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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]

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]

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]

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]

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]