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Sample records for chromatography-ion trap mass

  1. [Determination of 21 fragrance allergens in toys by gas chromatography-ion trap mass spectrometry].

    Science.gov (United States)

    Lü, Qing; Zang, Qing; Bai, Hua; Li, Haiyu; Kang, Suyuan; Wang, Chao

    2012-05-01

    A method of gas chromatography-ion trap mass spectrometry (GC-IT-MS) was developed for the determination of 21 fragrance allergens in sticker toys, plush toys and plastic toys. The experimental conditions, such as sample pretreatment conditions, and the analytical conditions of GC-IT-MS, were optimized. The sticker toy samples and plush toy samples were extracted with acetone by ultrasonic wave, and the extracts were separated on an Agilent HP-1 MS column (50 m x 0.2 mm x 0.5 microm), then determined by IT-MS and quantified by external standard method. The plastic toy samples were extracted by the dissolution-precipitation approach, cleaned up with an Envi-carb solid phase extraction column and concentrated by rotary evaporation and nitrogen blowing, then determined by GC-IT-MS and quantified by external standard method. The calibration curves showed good linearity in the range of 0.002-50 mg/L with the correlation coefficients greater than 0.996 8. The limits of quantification (LOQ, S/N > 10) were 0.02-40 mg/kg. The average recoveries of the target compounds spiked in the sample at three concentration levels were in the range of 82.2%-110.8% with the relative standard deviations (RSDs) of 0.6%-10.5%. These results show that this method is accurate and sensitive for the qualitative and quantitative determination of the 21 fragrance allergens in the 3 types of toys.

  2. Silylation of acrylamide for analysis by solid-phase microextraction/gas chromatography/ion-trap mass spectrometry.

    Science.gov (United States)

    Lagalante, Anthony F; Felter, Matthew A

    2004-06-16

    A method for quantitative analysis of acrylamide has been developed for use with headspace solid-phase microextraction (SPME). In the method, acrylamide undergoes silylation with N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) to form the volatile N,O-bis(trimethylsilyl)acrylamide (BTMSA). Once formed, BTMSA is readily extracted from the headspace over the silylation reaction using a 100 microm poly(dimethylsiloxane) SPME fiber. A series of experiments was undertaken to optimize the amount of BSTFA, the silylation reaction temperature, the silylation reaction duration, and SPME sampling duration to maximize the analytical sensitivity for BTMSA. Acrylamide levels were quantified relative to a [13C3]-acrylamide internal standard using gas chromatography/ion-trap mass spectrometry (GC/MS) in the single ion monitoring mode. An analytical working curve was constructed and found to be linear over the 4 to 6700 ppb acrylamide range investigated with a limit of detection of 0.9 ppb. The native acrylamide levels of three commercial cereals were measured using the optimized analytical method. Quantitative standard additions of acrylamide to the cereal matrixes demonstrated complete recovery of the spiked acrylamide.

  3. Multiresidue analysis of 50 pesticides in grape, pomegranate, and mango by gas chromatography-ion trap mass spectrometry.

    Science.gov (United States)

    Savant, Rahul H; Banerjee, Kaushik; Utture, Sagar C; Patil, Sangram H; Dasgupta, Soma; Ghaste, Manoj S; Adsule, Pandurang G

    2010-02-10

    A selective and sensitive multiresidue analysis method is reported for simultaneous determination of 50 pesticides of different chemical classes in three commercially important fruits of different nature viz. grape, pomegranate, and mango. The sample preparation method involves extraction of a 10 g sample with 10 mL of ethyl acetate; cleanup by dispersive solid phase extraction with primary secondary amine (PSA, 25 mg) for grape and PSA + graphitized carbon black (25 + 5 mg) for pomegranate and mango; and determination by gas chromatography-ion trap mass spectrometry through multiple reaction monitoring (MRM). Sample preparation under acidified (pH 4) and cold (<4 degrees C) conditions, use of PTV-large volume injection (20 microL) through multibaffled liner and chromatographic separation on a short 10 m VF-5MS capillary column gave a satisfactory response for all of the analytes including relatively unstable compounds such as captan, captafol, folpet, endrine, and iprodione within 31.8 min. The limit of quantification (LOQ) of most of the compounds was

  4. Characterization of the synthesis of N,N-dimethyltryptamine by reductive amination using gas chromatography ion trap mass spectrometry.

    Science.gov (United States)

    Brandt, Simon D; Moore, Sharon A; Freeman, Sally; Kanu, Abu B

    2010-07-01

    The present study established an impurity profile of a synthetic route to the hallucinogenic N,N-dimethyltryptamine (DMT). The synthesis was carried out under reductive amination conditions between tryptamine and aqueous formaldehyde in the presence of acetic acid followed by reduction with sodium cyanoborohydride. Analytical characterization of this synthetic route was carried out by gas chromatography ion trap mass spectrometry using electron- and chemical-ionization modes. Methanol was employed as a liquid CI reagent and the impact of stoichiometric modifications on side-products formation was also investigated. Tryptamine 1, DMT 2, 2-methyltetrahydro-β-carboline (2-Me-THBC, 3), N-methyl-N-cyanomethyltryptamine (MCMT, 4), N-methyltryptamine (NMT, 5), 2-cyanomethyl-tetrahydro-β-carboline (2-CM-THBC, 6) and tetrahydro-β-carboline (THBC, 7) have been detected under a variety of conditions. Replacement of formaldehyde solution with paraformaldehyde resulted in incomplete conversion of the starting material whereas a similar replacement of sodium cyanoborohydride with sodium borohydride almost exclusively produced THBC instead of the expected DMT. Compounds 1 to 7 were quantified and the limits of detection were 28.4, 87.7, 21.5, 23.4, 41.1, 36.6, and 34.9 ng mL(-1), respectively. The limits of quantification for compounds 1 to 7 were 32.4, 88.3, 25.4, 24.6, 41.4, 39.9, and 37.0 µg mL(-1), respectively. Linearity was observed in the range of 20.8-980 µg mL(-1) with correlation coefficients > 0.99. The application holds great promise in the area of forensic chemistry where development of reliable analytical methods for the detection, identification, and quantification of DMT are crucial and also in pharmaceutical analysis where DMT might be prepared for use in human clinical studies.

  5. Development and validation of automatic HS-SPME with a gas chromatography-ion trap/mass spectrometry method for analysis of volatiles in wines.

    Science.gov (United States)

    Paula Barros, Elisabete; Moreira, Nathalie; Elias Pereira, Giuliano; Leite, Selma Gomes Ferreira; Moraes Rezende, Claudia; Guedes de Pinho, Paula

    2012-11-15

    An automated headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-ion trap/mass spectrometry (GC-IT/MS) was developed in order to quantify a large number of volatile compounds in wines such as alcohols, ester, norisoprenoids and terpenes. The procedures were optimized for SPME fiber selection, pre-incubation temperature and time, extraction temperature and time, and salt addition. A central composite experimental design was used in the optimization of the extraction conditions. The volatile compounds showed optimal extraction using a DVB/CAR/PDMS fiber, incubation of 5 ml of wine with 2g NaCl at 45 °C during 5 min, and subsequent extraction of 30 min at the same temperature. The method allowed the identification of 64 volatile compounds. Afterwards, the method was validated successfully for the most significant compounds and was applied to study the volatile composition of different white wines.

  6. Determination of specific neuropeptides modulation time course in a rat model of osteoarthritis pain by liquid chromatography ion trap mass spectrometry.

    Science.gov (United States)

    Ferland, Catherine E; Pailleux, Floriane; Vachon, Pascal; Beaudry, Francis

    2011-12-01

    Animal models are useful to evaluate pharmacological therapies to alleviate joint pain. The present study characterized central neuropeptides modulation in the monoiodoacetate (MIA) rat model. Animals receiving a single 3mg MIA injection were euthanized at 3, 7, 14, 21 and 28 days post injection. Spinal cords were analyzed by liquid chromatography ion trap mass spectrometry. Up-regulations of the calcitonin gene-related peptide and substance P were observed starting on days 7 and 28 respectively, whereas big dynorphin(₁₋₃₂) content decreased significantly on day 14 in comparison to control animals (P<0.05). Preclinical drug evaluations using this model should be conducted between 7 and 21 days post injection when the lesions resemble most to human osteoarthritis.

  7. A selective and sensitive method for quantitation of lysergic acid diethylamide (LSD) in whole blood by gas chromatography-ion trap tandem mass spectrometry.

    Science.gov (United States)

    Libong, Danielle; Bouchonnet, Stéphane; Ricordel, Ivan

    2003-01-01

    A gas chromatography-ion trap tandem mass spectrometry (GC-ion trap MS-MS) method for detection and quantitation of LSD in whole blood is presented. The sample preparation process, including a solid-phase extraction step with Bond Elut cartridges, was performed with 2 mL of whole blood. Eight microliters of the purified extract was injected with a cold on-column injection method. Positive chemical ionization was performed using acetonitrile as reagent gas; LSD was detected in the MS-MS mode. The chromatograms obtained from blood extracts showed the great selectivity of the method. GC-MS quantitation was performed using lysergic acid methylpropylamide as the internal standard. The response of the MS was linear for concentrations ranging from 0.02 ng/mL (detection threshold) to 10.0 ng/mL. Several parameters such as the choice of the capillary column, the choice of the internal standard and that of the ionization mode (positive CI vs. EI) were rationalized. Decomposition pathways under both ionization modes were studied. Within-day and between-day stability were evaluated.

  8. Detection of lysergic acid diethylamide (LSD) in urine by gas chromatography-ion trap tandem mass spectrometry.

    Science.gov (United States)

    Sklerov, J H; Kalasinsky, K S; Ehorn, C A

    1999-10-01

    A confirmatory method for the detection and quantitation of lysergic acid diethylamide (LSD) is presented. The method employs gas chromatography-tandem mass spectrometry (GC-MS-MS) using an internal ionization ion trap detector for sensitive MS-MS-in-time measurements of LSD extracted from urine. Following a single-step solid-phase extraction of 5 mL of urine, underivatized LSD can be measured with limits of quantitation and detection of 80 and 20 pg/mL, respectively. Temperature-programmed on-column injections of urine extracts were linear over the concentration range 20-2000 pg/mL (r2 = 0.999). Intraday and interday coefficients of variation were LSD-positive samples in this laboratory. Comparisons with alternate GC-MS methods and extraction procedures are discussed.

  9. Characterization of underivatized lipid biomarkers from microorganisms with pyrolysis short-column gas chromatography/ion trap mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Snyder, A.P. (Army Chemical Research, Aberdeen Proving Ground, MD (USA)); McClennen, W.H.; Dworzanski, J.P.; Meuzelaar, H.L.C. (Univ. of Utah, Salt Lake City (USA))

    1990-12-01

    A microvolume Curie-point pyrolysis short-column (5 m) gas chromatography/mass spectrometry (Py-Gc/MS) procedure was developed for the characterization of various lipid moieties in microorganisms. High linear flow rates (approximately 175 cm/s) characterized the GC conditions in order to effect an efficient chromatographic transfer and elution of the underivatized diglycerides and monoglycerides, and small modifications were necessary to the ion trap MS system in order for it to accommodate the relatively high gas load. During a typical analysis run anhydrodiacylglycerides eluted within a 5-6-min time frame. Gram-positive bacilli and Gram-negative species were differentiated from each other by the pyrolysis patterns of their lipid components. In spite of the complexity of the analyte, a straightforward visual analysis was achieved with the aid of simple computerized data display procedures. These procedures included examination of (1) total ion current (TIC) profiles of the lipid region of the reconstructed chromatogram, (2) the integrated mass spectrum of this region, (3) selected reconstructed ion chromatograms (RICs), (4) RIC intensity distributions, and (5) corresponding mass spectra. An appealing aspect of the lipid data reduction procedure is that most of it can be accomplished visually without requiring computerized pattern recognition techniques.

  10. Determination of trace levels of herbicides and their degradation products in surface and ground waters by gas chromatography/ion-trap mass spectrometry

    Science.gov (United States)

    Pereira, W.E.; Rostad, C.E.; Leiker, T.J.

    1990-01-01

    A rapid, specific and highly sensitive method is described for the determination of several commonly used herbicides and their degradation products in surface and ground waters by using gas chromatography/ion-trap mass spectrometry. The compounds included atrazine, and its degradation products desethylatrazine and desisopropylatrazine; Simazine; Cyanazine; Metolachlor; and alachlor and its degradation products, 2-chloro-2', 6'-diethylacetanilide, 2-hydroxy-2', 6'-diethylacetanilide and 2,6-diethylaniline. The method was applied to surface-water samples collected from 16 different stations along the lower Mississippi River and its major tributaries, and ground-water samples beneath a cornfield in central Nebraska. Average recovery of a surrogate herbicide, terbuthylazine, was greater than 99%. Recoveries of the compounds of interest from river water spiked at environmental levels are also presented. Full-scan mass spectra of these compounds were obtained on 1 ng or less of analyte. Data were collected in the full-scan acquisition mode. Quantitation was based on a single characteristic ion for each compound. The detection limit was 60 pg with a signal-to-noise ratio of greater than 10:1.

  11. Suitability of selective pressurized liquid extraction combined with gas chromatography-ion-trap tandem mass spectrometry for the analysis of polybrominated diphenyl ethers.

    Science.gov (United States)

    Losada, S; Parera, J; Abalos, M; Abad, E; Santos, F J; Galceran, M T

    2010-09-23

    A one-step extraction and clean-up method using pressurized liquid extraction (PLE) (selective PLE) combined with gas chromatography-ion-trap tandem mass spectrometry (GC-ITMS-MS) was evaluated for the analysis of polybrominated diphenyl ethers (from tri- to hepta-PBDEs) at low concentrations in fish and shellfish samples. To this end, the performance of an on-line PLE extraction/clean-up method and of a classical Soxhlet extraction and clean-up method using a multi-layer modified silica column were compared. The two sample treatment methods provided similar results, although an important reduction in the sample treatment time (40 min per sample) was achieved using the selective PLE method. In addition, the suitability of the PLE combined with GC-ITMS-MS method was evaluated by comparing the results obtained in the analysis of fish samples with those obtained by gas chromatography-high resolution mass spectrometry (GC-HRMS). Good agreement between both techniques was obtained with differences between the mean values of less than 16%. The selective PLE method coupled to GC-ITMS-MS produced accurate results for PBDE determination with low limits of detection (1.0-16.8 pg g(-1) wet weight) and quantification (3.1-51 pg g(-1) wet weight) as well as good precision (RSD<16%). This method has been applied to the analysis of PBDEs in fish and shellfish samples collected at fish markets in Catalonia (NE Spain).

  12. Identification and quantification of active alkaloids in Catharanthus roseus by liquid chromatography-ion trap mass spectrometry.

    Science.gov (United States)

    Chen, Qinhua; Zhang, Wenpeng; Zhang, Yulin; Chen, Jing; Chen, Zilin

    2013-08-15

    Catharanthus roseus is an important dicotyledonous medicinal plant that produces anticancer compounds. The active alkaloids vinblastine, vindoline, ajmalicine, catharanthine, and vinleurosine were identified by direct-injection ion trap-mass spectrometry (IT-MS) for collecting MS(1-2) spectra. The determinations of five alkaloids were accomplished by liquid chromatography (LC) with UV and MS detections. The analytes provided good signals corresponding to the protonated molecular ions [M+H](+) and product ions. The precursor ions and product ions for quantification of vinblastine, vindoline, ajmalicine, catharanthine, and vinleurosine were m/z 825→807, 457→397, 353→144, 337→144 and 809→748 by LC-IT-MS, respectively. Two methods were used to evaluate a number of validation characteristics (repeatability, LOD, calibration range, and recovery). MS provided a high selectivity and sensitivity for determination of five alkaloids in positive mode. After optimisation of the methods, separation, identification and quantification of the five components in C. roseus were comprehensively accomplished by HPLC with UV and MS detection.

  13. Generic detection of basic taxoids in wood of European Yew (Taxus baccata) by liquid chromatography-ion trap mass spectrometry.

    Science.gov (United States)

    Kite, Geoffrey C; Rowe, Emily R; Veitch, Nigel C; Turner, Jill E; Dauncey, Elizabeth A

    2013-02-01

    The occurrence of the cardiotoxin taxine (comprising taxine B and several other basic taxoids) in leaves of Taxus baccata L. (European yew) is well known and has led to public concerns about the safety of eating or drinking from utensils crafted from the wood of this poisonous species. The occurrence of basic taxoids in the heartwood of T. baccata had not been examined in detail, although the bark is known to contain 2'β-deacetoxyaustrospicatine. Initial examination of heartwood extracts for 2'β-deacetoxyaustrospicatine by liquid chromatography-mass spectrometry (LC-MS) revealed the presence of this basic taxoid at about 0.0007% dry weight, using a standard isolated from bark. Analyses for taxine B, however, proved negative at the extract concentration analysed. Observing other basic taxoids within the heartwood extracts was facilitated by developing generic LC-MS methods that utilised a fragment arising from the N-containing acyl group of basic taxoids as a reporter ion. Of the various MS strategies available on a hybrid ion trap-orbitrap instrument that allowed observation of this reporter ion, combining all-ion collisions with high resolution ion filtering by the orbitrap was most effective, both in terms of the number of basic taxoids detected and sensitivity. Numerous basic taxoids, in addition to 2'β-deacetoxyaustrospicatine, were revealed by this method in heartwood extracts of T. baccata. Red wine readily extracted the basic taxoids from heartwood while coffee extracted them less efficiently. Contamination with basic taxoids could also be detected in soft cheese that had been spread onto wood. The generic LC-MS method for detecting basic taxoids complements specific methods for detecting taxine B when investigating yew poisoning cases in which the analysis of complex extracts may be required or taxine B has not been detected.

  14. Analysis and comparison of glucocerebroside species from three edible sea cucumbers using liquid chromatography-ion trap-time-of-flight mass spectrometry.

    Science.gov (United States)

    Xu, Jie; Duan, Jingjing; Xue, Changhu; Feng, Tingyu; Dong, Ping; Sugawara, Tatsuya; Hirata, Takashi

    2011-11-23

    Sphingolipids constitute a highly diverse and complex class of molecules and exhibit important physiological functions. Glucocerebrosides are anticipated to play a positive role in human nutrition. In this study, complicated glucocerebrosides from three specimens of edible sea cucumbers, specifically, Acaudina molpadioides, Cucumaria frondosa, and Apostichopus japonicus, were rapidly identified using liquid chromatography-ion trap-time-of-flight mass spectrometry (LCMS-IT-TOF), which is a powerful analysis tool. [M + H](+), [M + Na](+), and [M + H - H(2)O](+) in positive electrospray ionization (ESI) mode were used for MS/MS analysis to obtain product ion spectra. Various long-chain bases of glucocerebrosides were found in these sea cucumbers. Two of the most common long-chain bases were 2-amino-1,3-dihydroxy-4-heptadecene (d17:1) and 4,8-sphingadienine (d18:2), which were acylated to form saturated and monounsaturated nonhydroxy and monohydroxy fatty acids with 18-25 carbon atoms. The glucocerebroside molecular species were the most complicated in the sea cucumber C. frondosa and were the simplest in the sea cucumber A. molpadioides.

  15. [Fast screening of 24 sedative hypnotics illegally added in improving sleep health foods by high performance liquid chromatography-ion trap mass spectrometry].

    Science.gov (United States)

    Lu, Li; Gong, Xu; Tan, Li

    2015-03-01

    A fast screening method was established for the simultaneous determination of 24 sedative hypnotics illegally added in improving sleep health foods by high performance liquid chromatography-ion trap mass spectrometry (HPLC-IT MS). The method was based on the sonication assisted extraction of the improving sleep health food samples using methanol. The extract was then filtrated with 0.45 µm filter membrane and the filtrate was separated on a Phenomenex Luna C18 column with isocratic elution at a flow rate of 0.3 mL/min. A binary mobile phase was 0.05% (v/v) formic acid (solvent A)-methanol/acetonitrile (15:25, v/v, solvent B). The electrospray ionization (ESI) source in positive ion mode or negative ion mode was used to scan MS1-MS3 spectra for the 24 sedative hypnotics. The MS2 and MS3 spectra were used for qualitative analysis of samples. The calibration graphs were linear in their concentration ranges with the correlation coefficients (r2) more than 0.999. The limits of detection (LODs) were 4.0-446.6 µg/L. The recoveries for all the drugs in the improving sleep health foods were 88.6%-110.3% with the relative standard deviations no more than 9.8% at three spiked levels. Twenty-seven batches of the improving sleep health foods were tested. Melatonin was found in eighteen batches. The method is fast, specific, sensitive, easy and suitable for fast screening of 24 sedative hypnotics illegally added in improving sleep health foods.

  16. Determination of N,N-dimethyltryptamine in beverages consumed in religious practices by headspace solid-phase microextraction followed by gas chromatography ion trap mass spectrometry.

    Science.gov (United States)

    Gaujac, Alain; Dempster, Nicola; Navickiene, Sandro; Brandt, Simon D; de Andrade, Jailson Bittencourt

    2013-03-15

    A novel analytical approach combining solid-phase microextraction (SPME)/gas chromatography ion trap mass spectrometry (GC-IT-MS) was developed for the detection and quantification N,N-dimethyltryptamine (DMT), a powerful psychoactive indole alkaloid present in a variety of South American indigenous beverages, such as ayahuasca and vinho da jurema. These particular plant products, often used within a religious context, are increasingly consumed throughout the world following an expansion of religious groups and the availability of plant material over the Internet and high street shops. The method described in the present study included the use of SPME in headspace mode combined GC-IT-MS and included the optimization of the SPME procedure using multivariate techniques. The method was performed with a polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber in headspace mode (70 min at 60 °C) which resulted in good precision (RSD<8.6%) and accuracy values (71-109%). Detection and quantification limits obtained for DMT were 0.78 and 9.5 mg L(-1), respectively and good linearity (1.56-300 mg L(-1), r(2)=0.9975) was also observed. In addition, the proposed method showed good robustness and allowed for the minimization of sample manipulation. Five jurema beverage samples were prepared in the laboratory in order to study the impact of temperature, pH and ethanol on the ability to extract DMT into solution. The developed method was then applied to the analysis of twelve real ayahuasca and vinho da jurema samples, obtained from Brazilian religious groups, which revealed DMT concentration levels between 0.10 and 1.81 g L(-1).

  17. Identification and characterization of supercritical fluid extracts of Rhizoma Chuanxiong by high performance liquid chromatography ion trap mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    Teng Jiuwei; Chen Hongwei; Li Deliang; Luo Andong

    2006-01-01

    The main constituents,senkyunolide A,Zligustilide,neocnidilide,3-butylphthalide,and ligustilide dimers,in supercritical CO2 fluid extracts of Rhizoma Chuanxiong,a popular Chinese traditional medicine,have been identified and characterized by high performance liquid chromatography tandem mass spectrometry.Separations were carded out on an Agilent (ECLIPSE XDB) C18 analytical column by gradient elution with 0.25% acetic acid and methanol (containing 0.25% acetic acid).An Agilent 1100 series LC/MSD XCT system was operated under positive ESI and auto MS/MS modes for mass spectrometric analysis.Collision-induced dissociation (CID) fragmentations of these phthalides have been investigated and elucidated.Phthalides have primarily undergone two ESI CID pathways:side-chain cleavage with losses of alkenes and ring-opening with eliminations of H2O followed by losses of CO.Direct neutral loss of CO has not been observed.Sodium adduct ions have demonstrated completely different CID pathways.

  18. Determination of non-ionic polyethoxylated surfactants in wastewater and river water by mixed hemimicelle extraction and liquid chromatography-ion trap mass spectrometry.

