N2 mixing in the xenon plasma beyond the +7 charge state. The abundance‐dependent unusual trends in isotope anomaly have been explained by considering different ionic temperatures, ion heating by the wave damping, and Coulomb scattering in the core of the plasma. [ABSTRACT FROM AUTHOR]

With the advent of technologies such as ion array detectors and high energy permanent magnet materials, there is renewed interest in the unique focusing properties of the cycloidal mass analyzer and its ability to enable small, high‐resolution, and high‐sensitivity instruments. However, most literature dealing with the design of cycloidal mass analyzers assumes a single channel detector because at the time of those publications, compatible multichannel detectors were not available. This manuscript introduces and discusses considerations and a procedure for designing cycloidal mass analyzers coupled with focal plane ion array detectors. To arrive at a set of relevant design considerations, we first review the unique focusing properties of the cycloidal mass analyzer and then present calculations detailing how the dimensions and position of the focal plane array detector relative to the ion source determine the possible mass ranges and resolutions of a cycloidal mass analyzer. We present derivations and calculations used to determine the volume of homogeneous electric and magnetic fields needed to contain the ion trajectories and explore the relationship between electric and magnetic field homogeneity on resolving power using finite element analysis (FEA) simulations. A set of equations relating the electric field homogeneity to the geometry of the electric sector electrodes was developed by fitting homogeneity values from 78 different FEA models. Finally, a sequence of steps is suggested for designing a cycloidal mass analyzer employing an array detector. [ABSTRACT FROM AUTHOR]

An ion optical design of a high resolution multi-turn time-of-flight mass analyzer (MT-TOF MA) is presented. The analyzer has rotationally symmetric main electrodes with additional mirror symmetry about a mid-plane orthogonal to the axis of symmetry. Rotational symmetry allows a higher density of turns in the azimuthal (drift) direction compared to MT-TOF MAs that are linearly extended in the drift direction. Mirror symmetry about a mid-plane helps to achieve a high spatial isochronicity of the ions' motion. The analyzer comprises a pair of polar-toroidal sectors S1 and S3, a pair of polar (trans-axial) lenses, and a pair of conical lenses for longitudinal and lateral focusing. A toroidal sector S2 located at the mid-plane of the analyzer has a set of embedded drift focusing segments providing focusing and spatial isochronicity in the drift direction. The ions' drift in the azimuthal direction can be reversed by using dedicated reversing deflectors. This gives the possibility of several operational modes with different numbers of turns and passes in the drift direction. According to numerical simulations, the mass resolving power of the analyzer ranges from ∼ 40 k (fwhm) at small (typically below ten) numbers of turns to ∼ 450 k (fwhm) at 96 turns. [ABSTRACT FROM AUTHOR]

An ion-optical design of a new sector field multi-turn time-of-flight analyzer is proposed. The analyzer forms oval-type spiral ion trajectories and possesses second order time-of-flight focusing with respect to both energy and spatial (coordinate and angular) spreads in ion packets. The analyzer is based on a combination of cylindrical electrostatic sectors and a periodic array of 2D lenses. The energy and spatial acceptances of the analyzer are compatible with the acceptances of existing multi-reflection analyzers based on planar ion mirrors, while, according to simulations, the space charge capacity of the sector field analyzer is essentially larger than of the mirror-type ones. Image 1 [ABSTRACT FROM AUTHOR]

Based on the analysis of the results of the study of various designs of multi-electrode harmonized Kingdon traps, we propose a new type of trap with two merged internal electrodes that has the ability to capture and accumulate ions formed inside. We also investigated the influence of inaccuracies in the manufacture of the electrodes on the field inside such trap. The four-electrode trap, which actually degenerates into a two-electrode device with traces of two other electrodes present at the ends of the internal electrodes (their splitting) has been found as the less sensitive to inaccuracies caused by manufacturing and cutting the ends of trap electrodes. We show that a mass spectrometer with a relatively high resolving power can be created on the basis of such a trap. The creation of the traps requires the manufacture of complex electrodes with demanded accuracy of their surfaces. This becomes possible with the advent of 3D printers.Multi electrode harmonize Kingdon trap with fused elctrode pares [ABSTRACT FROM AUTHOR]

