Peabody, MA, United States
Peabody, MA, United States

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Han M.-G.,Brookhaven National Laboratory | Zhu Y.,Brookhaven National Laboratory | Wu L.,Brookhaven National Laboratory | Aoki T.,JEOL United States Inc. | And 5 more authors.
Advanced Materials | Year: 2013

Field-induced switching of ferroelectric domains with a topological vortex configuration is studied by atomic imaging and electrical biasing in an electron microscope, revealing the role of topological defects on the topologically-guided change of domain-wall pairs in a hexagonal manganite. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Block E.,University at Albany | Dane A.J.,JEOL United States Inc. | Thomas S.,University at Albany | Cody R.B.,JEOL United States Inc.
Journal of Agricultural and Food Chemistry | Year: 2010

Through the use of direct analysis in real time mass spectrometry (DART-MS), 2-propenesulfenic acid, an intermediate long postulated as being formed when garlic (Allium sativum) is crushed, has been detected for the first time and determined by mass spectrometric methods to have a half-life of <1 s at room temperature. Two other key intermediates, 2-propenesulfinic acid and diallyl trisulfane S-oxide, have also been detected for the first time in volatiles from crushed garlic, along with allicin and related thiosulfinates, allyl alcohol, sulfur dioxide, propene, and pyruvate as coproducts. A commercial dietary supplement containing garlic powder, which was sampled after crushing, was found to contain alliin, methiin, and S-allylcysteine and produced allicin upon addition of water. DART-MS detection of 1-butenesulfenic acid from the ornamental A. siculum is also reported. (Z)-Propanethial S-oxide (onion lachrymatory factor), absent in garlic, is found to be formed from crushed elephant garlic (Allium ampeloprasum), consistent with the classification of this plant as a closer relative of leek than of garlic. Mixtures of thiosulfinates, lachrymatory thial S-oxides, and related compounds are directly observed from crushed leek (Allium porrum) and Chinese chive (Allium tuberosum). Disulfanes and polysulfanes are detected only when the Allium samples are heated, consistent with earlier conclusions that these are not primary products from cut or crushed alliums. © 2010 American Chemical Society.


Lesiak A.D.,Albany State University | Cody R.B.,JEOL United States Inc. | Dane A.J.,JEOL United States Inc. | Musah R.A.,Albany State University
Analytical Chemistry | Year: 2015

Plant species identification based on the morphological features of plant parts is a well-established science in botany. However, species identification from seeds has largely been unexplored, despite the fact that the seeds contain all of the genetic information that distinguishes one plant from another. Using seeds of genus Datura plants, we show here that the mass spectrum-derived chemical fingerprints for seeds of the same species are similar. On the other hand, seeds from different species within the same genus display distinct chemical signatures, even though they may contain similar characteristic biomarkers. The intraspecies chemical signature similarities on the one hand, and interspecies fingerprint differences on the other, can be processed by multivariate statistical analysis methods to enable rapid species-level identification and differentiation. The chemical fingerprints can be acquired rapidly and in a high-throughput manner by direct analysis in real time mass spectrometry (DART-MS) analysis of the seeds in their native form, without use of a solvent extract. Importantly, knowledge of the identity of the detected molecules is not required for species level identification. However, confirmation of the presence within the seeds of various characteristic tropane and other alkaloids, including atropine, scopolamine, scopoline, tropine, tropinone, and tyramine, was accomplished by comparison of the in-source collision-induced dissociation (CID) fragmentation patterns of authentic standards, to the fragmentation patterns observed in the seeds when analyzed under similar in-source CID conditions. The advantages, applications, and implications of the chemometric processing of DART-MS derived seed chemical signatures for species level identification and differentiation are discussed. (Figure Presented). © 2015 American Chemical Society.


Cody R.B.,JEOL United States Inc. | Dane A.J.,JEOL United States Inc.
Rapid Communications in Mass Spectrometry | Year: 2014

RATIONALE The feasibility of using paper spray ionization as an ambient ionization method for inorganic analysis was investigated. METHODS Aqueous solutions were spotted onto paper triangles and high voltage was applied to induce electrospray. In-source collision-induced dissociation assisted in breaking up clusters to produce mass spectra dominated by atomic ions and their corresponding oxides and hydroxides and high-resolution exact mass measurements were used to identify atomic ions in the presence of organic interferences. RESULTS A feasibility test with a standard inductively coupled plasma mass spectrometry (ICP-MS) test mixture demonstrated detection of 21 of 23 elements as M+• or [M + OH]+. The two undetected elements (boron and lithium) were below the minimum detectable m/z setting for the time-of-flight mass spectrometer used for these experiments. Untreated filter paper showed residual contamination from group I and group II elements. Excellent linearity was observed over the concentration range 0.1-1000 ppm for nickel(II) nitrate solutions containing 10 ppm cobalt(II) nitrate as internal standard. The method was applied to the analysis of lead-free solder, a bismuth subsalicylate tablet, permanent magnet materials and lead chromate pigment in a three-cent US postage stamp issued in 1948. CONCLUSIONS Paper spray ionization was successfully applied to qualitative inorganic analysis. Quantitative analysis was shown to be possible with the use of internal standards. Initial detection limits were much higher than for comparable inductively coupled plasma and glow discharge methods, ranging from the high parts-per-billion range to the low parts-per-million range. The detection limits for some elements were limited at low levels by the presence of interferences that were not separated by the resolving power of the mass spectrometer. Despite these limitations, the simplicity and potential portability of paper spray may find some applications for elemental analysis. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.