    Science.gov (United States)

    Cantero, Manuel; Rubio, Soledad; Pérez-Bendito, Dolores

    2005-03-04

    The capability of hemimicelles-based solid phase extraction (SPE)/liquid chromatography/atmospheric pressure chemical ionisation in positive mode, ion trap mass spectrometry (LC/(APCl+-IT)-MS) for the concentration, separation and quantitation of non-ionic surfactants has been investigated. Concentration was based on the formation of mixed aggregates of analytes [alkylphenol ethoxylates (APE, octyl and nonyl) and alkyl ethoxylates (AE, C12-C16)] with the anionic surfactant sodium dodecyl sulphate (SDS) that is adsorbed on alumina. Parameters affecting SPE were investigated on the basis that hemimicelles are dynamic entities in equilibrium with the aqueous phase. The performance of ion trap mass spectrometry for MS and MS/MS quantitation of non-ionic homologues was assessed. Recoveries of analytes from wastewater influent and effluent and river water samples ranged between 91 and 98% and were found independent on the length of the alkyl chain under the optimised conditions. Anionic surfactants did not interfere to the levels found in environmental samples. The detection limits ranged between 14 and 111 ng/l for wastewater influent, 10 and 40 for wastewater effluent and 4 and 35 for river water, after concentration of 250, 500 and 750 ml of sample, respectively. The approach was applied to the determination of AE and APE in influent and effluent samples from four wastewater treatment plants and four river samples. The concentrations of individual non-ionic surfactants found ranged between 0.3 and 373 microg/l.

  19. Structural elucidation of biologically active neomycin N-octyl derivatives in a regioisomeric mixture by means of liquid chromatography/ion trap time-of-flight mass spectrometry.

    Science.gov (United States)

    Giera, Martin; de Vlieger, Jon S B; Lingeman, Henk; Irth, Hubertus; Niessen, Wilfried M A

    2010-05-30

    Structural elucidation of six regioisomers of mono-N-octyl derivatized neomycin is achieved using MS(n) (up to n = 4) on an ion trap time-of-flight (IT-TOF) instrument equipped with electrospray ionization. The mixture of six derivatized neomycin analogues was generated by reductive amination in a shotgun synthetic approach. In parallel to the liquid chromatography/mass spectrometry (LC/MS) detection, the antibacterial activity of the neomycin regioisomers was tested by post-column addition of buffer and bacterial inocula, subsequent microfractionation of the resulting mixture, incubation, and finally a chemiluminescence-based bioactivity measurement based on the production of bacterial ATP. The MS-based high-resolution screening approach described can be applied in medicinal chemistry to help in designing and producing new antibiotic substances, which is particularly challenging due to the high functionality of most antibiotic substances, therefore requiring advanced (hyphenated) separation and detection techniques for compound mixtures.

  20. Analysis of polychlorinated dibenzo-p-dioxins, dibenzofurans and dioxin-like polychlorinated biphenyls in vegetable oil samples by gas chromatography-ion trap tandem mass spectrometry.

    Science.gov (United States)

    Malavia, J; Abalos, M; Santos, F J; Abad, E; Rivera, J; Galceran, M T

    2007-05-18

    Gas chromatography coupled to ion trap tandem mass spectrometry (CG-MS-MS) has been evaluated for the analysis of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs) in vegetable oil samples containing different concentration levels (0.2-6 pg WHO-TEQ g(-1) for both PCDD/Fs and dl-PCBs) of the 29 toxic congeners of PCDD/F and dioxin-like PCBs. The effect of potential interfering compounds such as polychlorinated naphthalenes (PCNs), polychlorinated biphenyls (PCBs) and polychlorinated diphenylethers (PCDEs) on the quantification of mono-ortho PCBs has been investigated. In addition, the influence of the clean-up procedure on the final determination by CG-MS-MS was studied, showing that the quality of the results depends to a great extent on this analytical step. Quality parameters have been established and good precisions (CV: 3-19%) and low limits of detection for PCDD/Fs (0.04-0.20 pg g(-1) oil) and dl-PCBs (0.08-0.64 pg g(-1) oil) were obtained. The method was validated by a comparison of the CG-MS-MS results with those obtained by GC-HRMS.

  1. High performance liquid chromatography/ion-trap mass spectrometry for separation and simultaneous determination of ethynylestradiol, gestodene, levonorgestrel, cyproterone acetate and desogestrel.

    Science.gov (United States)

    Matejícek, David; Kubán, Vlastimil

    2007-04-11

    A fast and highly sensitive high performance liquid chromatographic/ion-trap mass spectrometric method (LC/MS) has been developed for simultaneous determination of ethynylestradiol (EE2), gestodene (GES), levonorgestrel (LNG), cyproterone acetate (CPA) and desogestrel (DES). Among three types of sorbents tested (C8, C18 and phenyl) from two suppliers, the best separation was achieved on reverse phase Zorbax SB-Phenyl column using aqueous methanol as a mobile phase. A linear gradient profile from 70 up to 100% (v/v) in 7th min, kept constant at 100% up to 10th min and followed by a negative gradient to 70% of methanol up to 12th min was used for elution. Applicability of electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) and influence of the mobile phase composition, its flow rate, capillary/vaporizer temperature of API source and in-source fragmentor voltage ionization are discussed. The on-column limits of quantification (10S/N) were 300 pg of EE2, 14 pg of GES and LNG, 4 pg of CPA and 960 pg of DES per injection (1 microL) using APCI with data collection in selected ion monitoring (SIM) mode. The analytical performance of the method was evaluated using the determination of EE2, GES, LNG, CPA and DES in contraceptives and river water samples.

  2. Investigation of Symphytum cordatum alkaloids by liquid-liquid partitioning, thin-layer chromatography and liquid chromatography-ion-trap mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Mroczek, Tomasz [Department of Pharmacognosy with Medicinal Plants Laboratory, Medical University, 1 Chodzki St., 20-093 Lublin (Poland)]. E-mail: tmroczek@pharmacognosy.org; Ndjoko-Ioset, Karine [Laboratoire de Pharmacognosie et Phytochimie, Ecole de Pharmacie Geneve-Lausanne, Universite de Geneve, Quai Ernest-Ansermet 30, CH-1211 Geneva 4 (Switzerland); Glowniak, Kazimierz [Department of Pharmacognosy with Medicinal Plants Laboratory, Medical University, 1 Chodzki St., 20-093 Lublin (Poland); Mietkiewicz-Capala, Agnieszka [Department of Pharmacognosy with Medicinal Plants Laboratory, Medical University, 1 Chodzki St., 20-093 Lublin (Poland); Hostettmann, Kurt [Laboratoire de Pharmacognosie et Phytochimie, Ecole de Pharmacie Geneve-Lausanne, Universite de Geneve, Quai Ernest-Ansermet 30, CH-1211 Geneva 4 (Switzerland)

    2006-05-04

    From the alkalised crude extract of Symphytum cordatum (L.) W.K. roots, pyrrolizidine alkaloids (PAs) were extracted as free tertiary bases and polar N-oxides in a merely one-step liquid-liquid partitioning (LLP) in separation funnel and subsequently pre-fractionated by preparative multiple-development (MD) thin-layer chromatography (TLC) on silica gel plates. In this way three alkaloid fractions of different polarities and retention on silica gel plates were obtained as: the most polar N-oxides of the highest retention, the tertiary bases of medium retention, and diesterified N-oxides of the lowest retention. The former fraction was reduced into free bases by sodium hydrosulfite and purified by LLP on Extrelut-NT3 cartridge. It was further analysed together with the two other fractions by high-performance liquid chromatography (HPLC)-ion-trap mass spectrometry with atmospheric pressure chemical ionization (APCI) interface on XTerra C{sub 18} column using a gradient elution. Based on MS {sup n} spectra, 18 various alkaloids have been tentatively determined for the first time in this plant as the following types of structure: echimidine-N-oxide (three diasteroisomers), 7-sarracinyl-9-viridiflorylretronecine (two diasteroisomers), echimidine (two diasteroisomers), lycopsamine (two diasteroisomers), dihydroechinatine-N-oxide, dihydroheliospathuline-N-oxide, lycopsamine-N-oxide (three diasteroisomers), 7-acetyllycopsamine-N-oxide, symphytine-N-oxide (two diasteroisomers) and 2'',3''-epoxyechiumine-N-oxide.

  3. Rapid and sensitive gas chromatography ion-trap mass spectrometry method for the determination of tobacco specific N-nitrosamines in secondhand smoke

    Energy Technology Data Exchange (ETDEWEB)

    SLEIMAN, Mohamad; MADDALENA, Randy L.; GUNDEL, Lara A.; DESTAILLATS, Hugo

    2009-07-01

    Tobacco-specific nitrosamines (TSNAs) are some of the most potent carcinogens in tobacco and cigarette smoke. Accurate quantification of these chemicals is needed to help assess public health risks. We developed and validated a specific and sensitive method to measure four TSNAs in both the gas- and particle-phase of secondhand smoke (SHS) using gas chromatography and ion-trap tandem mass spectrometry,. A smoking machine in an 18-m3 room-sized chamber generated relevant concentrations of SHS that were actively sampled on Teflon coated fiber glass (TCFG) filters, and passively sampled on cellulose substrates. A simple solid-liquid extraction protocol using methanol as solvent was successfully applied to both filters with high recoveries ranging from 85 to 115percent. Tandem MS parameters were optimized to obtain the best sensitivity in terms of signal to-noise ratio (S/N) for the target compounds. For each TSNA, the major fragmentation pathways as well as ion structures were elucidated and compared with previously published data. The method showed excellent performances with a linear dynamic range between 2 and 1000 ng mL-1, low detection limits (S/N> 3) of 30-300 pg.ml-1 and precision with experimental errors below 10percent for all compounds. Moreover, no interfering peaks were observed indicating a high selectivity of MS/MS without the need for a sample clean up step. The sampling and analysis method provides a sensitive and accurate tool to detect and quantify traces of TSNA in SHS polluted indoor environments.

  4. Quantitative determination of sotolon, maltol and free furaneol in wine by solid-phase extraction and gas chromatography-ion-trap mass spectrometry.

    Science.gov (United States)

    Ferreira, Vicente; Jarauta, Idoia; López, Ricardo; Cacho, Juan

    2003-08-22

    A method for the analytical determination of sotolon [4,5-dimethyl-3-hydroxy-2(5H)-furanone], maltol [3-hydroxy-2-methyl-4H-pyran-4-one] and free furaneol [2,5-dimethyl-4-hydroxy-3(2H)-furanone] in wine has been developed. The analytes are extracted from 50 ml of wine in a solid-phase extraction cartridge filled with 800 mg of LiChrolut EN resins. Interferences are removed with 15 ml of a pentane-dichloromethane (20:1) solution, and analytes are recovered with 6 ml of dichloromethane. The extract is concentrated up to 0.1 ml and analyzed by GC-ion trap MS. Maltol and sotolon were determined by selected ion storage of ions in the m/z ranges 120-153 and 79-95, using the ions m/z 126 and 83 for quantitation, respectively. Furaneol was determined by non-resonant fragmentation of the m/z 128 mother ion and subsequent analysis of the m/z 81 ion. The detection limits of the method are in all cases between 0.5 and 1 microg l(-1), well below the olfactory thresholds of the compounds. The precision of the method is in the 4-5% range for levels in wine around 20 microg l(-1). Linearity holds at least up to 400 microg l(-1), and is satisfactory in all cases. The recoveries of maltol and sotolon are constant (70 and 64%, respectively) and do not depend on the type of wine. On the contrary, in the case of furaneol, red wines show constant and high recoveries (97%), while the recoveries on white wines range between 30 and 80%. Different experiments showed that this behavior is probably due to the existence of complexes formed between furaneol and sulphur dioxide or catechols. Sensory experiments confirmed that the complexed forms found in white wines are not perceived by orthonasal olfaction, and that the furaneol determined by the method can be considered as the free and odor-active fraction.

  5. The quantitation of 2-oxo-3-hydroxy lysergic acid diethylamide (O-H-LSD) in human urine specimens, a metabolite of LSD: comparative analysis using liquid chromatography-selected ion monitoring mass spectrometry and liquid chromatography-ion trap mass spectrometry.

    Science.gov (United States)

    Poch, G K; Klette, K L; Anderson, C

    2000-04-01

    This paper compares the potential forensic application of two sensitive and rapid procedures (liquid chromatography-mass spectrometry and liquid chromatography-ion trap mass spectrometry) for the detection and quantitation of 2-oxo-3-hydroxy lysergic acid diethylamide (O-H-LSD) a major LSD metabolite. O-H-LSD calibration curves for both procedures were linear over the concentration range 0-8,000 pg/mL with correlation coefficients (r2) greater than 0.99. The observed limit of detection (LOD) and limit of quantitation (LOQ) for O-H-LSD in both procedures was 400 pg/mL. Sixty-eight human urine specimens that had previously been found to contain LSD by gas chromatography-mass spectrometry were reanalyzed by both procedures for LSD and O-H-LSD. These specimens contained a mean concentration of O-H-LSD approximately 16 times higher than the LSD concentration. Because both LC methods produce similar results, either procedure can be readily adapted to O-H-LSD analysis for use in high-volume drug-testing laboratories. In addition, the possibility of significantly increasing the LSD detection time window by targeting this major LSD metabolite for analysis may influence other drug-free workplace programs to test for LSD.

  6. Peptide profiling of Internet-obtained Cerebrolysin using high performance liquid chromatography - electrospray ionization ion trap and ultra high performance liquid chromatography - ion mobility - quadrupole time of flight mass spectrometry.

    Science.gov (United States)

    Gevaert, Bert; D'Hondt, Matthias; Bracke, Nathalie; Yao, Han; Wynendaele, Evelien; Vissers, Johannes Petrus Cornelis; De Cecco, Martin; Claereboudt, Jan; De Spiegeleer, Bart

    2015-09-01

    Cerebrolysin, a parenteral peptide preparation produced by controlled digestion of porcine brain proteins, is an approved nootropic medicine in some countries. However, it is also easily and globally available on the Internet. Nevertheless, until now, its exact chemical composition was unknown. Using high performance liquid chromatography (HPLC) coupled to ion trap and ultra high performance liquid chromatography (UHPLC) coupled to quadrupole-ion mobility-time-of-flight mass spectrometry (Q-IM-TOF MS), combined with UniProt pig protein database search and PEAKS de novo sequencing, we identified 638 unique peptides in an Internet-obtained Cerebrolysin sample. The main components in this sample originate from tubulin alpha- and beta-chain, actin, and myelin basic protein. No fragments of known neurotrophic factors like glial cell-derived neurotrophic factor (GDNF), neurotrophin nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and ciliary neurotrophic factor (CNTF) were found, suggesting that the activities reported in the literature are likely the result of new, hitherto unknown cryptic peptides with nootropic properties.

  7. 气相色谱-离子阱质谱联用测定玩具中8种酯类致敏性芳香剂%Determination of 8 ester fragrance allergens in toys by gas chromatography-ion trap mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    吕庆; 张庆; 白桦; 李海玉; 康苏媛; 王超

    2012-01-01

    建立了气相色谱-离子阱质谱联用测定玩具中丙烯酸乙酯等8种酯类致敏性芳香剂的方法.对于布绒和贴纸玩具样品,采用丙酮超声提取20 min后过0.45 μm滤膜直接进样,对于塑料玩具样品,经相应溶剂提取,离心后,澄清溶液经Envi-carb石墨化碳固相萃取小柱净化,丙酮定客,过0.45μm滤膜后通过30 m HP-5 MS色谱柱分离,质谱进行检测,外标法定量.方法对于不同物质的定量限(LOQ)在0.05~8.0 mg/kg之间,线性范围为0.005~50 mg/L,在3个添加水平的平均回收率在80.2%~105.9%之间,RSD在0.7%~8.9%之间.该方法可用于玩具中丙烯酸乙酯等8种酯类致敏性芳香剂的检测.%A gas chromatography-ion trap mass spectrometric ( GC-IT-MS/MS) method was developed for the determination of 8 ester fragrance allergens in toys. The experimental conditions, such as sample pretreatment conditions, and the analytical conditions of GC-IT-MS/MS, were optimized. Paster toy and plush toy samples were extracted by acetone, determined by GC-IT-MS/MS. Plastic toy samples were extracted by corresponding solvents. After being centrifuged the clarified solution was concentrated through Envi-carb SPE column, and the concentration was determined by GC-IT-MS/MS and quantified by external standard method. The linear ranges were 0. 005 - 50 mg/L and the limits of quantification were 0. 05 mg/kg-8. 0 mg/kg. Results of tests for recovery and precision at 3 concentration levels were found in the ranges of 80. 2% ~ 105. 9% and ( RSDs)0. 7% ~ 8. 9% , respectively. The method is accurate and sensitive, which can be applied to the analysis of 8 ester fragrance allergens in toys.

  8. Simultaneous Proteomic Discovery and Targeted Monitoring using Liquid Chromatography, Ion Mobility Spectrometry, and Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Burnum-Johnson, Kristin E.; Nie, Song; Casey, Cameron P.; Monroe, Matthew E.; Orton, Daniel J.; Ibrahim, Yehia M.; Gritsenko, Marina A.; Clauss, Therese R. W.; Shukla, Anil K.; Moore, Ronald J.; Purvine, Samuel O.; Shi, Tujin; Qian, Weijun; Liu, Tao; Baker, Erin S.; Smith, Richard D.

    2016-09-25

    Current proteomics approaches are comprised of both broad discovery measurements as well as more quantitative targeted measurements. These two different measurement types are used to initially identify potentially important proteins (e.g., candidate biomarkers) and then enable improved quantification for a limited number of selected proteins. However, both approaches suffer from limitations, particularly the lower sensitivity, accuracy, and quantitation precision for discovery approaches compared to targeted approaches, and the limited proteome coverage provided by targeted approaches. Herein, we describe a new proteomics approach that allows both discovery and targeted monitoring (DTM) in a single analysis using liquid chromatography, ion mobility spectrometry and mass spectrometry (LC-IMS-MS). In DTM, heavy labeled peptides for target ions are spiked into tryptic digests and both the labeled and unlabeled peptides are broadly detected using LC-IMS-MS instrumentation, allowing the benefits of discovery and targeted approaches. To understand the possible improvement of the DTM approach, it was compared to LC-MS broad measurements using an accurate mass and time tag database and selected reaction monitoring (SRM) targeted measurements. The DTM results yielded greater peptide/protein coverage and a significant improvement in the detection of lower abundance species compared to LC-MS discovery measurements. DTM was also observed to have similar detection limits as SRM for the targeted measurements indicating its potential for combining the discovery and targeted approaches.

  9. 液相色谱-离子阱-飞行时间串联质谱同时检测肉制品中14种杂环胺%Determination of 14 Heterocyclic Aromatic Amines in Meat Products by Liquid Chromatography - Ion Trap - Time of Flight Tandem Mass Spectrometry

    Institute of Scientific and Technical Information of China (English)

    王敏; 郭德华; 丁卓平; 姚劲挺

    2011-01-01

    建立了液相色谱-离子阱-飞行时间串联质谱(LCMS - IT - TOF)同时测定肉制品中14种杂环胺( HAAs)残留量的分析方法.样品以乙腈提取,经Phenomenex strata-X-C小柱净化,甲醇-氨水(9:1)洗脱,氮吹至干,经1 mL乙腈-水(1:9)定容离心后上机测定,基质曲线内标法定量.结果表明,14种杂环胺在5 ~ 250 μg/L质量浓度范围内线性良好,相关系数均不低于0.994 0,检出限(S/N=3)为0.59 ~ 3.27 μg/kg.14种杂环胺在加标水平为10、50、250 μg/kg时的回收率分别为69% ~ 107%、67% ~ 106%、76% ~ 113%,相对标准偏差(RSD,n=6)分别为1.5%~15.6%、1.3%~11.8%、 1.8%~9.7%.结果显示该方法线性范围宽,精密度和准确度较高,分析时间短,净化效果好,可满足肉制品中多种杂环胺残留同时检测的要求.%A rapid analytical method was developed for the determination of 14 heterocyclic aromatic amines ( HAAs) in meat products by liquid chromatography - ion trap - time of flight tandem mass spectrometry ( LCMS - IT - TOF). The samples were extracted with acetonitrile. The extract was cleaned up with Phenomenex strata-X-C, eluted with methanol - ammonia (9 : 1 ) , then evaporated with a stream of nitrogen to near dryness and redissoved with acetonitrile - water ( 1:9). The separation of HAAs was performed on a Phenomenex Kinetex 2. 6|x C,8 100A (2. 1 mm I. D. X 100 mm, 2. 6 |xm) , using 30 mmol/L ammonium formate - acetonitrile as mobile phase by gradient elution. The analytes were detected under positive-ion electrospray ionization mode. Results showed that the linear ranges of 14 HAAs were 5 -250 |Xg/L with limits of detection (S/N = 3 ) of 0. 59 - 3. 27 |xg/ kg. The mean recoveries of all the compounds at three spiked levels of 10, 50, 250 |xg/kg were in the range of 69% -107%, 67% -106% and 76% -113%, respectively, with the corresponding RSDs(n = 6) of 1.5% -15.6%, 1.3% -11.8% and 1. 8% -9.7%, respectively. The established

  10. Determination of 21 fragrance allergens in toys by gas chromatography-ion trap mass spectrometry%气相色谱-离子阱质谱联用测定玩具中21种致敏性芳香剂

    Institute of Scientific and Technical Information of China (English)

    吕庆; 张庆; 白桦; 李海玉; 康苏媛; 王超

    2012-01-01

    建立了气相色谱-离子阱质谱联用测定布绒、贴纸和塑料玩具中苯甲醇等21种致敏性芳香剂的方法.对于布绒和贴纸玩具样品,采用丙酮超声振荡提取20 min后过0.45μm滤膜,经HP-IMS色谱柱(50 m×0.2 mm×0.5μm)分离,离子阱质谱检测.对于塑料玩具样品,采取溶解-沉淀方式提取,经Envi-carb石墨化碳固相萃取小柱净化,旋蒸、氮吹浓缩,过0.45μm滤膜后进行测定,外标法定量.方法对不同物质的定量限(LOQ)为0.02~40mg/kg,线性范围为0.002~50 mg/L,低、中、高3个添加水平的平均回收率为82.2%~110.8%,相对标准偏差(RSD)为0.6%~10.5%.该方法准确、灵敏,可用于玩具中苯甲醇等21种致敏性芳香剂含量的检测.%A method of gas chromatography-ion trap mass spectrometry (GC-IT-MS) was developed for the determination of 21 fragrance allergens in sticker toys, plush toys and plastic toys. The experimental conditions, such as sample pretreatment conditions, and the analytical conditions of GC-IT-MS, were optimized. The sticker toy samples and plush toy samples were extracted with acetone by ultrasonic wave, and the extracts were separated on an Agilent HP-IMS column (50 m x0. 2 mm x0. 5 jxm), then determined by IT-MS and quantified by external standard method. The plastic toy samples were extracted by the dissolution-precipitation approach, cleaned up with an Envi-carb solid phase extraction column and concentrated by rotary evaporation and nitrogen blowing, then determined by GC-IT-MS and quantified by external standard method. The calibration curves showed good linearity in the range of 0. 002 - 50 mg/L with the correlation coefficients greater than 0. 996 8. The limits of quantification (LOQ, S/N > 10) were 0. 02 -40 mg/kg. The average recoveries of the target compounds spiked in the sample at three concentration levels were in the range of 82. 2% - 110. 8% with the relative standard deviations (RSDs) of 0. 6% -10. 5%. These

  11. Characterization of impurities in the bulk drug lisinopril by liquid chromatography/ion trap spectrometry

    Institute of Scientific and Technical Information of China (English)

    Pei-xi ZHU; Dan-hun WANG; Cui-rong SUN; Zhi-quan SHEN

    2008-01-01

    Two trace impurities in the bulk drug lisinopril were detected by means of high-performance liquid chromatography coupled with mass spectrometry (HPLC/MS) with a simple and sensitive method suitable for HPLC/MSn analysis.The frag-mentation behavior of lisinopril and the impurities was investigated,and two unknown impurities were elucidated as 2-(6-amino-1-(1-earboxyethylamino)-1-oxohexan-2-ylamino)-4-phenylbutanoic acid and 6-amino-2-(1-carboxy-3-phenylpro-pylamino)-hexanoic acid on the basis of the multi-stage mass spectrometry and exact mass evidence.The proposed structures of the two unknown impurities were further confirmed by nuclear magnetic resonance (NMR) experiments after preparative isola-tion.