The paper summarizes original developments of gridless ion mirrors for high-resolution multi-reflection time-of-flight mass spectrometers (MR TOF MS). Optimized mirror geometries and electrostatic field distributions reach up to the 5th order isochronicity with respect to the energy spread and up to the 3rd order full isochronicity per energy, spatial and angular spreads of ion packets. Using a retarding focusing field at the mirror entrance doubles the ion transport energy at limited highest voltages. In planar analyzers with a zig-zag ion path, quasi-planar mirrors eliminate the 2nd order dependence of the flight time on the ion packet width in the drift direction. Improved MR TOF analyzers of 1 m size provide well over one million aberration limit at realistic ion packets parameters past orthogonal accelerators. Because of high order isochronicity the aberration limit rapidly grows with the analyzer size or when using narrower ion packets. In experiments, improved analyzers with one meter size demonstrate up to 300 000 mass resolving power at the full mass range and 500 000 at the restricted mass range. Improved ion mirrors with two-dimensional electrostatic fields are applicable for TOF MS, electrostatic traps and open electrostatic traps in planar and hollow cylindrical geometries. [ABSTRACT FROM AUTHOR]

A novel three-dimensional square ion trap is reported as a mass analyzer or an ion transfer device. The square ion trap was constructed with six square planar electrodes while the electric field was optimized by changing their relative positions to arrange the strength of higher-order fields. Ion trajectory simulations demonstrate the square ion trap efficiently operates with radial and axial excitation. Additionally, ions ejected from the radial direction contained lower kinetic energies and their energy distribution were more centralized. These properties may improve the ion transfer efficiency. [ABSTRACT FROM PUBLISHER]

Ion capture from an external nano-electrospray ionization source in an electrostatic linear ion trap has been effected by in-trap potential lift so as to avoid a time-dependent frequency drift of trapped ions. This phenomenon was observed when using mirror switching for capturing ions and compromised the mass resolution when using Fourier transform techniques for mass determination. A dual image charge detection approach was also implemented to compensate for losses in mass resolution associated with increasing the length of the electrostatic trap to accommodate the lift region. The potential lift approach for ion capture led to no detectable frequency shifts, thereby enabling the achievement of pressure-limited theoretical resolutions. For example, a resolution of roughly 11,000 M/ΔM FWHM was observed for a carborane anion population of average m / z = 520 at a transient length of 125 ms. The use of the dual detector approach led to an increase (∼12%) in the ion frequencies used for mass analysis, which more than compensated for the effect of increasing the length of the electrostatic trap. Although the implementation of the potential lift approach and dual detectors were successful in their objectives, these changes resulted in a narrower m / z range for a single ion injection event relative to mirror switching. Furthermore, the dual detector approach resulted in a higher noise floor and a more complicated frequency spectrum due to asymmetries in the electric fields of the ion trap. [ABSTRACT FROM AUTHOR]