Cody R.B.,JEOL United States Inc. | Dane A.J.,JEOL United States Inc.
Rapid Communications in Mass Spectrometry | Year: 2016

Rationale: Mass spectra were acquired with the Direct Analysis in Real Time (DART®) ion source for an amine-terminated polyether used as positive-ion mass reference standards and for several fluorinated materials commonly used as negative-ion reference standards for mass spectrometry. Methods: A commercial time-of-flight mass spectrometer equipped with a DART ion source was used for all measurements. Mass reference standards deposited onto the sealed end of a glass melting point tube were suspended in the DART gas stream for analysis. Results: A polyetheramine (Jeffamine® M-600) produced intense peaks corresponding to protonated molecules. Perfluorotributylamine (PFTBA), and perfluorotripentylamine, gave useful reference spectra for different m/z ranges. DART mass spectra of Ultramark 1621® resembled those previously reported for Fast Atom Bombardment (FAB) and Electrospray Ionization (ESI). Fomblin®Y, a fluorinated ether, was the most useful negative-ion reference standard of the materials tested. The material is commercially available, inexpensive, and provides reference peaks covering the m/z range 85 to >3000. Conclusions: Jeffamine-M600 was found to be a convenient alternative to polyethers such as polyethylene glycol (PEG) for DART positive-ion mass calibration. Fomblin Y was suitable for use as a negative-ion reference standard. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.


Cody R.B.,JEOL United States Inc. | Dane A.J.,JEOL United States Inc.
Journal of the American Society for Mass Spectrometry | Year: 2013

Large polarizable n-alkanes (approximately C18 and larger), alcohols, and other nonpolar compounds can be detected as negative ions when sample solutions are injected directly into the sampling orifice of the atmospheric pressure interface of the time-of-flight mass spectrometer with the direct analysis in real time (DART) ion source operating in negative-ion mode. The mass spectra are dominated by peaks corresponding to [M + O2]-•. No fragmentation is observed, making this a very soft ionization technique for samples that are otherwise difficult to analyze by DART. Detection limits for cholesterol were determined to be in the low nanogram range. © 2013 American Society for Mass Spectrometry.


Dane A.J.,JEOL United States Inc. | Cody R.B.,JEOL United States Inc.
Analyst | Year: 2010

5-Hydroxymethylfurfural (5-HMF) is a compound with the elemental composition C6H6O3 that is present in powdered milk. Protonated 5-HMF (calculated m/z 127.0395) has the same nominal m/z as protonated melamine (calculated m/z 127.0732) and can interfere with direct analysis of melamine in powdered milk. Tandem mass spectrometry and high-resolution mass spectrometry have been previously used to distinguish melamine from 5-HMF. An alternative approach is presented here that uses the direct analysis in real time (DART™) ion source operated with argon gas in combination with acetylacetone and pyridine reagent gases to selectively ionize melamine and eliminate the interference from 5-HMF. High-resolution/accurate mass data were used to verify the elimination of the 5-HMF interference and confirm the melamine elemental composition. With further refinement, this technique could lead to a rapid analysis method for screening large numbers of samples. © 2010 The Royal Society of Chemistry.


Patent
Jeol United States Inc. | Date: 2010-05-17

A method of producing analyte, analyte fragment, and/or analyte adduct ions for mass analysis comprises the steps of spraying a solvent at a surface bearing the analyte, directing desorbed analyte evolved from the surface into a region containing species which will ionize the analyte on collision, the ionizing region not including the surface bearing the analyte, and directing the ions formed in the ionizing region to the entrance to a mass analyzer.


Patent
JEOL United States INC. | Date: 2010-05-18

A method of inorganic analysis by mass spectrometry comprises treating a surface with a chelating reagent so that inorganic elements can be made volatile and desorbed directly from the surface, exposing the volume over the surface or a swab wiping the surface to a flow of metastable atoms and molecules at atmospheric pressure to ionize volatile compounds, and passing the ionized volatile compounds to a mass spectrometer or the like.


Patent
Jeol United States Inc. | Date: 2010-11-24

A method of inorganic analysis by mass spectrometry comprises treating a surface with a chelating reagent so that inorganic elements can be made volatile and desorbed directly from the surface, exposing the volume over the surface or a swab wiping the surface to a flow of metastable atoms and molecules at atmospheric pressure to ionize volatile compounds, and passing the ionized volatile compounds to a mass spectrometer or the like.

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