  12. 高效液相色谱-离子阱飞行时间质谱对保健食品中激素类成分的快速筛查和确证%Rapid screening and confirmation of hormones in health foods by high performance liquid chromatography-ion trap-time of flight tandem mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    王美玲; 颜鸿飞; 傅善良; 张帆; 姚劲挺; 戴华; 李拥军

    2012-01-01

    A method was developed for the screening, confirmation and quantification of 21 hormones including progesterones, etrogens, glucocorticoids and resorcylic acid lactones in health foods by high performance liquid chromatography-ion trap-time of flight tandem mass spectrometry (HPLC-IT-TOF-MS). The analytes in the sample were extracted with acetonitrile containing 1. 0% (v/v) acetic acid and the extract was purified with the mixed QuEChERS sor-bents. In the chromatographic analysis, the 21 target compounds were separated on a C18 column with the gradient elution using the mobile phases of acetonitrile and water containing 0. 1% acetic acid. The mass analyzer was performed in positive and negative full scan modes in one injection at the same time. The results showed that the linear ranges of the 21 hormones were 5. 0 -250 μg/L with the correlation coefficients above 0. 993 and the limits of quantification (LOQ, S/N≥ 10) were 2. 0 -5. 0 μg/kg and 1. 0 -2. 5 μg/L for capsule and oral solution, respectively. The method validation was carried out at three spiked levels, and the recoveries were 60. 2% - 116.0% with the relative standard deviations ( RSDs) of 7.0% - 18.3%. The screening of analytes was performed by precision mass matching and library searching. The secondary fragment ion spectra were employed to the confirmation. This method is simple, fast, reliable, and can be applied to the simultaneous screening and determination of hormones in health foods.%采用高效液相色谱-离子阱飞行时间串联质谱( HPLC-IT-TOF-MS)对保健食品中雌激素、雄激素、糖皮质激素和二羟基苯甲酸内酯类药物等21种激素成分进行快速筛查、定性识别和准确定量.样品经含1.0%乙酸的乙腈溶液超声提取,提取液经QuEChERS吸附剂净化,以C18色谱柱(150 mm ×2.0 mm,3.0μm)分离,乙腈和0.1%乙酸水溶液为流动相梯度洗脱,正、负离子模式同时扫描.结果表明,21种化合物在5.0~ 250 μg/L范围内

  13. 高效液相色谱-离子阱质谱法快速筛查改善睡眠类保健食品中非法添加的24种镇静催眠药%Fast screening of 24 sedative hypnotics illegally added in improving sleep health foods by high performance liquid chromatography-ion trap mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    芦丽; 宫旭; 谭力

    2015-01-01

    A fast screening method was established for the simultaneous determination of 24 sedative hypnotics illegally added in improving sleep health foods by high performance liquid chromatography-ion trap mass spectrometry( HPLC-IT MS). The method was based on the son-ication assisted extraction of the improving sleep health food samples using methanol. The ex-tract was then filtrated with 0. 45 μm filter membrane and the filtrate was separated on a Phe-nomenex Luna C18 column with isocratic elution at a flow rate of 0. 3 mL/min. A binary mobile phase was 0. 05%(v/v)formic acid(solvent A)-methanol/acetonitrile(15:25,v/v,solvent B). The electrospray ionization( ESI)source in positive ion mode or negative ion mode was used to scan MS1—MS3 spectra for the 24 sedative hypnotics. The MS2 and MS3 spectra were used for qualitative analysis of samples. The calibration graphs were linear in their concentra-tion ranges with the correlation coefficients( r2 ) more than 0. 999. The limits of detection ( LODs)were 4. 0—446. 6 μg/L. The recoveries for all the drugs in the improving sleep health foods were 88. 6%—110. 3% with the relative standard deviations no more than 9. 8% at three spiked levels. Twenty-seven batches of the improving sleep health foods were tested. Melatonin was found in eighteen batches. The method is fast,specific,sensitive,easy and suitable for fast screening of 24 sedative hypnotics illegally added in improving sleep health foods.%建立了高效液相色谱-离子阱质谱(HPLC-IT MS)同时测定改善睡眠类保健食品中非法添加的24种镇静催眠药的快速筛查方法。样品经甲醇超声提取20 min,经0.45μm 滤膜过滤后进行 HPLC-IT MS 分析检测。采用Phenomenex Luna C18色谱柱分离,流动相 A为0.05%( v/v)甲酸水溶液,流动相 B为甲醇-乙腈(15:25,v/v)溶液,等度洗脱;采用电喷雾离子( ESI)源及正、负离子切换模式,扫描MS1~MS3三级质谱,利用24

  14. Feasibility of ultra-performance liquid chromatography-ion mobility-time-of-flight mass spectrometry in analyzing oxysterols.

    Science.gov (United States)

    Kylli, Petri; Hankemeier, Thomas; Kostiainen, Risto

    2017-03-03

    Oxysterols are oxygenated cholesterols that are important in many cell functions and they may also be indicative of certain diseases. The purpose of this work was to study the feasibility of ultra-performance liquid chromatography-ion mobility-time-of-flight mass spectrometry (UPLC-IM-TOFMS) using traveling wave cell in analyzing oxysterols and especially their isomers in biological samples. Oxysterols were analyzed as their p-toluenesulfonyl isocyanate derivatives, which improved the separation of isomeric oxysterols by ion mobility and ionization efficiency in the electrospray ionization step. The UPLC-IM-TOFMS method was shown to be fast and to provide good quantitative performance. The feasibility of the method was demonstrated in the analyses of oxysterols in fibroblast cell samples.

  15. Single-run determination of polybrominated diphenyl ethers (PBDEs) di- to deca-brominated in fish meal, fish oil and fish feed by isotope dilution: Application of automated sample purification and gas chromatography/ion trap tandem mass spectrometry (GC/ITMS)

    Energy Technology Data Exchange (ETDEWEB)

    Blanco, Sonia Lucia, E-mail: lucia@anfaco.es [Centro Tecnico Nacional de Conservacion de Productos de la Pesca (ANFACO-CECOPESCA), Carretera Colexio Universitario No. 16, 36310, Vigo, Pontevedra (Spain); Vieites, Juan M. [Centro Tecnico Nacional de Conservacion de Productos de la Pesca (ANFACO-CECOPESCA), Carretera Colexio Universitario No. 16, 36310, Vigo, Pontevedra (Spain)

    2010-07-05

    The present paper describes the application of automated cleanup and fractionation procedures of the Power Prep system (Fluid Management Systems) for the determination of polybrominated diphenyl ethers (PBDEs) in feeding stuffs and fish meal and oil. Gas chromatography (GC) separation followed by ion trap tandem mass spectrometry detection in EI mode (ITMS) allowed the analysis of di- to deca-BDEs in the samples matrices used in fish aquaculture. The method developed enabled the determination of 26 native PBDE congeners and 11 {sup 13}C{sub 12}-labelled congeners, including deca-BDE 209, in a single-run analysis, using isotope dilution. The automated cleanup, consisting of a succession of multilayer silica and basic alumina columns previously applied by Wyrzykowska et al. (2009) in combustion flue gas, was succesfully applied in our complex matrices. The method allowed an increase in productivity, i.e. lower time was required to process samples, and simultaneous purification of several samples was achieved at a time, reducing analyst dedication and human error input. Average recoveries of 43-96% were obtained. GC/ITMS can overcome the complexity originating from the sample matrix, eliminating matrix effects by tandem MS, to enable the detection of congeners penta- to nona-BDEs where interferent masses were present. The provisional detection limits, estimated in the samples, were 5-30 pg for di-, tri-, tetra-, and penta-BDEs, 20-65 pg for hexa-, hepta-, octa- and nona-BDEs, and 105 pg for deca-BDE. Reduction of deca-BDE 209 blank values is of concern to ongoing research. Good accuracy was obtained by application of the whole procedure, representing an efficient, low-cost and fast alternative for routine analyses.

  16. Uncovering biologically significant lipid isomers with liquid chromatography, ion mobility spectrometry and mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Kyle, Jennifer E.; Zhang, Xing; Weitz, Karl K.; Monroe, Matthew E.; Ibrahim, Yehia M.; Moore, Ronald J.; Cha, Jeeyeon; Sun, Xiaofei; Lovelace, Erica S.; Wagoner, Jessica; Polyak, Steve; Metz, Thomas O.; Dey, Sudhansu K.; Smith, Richard D.; Burnum-Johnson, Kristin E.; Baker, Erin Shammel

    2016-01-01

    Understanding how biological molecules are generated, metabolized and eliminated in living systems is important for interpreting processes such as immune response and disease pathology. While genomic and proteomic studies have provided vast amounts of information over the last several decades, interest in lipidomics has also grown due to improved analytical technologies revealing altered lipid metabolism in type 2 diabetes, cancer, and lipid storage disease. Liquid chromatography and mass spectrometry (LC-MS) measurements are currently the dominant approach for characterizing the lipidome by providing detailed information on the spatial and temporal composition of lipids. However, interpreting lipids’ biological roles is challenging due to the existence of numerous structural and stereoisomers (i.e. distinct acyl chain and double-bond positions), which are unresolvable using present LC-MS approaches. Here we show that combining structurally-based ion mobility spectrometry (IMS) with LC-MS measurements distinguishes lipid isomers and allows insight into biological and disease processes.

  17. Study on Profiling Mitochondria Proteome of Human Fetal Liver by Multi-dimensional Liquid Chromatography and Liquid Chromatography-Ion Trap Mass Spectrometry%多维液相色谱及液相色谱-离子阱质谱法研究人胎肝线粒体蛋白质组

    Institute of Scientific and Technical Information of China (English)

    张养军; 石蓉; 孟庆芳; 王京兰; 蔡耘; 朱云平; 贺福初; 钱小红

    2004-01-01

    In proteomics study, because there were biases of two-dimensional gel electrophoresis in molecular weights, pH and hydrophobicity, multi-dimensional protein identification technology (MuD-PIT)was proposed. Due to the core part of the technique being digestion of total proteins in the first step, some drawbacks appeared, such as complicating the separation of samples, dominating the influence of proteins with high abundance on the identification of proteins with low abundance and losing some information of proteins,for example, post-translational modification et al. , these resulted in the limitation of applications for the method. Taking into account of those factors mentioned above, when studying the mitochondria proteome of human fetal liver with great significance in life process, Proteome Lab PF2D system (Beckman Coulter, USA) was employed. The fractions of extract from fetal liver tissues by saccharose- density gradient centrifugation were prepared on a high velocity centrifuge. The desalting and solvent exchanging of the fractions with Start buffer (pH8. 5, Beckman Coulter, USA) were carried out on a PD-10(Sephadex G-25, 5 000Da) desalting column (amersham pharmacia biotech, Wikstroms,Sweden) according to the procedures described in its product instruction. Then the treated fractions were separated with chromatofocusing and reversed-phase liquid chromatography in tandem, respectively. After concentration and in-solution digestion of protein fractions,the peptide mixture was lyophilized, then resolved with 5% aqueous acytonitrile plus 0.1% formic acid, and finally analyzed with microLC-ESI-ion trap mass spectrometry(Thermo Finnigan, San Jose, CA, USA) and CapLC-ESI-QTOF mass spectrometry (Waters, USA). Mass spectrometric data was searched against IPI protein database with Thermo SEQUEST (Thermo Finnigan, San Jose, CA, USA) and Mascot. A primary database of mitochondrial proteome of human fetal liver was constructed, which could play central role in the large

  18. Determination of 14 heterocyclic aromatic amines in wine by liquid chromatography-ion trap-time of flight tandem mass spectrometry%液相色谱-离子阱-飞行时间串联质谱同时检测葡萄酒中14种杂环胺

    Institute of Scientific and Technical Information of China (English)

    王敏; 郭德华; 丁卓平; 姚劲挺; 李锋格; 苏敏

    2012-01-01

    建立了液相色谱-离子阱-飞行时间串联质谱法(LC-IT-TOF MS)同时测定葡萄酒中14种杂环胺(HAAs)残留量的分析方法.样品于乙酸乙酯碱性条件下提取,内标法定量,Phenomenex Kinetex C18 100A色谱柱(100 mm×2.1 mm,2.6μm)分离,以乙腈和30 mmol/L甲酸铵为流动相进行梯度洗脱.实验结果表明,2-氨基-3,7,8-三甲基咪唑[4,5-f]喹喔啉在1~500 μg/L、2-氨基-3,8-二甲基咪唑[4,5-f]喹喔啉在10 ~ 500 μg/L、其他12种杂环胺在5 ~ 500μg/L质量浓度范围内线性良好,相关系数均不小于0.994 5,检出限(以信噪比为3计)0.33~1.77μg/L.14种杂环胺在加标水平为10、50、100 μg/L时的回收率分别为71.6%~96.4%、72.9% ~ 101.9%、74.5% ~103.3%,相对标准偏差(RSD,n=6)分别为2.9%~7.9%、1.7%~5.3%、1.8%~4.8%.结果显示该方法线性范围宽,精密度和准确度较高,分析时间短,净化效果好,可满足葡萄酒中多种杂环胺残留同时检测的要求.%A rapid qualitative and quantitative analytical method was developed for the simultaneous determination of 14 heterocyclic aromatic amines {HAAs) in wine by liquid chromatogra-phy-ion trap-time of flight tandem mass spectrometry (LC-1T-TOF MS). HAAs were extracted from the samples by ethyl acetate under alkaline condition. The quantitation was carried out using internal standard method. The separation of HAAs was carried out based on Phenomenex Kinetex C18 100A column (100 mm x2. 1 mm, 2. 6μm), with a gradient elution of acetonitrile and 30 mmol/L ammonium formate at a flow rate of 0. 4 mL/min. The analytes were detected under positive-ion electrospray ionization mode. The results showed that the linear ranges of the 14 HAAs were 1 - 500μg/L with limits of detection (signal/noise = 3) of 0. 33 - 1. 77μg/L. The average recoveries of all the compounds spiked in wine samples at three levels of 10, 50, 100 (j.g/L were in the ranges of 71. 6% -96.4%, 72.9% -101.9%, 74

  19. On-Line Derivatization Gas Chromatography Ion Trap Mass Spectrometry for Determination of Endocrine Disruptors in Surface Water

    Energy Technology Data Exchange (ETDEWEB)

    Tzing, Shin-Hwa; Chang, Jia-Yaw; Ling, Yong-Chien

    2004-03-31

    A method has been developed for the determination of endocrine disruptors (EDs) (containing hydroxyl groups) in surface water from different sources. The surface water samples from different sites including school and local dormitory sewage effluents, lake water and river water were collected and analyzed. In this method, the pretreated sample is directly analyzed by GC-MS using on-line derivatization, where tetramethylammonium hydroxide (TMA-OH) was used as the derivatizing agent. Use of large-volume direct sample introduction (DSI) and co-injection of the sample and TMAOH avoids external contaminations as observed in conventional derivatization protocols. Additionally, the use of chemical ionization (CI) and CI-MS/MS could enable detection of EDs at lower concentrations and reduce the matrices' interference thereby enhancing detection sensitivity of EDs for quantification. In this work, the use of dichloromethane as CI reagent for EDs is reported for the first time and could detect EDs to concentrations as low as 0.5 pg/mL. The recovery ranged from 74 to 112 % and the relative standard derivations for replicate analyses ranged from 5 to 17 %. We hope that this method will be applicable for routine analysis of EDs with hydroxyl functional groups.

  20. Non-targeted and targeted analysis of wild toxic and edible mushrooms using gas chromatography-ion trap mass spectrometry.

    Science.gov (United States)

    Carvalho, Luís Miguel; Carvalho, Félix; de Lourdes Bastos, Maria; Baptista, Paula; Moreira, Nathalie; Monforte, Ana Rita; da Silva Ferreira, António César; de Pinho, Paula Guedes

    2014-01-01

    Mushrooms are known all over the world both due to the remarkable gastronomic value of some species and for severe intoxications mediated by other species that are frequently difficult to distinguish from the edible ones, by the common user. Therefore, it is important to develop strategies to discover molecules that can identify mushroom species. In the present work, two GC-MS methodologies were applied in the chemical characterization of 22 mushroom species (12 edible, 3 toxic and 7 potentially toxic) - a multi-target procedure to simultaneously determine amino acids (AA), fatty acids (FA) and sterols by previous derivatization procedure with MSTFA, and a Head Space-Solid Phase Microextraction method to determine volatiles. For both methods, two approaches to data analysis were used: (I) targeted analysis, to identify and quantify AA, FA sterols and volatiles; (II) untargeted analysis, including Principal Component Analysis and Partial Least Square Discriminant Analysis, in order to identify metabolites/metabolite pattern with potential species identification and/or differentiation. Multi-target experiment allowed the identification and quantification of twenty one primary metabolites (9 AA, 11 FA and 1 sterol). Furthermore, through untargeted data analysis, it was possible to identify a 5-carbon sugar alcohol structure molecule, which was tentatively identified as xylitol or adonitol, with potential to be a species-marker of the edible Suillus bovinus mushrooms. Volatile profiling studies resulted in the identification of the main volatiles in mushrooms. Untargeted analysis allowed the identification of 6 molecules that can be species- or genus-specific: one secondary metabolite specific to the edible species Lycoperdon perlatum, an ester of hexanoic acid, tentatively identified as allyl or vinyl caproate; and five other secondary metabolites, whose identification was not achieved, which were only detected in Lactarius aurantiacus specimens (edibility/toxicity unknown).

  1. Carbon cluster mass calibration at the double Penning trap mass spectrometer TRIGA-TRAP

    Energy Technology Data Exchange (ETDEWEB)

    Smorra, Christian [Physikalisches Institut, Universitaet Heidelberg (Germany); Institut fuer Kernchemie, Universitaet Mainz (Germany); Blaum, Klaus [Physikalisches Institut, Universitaet Heidelberg (Germany); Max-Planck Institut fuer Kernphysik, Heidelberg (Germany); Eberhardt, Klaus [Institut fuer Kernchemie, Universitaet Mainz (Germany); Eibach, Martin; Ketelaer, Jens; Ketter, Jochen; Knuth, Konstantin [Institut fuer Physik, Universitaet Mainz (Germany); Herfurth, Frank [GSI, Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Nagy, Szilard [Max-Planck Institut fuer Kernphysik, Heidelberg (Germany)

    2009-07-01

    TRIGA-TRAP is a facility which aims for mass measurements on neutron-rich short-lived fission products and actinides with relative mass uncertainties of 10{sup -7} and below. To this end the cyclotron frequency of a stored ion in a Penning trap is determined. In high-precision mass spectrometry the investigation of systematic errors is of utmost importance. In order to demonstrate the accuracy of the measured values, various carbon cluster ions have been used in cross reference measurements. The results are presented and the accuracy limit of TRIGA-TRAP is discussed.

  2. Miniaturized Linear Wire Ion Trap Mass Analyzer.

    Science.gov (United States)

    Wu, Qinghao; Li, Ailin; Tian, Yuan; Zare, Richard N; Austin, Daniel E

    2016-08-02

    We report a linear ion trap (LIT) in which the electric field is formed by fine wires held under tension and accurately positioned using holes drilled in two end plates made of plastic. The coordinates of the hole positions were optimized in simulation. The stability diagram and mass spectra using boundary ejection were compared between simulation and experiment and good agreement was found. The mass spectra from experiments show peak widths (fwhm) in units of mass-to-charge of around 0.38 Th using a scan rate of 3830 Th/s. The limits of detection are 137 ppbv and 401 ppbv for benzene and toluene, respectively. Different sizes of the wire ion trap can be easily fabricated by drilling holes in scaled positions. Other distinguishing features, such as high ion and photon transmission, low capacitance, high tolerance to mechanical and assembly error, and low weight, are discussed.

  3. Damping effects in Penning trap mass spectrometry

    CERN Document Server

    George, S; Kowalska, M; Dworschak, M; Neidherr, D; Blaum, K; Schweikhard, L; Ramirez, E M; Breitenfeldt, M; Kretzschmar, M; Herfurth, F; Schwarz, S; Herlert, A

    2011-01-01

    Collisions of ions with residual gas atoms in a Penning trap can have a strong influence on the trajectories of the ions, depending on the atom species and the gas pressure. We report on investigations of damping effects in time-of-flight ion-cyclotron resonance mass spectrometry with the Penning trap mass spectrometers ISOLTRAP at ISOLDE/CERN (Geneva, Switzerland) and SHIPTRAP at GSI (Darmstadt, Germany). The work focuses on the interconversion of the magnetron and cyclotron motional modes, in particular the modification of the resonance profiles for quadrupolar excitation due to the damping effect of the residual gas. Extensive experiments have been performed with standard and Ramsey excitation schemes. The results are in good agreement with predictions obtained by analytical continuation of the formulae for the undamped case.

  4. Receptor-based high-throughput screening and identification of estrogens in dietary supplements using bioaffinity liquid-chromatography ion mobility mass spectrometry

    NARCIS (Netherlands)

    Aqai, P.; Gómez Blesa, N.; Major, H.; Pedotti, P.; Varani, L.; Ferrero, V.E.V.; Haasnoot, W.; Nielen, M.W.F.

    2013-01-01

    A high-throughput bioaffinity liquid chromatography-mass spectrometry (BioMS) approach was developed and applied for the screening and identification of recombinant human estrogen receptor a (ERa) ligands in dietary supplements. For screening, a semi-automated mass spectrometric ligand binding assay

  5. Use of solid-phase microextraction for the detection of acetic acid by ion-trap gas chromatography-mass spectrometry and application to indoor levels in museums.

    Science.gov (United States)

    Godoi, Ana F L; Van Vaeck, Luc; Van Grieken, René

    2005-03-01

    A simple and efficient method using solid-phase microextraction (SPME) and gas chromatography-ion trap mass spectrometry (GC-ITMS) was developed for the analysis of acetic acid in air. The choice of the SPME fibre revealed to be critical as well as the sampling and desorption time. A dilution vessel was used for calibration. The precision of the method was found to be 4.7% relative standard deviation (RSD) and the detection limit 5.7 microg m(-3). The SPME-GC-MS technique was applied to the analysis of acetic acid in museum atmospheres.

  6. Mass measurements with a Penning trap mass spectrometer at ISOLDE

    CERN Document Server

    Bollen, G; Audi, G; Beck, D; Herfurth, F; Kluge, H J; Kohl, A; Lunney, M D; Moore, R B; De Saint-Simon, M; Schark, E; Schwarz, S; Szerypo, J

    1998-01-01

    Penning trap mass measurements on radioactive isotopes are performed with the ISOLTRAP mass spectrometer at ISOLDE/CERN. In the last years the applicability of the spectrometer has been considerably extended. The most recent measurements were carried out on isotopes of rare earth elements and on isotopes with Z=80-85. An accuracy of $\\delta$ m/m approximately=1$\\cdot$10$^{-7}$was achieved. (19 refs).