A novel linear ion trap mass analyzer featuring half round rod electrodes (HreLIT) has been built. It is mainly composed of two pairs of stainless steel electrodes which have a cross-section of half round rod and a pair of end electrodes. The HreLIT has a simple structure and so it could be assembled by hand with relatively high mechanical accuracy. The external dimension of HreLIT is 50 mm × 29.5 mm × 28 mm (length × width × height) and its internal volume is about 3.8 cm. A home-made HreLIT mass spectrometer with three-stage vacuum system was built and the performance of HreLIT was characterized using reserpine solution and PPG standard solution. When the scan rate was 254 u/s, mass peak with FWHM of 0.14 u was achieved for ions with m/z 609, which corresponds to a mass resolution of 4350. The HreLIT was also operated at a low q value of 0.28 to extend its mass range. The experiment result showed a mass range of over 2800 u and the amplitude of radio frequency (rf) signal was only 1560 V (0-p). Three-stage tandem mass spectrometry was successfully performed in the HreLIT, and the collision-induced dissociation (CID) efficiencies of MS (CID of ions with m/z 609) and MS (CID of ions with m/z 448) were 78% and 59%, respectively. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A mesh-electrode linear ion trap (ME-LIT) mass analyzer was developed and its performance was primarily characterized. In conventional linear ion trap mass analyzers, the trapped ions are mass-selected and then ejected in a radial direction by a slot on a trap electrode. The presence of slots can strongly affect the electric field distribution in the ion trapping region and distort the mass analysis performance. To compensate for detrimental electric field effects, the slot is usually designed and fabricated to be as small as possible, and also has very high mechanical accuracy and symmetry. A ME-LIT with several mesh electrodes was built to compensate for the effects caused by slots. Each mesh electrode was fabricated from a plate electrode with a relatively large slot and the slot was covered with a conductive mesh. Our preliminary experimental results show that the ME-LIT could considerably diminish the detrimental electric field effects caused by slots, and increase the mass resolving power and ion detection efficiency. Even with 4-mm-wide slots, a mass resolution in excess of 600 was obtained using the ME-LIT. Mass resolution could be remarkably improved using mesh electrodes in ion traps with asymmetric electrodes. The stability diagram of the ME-LIT was mapped, and highly efficient tandem mass spectrometry was demonstrated. The ME-LIT was qualified as a LIT mass analyzer. The ME-LIT can improve the mass resolution and decrease the requirements of mechanical accuracy and symmetry of slots, so it shows potential for a wide range of practical uses. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A novel ion trap array (ITA) mass analyzer with six ion trapping and analyzing channels was investigated. It is capable of analyzing multiple samples simultaneously. The ITA was built with several planar electrodes made of stainless steel and 12 identical parallel zirconia ceramic substrates plated with conductive metal layers. Each two of the opposing ceramic electrode plates formed a boundary of an ion trap channel and six identical ion trapping and analyzing channels were placed in parallel without physical electrode between any two adjacent channels. The electric field distribution inside each channel was studied with simulation. The new design took the advantage of high precision machining attributable to the rigidity of ceramic, and the convenience of surface patterning technique. The ITA system was tested by using a two-channel electrospray ionization source, a multichannel simultaneous quadruple ion guide, and two detectors. The simultaneous analysis of two different samples with two adjacent ITA channels was achieved and independent mass spectra were obtained. For each channel, the mass resolution was tested. Additional ion trap functions such as mass-selected ion isolation and collision-induced dissociation (CID) were also tested. The results show that one ITA is well suited for multiple simultaneous mass analyses. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The Planar electrostatic ion trap expands the trapping space of the linear electrostatic ion trap, giving rise to higher tolerance to space charge. A rotational symmetrical design was made, which has a trapping field between two layers of concentric circular electrodes, and the ions are trapped to oscillate around the center plane between the electrodes. The oscillatory motions of the ions were simulated and the field distribution was optimized to achieve isochronous motion against energy spread in R, z, and φ directions. The image charge signal can be picked up by more than one circular electrode and using FFT the mass resolution for the optimized trap can reach 80,000 FWHM. While Fourier transform of the image charge signal generates many high harmonic peaks, the unwanted harmonic peaks can be eliminated by linear combination of image charge signals from multiple pick-up electrodes to give satisfactory results. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: Development of miniaturized ion trap (IT) mass analyzers for portable mass spectrometry has taken advantage of the latest technology in conventional machining and microfabrication. Researchers are now turning to new materials, such as polymers and ceramics, as well as alternative electrode shapes and arrangements to create the precisely-shaped electric fields needed for good performance on small-scale devices. Polymer-based construction allows lightweight structures, complex shapes and inexpensive production of small ITs. Simplified electrode arrangements, such as ITs made from two patterned ceramic plates, allow precise electric fields and simplified electrode alignment. [Copyright &y& Elsevier]