  7. Optimization of a liquid chromatography ion mobility-mass spectrometry method for untargeted metabolomics using experimental design and multivariate data analysis.

    Science.gov (United States)

    Tebani, Abdellah; Schmitz-Afonso, Isabelle; Rutledge, Douglas N; Gonzalez, Bruno J; Bekri, Soumeya; Afonso, Carlos

    2016-03-24

    High-resolution mass spectrometry coupled with pattern recognition techniques is an established tool to perform comprehensive metabolite profiling of biological datasets. This paves the way for new, powerful and innovative diagnostic approaches in the post-genomic era and molecular medicine. However, interpreting untargeted metabolomic data requires robust, reproducible and reliable analytical methods to translate results into biologically relevant and actionable knowledge. The analyses of biological samples were developed based on ultra-high performance liquid chromatography (UHPLC) coupled to ion mobility - mass spectrometry (IM-MS). A strategy for optimizing the analytical conditions for untargeted UHPLC-IM-MS methods is proposed using an experimental design approach. Optimization experiments were conducted through a screening process designed to identify the factors that have significant effects on the selected responses (total number of peaks and number of reliable peaks). For this purpose, full and fractional factorial designs were used while partial least squares regression was used for experimental design modeling and optimization of parameter values. The total number of peaks yielded the best predictive model and is used for optimization of parameters setting.

  8. Mass trapping with MosquiTRAPs does not reduce Aedes aegypti abundance

    Directory of Open Access Journals (Sweden)

    Carolin Marlen Degener

    2015-06-01

    Full Text Available The objective of this study was to evaluate the effectiveness of Aedes aegypti mass trapping using the sticky trap MosquiTRAP (MQT by performing a cluster randomised controlled trial in Manaus, state of Amazonas, Brazil. After an initial questionnaire and baseline monitoring of adult Ae. aegypti abundance with BG-Sentinel (BGS traps in six clusters, three clusters were randomly assigned to the intervention arm where each participating household received three MQTs for mass trapping during 17 months. The remaining three clusters (control arm did not receive traps. The effect of mass trapping on adult Ae. aegypti abundance was monitored fortnightly with BGS traps. During the last two months of the study, a serological survey was conducted. After the study, a second questionnaire was applied in the intervention arm. Entomological monitoring indicated that MQT mass trapping did not reduce adult Ae. aegypti abundance. The serological survey indicated that recent dengue infections were equally frequent in the intervention and the control arm. Most participants responded positively to questions concerning user satisfaction. According to the results, there is no evidence that mass trapping with MQTs can be used as a part of dengue control programs. The use of this sticky trap is only recommendable for dengue vector monitoring.

  9. Mass trapping with MosquiTRAPs does not reduce Aedes aegypti abundance.

    Science.gov (United States)

    Degener, Carolin Marlen; de Ázara, Tatiana Mingote Ferreira; Roque, Rosemary Aparecida; Rösner, Susanne; Rocha, Eliseu Soares Oliveira; Kroon, Erna Geessien; Codeço, Cláudia Torres; Nobre, Aline Araújo; Ohly, Jörg Johannes; Geier, Martin; Eiras, Álvaro Eduardo

    2015-06-01

    The objective of this study was to evaluate the effectiveness of Aedes aegypti mass trapping using the sticky trap MosquiTRAP (MQT) by performing a cluster randomised controlled trial in Manaus, state of Amazonas, Brazil. After an initial questionnaire and baseline monitoring of adult Ae. aegypti abundance with BG-Sentinel (BGS) traps in six clusters, three clusters were randomly assigned to the intervention arm where each participating household received three MQTs for mass trapping during 17 months. The remaining three clusters (control arm) did not receive traps. The effect of mass trapping on adult Ae. aegypti abundance was monitored fortnightly with BGS traps. During the last two months of the study, a serological survey was conducted. After the study, a second questionnaire was applied in the intervention arm. Entomological monitoring indicated that MQT mass trapping did not reduce adult Ae. aegypti abundance. The serological survey indicated that recent dengue infections were equally frequent in the intervention and the control arm. Most participants responded positively to questions concerning user satisfaction. According to the results, there is no evidence that mass trapping with MQTs can be used as a part of dengue control programs. The use of this sticky trap is only recommendable for dengue vector monitoring.

  10. Broad-band FT-ICR detection at the Penning trap mass spectrometer TRIGA-TRAP

    Energy Technology Data Exchange (ETDEWEB)

    Knuth, Konstantin; Eibach, Martin; Ketelaer, Jens; Ketter, Jochen; Sturm, Sven [Institut fuer Physik, Universitaet Mainz (Germany); Blaum, Klaus [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Physikalisches Institut, Universitaet Heidelberg Heidelberg (Germany); Block, Michael; Herfurth, Frank [GSI, Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Eberhardt, Klaus [Institut fuer Kernchemie, Universitaet Mainz (Germany); Nagy, Szilard [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Repp, Julia [Institut fuer Physik, Universitaet Mainz (Germany); Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Smorra, Christian [Physikalisches Institut, Universitaet Heidelberg Heidelberg (Germany); Institut fuer Kernchemie, Universitaet Mainz (Germany); Ulmer, Stefan [Institut fuer Physik, Universitaet Mainz (Germany); Physikalisches Institut, Universitaet Heidelberg Heidelberg (Germany)

    2009-07-01

    The double Penning trap mass spectrometer TRIGA-TRAP will perform high-precision mass measurements on exotic neutron-rich nuclides, which are produced via neutron-induced fission of actinide targets at the research reactor TRIGA Mainz. In order to determine which ion species are present in the ion bunch delivered to the Penning trap system, a non-destructive ion detection technique will be implemented in the cylindrical purification trap. This so called broad-band Fourier transform ion cyclotron resonance (FT-ICR) detection technique is based on the detection of image currents, induced by the ions in the trap electrodes. To this end, a new cryogenic low-noise broad-band amplifier is being designed and tested. With this system the identification of contaminations will be possible without the need to eject ions from the trap as usually done at other facilities. The setup as well as its present status are presented.

  11. Effectiveness of different trap design in mass trapping of Bothynoderes punctiventris Germar

    Directory of Open Access Journals (Sweden)

    Sivčev Ivan L.

    2006-01-01

    Full Text Available The discovery of an aggregation attractant for Bothynoderes punctiventris Germ. raised several questions for possible improvements of IPM of Bothynoderes punctiventris in sugar beet. First results on exploration of possibilities for its use for monitoring purposes as well as for mass trapping of adults of the pest are described in this paper. Trap design effectiveness was evaluated in the overwintering fields of sugar beet weevil for two years in localities in Serbia and Hungary. Among trap designs tested it was proved that baited CSALOMON® TAL trap design was optimal.

  12. Practical aspects of trapped ion mass spectrometry, 5 applications of ion trapping devices

    CERN Document Server

    March, Raymond E

    2009-01-01

    Examines ion/neutral and ion/ion reactions, ion spectroscopy, and the structural characterization of proteins and peptides using quadropole ion trap mass spectrometry, Fourier transform - ion cyclotron resonance (FT-ICR) mass spectrometry, and traveling wave ion mobility mass spectrometry.

  13. Dynamic headspace coupled to perevaporation for the analysis of anisoles in wine by gas chromatography-ion-trap tandem mass spectrometry.

    Science.gov (United States)

    Gómez-Ariza, J L; García-Barrera, T; Lorenzo, F

    2004-11-12

    Off-flavours in wines are mainly due to the presence of 2,4,6-trichloroanisole and other haloanisoles. The purpose of this study was to develop a method based on the coupling of dynamic headspace and perevaporation to GC-MS-MS to attain better analyte sensitivity and selectivity. The approach has been applied to the analysis of 2,6-dichloroanisole, 2,4,6-trichloroanisole and 2,4,6-tribromoanisole in various wines. For these compounds that cause taste and odour problems, the method was linear from the quantification limit to 3 ng for all the analytes with recoveries greater than 80% and satisfactory precision. Detection limits were as low as 2-36 ng l(-1).

  14. ANALYSIS OF AIRBORNE CARBOXYLIC ACIDS AND PHENOLS AS THEIR PENTAFLUOROBENZYL DERIVATIVES: GAS CHROMATOGRAPHY/ION TRAP MASS SPECTROMETRY WITH A NOVEL CHEMICAL IONIZATION REAGENT, PFBOH. (R826247)

    Science.gov (United States)

    The complex photochemical transformations of biogenichydrocarbons such as isoprene and of anthropogenichydrocarbons such as aromatics are an important sourceof carboxylic acids in the troposphere. Theidentificationof unknown carboxylic acids can be difficul...

  15. Differentially pumped dual linear quadrupole ion trap mass spectrometer

    Science.gov (United States)

    Owen, Benjamin C.; Kenttamaa, Hilkka I.

    2016-11-15

    The present disclosure provides a new tandem mass spectrometer and methods of using the same for analyzing charged particles. The differentially pumped dual linear quadrupole ion trap mass spectrometer of the present disclose includes a combination of two linear quadrupole (LQIT) mass spectrometers with differentially pumped vacuum chambers.

  16. Differentially pumped dual linear quadrupole ion trap mass spectrometer

    Science.gov (United States)

    Owen, Benjamin C.; Kenttamaa, Hilkka I.

    2015-10-20

    The present disclosure provides a new tandem mass spectrometer and methods of using the same for analyzing charged particles. The differentially pumped dual linear quadrupole ion trap mass spectrometer of the present disclose includes a combination of two linear quadrupole (LQIT) mass spectrometers with differentially pumped vacuum chambers.

  17. TRIGA-TRAP: A penning trap mass spectrometer at the research reactor TRIGA Mainz

    Energy Technology Data Exchange (ETDEWEB)

    Smorra, Christian [Physikalisches Institut, Universitaet Heidelberg (Germany); Institut fuer Kernchemie, Universitaet Mainz (Germany); Blaum, Klaus [Physikalisches Institut, Universitaet Heidelberg (Germany); Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Block, Michael; Herfurth, Frank [GSI, Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Eberhardt, Klaus [Institut fuer Kernchemie, Universitaet Mainz (Germany); Eibach, Martin; Ketelaer, Jens; Ketter, Jochen; Knuth, Konstantin; Repp, Julia [Institut fuer Physik, Universitaet Mainz (Germany); Nagy, Szilard [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany)

    2009-07-01

    Nuclear masses represent the binding energies and, therefore, the sum of all interactions in the nucleus. They provide an important input parameter to nuclear structure models. Presently, a tremendous interest in masses of very exotic neutron-rich nuclides exists to support theoretical models for the nucleosynthesis via the rapid neutron capture process. The research reactor TRIGA Mainz provides access to a large variety of neutron-rich nuclides produced by thermal-neutron induced fission of an actinide target. The double-Penning trap mass spectrometer TRIGA-TRAP will perform high-precision mass measurements in this region of the nuclear chart as well as on actinides from uranium to californium. It also serves as a test facility for the development of new techniques that will be implemented in future facilities like MATS at FAIR (GSI, Darmstadt). The layout of TRIGA-TRAP as well as recent mass measurements are presented.

  18. Ion trap with integrated time-of-flight mass spectrometer

    CERN Document Server

    Schneider, Christian; Yu, Peter; Hudson, Eric R

    2015-01-01

    Recently, we reported an ion trap experiment with an integrated time-of-flight mass spectrometer (TOFMS) [Phys. Rev. Appl. 2, 034013 (2014)] focussing on the improvement of mass resolution and detection limit due to sample preparation at millikelvin temperatures. The system utilizes a radio-frequency (RF) ion trap with asymmetric drive for storing and manipulating laser-cooled ions and features radial extraction into a compact $275$ mm long TOF drift tube. The mass resolution exceeds $m / \\Delta m = 500$, which provides isotopic resolution over the whole mass range of interest in current experiments and constitutes an improvement of almost an order of magnitude over other implementations. In this manuscript, we discuss the experimental implementation in detail, which is comprised of newly developed drive electronics for generating the required voltages to operate RF trap and TOFMS, as well as control electronics for regulating RF outputs and synchronizing the TOFMS extraction.

  19. Recent results from the Penning trap mass spectrometer ISOLTRAP

    CERN Document Server

    Blaum, Klaus; Beck, D; Bollen, Georg; Delahaye, P; Guenaut, C; Herfurth, F; Kellerbauer, Alban G; Kluge, H J; Lunney, M D; Rodríguez, D; Schwarz, S; Schweikhard, L; Weber, C; Yazidjian, C

    2004-01-01

    In the last few years a number of new scientific highlights have been obtained by ISOLTRAP, the tandem Penning trap mass spectrometer for on-line mass measurements of short-lived radionuclides. The precise determination of nuclear binding energies far from stability includes nuclei that are produced at rates of 100 ions/s and with half-lives below 100 ms. The mass resolving power reaches 10$^{7}$ and the uncertainty of the resulting mass values has been pushed down to $1 \\times 10^{-8}$. In this article recent ISOLTRAP mass measurements are summarized and the current status of ISOLTRAP is presented.

  20. Recent developments in Penning-trap mass spectrometry

    Science.gov (United States)

    Block, M.

    2016-06-01

    Penning-trap mass spectrometry provides atomic masses with the highest precision. At accelerator-based on-line facilities it is applied to investigate exotic radionuclides in the context of tests of fundamental symmetries, nuclear structure studies, and nuclear astrophysics research. Recent progress in slowing down radioactive ion-beams in buffer-gas cells in combination with advanced ion-manipulation techniques has paved the way to reach nuclides ever-more far from stability. In this endeavor many efforts are underway to increase the sensitivity, the efficiency, and the precision of Penning-trap mass spectrometry. In this article some recent experimental developments are addressed with the focus on the phase-imaging ion-cyclotron-resonance technique and the Fourier transform ion-cyclotron-resonance technique.

  1. Software development for a fluid portable ion trap mass spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Hart, K.J.; Buchanan, M.V.; Wise, M.B. [Oak Ridge National Lab., TN (United States)

    1994-12-31

    Most mass spectrometer data systems are developed and optimized for the benchtop GC/MS market and thus do not adequately address the requirements for direct sampling methods. Field analysis also places greater demands on real-time data processing including automated interpretation and quantification for target analytes. The current field portable ion trap mass spectrometers developed at ORNL are based on the Finnigan Magnum ion trap mass spectrometer which provides a procedure language for user programs. A series of these procedures has been developed to support direct sampling ion trap mass spectrometry studies and is part of an overall software development strategy to address the needs of these direct sampling instruments for rapid field analysis and process monitoring. The general approach has been to create task oriented menus that lead a user through a complete analysis. Thus, the user is focused on completing tasks rather than learning and using all of the software components to complete the task. Additionally, user input has been minimized to save keyboard input and data logging time.

  2. Mass measurements on radioactive isotopes with a Penning trap mass spectrometer

    CERN Document Server

    Bollen, G; Audi, G; Beck, D; Herfurth, F; Kluge, H J; Kohl, A; Lunney, M D; Moore, R B; De Saint-Simon, M; Schark, E; Schwarz, S; Szerypo, R B

    1999-01-01

    Penning trap mass measurements on short-lived isotopes are performed with the ISOLTRAP mass spectrometer at the radioactive beam facility ISOLDE/CERN. In the last years the applicability of the spectrometer has been considerably extended by the installation of an RFQ trap ion beam buncher and a new cooler Penning trap, which is operated as an isobar separator. These improvements allowed for the first time measurements on isotopes of rare earth elements and on isotopes with Z=80-85. In all cases an accuracy of $\\delta$m/m approximately =1$\\cdot$10$^{-7}$was achieved. (20 refs).

  3. Mass Measurements with the Canadian Penning Trap at CARIBU

    Science.gov (United States)

    Orford, Rodney

    2017-01-01

    Roughly half of the elements heavier than iron are thought to be produced through the astrophysical r process of nucleosynthesis. Despite its large influence in explaining the observed abundance of heavy elements, much of the r process is still poorly understood. A more thorough library of nuclear data of neutron-rich nuclei is needed to improve the accuracy and progression of r-process calculations. In particular, accurate mass measurements are in demand due to the strong coupling between mass and other nuclear properties such as β-decay and neutron-capture rates. For nearly three decades, direct mass measurements conducted by Penning trap mass spectrometers have proven to be an accurate method of determining masses to a precision suitable for r-process calculations (Δm / m Science User Facility.

  4. Laser desorption lamp ionization source for ion trap mass spectrometry.

    Science.gov (United States)

    Wu, Qinghao; Zare, Richard N

    2015-01-01

    A two-step laser desorption lamp ionization source coupled to an ion trap mass spectrometer (LDLI-ITMS) has been constructed and characterized. The pulsed infrared (IR) output of an Nd:YAG laser (1064 nm) is directed to a target inside a chamber evacuated to ~15 Pa causing desorption of molecules from the target's surface. The desorbed molecules are ionized by a vacuum ultraviolet (VUV) lamp (filled with xenon, major wavelength at 148 nm). The resulting ions are stored and detected in a three-dimensional quadrupole ion trap modified from a Finnigan Mat LCQ mass spectrometer operated at a pressure of ≥ 0.004 Pa. The limit of detection for desorbed coronene molecules is 1.5 pmol, which is about two orders of magnitude more sensitive than laser desorption laser ionization mass spectrometry using a fluorine excimer laser (157 nm) as the ionization source. The mass spectrum of four standard aromatic compounds (pyrene, coronene, rubrene and 1,4,8,11,15,18,22,25-octabutoxy-29H,31H-phthalocyanine (OPC)) shows that parent ions dominate. By increasing the infrared laser power, this instrument is capable of detecting inorganic compounds.

  5. A novel ion cooling trap for multi-reflection time-of-flight mass spectrograph

    CERN Document Server

    Ito, Y; Wada, M; Naimi, S; Smorra, C; Sonoda, T; Mita, H; Takamine, A; Okada, K; Ozawa, A; Wollnik, H

    2013-01-01

    A radiofrequency quadrupole ion trap system for use with a multi-reflection time-of-flight mass spectrograph (MRTOF) for short-lived nuclei has been developed. The trap system consists of two different parts, an asymmetric taper trap and a flat trap. The ions are cooled to a sufficient small bunch for precise mass measurement with MRTOF in only 2 ms cooling time in the flat trap, then orthogonally ejected to the MRTOF for mass analysis. A trapping efficiency of ~27% for 23Na+ and ~5.1% for 7Li+ has been achieved.

  6. High-precision masses of neutron-deficient rubidium isotopes using a Penning trap mass spectrometer

    CERN Document Server

    Kellerbauer, A G; Beck, D; Blaum, K; Bollen, G; Guénaut, C; Herfurth, F; Herlert, A; Kluge, H J; Lunney, D; Schwarz, S; Schweikhard, L; Weber, C; Yazidjian, C

    2007-01-01

    The atomic masses of the neutron-deficient radioactive rubidium isotopes $^{74-77,79,80,83}$Rb have been measured with the Penning trap mass spectrometer ISOLTRAP. Using the time-of-flight cyclotron resonance technique, relative mass uncertainties ranging from $1.6 \\times 10^{-8}$ to $5.6 \\times 10^{-8}$ were achieved. In all cases, the mass precision was significantly improved as compared with the prior Atomic-Mass Evaluation; no significant deviations from the literature values were observed. The exotic nuclide $^{74}$Rb with a half-life of only 65 ms, is the shortest-lived nuclide on which a high-precision mass measurement in a Penning trap has been carried out. The significance of these measurements for a check of the conserved-vector-current hypothesis of the weak interaction and the unitarity of the Cabibbo-Kobayashi-Maskawa matrix is discussed.

  7. A hand-portable digital linear ion trap mass spectrometer.

    Science.gov (United States)

    Xue, Bing; Sun, Lulu; Huang, Zhengxu; Gao, Wei; Fan, Rongrong; Cheng, Ping; Ding, Li; Ma, Li; Zhou, Zhen

    2016-10-07

    A hand-portable digital linear ion trap mass spectrometer (DLIT-MS) has been developed for VOC analysis. It has a weight of 18 kg with dimensions of 49 cm × 39 cm × 16 cm, and consumes an average power of ca. 60 W. As a result of the introduction of a digital waveform, the DLIT-MS can be driven at a lower voltage (±100 V) to cover a mass range of 30-300 Th with a unit resolution. Compact electronics has been designed to control the DLIT-MS and record mass spectra. The mass drift was reduced after the improvement in electronics to stabilize the digital waveform voltage during the mass scan. Tandem mass spectrometry (MS) has been achieved by using digital asymmetric waveform isolation (DAWI), forward and reverse scan, and collision induced dissociation (CID). The isolation and CID efficiency for methyl salicylate were 83.9% and 81.3%, respectively. A novel buffer gas inlet system was designed to enhance the sensitivity and allow easy and safe use of the instrument. Limits of detection below 1 ppbv were obtained for several mixed gaseous samples.

  8. High-accuracy mass determination of unstable nuclei with a Penning trap mass spectrometer

    CERN Multimedia

    2002-01-01

    The mass of a nucleus is its most fundamental property. A systematic study of nuclear masses as a function of neutron and proton number allows the observation of collective and single-particle effects in nuclear structure. Accurate mass data are the most basic test of nuclear models and are essential for their improvement. This is especially important for the astrophysical study of nuclear synthesis. In order to achieve the required high accuracy, the mass of ions captured in a Penning trap is determined via their cyclotron frequency $ \

  9. Efficacy of pheromone trapping of the sweetpotato weevil (Coleoptera: Brentidae): based on dose, septum age, attractive radius, and mass trapping.

    Science.gov (United States)

    Reddy, Gadi V P; Wu, Shaohui; Mendi, Robert C; Miller, Ross H

    2014-06-01

    Pheromone dose, effective trapping distance, and longevity of the rubber septa loaded with sex pheromone of Cylas formicarius (F.) (Coleoptera: Brentidae) were evaluated for their impact on the efficacy of mass trapping of the insect in sweet potato fields in Guam in 2012-2013. The number of adults caught at different distances (10-100 m) was significantly different. Catches declined with increasing release distance from the trap in both downwind and upwind directions. While the maximum radius of attraction of pheromone-baited trap for C. formicarius in the field was 80 m, the effective distance for recapturing marked adults in the pheromone-baited Unitraps was 60 m. Pheromone lures were able to capture adults of C. formicarius after being stored in the laboratory for up to 98 d. The number of catches per trap per week was highest when lures were 0-14- and 15-28-d-old, and longer storage of septa led to a progressive reduction of catches. Pheromone traps baited with 100-μg lures captured significantly more adults compared with those loaded with 10-μg lures. In addition, effectiveness of pheromone trapping on damage to sweet potato was tested at two locations. Number of trapped adults, damage level at different times after trap installation, and yield production were evaluated. The number of C. formicarius adults collected in traps at both locations fluctuated dramatically among sampling dates and peaked on 13 September 2013, after which time the number of captures noticeably declined. This decrease was correlated to the increasing age and depletion of the pheromone lures. Pheromone traps significantly reduced feeding damage caused by weevils (pheromone-baited traps are effective in reducing damage due to C. formicarius.

  10. High-Precision Mass Measurements of Exotic Nuclei with the Triple-Trap Mass Spectrometer Isoltrap

    CERN Multimedia

    Blaum, K; Zuber, K T; Stanja, J

    2002-01-01

    The masses of close to 200 short-lived nuclides have already been measured with the mass spectrometer ISOLTRAP with a relative precision between 1$\\times$10$^{-7}$ and 1$\\times$10^{-8}$. The installatin of a radio-frequency quadrupole trap increased the overall efficiency by two orders of magnitude which is at present about 1%. In a recent upgrade, we installed a carbon cluster laser ion source, which will allow us to use carbon clusters as mass references for absolute mass measurements. Due to these improvements and the high reliability of ISOLTRAP we are now able to perform accurate high-precision mass measurements all over the nuclear chart. We propose therefore mass measurements on light, medium and heavy nuclides on both sides of the valley of stability in the coming four years. ISOLTRAP is presently the only instrument capable of the high precision required for many of the proposed studies.