Abstract: This review describes recently presented instrumental set-ups for aerosol mass spectrometry (AMS), most being suitable for in-situ analysis. AMS allows the analysis of atmospheric aerosol particles within a short time interval and without sample pretreatment, and it is less sensitive to artifact formation than conventional sampling and analytical techniques. Although a quantitative measure of total organic loading can be obtained with some AMS instruments, they currently give only limited information on specific compounds. When the ionization technique produces a large number of fragments for a compound, it becomes impossible to track the original compound. Moreover, at present, there is no commercially available instrument capable of quantitative analysis of chemical compounds in ambient aerosol particles with diameters of 0.003–50μm and simultaneously offering short time resolution. We pay special attention to the technical and methodological challenges of AMS, whose benefits we demonstrate with selected applications. [Copyright &y& Elsevier]

Abstract: Reduced power operation of a mass analyzer with minimum loss of spectral resolution and mass range is desirable in portable instruments. Miniaturizing quadrupole-based ion traps can be especially worthwhile since the RF amplitude necessary for mass analysis scales with the square of the analyzer dimensions. The performance of a miniature, stainless steel, rectilinear ion trap (RIT) with dimensions of 1.66mm×1.43mm (x 0 and y 0 respectively) is characterized by sampling externally generated ions and performing mass analysis without benefit of differential pumping to simulate conditions in a miniature system. This system is capable of detecting analyte ions of up to m/z 1250 at operating voltages of 610V0-p (drive frequency of 1.105MHz), and with spectral resolution on the order of 2Th (FWHM) across the entire mass range. The ability to acquire structural information through tandem MS is also demonstrated. [Copyright &y& Elsevier]

Abstract: This paper presents a parallel magnetic sector mass analyzer design in which ions are simultaneously detected on a flat horizontal plane for a mass range of 1–260amu. Simulation results predict that second-order focusing can be achieved for several regions in the detected mass spectrum. The analyzer is predicted to have an average mass resolution limited by spherical aberration of 611 for an input angular spread of ±25mrad along its intrinsic focal plane, which when projected on a horizontal detector plane, drops to 371. For energy dispersion correction via the use of an electric sector, the average predicted mass resolution limited by spherical aberration (±25mrad angular spread) on the horizontal detector plane is 415. The predicted mass resolution limited by chromatic aberration is 592 where the energy spread is ±60eV around an emission energy of 2keV (±3%). A model based upon the magnetic scalar potential model is first used, and later checked by simulation that takes into account the effects of magnetic saturation. [Copyright &y& Elsevier]

Abstract: The evolution of high-irradiance laser-ionization time-of-flight mass spectrometry (LI-TOF-MS) mainly progressed following significant improvements in the laser source, the TOF mass analyzer and construction geometries. We summarize the main developments in LI-TOF-MS, including the instrumentation and the applications. We also present particular instruments that our group developed recently. [Copyright &y& Elsevier]

Abstract: We review the features and the potential of advanced mass spectrometry (MS) in proteomic research together with applications in detecting and identifying for food allergens. Reliable, sensitive methods tracing ingredients of or relevant specific biomarkers for allergenic food are required to comply with food-labeling legislation. Food allergens are identified by proteolytic digestion upon isolating proteins (bottom-up approach) or directly analyzing intact proteins and their fragmentation products (top-down approach). Advanced separation methods are needed for a higher degree of resolution in order to separate complex mixtures of peptides. Food allergens can be characterized and identified by fingerprinting peptide masses or peptide fragments combined with computer search of databases. We also discuss development of mass analyzers, hybrid multi-stage instruments (e.g., Q-TOF, TOF2 and LTQ-FT-ICR), featuring other types of tandem MS (MS2) experiments. [Copyright &y& Elsevier]

Abstract: This review focuses on recent developments and trends in liquid chromatography coupled to mass spectrometry, with a particular emphasis on tandem mass spectrometry and the new criteria established by the European Union for performing confirmatory analysis of veterinary drugs in animal-food products. The combination of liquid chromatography and tandem mass spectrometry allows unequivocal identification of traces of antibiotics and antibacterial agents in complex biological matrices, such as honey, eggs, milk and meat. The sensitivity of the coupling is particularly useful for confirming the presence of banned substances that require limits of detection as low as possible. [Copyright &y& Elsevier]