  11. A novel ion cooling trap for multi-reflection time-of-flight mass spectrograph

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Y., E-mail: yito@riken.jp [SLOWRI Team, Nishina Accelerator-Based Research Center, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 (Japan); Schury, P. [SLOWRI Team, Nishina Accelerator-Based Research Center, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 (Japan); New Mexico State University, Department Chemistry and Biochemistry, Las Cruces, NM 88003 (United States); Wada, M.; Naimi, S. [SLOWRI Team, Nishina Accelerator-Based Research Center, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Smorra, C. [SLOWRI Team, Nishina Accelerator-Based Research Center, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); Sonoda, T. [SLOWRI Team, Nishina Accelerator-Based Research Center, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Mita, H. [SLOWRI Team, Nishina Accelerator-Based Research Center, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 (Japan); Takamine, A. [SLOWRI Team, Nishina Accelerator-Based Research Center, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Aoyama Gakuin University, 4-4-25 Shibuya, Shibuya-ku, Tokyo 150-8366 (Japan); Okada, K. [SLOWRI Team, Nishina Accelerator-Based Research Center, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Sophia University, 7-1 Kioi-cho, Chiyoda-ku, Tokyo 102-8554 (Japan); Ozawa, A. [University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 (Japan); Wollnik, H. [SLOWRI Team, Nishina Accelerator-Based Research Center, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); New Mexico State University, Department Chemistry and Biochemistry, Las Cruces, NM 88003 (United States)

    2013-12-15

    Highlights: • Fast cooling time: 2 ms. • High efficiency: ≈27% for {sup 23}Na{sup +} and ≈5.1% for {sup 7}Li{sup +}. • 100% Duty cycle with double trap system. -- Abstract: A radiofrequency quadrupole ion trap system for use with a multi-reflection time-of-flight mass spectrograph (MRTOF) for short-lived nuclei has been developed. The trap system consists of two different parts, an asymmetric taper trap and a flat trap. The ions are cooled to a sufficient small bunch for precise mass measurement with MRTOF in only 2 ms cooling time in the flat trap, then orthogonally ejected to the MRTOF for mass analysis. A trapping efficiency of ≈27% for {sup 23}Na{sup +} and ≈5.1% for {sup 7}Li{sup +} has been achieved.

  12. Direct trace analysis of metals and alloys in a quadrupole ion-trap mass spectrometer

    CERN Document Server

    Song, K S; Yang, M; Cha, H K; Lee, J M; Lee, G H

    1999-01-01

    An ion-trap mass spectrometer adopting a quadrupole ion-trap and laser ablation/ionization method was constructed. The developed system was tested for composition analysis of some metals (Cu, stainless), and alloys (hastalloy C, mumetal) by mass spectrometry. Samples were analyzed by using laser ablation from a sample probe tip followed by a mass analysis with the quadrupole ion-trap. The quadrupole ion-trap was modified to enable laser ablation by a XeCl excimer laser pulse that passed radially through the ring electrode. A mass scan of the produced ions was performed in the mass selective instability mode wherein trapped ions were successively detected by increasing the rf voltage through the ring electrode. Factors affecting the mass resolution, such as pressure of buffer gas and ablation laser power, are discussed.

  13. Practical aspects of trapped ion mass spectrometry, 4 theory and instrumentation

    CERN Document Server

    March, Raymond E

    2010-01-01

    The expansion of the use of ion trapping in different areas of mass spectrometry and different areas of application indicates the value of a single source of information drawing together diverse inputs. This book provides an account of the theory and instrumentation of mass spectrometric applications and an introduction to ion trapping devices.

  14. PENTATRAP. A novel Penning-trap system for high-precision mass measurements

    Energy Technology Data Exchange (ETDEWEB)

    Doerr, Andreas

    2015-01-21

    The novel Penning-trap mass spectrometer PENTATRAP aims at mass-ratio determinations of medium-heavy to heavy ions with relative uncertainties below 10{sup -11}. From the mass ratios of certain ion species, the corresponding mass differences will be determined with sub-eV/c{sup 2} uncertainties. These mass differences are relevant for neutrino-mass experiments, a test of special relativity and tests of bound-state QED. Means to obtain the required precision are very stable trapping fields, the use of highly-charged ions produced by EBITs, a non-destructive cyclotron-frequency determination scheme employing detectors with single-ion sensitivity and a five-trap tower, that allows for measurement schemes being insensitive to magnetic field drifts. Within this thesis, part of the detection electronics was set up and tested under experimental conditions. A single-trap setup was realized. A Faraday cup in the trap tower enabled the proper adjustment of the settings of the beamline connecting the EBIT and the Penning-trap system, resulting in the first trapping of ions at PENTATRAP. A stabilization of switched voltages in the beamline and detailed studies of ion bunch characteristics allowed for reproducible loading of only a few ions. Detection of the axial oscillation of the trapped ions gave hints that in some cases, even single ions had been trapped. Furthermore, valuable conclusions about necessary modifications of the setup could be drawn.

  15. Suspended trapping gas chromatography I fourier transform mass spectrometry for analysis of complex organic mixtures.

    Science.gov (United States)

    Hogan, J D; Laude, D A

    1990-11-01

    The superior sensitivity , dynamic range, and mass measurement accuracy of suspended trapping pulse sequences for gas chromatography combined with Fourier transform mass spectrometry (GC/FTMS) separations of complex organic mixtures is demonstrated. By combining intense ionization conditions with a suspended trapping event prior to detection the working range of the trapped ion cell is increased by 10(3) . Improved detection limits are shown for the GC/FTMS separation of a peppermint oil, with the suspended trapping total ion chromatogram yielding 28 peaks, compared with 15 with a conventional trapping pulse sequence. A fivefold to fifteenfold improvement in signal-to-noise for suspended trapping measurements is also demonstrated with comparison spectra from separations of an unleaded gasoline sample. Suspended trapping spectra show little mass discrimination when an external ion reservoir is used, and chromatographic peak heights differ from conventional spectra by less than 30% if the initial ion population is within the space charge limit of the cell. Finally, average wide band mass measurement errors for components differing in concentration by several orders of magnitude are improved by a factor of 6 to 20 with suspended trapping compared with conventional trapping . For example, average errors of 8.7 ppm are obtained for a suspended trapping GC/FTMS separation of peppermint oil from a single calibration table in which the analysis is perfonned in the absence of calibrant.

  16. First direct mass measurements on nobelium and lawrencium with the Penning trap mass spectrometer SHIPTRAP

    Energy Technology Data Exchange (ETDEWEB)

    Dworschak, Michael Gerhard

    2009-12-08

    The Penning trap mass spectrometer SHIPTRAP at GSI Darmstadt was set up for high-precision mass measurements of heavy radionuclides produced in fusion evaporation reactions and separated from the primary beam by the velocity filter SHIP. It consists of a gas stopping cell for the deceleration of the high energetic reaction products, an RFQ cooler and buncher for cooling and accumulation of the ions, and a double Penning trap system to perform mass measurements. The mass is determined by measuring the cyclotron frequency of the ion of interest in a strong homogeneous magnetic field and comparing it to the frequency of a well-known reference ion. With this method relative uncertainties in the order of 10{sup -8} can be achieved. Recently, mass measurements of the three nobelium isotopes {sup 252-254}No (Z=102) and the lawrencium isotope {sup 255}Lr (Z=103) were performed successfully. These were the first direct mass measurements of transuranium elements ever per- formed. The production rate of the atoms of interest was about one per second or less. The results of the measurements on nobelium confirm the previous mass values which were deduced from Q{sub {alpha}} values. In the case of {sup 255}Lr the mass excess value, which was previously only estimated from systematic trends, was for the first time directly measured. These results mark the first step in the exploration of the region of transuranium elements which is planned at SHIPTRAP. The main objective is to fix the endpoints of {alpha} decay chains which are originating from superheavy elements close to the predicted island of stability. (orig.)

  17. Penning trap for isobaric mass separation at IGISOL

    CERN Document Server

    Kolhinen, V; Hakala, J; Jokinen, A; Kopecky, S; Rinta-Antila, S; Szerypo, J; Äystö, J

    2003-01-01

    A cylindrical Penning trap has been built at the ion guide isotope separator facility IGISOL of the University of Jyvaeskylae. The main goal of the Penning trap application is to purify low-energy radioactive ion beams. The aim is to make isobarically pure beams. The technical description is presented.

  18. Penning trap for isobaric mass separation at IGISOL

    Energy Technology Data Exchange (ETDEWEB)

    Kolhinen, V.S. E-mail: veli.kolhinen@phys.jyu.fi; Eronen, T.; Hakala, J.; Jokinen, A.; Kopecky, S.; Rinta-Antila, S.; Szerypo, J.; Aeystoe, J

    2003-05-01

    A cylindrical Penning trap has been built at the ion guide isotope separator facility IGISOL of the University of Jyvaeskylae. The main goal of the Penning trap application is to purify low-energy radioactive ion beams. The aim is to make isobarically pure beams. The technical description is presented.

  19. The State of the Art of Lethal Oviposition Trap-Based Mass Interventions for Arboviral Control

    Science.gov (United States)

    Johnson, Brian J.; Ritchie, Scott A.; Fonseca, Dina M.

    2017-01-01

    The intensifying expansion of arboviruses highlights the need for effective invasive Aedes control. While mass-trapping interventions have long been discredited as inefficient compared to insecticide applications, increasing levels of insecticide resistance, and the development of simple affordable traps that target and kill gravid female mosquitoes, show great promise. We summarize the methodologies and outcomes of recent lethal oviposition trap-based mass interventions for suppression of urban Aedes and their associated diseases. The evidence supports the recommendation of mass deployments of oviposition traps to suppress populations of invasive Aedes, although better measures of the effects on disease control are needed. Strategies associated with successful mass-trap deployments include: (1) high coverage (>80%) of the residential areas; (2) pre-intervention and/or parallel source reduction campaigns; (3) direct involvement of community members for economic long-term sustainability; and (4) use of new-generation larger traps (Autocidal Gravid Ovitrap, AGO; Gravid Aedes Trap, GAT) to outcompete remaining water-holding containers. While to the best of our knowledge all published studies so far have been on Ae. aegypti in resource-poor or tropical settings, we propose that mass deployment of lethal oviposition traps can be used for focused cost-effective control of temperate Ae. albopictus pre-empting arboviral epidemics and increasing participation of residents in urban mosquito control. PMID:28075354

  20. The State of the Art of Lethal Oviposition Trap-Based Mass Interventions for Arboviral Control

    Directory of Open Access Journals (Sweden)

    Brian J. Johnson

    2017-01-01

    Full Text Available The intensifying expansion of arboviruses highlights the need for effective invasive Aedes control. While mass-trapping interventions have long been discredited as inefficient compared to insecticide applications, increasing levels of insecticide resistance, and the development of simple affordable traps that target and kill gravid female mosquitoes, show great promise. We summarize the methodologies and outcomes of recent lethal oviposition trap-based mass interventions for suppression of urban Aedes and their associated diseases. The evidence supports the recommendation of mass deployments of oviposition traps to suppress populations of invasive Aedes, although better measures of the effects on disease control are needed. Strategies associated with successful mass-trap deployments include: (1 high coverage (>80% of the residential areas; (2 pre-intervention and/or parallel source reduction campaigns; (3 direct involvement of community members for economic long-term sustainability; and (4 use of new-generation larger traps (Autocidal Gravid Ovitrap, AGO; Gravid Aedes Trap, GAT to outcompete remaining water-holding containers. While to the best of our knowledge all published studies so far have been on Ae. aegypti in resource-poor or tropical settings, we propose that mass deployment of lethal oviposition traps can be used for focused cost-effective control of temperate Ae. albopictus pre-empting arboviral epidemics and increasing participation of residents in urban mosquito control.

  1. Verifying the accuracy of the TITAN Penning-trap mass spectrometer

    CERN Document Server

    Brodeur, M; Brunner, T; Ettenauer, S; Gallant, A T; Simon, V V; Smith, M J; Lapierre, A; Ringle, R; Delheij, P; Good, M; Lunney, D; Dilling, J

    2011-01-01

    TITAN (TRIUMF's Ion Traps for Atomic and Nuclear science) is an online facility designed to carry out high-precision mass measurements on singly and highly charged radioactive ions. The TITAN Penning trap has been built and optimized in order to perform such measurements with an accuracy in the sub ppb-range. A detailed characterization of the TITAN Penning trap is presented and a new compensation method is derived and demonstrated, verifying the performance in the range of sub-ppb.

  2. The kick-out mass selection technique for ions stored in an Electrostatic Ion Beam Trap

    Energy Technology Data Exchange (ETDEWEB)

    Toker, Y; Altstein, N; Aviv, O; Rappaport, M L; Heber, O; Schwalm, D; Strasser, D; Zajfman, D [Department of Particle Physics, Weizmann Institute of Science, Rehovot, 76100 (Israel)], E-mail: jtoker@weizmann.ac.il

    2009-09-15

    A simple mass selection technique which allows one to clean a keV ion beam of undesirable masses while stored in an Electrostatic Ion Beam Trap (EIBT) is described. The technique is based on the time-of-flight principle and takes advantage of the long storage times and self-bunching that are possible in this type of traps (self bunching being the effect that keeps ions of the same mass bunched in spite of their finite distributions of velocities and trajectories). As the oscillation period is proportional to the square root of the ion mass, bunches containing ions of different masses will separate in space with increasing storage time and can be kicked out by a pulsed deflector mounted inside the trap. A mass selector of this type has been implemented successfully in an EIBT connected to an Even-Lavie supersonic expansion source and is routinely used in ongoing cluster experiments.

  3. Charge Breeding Techniques in an Electron Beam Ion Trap for High Precision Mass Spectrometry at TITAN

    Science.gov (United States)

    MacDonald, T. D.; Simon, M. C.; Bale, J. C.; Chowdhury, U.; Eibach, M.; Gallant, A. T.; Lennarz, A.; Simon, V. V.; Chaudhuri, A.; Grossheim, A.; Kwiatkowski, A. A.; Schultz, B. E.; Dilling, J.

    2012-10-01

    Penning trap mass spectrometry is the most accurate and precise method available for performing atomic mass measurements. TRIUMF's Ion Trap for Atomic and Nuclear science is currently the only facility to couple its Penning trap to a rare isotope facility and an electron beam ion trap (EBIT). The EBIT is a valuable tool for beam preparation: since the precision scales linearly with the charge state, it takes advantage of the precision gained by using highly charged ions. However, this precision gain is contingent on fast and efficient charge breeding. An optimization algorithm has been developed to identify the optimal conditions for running the EBIT. Taking only the mass number and half-life of the isotope of interest as inputs, the electron beam current density, charge breeding time, charge state, and electron beam energy are all specified to maximize this precision. An overview of the TITAN charge breeding program, and the results of charge breeding simulations will be presented.

  4. SMILETRAP - A Penning trap facility for precision mass measurements using highly charged ions

    CERN Document Server

    Bergström, I; Fritioff, T; Douysset, G; Schoenfelder, J; Schuch, R

    2002-01-01

    The precision of mass measurements in a Penning trap increases linearly with the charge of the ion. Therefore we have attached a Penning trap, named SMILETRAP, to the electron beam ion source CRYSIS at MSL. CRYSIS is via an isotope separator connected to an ion source that can deliver singly charged ions of practically any element. In CRYSIS charge state breeding occurs by intense electron bombardment. We have shown that it is possible to produce, catch and measure the cyclotron frequencies of ions in the charge region 1+ to 52+. The relevant observable in mass measurements using a Penning trap is the ratio of the cyclotron frequencies of the ion of interest and ion used as a mass reference. High precision requires that the two frequencies are measured after one another in the shortest possible time. For reasons of convenience the precision trap operates at room temperature. So far it has been believed that warm traps working at 4 K are required for high mass precision with exactly one ion in the trap at a ti...

  5. Simultaneous measurement of mass and rotation of trapped absorbing particles in air

    CERN Document Server

    Bera, Sudipta K; Sil, Souvik; Saha, Tushar Kanti; Saha, Tanumoy; Banerjee, Ayan

    2016-01-01

    We trap absorbing micro-particles in air by photophoretic forces generated using a single loosely focused Gaussian trapping beam. We measure a component of the radial Brownian motion of a trapped particle cluster and determine the power spectral density, mean squared displacement, and normalized position and velocity autocorrelation functions in order to characterize the photophoretic body force in a quantitative fashion for the first time. The trapped particles also undergo spontaneous rotation due to the action of this force. This is evident from the spectral density that displays clear peaks at the rotation and the particles' inertial resonance frequencies. We fit the spectral density to the well-known analytical function derived from the Langevin equation, measure the resonance and rotation frequencies and determine values for particle mass that we verify at different trapping laser powers with reasonable accuracy.

  6. Ion sponge: a 3-dimentional array of quadrupole ion traps for trapping and mass-selectively processing ions in gas phase.

    Science.gov (United States)

    Xu, Wei; Li, Linfan; Zhou, Xiaoyu; Ouyang, Zheng

    2014-05-01

    In this study, the concept of ion sponge has been explored for developing 3D arrays of large numbers of ion traps but with simple configurations. An ion sponge device with 484 trapping units in a volume of 10 × 10 × 3.2 cm has been constructed by simply stacking 9 meshes together. A single rf was used for trapping ions and mass-selective ion processing. The ion sponge provides a large trapping capacity and is highly transparent for transfer of ions, neutrals, and photons for gas phase ion processing. Multiple layers of quadrupole ion traps, with 121 trapping units in each layer, can operate as a single device for MS or MS/MS analysis, or as a series of mass-selective trapping devices with interlayer ion transfers facilitated by AC and DC voltages. Automatic sorting of ions to different trapping layers based on their mass-to-charge (m/z) ratios was achieved with traps of different sizes. Tandem-in-space MS/MS has also been demonstrated with precursor ions and fragment ions trapped in separate locations.

  7. Evaluation of ion trap mass spectrometry for the determination of ambient nicotine

    Energy Technology Data Exchange (ETDEWEB)

    Wise, M.B.; Higgins, C.E.; Ilgner, R.H.; Guerin, M.R.

    1989-01-01

    A thermal desorption unit has been interfaced directly with a Finnigan Ion Trap mass spectrometer (ITMS) for the identification and quantification of trace organics in air. No chromatographic separation of the desorbed constituents is performed prior to introduction into the mass spectrometer. Instead, positive identification of a compound is made based on its collision induced dissociation (CID) tandem (MS/MS) mass spectrum. Using this technique, as little as 50 pg of a constituent desorbed from resin trap can be characterized and quantified with a sample turnaround time of only 2--3 minutes. 3 refs.

  8. JYFLTRAP: a penning trap for precision mass spectroscopy and isobaric purification

    Energy Technology Data Exchange (ETDEWEB)

    Eronen, T.; Kolhinen, V.S.; Elomaa, V.V.; Gorelov, D.; Hager, U.; Hakala, J.; Jokinen, A.; Kankainen, A.; Karvonen, P.; Kopecky, S.; Moore, I.D.; Penttilae, H.; Rahaman, S.; Rinta-Antila, S.; Rissanen, J.; Saastamoinen, A.; Szerypo, J.; Weber, C.; Aeystoe, J. [University of Jyvaeskylae, Jyvaeskylae (Finland)

    2012-04-15

    In this article a comprehensive description and performance of the double Penning-trap setup JYFLTRAP will be detailed. The setup is designed for atomic mass measurements of both radioactive and stable ions and additionally serves as a very high-resolution mass separator. The setup is coupled to the IGISOL facility at the accelerator laboratory of the University of Jyvaeskylae. The trap has been online since 2003 and it was shut down in the summer of 2010 for relocation to the upgraded IGISOL facility. Numerous atomic mass and decay energy measurements have been performed using the time-of-flight ion-cyclotron resonance technique. The trap has also been used in several decay spectroscopy experiments as a high-resolution mass filter. (orig.)

  9. Off-resonance energy absorption in a linear Paul trap due to mass selective resonant quenching

    Energy Technology Data Exchange (ETDEWEB)

    Sivarajah, I.; Goodman, D. S.; Wells, J. E.; Smith, W. W. [Department of Physics, University of Connecticut, Storrs, Connecticut 06269 (United States); Narducci, F. A. [Naval Air Systems Command, EO Sensors Division, Bldg 2187, Suite 3190 Patuxent River, Maryland 20670 (United States)

    2013-11-15

    Linear Paul traps (LPT) are used in many experimental studies such as mass spectrometry, atom-ion collisions, and ion-molecule reactions. Mass selective resonant quenching (MSRQ) is implemented in LPT either to identify a charged particle's mass or to remove unwanted ions from a controlled experimental environment. In the latter case, MSRQ can introduce undesired heating to co-trapped ions of different mass, whose secular motion is off resonance with the quenching ac field, which we call off-resonance energy absorption (OREA). We present simulations and experimental evidence that show that the OREA increases exponentially with the number of ions loaded into the trap and with the amplitude of the off-resonance external ac field.

  10. Trapping planets in an evolving protoplanetary disk: preferred time, locations and planet mass

    CERN Document Server

    Baillié, Kévin; Pantin, Éric

    2016-01-01

    Planet traps are necessary to prevent forming planets from falling onto their host star by type I migration. Surface mass density and temperature gradient irregularities favor the apparition of traps and deserts. Such features are found at the dust sublimation lines and heat transition barriers. We study how planets may remain trapped or escape as they grow and as the disk evolves. We model the temporal viscous evolution of a protoplanetary disk by coupling its dynamics, thermodynamics, geometry and composition. The resulting mid-plane density and temperature profiles allow the modeling of the interactions of such an evolving disk with potential planets, even before the steady state is reached. We follow the viscous evolution of a MMSN and compute the Lindblad and corotation torques that such a disk would exert on potential planets of various masses located within the planetary formation region. We determine the position of planet traps and deserts in relationship with the sublimation lines, shadowed regions ...

  11. Short communication. Incidence of the OLIPE mass-trapping on olive non-target arthropods

    Energy Technology Data Exchange (ETDEWEB)

    Porcel, M.; Ruano, F.; Sanllorente, O.; Caballero, J. A.; Campos, M.

    2009-07-01

    Due to the widespread of mass-trapping systems for Bactrocera oleae (Gmelin) (Diptera: Tephritidae) control in organic olive cropping, an assessment of the impact on arthropods of the olive agroecosystem was undertaken for the OLIPE trap type. The sampling was carried out in Los Pedroches valley (Cordoba, southern Spain) in three different organic orchard sites. Six OLIPE traps baited with diammonium phosphate were collected from each site (18 in total) from July to November 2002 every 15 days on average. Additionally, in the latest sampling dates, half the traps were reinforced with pheromone to assess its impact on non-target arthropods. From an average of 43.0 catches per trap (cpt) of non-target arthropods during the whole sampling period, the highest number of captures corresponds to the Order Diptera (that represents a 68.5%), followed distantly by the family Formicidae (12.9%) and the Order Lepidoptera (10.4%). Besides the impact on ant populations, other beneficial groups were recorded such as parasitoids (Other Hymenoptera: 2.6%) and predators (Araneae: 1.0%; Neuroptera s.l.: 0.4%). Concerning the temporal distribution of catches, total captures peaked on July and had a slight increase at the beginning of autumn. No significant differences were observed between traps with and without pheromone. The results evidence that a considerable amount of non-specific captures could be prevented by improving the temporal planning of the mass-trapping system. (Author) 25 refs.

  12. LEBIT II: Upgrades and developments for high precision Penning trap mass measurements with rare isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Redshaw, M., E-mail: redsh1m@cmich.edu [Department of Physics, Central Michigan University, Mount Pleasant, MI 48859 (United States); Bollen, G.; Bustabad, S.; Kwiatkowski, A.A.; Lincoln, D.L.; Novario, S.J. [National Superconducting Cyclotron Laboratory, East Lansing, MI 48224 (United States); Department of Physics, Michigan State University, East Lansing, MI 48224 (United States); Ringle, R.; Schwarz, S. [National Superconducting Cyclotron Laboratory, East Lansing, MI 48224 (United States); Valverde, A.A. [National Superconducting Cyclotron Laboratory, East Lansing, MI 48224 (United States); Department of Physics, Michigan State University, East Lansing, MI 48224 (United States)

    2013-12-15

    Highlights: • Development and implementation of new experimental techniques at the Low Energy Beam and Ion Trap (LEBIT) facility at the National Superconducting Cyclotron Laboratory (NSCL). • Development of a laser ablation ion source for the production of carbon clusters for use as mass references and stable isotopes for offline mass measurement programs. • Implementation of stored waveform inverse Fourier transform (SWIFT) for efficient removal of contaminant ions. • Development of a miniature Penning trap to be installed in the LEBIT magnet and used as a magnetometer for monitoring temporal variations in the magnetic field strength. • Development of a new 7 T single-ion Penning trap (SIPT) at the NSCL that will use image charge detection for ultra-high sensitivity measurements of short-lived rare isotopes with very low production rates. -- Abstract: During the next several years and decades the extension of high-precision Penning trap mass spectrometry measurements to more-exotic isotopes, lying far from the valley of stability will continue to provide significant contributions to nuclear physics. However, such measurements must overcome the challenges of working with isotopes that have low production rates and short lifetimes. At the Low Energy Beam and Ion Trap (LEBIT) facility at the National Superconducting Cyclotron Laboratory, a number of developments have been implemented or are underway to meet these challenges by minimizing rare-isotope preparation and measurement time, maximizing use of available beam time, and increasing sensitivity. These developments and the current status of the LEBIT facility will be discussed.

  13. Developments for the HITRAP cooler trap and mass measurements around A = 96 at SHIPTRAP

    Energy Technology Data Exchange (ETDEWEB)

    Koszudowski, Stephen

    2009-07-08

    The HITRAP (Highly charged Ions Trap) facility is currently being set up and commissioned at GSI in Darmstadt. It will provide bunches of 10{sup 5} heavy highly-charged ions, for example hydrogen-like uranium (U{sup 91+}), to high-precision atomic physics experiments. The ions are produced by the GSI accelerator complex and decelerated to 4 MeV/u in the Experimental Storage Ring. Then the ions are decelerated by a two-step linear decelerator down to 6 keV/u. The first deceleration step down to 500 keV/u was successfully commissioned. The decelerated ions are injected into a Penning trap (the Cooler Trap), where they are cooled to 4 K by electron and resistive cooling. Resonant circuits for non-destructive detection and the resistive cooling of the trapped particles were designed and tested. The time control of the trap-cycle (trapping, cooling, extraction) with a time resolution of 25 ns was implemented into the control system CS. CS is also used at the mass measurement Penning trap SHIPTRAP, where the new time control is successfully operated. SHIPTRAP measures radioactive ions stemming from fusion evaporation reactions at the velocity filter SHIP. The masses of 9 nuclides ({sup 93,94,95}Technetium, {sup 94,96}Ruthenium, {sup 95,96,97,98}Rhodium) near the line of stability were precisely measured and compared with the Atomic Mass Evaluation. The detection of isomeric states with the present SHIPTRAP set-up was studied. (orig.)

  14. Development and Deployment of Retrofit PolarisQ Ion Trap Mass Spectrometer for Isotope Ratio Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Cyril V. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Whitten, William B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-11-01

    This report describes Oak Ridge National Laboratory’s (ORNL) FY15 progress in support of National Nuclear Security Administration’s (NNSA) Portable Mass Spectrometer project. A retrofit PolarisQ ion trap mass spectrometer (RPMS) has been assembled from components of two PolarisQ ion trap mass spectrometers used in previous isotope ratio programs. The retrofit mass spectrometer includes a custom Hastelloy vacuum chamber which is about ¼ the size of the standard aluminum vacuum chamber and reduces the instrument weight from the original by nine pounds. In addition, the new vacuum chamber can be independently heated to reduce impurities such as water, which reacts with UF6 to produce HF in the vacuum chamber. The analyzer and all components requiring service are mounted on the chamber lid, facilitating quick and easy replacement of consumable components such as the filament and electron multiplier.

  15. Penning trap mass measurements of $^{99-109}$Cd with the ISOLTRAP mass spectrometer, and implications for the rp process

    CERN Document Server

    Breitenfeldt, M; Beck, D; Blaum, K; George, S; Herfurth, F; Herlert, A; Kellerbauer, A G; Kluge, H-J; Kowalska, M; Lunney, D; Naimi, S; Neidherr, D; Schatz, H; Schwarz, S; Schweikhard, L

    2009-01-01

    Penning trap mass measurements on neutron-deficient Cd isotopes $^{99-109}$Cd have been performed with the ISOLTRAP mass spectrometer at ISOLDE/CERN, all with relative mass uncertainties below $3 \\times 10^{-8}$. A new mass evaluation has been performed. The mass of $^{99}$Cd has been determined for the first time which extends the region of accurately known mass values towards the doubly magic nucleus $^{100}$Sn. The implication of the results on the reaction path of the $rp$ process in stellar X-ray bursts is discussed. In particular, the uncertainty of the abundance and the overproduction created by the $rp$-process for the mass A = 99 is demonstrated by reducing the uncertainty of the proton-separation energy of $^{100}$In $S_{p}(^{100}$In) by a factor of 2.5.

  16. The construction of TRIGA-TRAP and direct high-precision Penning trap mass measurements on rare-earth elements and americium

    Energy Technology Data Exchange (ETDEWEB)

    Ketelaer, Jens

    2010-06-14

    The construction of TRIGA-TRAP and direct high-precision Penning trap mass measurements on rare-earth elements and americium: Nuclear masses are an important quantity to study nuclear structure since they reflect the sum of all nucleonic interactions. Many experimental possibilities exist to precisely measure masses, out of which the Penning trap is the tool to reach the highest precision. Moreover, absolute mass measurements can be performed using carbon, the atomic-mass standard, as a reference. The new double-Penning trap mass spectrometer TRIGA-TRAP has been installed and commissioned within this thesis work, which is the very first experimental setup of this kind located at a nuclear reactor. New technical developments have been carried out such as a reliable non-resonant laser ablation ion source for the production of carbon cluster ions and are still continued, like a non-destructive ion detection technique for single-ion measurements. Neutron-rich fission products will be available by the reactor that are important for nuclear astrophysics, especially the r-process. Prior to the on-line coupling to the reactor, TRIGA-TRAP already performed off-line mass measurements on stable and long-lived isotopes and will continue this program. The main focus within this thesis was on certain rare-earth nuclides in the well-established region of deformation around N {proportional_to} 90. Another field of interest are mass measurements on actinoids to test mass models and to provide direct links to the mass standard. Within this thesis, the mass of {sup 241}Am could be measured directly for the first time. (orig.)

  17. Final Report - Advanced Ion Trap Mass Spectrometry Program - Oak Ridge National Laboratory - Sandia National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Whitten, W.B.

    2002-12-18

    This report covers the three main projects that collectively comprised the Advanced Ion Trap Mass Spectrometry Program. Chapter 1 describes the direct interrogation of individual particles by laser desorption within the ion trap mass spectrometer analyzer. The goals were (1) to develop an ''intelligent trigger'' capable of distinguishing particles of biological origin from those of nonbiological origin in the background and interferent particles and (2) to explore the capability for individual particle identification. Direct interrogation of particles by laser ablation and ion trap mass spectrometry was shown to have good promise for discriminating between particles of biological origin and those of nonbiological origin, although detailed protocols and operating conditions were not worked out. A library of more than 20,000 spectra of various types of biological particles has been assembled. Methods based on multivariate analysis and on neural networks were used to discriminate between particles of biological origin and those of nonbiological origin. It was possible to discriminate between at least some species of bacteria if mass spectra of several hundred similar particles were obtained. Chapter 2 addresses the development of a new ion trap mass analyzer geometry that offers the potential for a significant increase in ion storage capacity for a given set of analyzer operating conditions. This geometry may lead to the development of smaller, lower-power field-portable ion trap mass spectrometers while retaining laboratory-scale analytical performance. A novel ion trap mass spectrometer based on toroidal ion storage geometry has been developed. The analyzer geometry is based on the edge rotation of a quadrupolar ion trap cross section into the shape of a torus. Initial performance of this device was poor, however, due to the significant contribution of nonlinear fields introduced by the rotation of the symmetric ion-trapping geometry. These

  18. Photoassociative Cooling and Trapping of Center-of-Mass Motion of Atom-Pairs

    CERN Document Server

    Saha, Subrata; Deb, Bimalendu

    2015-01-01

    We show that it is possible to cool and trap the center-of-mass (COM) motion of atom-pairs by a lin$\\perp$lin Sisyphus-like method using counter-propagating photoassociation lasers. This method relies on the photoassociative coupling between an excited molecular bound state and a single-channel continuum of states of scattering between ground-state atoms. We demonstrate that one can generate molecular spin-dependent periodic potentials by this method for trapping the COM motion of pairs of ground-state atoms. We illustrate this with numerical calculations using fermionic $^{171}$Yb atoms as an example.

  19. CryoMPET: the Cryogenic Upgrade to TITAN's Mass Measurement Penning Trap

    Science.gov (United States)

    Leistenschneider, Erich; Titan Collaboration

    2016-09-01

    Atomic masses are key tools to understand the nature of nuclear forces. With the availability of beams of very exotic species, mass spectroscopy techniques have become more challenging. They need to be faster, more efficient, and still have to provide high enough precision to be of scientific value. The TITAN facility at TRIUMF has been performing precision mass measurements of radioactive nuclei for almost a decade. Its main equipment, the Measurement Penning Trap (MPET), employs the Time-of-Flight Ion Cyclotron Resonance technique to probe atomic masses of ions living as short as 10ms. A powerful way to increase the precision of such technique is to charge-breed the inspected ion, which, in order to prevent charge state decay through a typical measurement cycle, requires trap's vacuum level to be in the order of 1E-11 Torr. Otherwise, the ion's charge state will most likely decay via electron recapture from the trap's background gas. MPET is being redesigned to perform mass measurements of ions at charge states over +20. It will be integrated into a new cryogenic vacuum system and should be ready for commissioning in 2017. We will present the details of TITAN's new CryoMPET upgrade including its design concept and the status of its development.

  20. Mass measurements of neutron-deficient nuclides close to A=80 with a Penning trap

    Energy Technology Data Exchange (ETDEWEB)

    Kankainen, A.; Elomaa, V.-V.; Eronen, T.; Hager, U.; Hakala, J.; Jokinen, A.; Moore, I.; Penttilae, H.; Peraejaervi, K.; Rahaman, S.; Rinta-Antila, S.; Ronkanen, P.; Saastamoinen, A.; Sonoda, T.; Aeystoe, J. [University of Jyvaeskylae, Department of Physics, P.O. Box 35 (Finland); Batist, L.; Novikov, Yu.N.; Popov, A.V.; Seliverstov, D.M. [Petersburg Nuclear Physics Institute, Gatchina (Russian Federation); Eliseev, S.A.; Vorobjev, G.K. [Petersburg Nuclear Physics Institute, Gatchina (Russian Federation); GSI, Darmstadt (Germany)

    2006-09-15

    The masses of {sup 80,} {sup 81,} {sup 82,} {sup 83}Y, {sup 83,} {sup 84,} {sup 85,} {sup 86,} {sup 88}Zr and {sup 85,} {sup 86,} {sup 87,} {sup 88}Nb have been measured with a typical precision of 7keV by using the Penning trap setup at IGISOL. The mass of {sup 84}Zr has been measured for the first time. These precise mass measurements have improved S{sub p} and Q{sub EC} values for astrophysically important nuclides. (orig.)

  1. Advanced Automation for Ion Trap Mass Spectrometry-New Opportunities for Real-Time Autonomous Analysis

    Science.gov (United States)

    Palmer, Peter T.; Wong, C. M.; Salmonson, J. D.; Yost, R. A.; Griffin, T. P.; Yates, N. A.; Lawless, James G. (Technical Monitor)

    1994-01-01

    The utility of MS/MS for both target compound analysis and the structure elucidation of unknowns has been described in a number of references. A broader acceptance of this technique has not yet been realized as it requires large, complex, and costly instrumentation which has not been competitive with more conventional techniques. Recent advancements in ion trap mass spectrometry promise to change this situation. Although the ion trap's small size, sensitivity, and ability to perform multiple stages of mass spectrometry have made it eminently suitable for on-line, real-time monitoring applications, advance automation techniques are required to make these capabilities more accessible to non-experts. Towards this end we have developed custom software for the design and implementation of MS/MS experiments. This software allows the user to take full advantage of the ion trap's versatility with respect to ionization techniques, scan proxies, and ion accumulation/ejection methods. Additionally, expert system software has been developed for autonomous target compound analysis. This software has been linked to ion trap control software and a commercial data system to bring all of the steps in the analysis cycle under control of the expert system. These software development efforts and their utilization for a number of trace analysis applications will be described.

  2. Purge and trap method to determine alpha factors of VOC liquid-phase mass transfer coefficients

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A theoretical approach and laboratory practice of determining the alpha factors of volatile organic compound (VOC) liquid-phase mass transfer coefficients are present in this study.Using Purge Trap Concentrator, VOC spiked water samples are purged by high-purity nitrogen in the laboratory, the VOC liquid-phase mass transfer rate constants under the laboratory conditions are then obtained by observing the variation of VOCs purged out of the water with the purge time.The alpha factors of VOC liquid-phase mass transfer coefficients are calculated as the ratios of the liquid-phase mass transfer rate constants in real water samples to their counterparts in pure water under the same experimental conditions. This direct and fast approach is easy to control in the laboratory, and would benefit mutual comparison among researchers, so might be useful for thestudy of VOC mass transfer across the liquid-gas interface.

  3. Analysis of VX on soil particles using ion trap secondary ion mass spectrometry.

    Science.gov (United States)

    Groenewold, G S; Appelhans, A D; Gresham, G L; Olson, J E; Jeffery, M; Wright, J B

    1999-07-01

    The direct detection of the nerve agent VX (methylphosphonothioic acid, S-[2-[bis(1-methylethyl)amino]ethyl] O-ethyl ester) on milligram quantities of soil particles has been achieved using ion trap secondary ion mass spectrometry (IT-SIMS). VX is highly adsorptive toward a wide variety of surfaces; this attribute makes detection using gas-phase approaches difficult but renders the compound very amenable to surface detection. An ion trap mass spectrometer, modified to perform SIMS, was employed in the present study. A primary ion beam (ReO4-) was fired on axis through the ion trap, where it impacted the soil particle samples. [VX + H]+, [VX + H]+ fragment ions, and ions from the chemical background were sputtered into the gas-phase environment of the ion trap, where they were either scanned out or isolated and fragmented (MS2). At a surface concentration of 0.4 monolayer, intact [VX + H]+, and its fragment ions, were readily observable above background. However, at lower concentrations, the secondary ion signal from VX became obscured by ions derived from the chemical background on the surface of the soil particles. MS2 analysis using the ion trap was employed to improve detection of lower concentrations of VX: detection of the 34S isotopic ion of [VX + H]+, present at a surface concentration of approximately 0.002 monolayer, was accomplished. The study afforded the opportunity to investigate the fragmentation chemistry of VX. Semiempirical calculations suggest strongly that the molecule is protonated at the N atom. Deuterium labeling showed that formation of the base peak ion (C2H4)N(i-C3H7)2+ involves transfer of the amino proton to the phosphonothioate moiety prior to, or concurrent with, C-S bond cleavage. To manage the risk associated with working with the compound, the vacuum unit of the IT-SIMS was located in a hood, connected by cables to the externally located electronics and computer.

  4. Evaluation of Pulse Counting for the Mars Organic Mass Analyzer (MOMA) Ion Trap Detection Scheme

    Science.gov (United States)

    Van Amerom, Friso H.; Short, Tim; Brinckerhoff, William; Mahaffy, Paul; Kleyner, Igor; Cotter, Robert J.; Pinnick, Veronica; Hoffman, Lars; Danell, Ryan M.; Lyness, Eric I.

    2011-01-01

    The Mars Organic Mass Analyzer is being developed at Goddard Space Flight Center to identify organics and possible biological compounds on Mars. In the process of characterizing mass spectrometer size, weight, and power consumption, the use of pulse counting was considered for ion detection. Pulse counting has advantages over analog-mode amplification of the electron multiplier signal. Some advantages are reduced size of electronic components, low power consumption, ability to remotely characterize detector performance, and avoidance of analog circuit noise. The use of pulse counting as a detection method with ion trap instruments is relatively rare. However, with the recent development of high performance electrical components, this detection method is quite suitable and can demonstrate significant advantages over analog methods. Methods A prototype quadrupole ion trap mass spectrometer with an internal electron ionization source was used as a test setup to develop and evaluate the pulse-counting method. The anode signal from the electron multiplier was preamplified. The an1plified signal was fed into a fast comparator for pulse-level discrimination. The output of the comparator was fed directly into a Xilinx FPGA development board. Verilog HDL software was written to bin the counts at user-selectable intervals. This system was able to count pulses at rates in the GHz range. The stored ion count nun1ber per bin was transferred to custom ion trap control software. Pulse-counting mass spectra were compared with mass spectra obtained using the standard analog-mode ion detection. Prelin1inary Data Preliminary mass spectra have been obtained for both analog mode and pulse-counting mode under several sets of instrument operating conditions. Comparison of the spectra revealed better peak shapes for pulse-counting mode. Noise levels are as good as, or better than, analog-mode detection noise levels. To artificially force ion pile-up conditions, the ion trap was overfilled

  5. Correlation between y-type ions observed in ion trap and triple quadrupole mass spectrometers.

    Science.gov (United States)

    Sherwood, Carly A; Eastham, Ashley; Lee, Lik Wee; Risler, Jenni; Vitek, Olga; Martin, Daniel B

    2009-09-01

    Multiple reaction monitoring mass spectrometry (MRM-MS) is a technique for high-sensitivity targeted analysis. In proteomics, MRM-MS can be used to monitor and quantify a peptide based on the production of expected fragment peaks from the selected peptide precursor ion. The choice of which fragment ions to monitor in order to achieve maximum sensitivity in MRM-MS can potentially be guided by existing MS/MS spectra. However, because the majority of discovery experiments are performed on ion trap platforms, there is concern in the field regarding the generalizability of these spectra to MRM-MS on a triple quadrupole instrument. In light of this concern, many operators perform an optimization step to determine the most intense fragments for a target peptide on a triple quadrupole mass spectrometer. We have addressed this issue by targeting, on a triple quadrupole, the top six y-ion peaks from ion trap-derived consensus library spectra for 258 doubly charged peptides from three different sample sets and quantifying the observed elution curves. This analysis revealed a strong correlation between the y-ion peak rank order and relative intensity across platforms. This suggests that y-type ions obtained from ion trap-based library spectra are well-suited for generating MRM-MS assays for triple quadrupoles and that optimization is not required for each target peptide.

  6. Precision Comparison of $\\bar{p}$ and $ p $ Masses in a Penning Trap

    CERN Multimedia

    2002-01-01

    PS196 : Precision Comparison of $\\bar{p}$ and p Masses in a Penning Trap For the first time, antiprotons with energies 10$^{10}$ times lower than those in LEAR can be stored and studied over long times in a small apparatus. The first measurement at this new, low energy frontier is a 1000-fold improvement in the measured antiproton mass. The mass dependent cyclotron frequencies, first for antiprotons then for protons orbiting in the same magnetic field, are compared to establish that the antiproton and proton masses are the same to at least 4~parts in 10$^8$. This is the most stringent test of whether a baryon system is invariant under CPT transformations. A special trap geometry and a superconducting solenoid which cancels fluctuations in the magnetic field in the accelerator hall were crucial to this greatly improved measurement. The current objective is to improve the precision by one or two orders of magnitude. Antiprotons from LEAR at 5.9~MeV, slow below 3~keV via collisions in a thin metal window, and ar...

  7. MEMS Fabrication of Micro Cylindrical Ion Trap Mass Spectrometer for CubeSats Application

    Science.gov (United States)

    Zheng, Y.

    2015-10-01

    Microelectromechanical Systems (MEMS) technology is used to fabricate arrays of micro Cylindrical Ion Traps (μCIT) which are integrated into a miniaturized mass spectrometer (MS). The micro μCITs are built from silicon wafers and requires high machining precision, smooth surface, and high dimensional uniformity across the array for optimum mass spectrometer performance. In order to build these 3D miniature structures several MEMS processing techniques were explored and a process was developed and tested. By using the developed MEMS process, the required μCIT 4 x 4 arrays were fabricated. This included a chip design variation in which mechanical locking pits and posts were machined in the Ring Electrode (RE) chip and End Plate (EP) chips respectively, for self-assembly. The size of the assembled μCIT is only 12 mm x 12 mm x 1.5 mm. It is a key component for the miniature mass spectrometer. The micro cylindrical ion trap mass spectrometer has the advantages of low-power operation, simpler electronics and less-stringent vacuum system requirements. The MEMS batch production capabilities will also greatly lower the cost. It is a promising candidate for CubeSat and nanoSats applications for exploration of chemical distributions in space.

  8. Nuclear structure research with the Penning-trap mass spectrometer ISOLTRAP at CERN

    Energy Technology Data Exchange (ETDEWEB)

    Neidherr, Dennis [Johannes Gutenberg-Universitaet, Mainz (Germany)

    2009-07-01

    At the double-Penning-trap mass spectrometer ISOLTRAP at ISOLDE/CERN the cyclotron frequency of short-lived radionuclides is measured in order to determine their mass with a relative uncertainty in the order of 10{sup -8} and below. This ground state property plays an important role in many fields of modern physics from nuclear-structure research to nuclear astrophysics and tests of the weak interaction of the Standard Model. An example for the first one is the evolution of the nuclear shape as a function of the number of neutrons and protons. In 2008 the masses of {sup 223-229}Rn and {sup 143-146}Xe were measured for the first time directly, whereas {sup 229}Rn was even discovered by our Penning trap based experiment. With this mass values one can study the proton-neutron interaction and therefore get information about the nuclear structure like collectivity, the onset of deformation or the geometrical shapes in atomic nuclei. The experimental results as well as the impact on the theoretical models will be presented.

  9. Characterization of phosphoantigens by high-performance anion-exchange chromatography-electrospray ionization ion trap mass spectrometry and nanoelectrospray ionization ion trap mass spectrometry.