The charged particle mass analyzer with the poles of the cylindrical form and closed boundaries has been proposed. The expression for the distribution of the magnetic potential has been obtained in the analytical form. The basic parameters in the dispersion plane have been found for the first-order focusing on the angle. The conditions of the space focusing have been obtained when the source and detector are placed out of the magnetic field. The regimes with the three turns of the trajectory have been found. In this case the charged particles have the long path inside field. It results in the increasing of the linear mass dispersion and, consequently, in high resolution. [Copyright &y& Elsevier]

A new separator and mass analyzer, named MASHA (mass analyzer of super heavy atoms), has been designed at the Flerov Laboratory JINR Dubna to separate and measure masses of nuclei and molecules with precision better than 10−3. The set up can work in the wide mass range from A≈20 to A≈500, its mass acceptance is as large as ±2.8%. In particular, it allows unambiguous mass identification of super heavy nuclei with a resolution better than 1 amu at the level of 300 amu.Synthesized in nuclear reactions nuclides are emitted from an ECR ion source at energy E=40 kV and charge state Q=+1. Then they pass the following steps of separation and analysis: the first section of rough separation, the second section of separation and mass analysis and the final section of separation with a 90° electrostatic deflector. In the focal plane of the device, a focal plane detector determines positions (masses) of studied nuclei.Ion optics of the analyzer, optimized up to the second order, is considered. Description of its elements and subsystems is given. [Copyright &y& Elsevier]

This work demonstrates a novel approach to mass spectrometry using the "virtual-slit" created by the small, localized volume from which ions are generated by localized ionization techniques such as laser ionization of particles and surfaces, and spark ionization. That is, the volume in which the ions are generated creates a localized source of ions in much the same way as a slit that allows only ions from a specific cross sectional area to pass. As demonstrated in this work, the unique perfect focusing properties of a cycloidal mass analyzer can enable the localized ionization volume to function as a virtual-slit. In this manuscript, we provide a proof-of-concept (POC) demonstration of a virtual-slit cycloidal mass spectrometer (VS-CMS) consisting of a cycloidal mass analyzer, a laser ionization source, and an ion array detector. The laser is used to ionize either bulk or thin film samples of Cu, Ti, Ni, and Cr. Results indicate that the width of the peaks at the detector is the same as the laser spot size, validating the concept of virtual-slit focusing. Furthermore, the Ti and Cu ablated with each laser pulse is estimated at 60 and 140 fg, respectively, indicating that a very low detection limit is possible given the ability of the cycloidal mass analyzer to collect ions generated by laser ionization that have wide energy and angular dispersions. The VS-CMS concept has the potential to enable development of fieldable instruments for chemical, elemental, and isotopic analysis of organic and inorganic samples, that are relatively small compared to currently used laser ionization time-of-flight and laser ablation inductively coupled plasma mass spectrometers. [Display omitted] • First demonstration of a "virtual-slit" cycloidal mass analyzer (VS-CMS). • Virtual-slit focusing: ionization region size equals peak width on array detector. • Perfect focusing cycloidal mass analyzer enables virtual slit focusing. • VS-CMS proof of concept demonstrates isotope ratios and sensitivity to <100 fg. • VS-CMS can enable development of portable instruments for isotope ratio analysis. [ABSTRACT FROM AUTHOR]