    Science.gov (United States)

    Pont, F; Luciani, B; Belmant, C; Fournié, J J

    2001-08-01

    New phosphorylated microbial metabolites referred to as phosphoantigens activate immune responses in humans. Although these molecules have leading applications in medical research, no direct method allows their rapid and unambiguous structural identification. Here, we interfaced online HPAEC (high performance anion-exchange chromatography) with ESI-ITMS (electrospray ionization ion trap mass spectrometry) to identify such pyrophosphorylated molecules. A self-regenerating anion suppressor located upstream of electrospray ionization enabled the simultaneous detection of pyrophosphoester by conductimetry, UV and MS. By HPAEC-ITMS and HPAEC-ITMS2, a single run permitted characterization of reference phosphoantigens and of related structures. Although all compounds were resolved by HPAEC, MS enabled their detection and identification by [M-H]- and fragment ions. Isobaric phosphoantigen analogues were also separated by HPAEC and distinguished by MS2. The relevance of this device was demonstrated for phosphoantigens analysis in human urine and plasma. Furthermore, identification of natural phosphoantigens by automatically generated 2D mass spectra from nano-ESI-ITMS is presented. This last technique permits the simultaneous performance of molecular screening of natural phosphoantigen extracts and their identification.

  10. Estimation of trapped mass by in-cylinder pressure resonance in HCCI engines

    Science.gov (United States)

    Luján, José Manuel; Guardiola, Carlos; Pla, Benjamín; Bares, Pau

    2016-01-01

    High pressure gradients at homogeneous charge compression ignition (HCCI) engines heavily excite the pressure resonance. The pressure resonant frequency depends on speed of sound in the cylinder, and thus on the bulk gas temperature. Present paper profits this relation estimating the trapped mass inside the cylinder. In contrast to other estimation methods in the literature, the presented method is based on the trace of the in-cylinder pressure during the cycle; therefore, it permits a cycle-to-cycle mass estimation, and avoids errors associated with other assumptions, such as heat transfer during compression or initial temperature of the in-cylinder gases. The proposed strategy only needs the pressure signal, a volume estimation and a composition assumption to obtain several trapped mass estimates during one cycle. These estimates can be later combined for providing an error estimate of the measurement, with the assumption of negligible blow-by. The method is demonstrated in two HCCI engines of different size, showing good performance in steady operation and presenting great potential to control transient operation.

  11. Electron Flood Charge Compensation Device for Ion Trap Secondary Ion Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Appelhans, Anthony David; Ward, Michael Blair; Olson, John Eric

    2002-11-01

    During secondary ion mass spectrometry (SIMS) analyses of organophosphorous compounds adsorbed onto soils, the measured anion signals were lower than expected and it was hypothesized that the low signals could be due to sample charging. An electron flood gun was designed, constructed and used to investigate sample charging of these and other sample types. The flood gun was integrated into one end cap of an ion trap secondary ion mass spectrometer and the design maintained the geometry of the self-stabilizing extraction optics used in this instrument. The SIMION ion optics program was used to design the flood gun, and experimental results agreed with the predicted performance. Results showed the low anion signals from the soils were not due to sample charging. Other insulating and conducting samples were tested using both a ReO4- and a Cs+ primary ion beam. The proximity of the sample and electron source to the ion trap aperture resulted in generation of background ions in the ion trap via electron impact (EI) ionization during the period the electron gun was flooding the sample region. When using the electron gun with the ReO4- primary beam, the required electron current was low enough that the EI background was negligible; however, the high electron flood current required with the Cs+ beam produced background EI ions that degraded the quality of the mass spectra. The consequences of the EI produced cations will have to be evaluated on a sample-by-sample basis when using electron flood. It was shown that the electron flood gun could be intentionally operated to produce EI spectra in this instrument. This offers the opportunity to measure, nearly simultaneously, species evaporating from a sample, via EI, and species bound to the surface, via SIMS.

  12. Comparison of quadrupole and ion trap mass spectrometry for the analysis of polychlorinated biphenyls

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, E.; DeVita, W. [Univ. of Wisconsin, Stevens Point, WI (United States)

    1995-12-31

    Polychlorinated biphenyls (PCBs) are often analyzed using gas chromatography with an electron capture detector (GC/ECD) because of the sensitivity of this detection technique toward this class of compounds. However, use of gas chromatography/mass spectrometry (GC/MS) can provide additional selectivity, thus minimizing the likelihood of false positive results from interfering compounds. GC/MS provides a higher degree of confidence in the identification of the chromatographic peaks, but is often limited, in comparison to GC/ECL, by its sensitivity. The two most common mass analyzers used are quadrupole and ion trap detectors. In this study the authors propose to document the capabilities of both quadrupole and ion trap analyzer for analysis of PCBs. They will compare and contrast the sensitivities and linear ranges for these compounds. Sensitivities will be assessed by signal-to-noise ratio comparisons. Linearity of the calibrated range will also be investigated through evaluation of the relative response factors versus concentration of PCB for a fixed concentration of internal standard. Estimations will be made of the appropriate linear ranges on the two instruments and comparisons made in both the full scan and selected ion modes.

  13. Direct sampling ion trap mass spectrometry (DSITMS). Innovative technology summary report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-01

    This report describes the cost, performance, and other key characteristics of an innovative technology for determining the presence or absence, and measuring the concentration, of volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs) in groundwater and soil, and in gaseous remediation process streams at hazardous waste sites. This new technology is Direct Sampling Ion Trap Mass Spectrometry (DSITMS). DSITMS introduces sample materials directly into an ion trap mass spectrometer by means of a very simple interface, such as a capillary restrictor or a polymer membrane. There is typically very little, if any, sample preparation and no chromatographic separation of the sample constituents. This means that the response of the instrument to the analytes or contaminants in a sample is nearly instantaneous, and that analytical methods based on DSITMS are fast. Analyses are typically completed in less than five minutes, and the analysis cost is generally 50% or less than the amount charged by commercial laboratories using Environmental Protection Agency (EPA) analysis methods.

  14. The Siberian Traps and the End-Permian mass extinction: a critical review

    Institute of Scientific and Technical Information of China (English)

    Andy SAUNDERS; Marc REICHOW

    2009-01-01

    The association between the Siberian Traps,the largest continental flood basalt province,and thelargest-known mass extinction event at the end of the Permian period,has been strengthened by re-cently-published high-precision 40Ar/39Ar dates from widespread localities across the Siberian prov-ince[i].We argue that the impact of the volcanism was amplified by the prevailing late Permian envi-ronmental conditions-in particular,the hothouse climate,with sluggish oceanic circulation,that wasleading to widespread oceanic anoxia.Volcanism released large masses of sulphate aerosols andcarbon dioxide,the former triggering short-duration volcanic winters,the latter leading to long-termwarming.Whilst the mass of CO2 released from individual eruptions was small compared with the totalmass of carbon in the atmosphere-ocean system,the long 'mean lifetime' of atmospheric C02,com-pared with the eruption flux and duration,meant that significant accumulation could occur over periodsof 10s years.Compromise of the carbon sequestration systems (by curtailment of photosynthesis,de-struction of biomass,and warming and acidification of the oceans) probably led to rapid atmosphericCO2 build-up,warming,and shallow-water anoxia,leading ultimately to mass extinction.

  15. Infrared ion spectroscopy in a modified quadrupole ion trap mass spectrometer at the FELIX free electron laser laboratory

    Science.gov (United States)

    Martens, Jonathan; Berden, Giel; Gebhardt, Christoph R.; Oomens, Jos

    2016-10-01

    We report on modifications made to a Paul-type quadrupole ion trap mass spectrometer and discuss its application in infrared ion spectroscopy experiments. Main modifications involve optical access to the trapped ions and hardware and software coupling to a variety of infrared laser sources at the FELIX infrared free electron laser laboratory. In comparison to previously described infrared ion spectroscopy experiments at the FELIX laboratory, we find significant improvements in efficiency and sensitivity. Effects of the trapping conditions of the ions on the IR multiple photon dissociation spectra are explored. Enhanced photo-dissociation is found at lower pressures in the ion trap. Spectra obtained under reduced pressure conditions are found to more closely mimic those obtained in the high-vacuum conditions of an Fourier transform ion cyclotron resonance mass spectrometer. A gas-mixing system is described enabling the controlled addition of a secondary gas into helium buffer gas flowing into the trap and allows for ion/molecule reactions in the trap. The electron transfer dissociation (ETD) option of the mass spectrometer allows for IR structure characterization of ETD-generated peptide dissociation products.

  16. Development of a Linear Ion Trap Mass Spectrometer (LITMS) Investigation for Future Planetary Surface Missions

    Science.gov (United States)

    Brinckerhoff, W.; Danell, R.; Van Ameron, F.; Pinnick, V.; Li, X.; Arevalo, R.; Glavin, D.; Getty, S.; Mahaffy, P.; Chu, P.; Zacny, K.; Rogacki, S.; Grubisic, A.; Cornish, T.

    2014-01-01

    Future surface missions to Mars and other planetary bodies will benefit from continued advances in miniature sensor and sample handling technologies that enable high-performance chemical analyses of natural samples. Fine-scale (approx.1 mm and below) analyses of rock surfaces and interiors, such as exposed on a drill core, will permit (1) the detection of habitability markers including complex organics in association with their original depositional environment, and (2) the characterization of successive layers and gradients that can reveal the time-evolution of those environments. In particular, if broad-based and highly-sensitive mass spectrometry techniques could be brought to such scales, the resulting planetary science capability would be truly powerful. The Linear Ion Trap Mass Spectrometer (LITMS) investigation is designed to conduct fine-scale organic and inorganic analyses of short (approx.5-10 cm) rock cores such as could be acquired by a planetary lander or rover arm-based drill. LITMS combines both pyrolysis/gas chromatograph mass spectrometry (GCMS) of sub-sampled core fines, and laser desorption mass spectrometry (LDMS) of the intact core surface, using a common mass analyzer, enhanced from the design used in the Mars Organic Molecule Analyzer (MOMA) instrument on the 2018 ExoMars rover. LITMS additionally features developments based on the Sample Analysis at Mars (SAM) investigation on MSL and recent NASA-funded prototype efforts in laser mass spectrometry, pyrolysis, and precision subsampling. LITMS brings these combined capabilities to achieve its four measurement objectives: (1) Organics: Broad Survey Detect organic molecules over a wide range of molecular weight, volatility, electronegativity, concentration, and host mineralogy. (2) Organic: Molecular Structure Characterize internal molecular structure to identify individual compounds, and reveal functionalization and processing. (3) Inorganic Host Environment Assess the local chemical

  17. Quantification of Fumaria officinalis isoquinoline alkaloids by nonaqueous capillary electrophoresis-electrospray ion trap mass spectrometry.

    Science.gov (United States)

    Sturm, Sonja; Strasser, Eva-Maria; Stuppner, Hermann

    2006-04-21

    A capillary electrophoresis (CE) method using non-aqueous (NA) separation solutions combined with an ion trap mass spectrometer (MS and MS/MS) as detection device is presented for the separation, identification and quantification of isoquinoline alkaloids from Fumaria officinalis. The best results were obtained with a mixture of acetonitrile-methanol (9:1, v/v) containing 60mM ammonium acetate and 2.2M acetic acid as running electrolyte and an applied voltage of 30 kV. Electrospray MS measurements were performed in the positive ionization mode with isopropanol-water (1:1, v/v) as sheath liquid at a flow rate of 3 microl/min. Alkaloids were detected as [M+H](+)-ions and showed typical fragmentation patterns in MS/MS experiments. The developed assay was used for the quantification of seven isoquinoline alkaloids representing different structural subtypes in Fumariae herba extracts and F. herba containing phytopharmaceuticals.

  18. Characterization of environmental samples using ion trap-secondary ion mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Groenewold, G.S.; Appelhans, A.D.; Ingram, J.C.

    1998-02-01

    The detection of chemical warfare agent residues on environmental surfaces is an important analytical activity because of the potential for proliferation of these weapons, and for environmental monitoring in areas where they are stored. Historically, one of the most widely used agents has been bis(2-chloroethyl) sulfide, also known as mustard gas and HD. It was initially used in combat in 1917; by the end of the First World War, more than 16% of all casualties were due to chemicals, in most cases mustard. Manufacture of mustard is continuing to this day; consequently, there are ongoing opportunities for exposure. 2-Chloroethyl ethyl sulfide (CEES) is used as a simulant for mustard (HD) in a study to develop secondary ion mass spectrometry (SIMS) for rapid, semi-quantitative detection of mustard on soil. Using SIMS with single stage mass spectrometry, a signature for CEES can be unequivocally observed only at the highest concentrations (0.1 monolayer and above). Selectivity and sensitivity are markedly improved employing multiple-stage mass spectrometry using an ion trap. C{sub 2}H{sub 5}SC{sub 2}H{sub 4}{sup +} from CEES eliminates C{sub 2}H{sub 4} and H{sub 2}S, which are highly diagnostic. CEES was detected at 0.0012 monolayer on soil. A single analysis could be conducted in under 5 minutes.

  19. Real-Time Quantitative Analysis of H2, He, O2, and Ar by Quadrupole Ion Trap Mass Spectrometry

    Science.gov (United States)

    Ottens, Andrew K.; Harrison, W. W.; Griffin, Timothy P.; Helms, William R.; Voska, N. (Technical Monitor)

    2002-01-01

    The use of a quadrupole ion trap mass spectrometer for quantitative analysis of hydrogen and helium as well as other permanent gases is demonstrated. The customized instrument utilizes the mass selective instability mode of mass analysis as with commercial instruments; however, this instrument operates at a greater RF trapping frequency and without a buffer gas. With these differences, a useable mass range from 2 to over 50 Da is achieved, as required by NASA for monitoring the Space Shuttle during a launch countdown. The performance of the ion trap is evaluated using part-per-million concentrations of hydrogen, helium, oxygen and argon mixed into a nitrogen gas stream. Relative accuracy and precision when quantitating the four analytes were better than the NASA-required minimum of 10% error and 5% deviation, respectively. Limits of detection were below the NASA requirement of 25-ppm hydrogen and 100-ppm helium; those for oxygen and argon were slightly higher than the requirement. The instrument provided adequate performance at fast data recording rates, demonstrating the utility of an ion trap mass spectrometer as a real-time quantitative monitoring device for permanent gas analysis.

  20. First Use of High Charge States for Mass Measurements of Short-lived Nuclides in a Penning Trap

    CERN Document Server

    Ettenauer, S; Gallant, A T; Brunner, T; Chowdhury, U; Simon, V V; Brodeur, M; Chaudhuri, A; Mané, E; Andreoiu, C; Audi, G; López-Urrutia, J R Crespo; Delheij, P; Gwinner, G; Lapierre, A; Lunney, D; Pearson, M R; Ringle, R; Ullrich, J; Dilling, J

    2011-01-01

    Penning trap mass measurements of short-lived nuclides have been performed for the first time with highly-charged ions (HCI), using the TITAN facility at TRIUMF. Compared to singly-charged ions, this provides an improvement in experimental precision that scales with the charge state q. Neutron-deficient Rb-isotopes have been charge bred in an electron beam ion trap to q = 8 - 12+ prior to injection into the Penning trap. In combination with the Ramsey excitation scheme, this unique setup creating low energy, highly-charged ions at a radioactive beam facility opens the door to unrivalled precision with gains of 1-2 orders of magnitude. The method is particularly suited for short-lived nuclides such as the superallowed {\\beta} emitter 74Rb (T1/2 = 65 ms). The determination of its atomic mass and an improved QEC-value are presented.

  1. Degradation study of enniatins by liquid chromatography-triple quadrupole linear ion trap mass spectrometry.

    Science.gov (United States)

    Serrano, A B; Meca, G; Font, G; Ferrer, E

    2013-12-15

    Enniatins A, A1, B and B1 (ENs) are mycotoxins produced by Fusarium spp. and are normal contaminants of cereals and derivate products. In this study, the stability of ENs was evaluated during food processing by simulation of pasta cooking. Thermal treatments at different incubation times (5, 10 and 15 min) and different pH (4, 7 and 10) were applied in an aqueous system and pasta resembling system (PRS). The concentrations of the targeted mycotoxins were determined using liquid chromatography coupled to tandem mass spectrometry. High percentages of ENs reduction (81-100%) were evidenced in the PRS after the treatments at 5, 10 and 15 min of incubation. In contrast to the PRS, an important reduction of the ENs was obtained in the aqueous system after 15 min of incubation (82-100%). In general, no significant differences were observed between acid, neutral and basic solutions. Finally, several ENs degradation products were identified using the technique of liquid chromatography-triple quadrupole linear ion trap mass spectrometry.

  2. Profiling of lipid species by normal-phase liquid chromatography, nanoelectrospray ionization, and ion trap-orbitrap mass spectrometry

    DEFF Research Database (Denmark)

    Sokol, Elena; Almeida, Reinaldo; Hannibal-Bach, Hans Kristian

    2013-01-01

    Detailed analysis of lipid species can be challenging due to their structural diversity and wide concentration range in cells, tissues, and biofluids. To address these analytical challenges, we devised a reproducible, sensitive, and integrated lipidomics workflow based on normal-phase liquid...... chromatography-Fourier transform mass spectrometry (LC-FTMS) and LC-ITMS(2) (ion trap tandem mass spectrometry) for profiling and structural analysis of lipid species. The workflow uses a normal-phase LC system for efficient separation of apolar and polar lipid species combined with sensitive and specific...... analysis powered by a chip-based nanoelectrospray ion source and a hybrid ion trap-orbitrap mass spectrometer. The workflow was executed using a primary LC-FTMS survey routine for identification and profiling of lipid species based on high-mass accuracy and retention time followed by a targeted LC-ITMS(2...

  3. Field evaluation of Mediterranean fruit fly mass trapping with Tripack as alternative to malathion bait-spraying in citrus orchards

    Energy Technology Data Exchange (ETDEWEB)

    Mediouni Ben Jemaa, J.; Bachrouch, O.; Allimi, E.; Dhouibi, M. H.

    2010-07-01

    The mass trapping technique based on the use of the female-targeted attractant lure Tri-pack as an alternative to malathion bait-spraying (control treatment) was tested in two citrus orchards in the North of Tunisia against the Mediterranean fruit fly Ceratitis capitata during 2006 and 2007. Results of mass trapping trials in 2006 and 2007 indicated that adult males Medfly captures showed reductions respect to control of 37.62% and 40.2% respectively in mandarin orange variety (Citrus reticulata) orchard compared to 36.48% and 47.29% in Washington navel orange variety (Citrus sinensis) field. Fruit damage assessment showed significant differences between the mass trapping with Tripack and malathion bait-spraying techniques in the reduction of the percentage of fruit punctures. The percentage of punctured fruit at harvest was significantly different between the treated and the control field in 2006 and in 2007 in the mandarin orange orchard. Nevertheless, in the Washington navel orange orchard, the percentage of punctured fruit at harvest was significantly different between the treated and the control field only in 2006. Thus, results obtained from this study showed that the mass trapping technique based on the use of the female-targeted lure Tri-pack could be involved as an appropriate strategy for the control of the Medfly and is as effective as malathion bait spraying treatment without leaving pesticide residues on fruit. (Author) 40 refs.

  4. Evaluating the temporal link between Siberian Traps magmatism and the end-Permian mass extinction (Invited)

    Science.gov (United States)

    Burgess, S. D.; Bowring, S. A.

    2013-12-01

    Interest in Large Igneous Provinces as agents for massive climatic and biological change is steadily increasing, though the temporal constraints on both are seldom precise enough to allow detailed testing of a causal relationship. The end-Permian mass extinction is one of the most biologically important and intensely studied events in Earth history and has been linked to many possible trigger mechanisms, from voluminous volcanism to bolide impact. Proposed kill mechanisms range from acidic and/or anoxic oceans to a cocktail of toxic gases, although the link between trigger and kill mechanisms is unconstrained due to the lack of a high-precision timeline. Critical to assessing the plausibility of different trigger and kill mechanisms is an accurate age model for the biotic crisis and the perturbations to the global carbon cycle and ocean chemistry. Recent work using the EARTHTIME U/Pb tracer solution has refined the timing of the onset and duration of the marine mass extinction event and the earliest Triassic recovery at the GSSP for the Permian-Triassic boundary in Meishan, China. This work constrains the mass extinction duration to less than 100 kyr and provides an accurate and precise time point for the onset of extinction, against which the timing of potential trigger mechanisms may be compared. For more than two decades, eruption and emplacement of the Siberian traps has been implicated as a potential trigger of the end-Permian extinction. In this scenario, magmatism drives the biotic crisis through mobilization of volatiles from the sedimentary rock with which intruding and erupting magmas interact. Massive volatile release is believed to trigger major changes in atmospheric chemistry and temperature, both of which have been proposed as kill mechanisms. Current temporal constrains on the timing and duration of the Siberian magmatism are an order of magnitude less precise than those for the mass extinction event and associated environmental perturbations

  5. A Dual Source Ion Trap Mass Spectrometer for the Mars Organic Molecule Analyzer of ExoMars 2018

    Science.gov (United States)

    Brickerhoff, William B.; vanAmerom, F. H. W.; Danell, R. M.; Arevalo, R.; Atanassova, M.; Hovmand, L.; Mahaffy, P. R.; Cotter, R. J.

    2011-01-01

    We present details on the objectives, requirements, design and operational approach of the core mass spectrometer of the Mars Organic Molecule Analyzer (MOMA) investigation on the 2018 ExoMars mission. The MOMA mass spectrometer enables the investigation to fulfill its objective of analyzing the chemical composition of organic compounds in solid samples obtained from the near surface of Mars. Two methods of ionization are realized, associated with different modes of MOMA operation, in a single compact ion trap mass spectrometer. The stringent mass and power constraints of the mission have led to features such as low voltage and low frequency RF operation [1] and pulse counting detection.

  6. Rapid determination of nicotine in urine by direct thermal desorption ion trap mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Wise, M.B.; Ilgner, R.H.; Guerin, M.R.

    1990-01-01

    The measurement of nicotine and cotinine in physiological fluids (urine, blood serum, and saliva) is widely used as a means of assessing human exposure to environmental tobacco smoke (ETS). Although numerous analytical methods exist for these measurements, they generally involve extensive sample preparation which increases cost and decreases sample throughput. We report the use of thermal desorption directly into an ion trap mass spectrometer (ITMS) for the rapid determination of nicotine and cotinine in urine. A 1{mu}L aliquot of urine is injected into a specially designed inlet and flash vaporized directly into an ITMS through an open-split capillary restrictor interface. Isobutane chemical ionization is used to generate (M+H){sup +} ions of the analytes and collision induced dissociation is used to generate characteristic fragment ions which are used to confirm their identity. Quantification is achieved by integrating the ion current for the characteristic ions and comparing with an external working curve. Detection limits are approximately 50 pg per analyte and the sample turnaround time is approximately 3 minutes without the need for extensive sample preparation. 12 refs., 5 figs.

  7. Characterization of impurities in tylosin using dual liquid chromatography combined with ion trap mass spectrometry.

    Science.gov (United States)

    Chopra, Shruti; Van Schepdael, Ann; Hoogmartens, Jos; Adams, Erwin

    2013-03-15

    Investigation of unknown impurities in a tylosin sample was performed using liquid chromatography coupled to mass spectrometry (LC/MS). Separation was performed according to the recently described LC-UV method of Ashenafi et al. (2011) [14]. This method was reported to have a good selectivity as it was able to separate the four main components of tylosin from the already known and 23 unknown impurities. However, as this method uses a mobile phase with non-volatile constituents, direct characterization of these impurities using LC/MS was not possible. The impurity fractions were therefore first collected and then desalted before sending them to the MS. Identification of the impurities in the tylosin sample was performed with a quadruple ion trap (IT) MS, with an electrospray ionization (ESI) source in the positive ion mode. The structure of the impurities was deduced by comparing their fragmentation pattern with those of the main components of tylosin. As several peaks in the LC-UV method contained multiple compounds, using this method in total 41 new impurities were (partly) characterized.