Ion-optical and imaging properties are characterized for a multi-reflecting time-of-flight (MR-TOF) analyzer based on planar ion mirrors and lenses. Mass and spatial resolutions are numerically evaluated for a 1.3 m long MR-TOF analyzer with 10 m flight path. A spatial resolution of a few microns is predicted for smaller (1–4 mm2) fields of view. For larger (100 mm2) fields of view the spatial resolution degrades to sub-mm, which still may be used for the simultaneous mapping of array ion sources. The aberration limit of the mass resolving power remains above R m = 300 000 within 100 mm2 field of view and within 3% energy spread. [Display omitted] • Ion-optical concept of an imaging multi-reflection mirror-type TOF mass analyzer presented. • Realistic mass resolving power of 50 000–100 000 at 300 000 aberration limit. • Spatial resolution of 5 μm at 1–4 mm2 field of view. • Mapping of 100 mm2 field of view with 100 sources for a parallel multi-source mass analysis. [ABSTRACT FROM AUTHOR]

Abstract: Using the crossed molecular and electron beams technique and the mass-spectrometric analysis of the reaction products, electron-impact dissociative ionization of the sulfur hexafluoride molecule was studied within the incident electron energy range from threshold up to 150eV. The simultaneous production of the ion fragment pair was observed confirming the mechanism of intermediate doubly charged ion formation suggested earlier by several authors. The relative dissociative ionization cross sections were normalized to the absolute scale using known experimental data. [Copyright &y& Elsevier]

• Validated anthocyanin quantification methods have been collated and summarized. • Cyanidin-3-glucoside is not always the predominate anthocyanin present in fruits and vegetables. • Understanding of anthocyanin profiles is important for anthocyanin quantification. • The summarized results indicate variation in the anthocyanin extraction methods. Food composition data are challenged by data availability and quality. Anthocyanins are the bright colored pigments found in fruits and vegetables with growing evidence for health benefits. For the estimation of anthocyanin content in the foods, it is imperative to find an ideal analytical method. To quantify anthocyanin components, liquid chromatography-based methods are commonly used. This review addresses the variability of liquid chromatography (LC) mass spectrometry (MS) methods for the identification and quantification of anthocyanins. Published studies for all years until February 2020 reporting LC methods for anthocyanins in fruits and vegetables were screened from 7660 studies. Only 29 studies met the eligibility criteria of method type and of these, only 13 studies reported a validated LC method. A wide range of validation parameters were identified including specificity, calibration, stability, and limits of detection. Differences in the sampling amounts for extraction were observed in all of the included studies. The quantification of multiple anthocyanin types without their corresponding analytical standards was observed in eight studies. The included 13 studies used reverse phase liquid chromatography separation with C 18 type or similar stationary phases and acidified aqueous or acidified aqueous: organic (usually methanol or acetonitrile) binary gradient mobile phases. Although all of the studies used mass spectrometry for identification, ultraviolet absorbance quantification was often used in conjunction with a photo-diode array (DAD/PDA) detector using reference standards where available. Extraction and preparation of samples remains the key concern for analysis as the oxidative stability of anthocyanins are a major impediment for accurate quantification of the components in foods. This review provides a summary of validated LC methods to assist analysts and nutritionists in the quantification of anthocyanin food components as the nutrient profiles of foods are challenged by the variability of the analytical methods. [ABSTRACT FROM AUTHOR]

In this paper, a simulation study on tailoring the fields in planar ion trap geometries for making them suitable for mass analysis is presented. Two different planar trap geometries were considered: the first is a One-Sheet Ion Trap Geometry in which the ions are trapped off-plane and the second is a Two-Sheet Ion Trap Geometry in which the ions are trapped in between the two sheets. Both DC and RF potentials were used to trap ions. The fields were tailored to obtain linear trapping fields in these two geometries. This was done by splitting the central electrode into segments and applying suitable DC potentials to them. The potentials were computed using a least square method. The simulations were carried out considering a printed circuit board (PCB) with a Teflon base. The One-Sheet Ion Trap Geometry consists of five electrodes, of which the central electrode is segmented. In Two-Sheet Ion Trap Geometry, each sheet consists of three electrodes, of which the central electrode is segmented. The method outlined in the study is able to tailor fields to be linear as well as mildly superlinear. Image 1 • Two planar ion trap geometries are studied for their use as mass analyzers. • In each trap, some electrodes are split into segments. • The fields are tailored by applying suitable DC potentials to the segments. [ABSTRACT FROM AUTHOR]