  8. Simulation of lean NOx trap performance with microkinetic chemistry and without mass transfer.

    Energy Technology Data Exchange (ETDEWEB)

    Larson, Rich; Daw, C. Stuart (Oak Ridge National Laboratory, Knoxville, TN); Pihl, Josh A. (Oak Ridge National Laboratory, Knoxville, TN); Chakravarthy, V. Kalyana (Oak Ridge National Laboratory, Knoxville, TN)

    2011-08-01

    A microkinetic chemical reaction mechanism capable of describing both the storage and regeneration processes in a fully formulated lean NO{sub x} trap (LNT) is presented. The mechanism includes steps occurring on the precious metal, barium oxide (NO{sub x} storage), and cerium oxide (oxygen storage) sites of the catalyst. The complete reaction set is used in conjunction with a transient plug flow reactor code to simulate not only conventional storage/regeneration cycles with a CO/H{sub 2} reductant, but also steady flow temperature sweep experiments that were previously analyzed with just a precious metal mechanism and a steady state code. The results show that NO{sub x} storage is not negligible during some of the temperature ramps, necessitating a re-evaluation of the precious metal kinetic parameters. The parameters for the entire mechanism are inferred by finding the best overall fit to the complete set of experiments. Rigorous thermodynamic consistency is enforced for parallel reaction pathways and with respect to known data for all of the gas phase species involved. It is found that, with a few minor exceptions, all of the basic experimental observations can be reproduced with these purely kinetic simulations, i.e., without including mass-transfer limitations. In addition to accounting for normal cycling behavior, the final mechanism should provide a starting point for the description of further LNT phenomena such as desulfation and the role of alternative reductants.

  9. Measurement of the Wigner Characteristic Function for the Center-of-Mass Motion of Two Trapped Ions

    Institute of Scientific and Technical Information of China (English)

    LINLi-Hua; WANGLing-Zhi; JIANGYun-Kun

    2003-01-01

    We proposed a scheme for the reconstruction of the quantum states for the center-of-mass vibrational mode of two trapped ions. In the scheme the ions are multichromatically excited by three lasers. Then measurement of the difference between probabilities of the ions being both in electronic ground and excited states directly yields the Wigner characteristic function for the center-of-mass vibrational state. The scheme can also be used to prepare entangled coherent states for the center-of-mass and relative vibrational modes.

  10. Measurement of the Wigner Characteristic Function for the Center-of-Mass Motion of Two Trapped Ions

    Institute of Scientific and Technical Information of China (English)

    LIN Li-Hua; WANG Ling-Zhi; JIANG Yun-Kun

    2003-01-01

    We proposed a scheme for the reconstruction of the quantum states for the center-of-mass vibrationalmode of two trapped ions. In the scheme the ions are multichromatically excited by three lasers. Then measurementof the difference between probabilities of the ions being both in electronic ground and excited states directly yields theWigner characteristic function for the center-of-mass vibrational state. The scheme can also be used to prepare entangledcoherent states for the center-of-mass and relative vibrational modes.

  11. Discovery of $^{229}$Rn and the structure of the heaviest Rn and Ra isotopes from Penning-trap mass measurements

    CERN Document Server

    Neidherr, D; Beck, D; Blaum, K; Böhm, Ch; Breitenfeldt, M; Cakirli, R B; Casten, R F; George, S; Herfurth, F; Herlert, A; Kellerbauer, A G; Kowalska, M; Lunney, D; Minaya-Ramirez, E; Naimi, S; Noah, E; Penescu, L; Rosenbusch, M; Schwarz, S; Schweikhard, L; Stora, T

    2009-01-01

    The masses of the neutron-rich radon isotopes $^{223–229}$Rn have been determined for the first time, using the ISOLTRAP setup at CERN ISOLDE. In addition, this experiment marks the first discovery of a new nuclide,$^{229}$Rn, by Penning-trap mass measurement. The new, high-accuracy data allow a fine examination of the mass surface, via the valence-nucleon interaction ${\\delta}$V$_{pn}$. The results reveal intriguing behavior, possibly reflecting either a N=134 subshell closure or an octupolar deformation in this region.

  12. Conception of PIPERADE: A high-capacity Penning-trap mass separator for high isobaric contamination at DESIR

    Energy Technology Data Exchange (ETDEWEB)

    Minaya Ramirez, E., E-mail: minaya@ipno.in2p3.fr [Max-Planck-Institut für Kernphysik, 69117 Heidelberg (Germany); Alfaurt, P.; Aouadi, M.; Ascher, P.; Blank, B. [Centre d’Etudes Nucléaires de Bordeaux-Gradignan (France); Blaum, K. [Max-Planck-Institut für Kernphysik, 69117 Heidelberg (Germany); Cam, J.-F. [Laboratoire de Physique Corpusculaire, Caen (France); Chauveau, P. [Grand Accélérateur National d’Ions Lourds CEA/DSM-CNRS-IN2P3, Caen (France); Daudin, L. [Centre d’Etudes Nucléaires de Bordeaux-Gradignan (France); Delahaye, P. [Grand Accélérateur National d’Ions Lourds CEA/DSM-CNRS-IN2P3, Caen (France); Delalee, F. [Centre d’Etudes Nucléaires de Bordeaux-Gradignan (France); Dupré, P. [Centre de Sciences Nucléaires et de Sciences de la Matière, Orsay (France); El Abbeir, S.; Gerbaux, M.; Grévy, S.; Guérin, H. [Centre d’Etudes Nucléaires de Bordeaux-Gradignan (France); Lunney, D. [Centre de Sciences Nucléaires et de Sciences de la Matière, Orsay (France); Metz, F. [Max-Planck-Institut für Kernphysik, 69117 Heidelberg (Germany); Naimi, S. [Riken, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Perrot, L. [Institut de Physique Nucléaire, Orsay (France); and others

    2016-06-01

    The DESIR (decay, excitation and storage of radioactive ions) facility at GANIL-SPIRAL2 will receive a large variety of exotic nuclei at low energy (up to 60 keV) with high intensities. However, the production methods of radioactive beams are non selective, limiting the purity of the beams of interest. Moreover, the high precision needed for nuclear structure and astrophysics studies using beta decay spectroscopy, laser spectroscopy and trap-based experiments at DESIR requires highly pure samples of exotic nuclei. The aim of the double-Pennig-trap mass separator PIPERADE is to deliver large and very pure samples of exotic nuclei to the different experiments in DESIR. New excitation schemes and a large inner diameter of the first trap will mitigate space charge effects to attempt trapping of up to 10{sup 5} ions per pulse. The purification cycle will be performed in a few milliseconds so that short-lived nuclei can be purified. To extract the nuclides of interest from the large amount of isobaric contaminants, a resolving power of 10{sup 5} is mandatory. Afterwards the ions of interest will be accumulated in the second trap until they constitute a sufficiently pure sample for the measurements. The status of the project is presented.

  13. Proton affinity determinations using the kinetic method in an ion trap mass spectrometer

    Science.gov (United States)

    Nourse, Bobette D.; Graham Cooks, R.

    1991-05-01

    Proton affinities for various compounds have been estimated using a quadrupole ion trap by generating and mass-selecting proton-bound dimers and measuring their dissociation kinetics (A-H+ -B --> AH+ + B and/or BH+ + A). From the relative abundances of the fragment ions ([BH+] and [AH+]), which are related to their relative proton affinities by ln ([AH+]/[BH+]) = [Delta]PA/RT, it is shown that the proton affinities of the alicyclic carboxylic acids decrease in the order: cyclohexane- > cyclopropane- > cyclopentane- > cyclobutanecarboxylic acid. Proton affinity values for these species, measured from their proton-bound dimers with specific ketones, esters and carboxylic acids of known PA, are determined to be 198.3 ± 0.2 kcal mol-1, 198.0 ± 0.2 kcal mol-1, 197.8 ± 0.2 kcal mol-1 and 197.0 ± 0.2 kcal mol-1, respectively. The major contribution to the estimated uncertainties in these values results from the uncertainties in literature proton affinity values for the reference compounds. Proton affinity differences of meta and para deuterated benzoic acid proton-bound to benzoic acid (kH/kD = 1.0 ± 0.1 and 0.9 ± 0.1, respectively), for acetophenone proton-bound to deuterated-acetophenone (C6H5C(O)CD3) (kH/kD = 0.7 ± 0.1) and for 2-pentanone proton-bound to deuterated 2-pentanone (CH3CH2CH2C(O)CH3) (kH/kD = 2.1 ± 0.2). These results, as well as those for the carboxylic acids and benzoic acids given above, are accounted for in terms of stabilizing electronic effects in the protonated molecules.

  14. Linear ion-trap mass spectrometric characterization of human pituitary nitrotyrosine-containing proteins

    Science.gov (United States)

    Zhan, Xianquan; Desiderio, Dominic M.

    2007-01-01

    The nitric oxide-mediated Tyr-nitration of endogenous proteins is associated with several pathological and physiological processes. In order to investigate the presence - and potential roles - of Tyr-nitration in the human pituitary, a large-format two-dimensional gel separation plus a Western blot against a specific anti-3-nitrotyrosine antibody were used to separate and detect nitroproteins from a human pituitary proteome. The nitroproteins were subjected to in-gel trypsin digestion, and high-sensitivity vacuum matrix-assisted laser desorption/ionization (vMALDI) linear ion-trap tandem mass spectrometry was used to analyze the tryptic peptides. Those MS/MS data were used to determine the amino acid sequence and the specific nitration site of each tryptic nitropeptide, and were matched to corresponding proteins with Bioworks TuboSEQUEST software. Compared to our previous study, 16 new nitrotyrosine-immunoreactive positive Western blot spots were found within the area pI 3.0-10 and Mr 10-100 kDa. Four new nitroproteins were discovered: the stanniocalcin 1 precursor--involved in calcium and phosphate metabolism; mitochondrial co-chaperone protein HscB, which might act as a co-chaperone in iron-sulfur cluster assembly in mitochrondria; progestin and adipoQ receptor family member III--a seven-transmembrane receptor; proteasome subunit alpha type 2--involved in an ATP/ubiquitin-dependent non-lysosomal proteolytic pathway. Those data demonstrate that nitric oxide-mediated Tyr-nitration might participate in various biochemical, metabolic, and pathological processes in the human pituitary.

  15. Effect of the trapped mass and its composition on the heat transfer in the compression cycle of a reciprocating engine

    Energy Technology Data Exchange (ETDEWEB)

    Armas, Octavio; Rodriguez, Jose [Departamento de Mecanica Aplicada e Ingenieria de Proyectos, Escuela Tecnica Superior de Ingenieros Industriales, Universidad de Castilla-La Mancha, Ave. Camilo Jose Cela, s/n. Ciudad Real 13071 (Spain); Payri, Francisco; Martin, Jaime [Departamento de Maquinas y Motores Termicos, Escuela Tecnica Superior de Ingenieros Industriales, Universidad Politecnica de Valencia, Avda. de los Naranjos, s/n. 46022 Valencia (Spain); Agudelo, John R. [Grupo Ciencia y Tecnologia del Gas y Uso Racional de la Energia, Universidad de Antioquia, Medellin (Colombia)

    2005-12-01

    The use of the polytropic coefficient calculation during the compression process in the thermodynamic cycle of a reciprocating internal combustion engine is an interesting tool to minimize errors in the synchronization of pressure and volume signals, and to determine heat flux transferred to the cylinder walls. The accuracy of this calculation depends on the instantaneous values for pressure, volume, trapped mass and its composition, as well as on their variations. In this work the effect of the errors in blow-by, trapped mass and its composition have been studied in detail, specially the effect of errors in the composition estimation, owing to the use of exhaust gas recirculation in typical diesel engines. (author)

  16. Infrared atmospheric pressure MALDI ion trap mass spectrometry of frozen samples using a Peltier-cooled sample stage.

    Science.gov (United States)

    Von Seggern, Christopher E; Gardner, Ben D; Cotter, Robert J

    2004-10-01

    Infrared atmospheric pressure matrix-assisted laser desorption/ionization on an ion trap mass spectrometer is used to analyze frozen samples generated using a Peltier-cooled sample stage. This allows for the analysis of samples in water without the addition of matrix, in near-native conditions, and with minimal loss of water due to evaporation. Analysis of frozen samples is extended to study peptides, carbohydrates, and glycolipids.

  17. On-line coupling of solid-phase extraction with mass spectrometry for the analysis of biological samples. II. Determination of clenbuterol in urine using multiple-stage mass spectrometry in an ion-trap mass spectrometer

    NARCIS (Netherlands)

    van Hout, MWJ; Hofland, CM; Niederlander, HAG; de Jong, GJ

    2000-01-01

    Solid-phase extraction (SPE) was coupled to ion-trap mass spectrometry to determine clenbuterol in urine. For SPE a cartridge exchanger was used and, after extraction, the eluate was directly introduced into the mass spectrometer, For two types of cartridges, i.e. C-18 and polydivinylbenzene (PDVB),

  18. Multistage Fragmentation of Ion Trap Mass Spectrometry System and Pseudo-MS3 of Triple Quadrupole Mass Spectrometry Characterize Certain (E)-3-(Dimethylamino)-1-arylprop-2-en-1-ones: A Comparative Study

    OpenAIRE

    Ali S. Abdelhameed; Adnan A. Kadi; Abdel-Aziz, Hatem A.; Angawi, Rihab F.; Mohamed W. Attwa; Al-Rashood, Khalid A.

    2014-01-01

    A new approach was recently introduced to improve the structure elucidation power of tandem mass spectrometry simulating the MS3 of ion trap mass spectrometry system overcoming the different drawbacks of the latter. The fact that collision induced dissociation in the triple quadrupole mass spectrometer system provides richer fragment ions compared to those achieved in the ion trap mass spectrometer system utilizing resonance excitation. Moreover, extracting comprehensive spectra in the ion tr...

  19. Identification of two-dimensional electrophoresis-separated proteins in human hepatoma cell by electrospray ion trap mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    As one of the most important analytical methods in proteome research, mass spectrometry was utilized to identify proteins separated by two-dimensional electrophoresis in the human hepatoma cell line BEL-7404. The protein spots were excised from the gel, followed by in-gel digestion, and the peptide mappings were analyzed by liquid chromatography electrospray ion trap mass spectrometer. Nine proteins were identified via database searching, according to the molecular weights and amino acid sequences of peptides, among which two proteins have not been identified in the other liver-cell database. The sequence coverage was 21%-72%. Furthermore, the relationship between the expressed proteins and the liver carcinoma was discussed.

  20. Mars Organic Molecule Analyzer (MOMA) Mass Spectrometer Flight Model and Future Ion Trap-Based Planetary Instruments

    Science.gov (United States)

    Brinckerhoff, W. B.; van Amerom, F. H. W.; Danell, R.; Pinnick, V. T.; Arevalo, R. D., Jr.; Li, X.; Grubisic, A.; Getty, S.; Hovmand, L.; Mahaffy, P. R.

    2015-12-01

    The Mars Organic Molecule Analyzer (MOMA) investigation on the 2018 ExoMars rover will examine the chemical composition of samples acquired from depths of up to two meters below the martian surface, where organics may be protected from radiative and oxidative degradation. MOMA combines pyrolysis gas chromatography mass spectrometry (GCMS) of bulk powder samples and Mars ambient laser desorption mass spectrometry (LDMS) surface analysis, using a single ion trap MS. This dual source design enables MOMA to detect compounds over a wide range of molecular weights and volatilities. The structure of any detected organics may be further examined using MOMA's tandem mass spectrometry (MS/MS) mode. The flight model (FM) ion trap sensor and electronics have been assembled under the extremely clean and sterile conditions required by ExoMars, and have met or exceeded all performance specifications during initial functional tests. After Mars ambient thermal cycling and calibration, the FM will be delivered as a subsystem of MOMA to rover integration in mid-2016. There MOMA will join complementary rover instruments such as the Raman and MicrOmega spectrometers designed to analyze common drill samples. Following the MOMA design, linear ion trap mass spectrometer (LITMS)-based instruments are under development for future missions. LITMS adds enhanced capabilities such as precision (point-by-point) analysis of drill cores, negative ion detection, a wider mass range, and higher temperature pyrolysis with precision evolved gas analysis, while remaining highly compact and robust. Each of the capabilities of LITMS has been demonstrated on breadboard hardware. The next phase will realize an end-to-end brassboard at flight scale that will meet stringent technology readiness level (TRL) 6 criteria, indicating readiness for development toward missions to Mars, comets, asteroids, outer solar system moons, and beyond.

  1. Determination of vanillin, ethyl vanillin, and coumarin in infant formula by liquid chromatography-quadrupole linear ion trap mass spectrometry.

    Science.gov (United States)

    Shen, Yan; Han, Chao; Liu, Bin; Lin, Zhengfeng; Zhou, Xiujin; Wang, Chengjun; Zhu, Zhenou

    2014-02-01

    A simple, precise, accurate, and validated liquid chromatography-quadrupole linear ion trap mass spectrometry method was developed for the determination of vanillin, ethyl vanillin, and coumarin in infant formula samples. Following ultrasonic extraction with methanol/water (1:1, vol/vol), and clean-up on an HLB solid-phase extraction cartridge (Waters Corp., Milford, MA), samples were separated on a Waters XSelect HSS T3 column (150 × 2.1-mm i.d., 5-μm film thickness; Waters Corp.), with 0.1% formic acid solution-acetonitrile as mobile phase at a flow rate of 0.25 mL/min. Quantification of the target was performed by the internal standard approach, using isotopically labeled compounds for each chemical group, to correct matrix effects. Data acquisition was carried out in multiple reaction monitoring transitions mode, monitoring 2 multiple reaction monitoring transitions to ensure an accurate identification of target compounds in the samples. Additional identification and confirmation of target compounds were performed using the enhanced product ion modus of the linear ion trap. The novel liquid chromatography-quadrupole linear ion trap mass spectrometry platform offers the best sensitivity and specificity for characterization and quantitative determination of vanillin, ethyl vanillin, and coumarin in infant formula and fulfills the quality criteria for routine laboratory application.

  2. CID of singly charged antioxidants applied in lubricants by means of a 3D ion trap and a linear ion trap-Orbitrap mass spectrometer.

    Science.gov (United States)

    Kassler, Alexander; Pittenauer, Ernst; Doerr, Nicole; Allmaier, Guenter

    2011-06-01

    The aim of this study was to investigate the fragmentation behavior induced by low-energy collision-induced dissociation (LE-CID) of four selected antioxidants applied in lubricants, by two different types of ion trap mass spectrometers: a three-dimensional ion trap (3D-IT) and a linear IT (LIT) Orbitrap MS. Two sterically hindered phenols and two aromatic amines were selected as model compounds representing different antioxidant classes and were characterized by positive-ion electrospray ionization (ESI) and LE-CID. Various types of molecular ions (e.g. [M](+•) , [M + H](+) , [M + NH(4) ](+) or [M + Na](+) ) were used as precursor ions generating a significant number of structurally relevant product ions. Furthermore, the phenolic compounds were analyzed by negative-ion ESI. For both IT types applied for fragmentation, the antioxidants exhibited the same unusual LE-CID behavior: (1) they formed stable radical product ions and (2) CC bond cleavages of aliphatic substituents were observed and their respective cleavage sites depended on the precursor ion selected. This fragmentation provided information on the type of structural isomer usually not obtainable for branched aliphatic substituents utilizing LE-CID. Comparing the two instruments, the main benefit of applying the LIT-Orbitrap was direct access to elemental composition of product ions enabling unambiguous interpretation of fragmentation trees not obtainable by the 3D-IT device (e.g. loss of isobaric neutrals). It should be emphasized that the types of product ions formed do not depend on the type of IT analyzer applied. For characterizing degradation products of antioxidants, the LIT-Orbitrap hybrid system, allowing the determination of accurate m/z values for product ions, is the method of choice.

  3. Impenetrable Mass-Imbalanced Particles in One-Dimensional Harmonic Traps

    DEFF Research Database (Denmark)

    Salami Dehkharghani, Amin; Volosniev, A. G.; Zinner, N. T.

    2016-01-01

    . This is particularly important since such problems are generally considered non-integrable and thus the hugely successful Bethe ansatz approach cannot be applied. Here we discuss some initial steps towards this goal by investigating small ensembles of one-dimensional harmonically trapped particles where pairwise...

  4. Earth history. U-Pb geochronology of the Deccan Traps and relation to the end-Cretaceous mass extinction.

    Science.gov (United States)

    Schoene, Blair; Samperton, Kyle M; Eddy, Michael P; Keller, Gerta; Adatte, Thierry; Bowring, Samuel A; Khadri, Syed F R; Gertsch, Brian

    2015-01-09

    The Chicxulub asteroid impact (Mexico) and the eruption of the massive Deccan volcanic province (India) are two proposed causes of the end-Cretaceous mass extinction, which includes the demise of nonavian dinosaurs. Despite widespread acceptance of the impact hypothesis, the lack of a high-resolution eruption timeline for the Deccan basalts has prevented full assessment of their relationship to the mass extinction. Here we apply uranium-lead (U-Pb) zircon geochronology to Deccan rocks and show that the main phase of eruptions initiated ~250,000 years before the Cretaceous-Paleogene boundary and that >1.1 million cubic kilometers of basalt erupted in ~750,000 years. Our results are consistent with the hypothesis that the Deccan Traps contributed to the latest Cretaceous environmental change and biologic turnover that culminated in the marine and terrestrial mass extinctions.

  5. Matrix-assisted laser desorption ion trap mass spectrometry: efficient isolation and effective fragmentation of peptide ions.

    Science.gov (United States)

    Qin, J; Chait, B T

    1996-07-01

    Effective analysis of the sequence of peptides using matrix-assisted laser desorption/ionization (MALDI) tandem ion trap mass spectrometry requires efficient mass isolation and the ability to induce extensive sequence-specific fragmentation. The present paper describes a new excitation scheme, which we term red-shifted off-resonance large-amplitude excitation (RSORLAE), that can deposit higher amounts of internal energy in ions than is feasible with conventional resonant excitation. The new method provides an effective means for inducing fragmentation of MALDI-produced peptide ions with m/z values up to 3500. Prior to excitation, it is necessary to isolate ions of interest with high efficiency. We demonstrate that isolation efficiencies of > 95% can be achieved by careful design of the rf scan functions used during ion isolation. In particular, sudden transitions in the amplitude of the rf field (from low to high amplitudes) must be avoided. The combined improvements in the efficiency for ion isolation and the efficacy of ion activation make MALDI tandem ion trap mass spectrometry a practical tool for the characterization of proteins with high sensitivity.

  6. Decomposition of cyclohexane ion induced by intense femtosecond laser fields by ion-trap time-of-flight mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Yamazaki, Takao; Watanabe, Yusuke; Kanya, Reika [Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Yamanouchi, Kaoru, E-mail: kaoru@chem.s.u-tokyo.ac.jp [Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); NANOQUINE, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2016-01-14

    Decomposition of cyclohexane cations induced by intense femtosecond laser fields at the wavelength of 800 nm is investigated by ion-trap time-of-flight mass spectrometry in which cyclohexane cations C{sub 6}H{sub 12}{sup +} stored in an ion trap are irradiated with intense femtosecond laser pulses and the generated fragment ions are recorded by time-of-flight mass spectrometry. The various fragment ion species, C{sub 5}H{sub n}{sup +} (n = 7, 9), C{sub 4}H{sub n}{sup +} (n = 5–8), C{sub 3}H{sub n}{sup +} (n = 3–7), C{sub 2}H{sub n}{sup +} (n = 2–6), and CH{sub 3}{sup +}, identified in the mass spectra show that decomposition of C{sub 6}H{sub 12}{sup +} proceeds efficiently by the photo-irradiation. From the laser intensity dependences of the yields of the fragment ion species, the numbers of photons required for producing the respective fragment ions are estimated.

  7. Suppression of Rice Stem Borer, Chilo suppressalis by Mass Trapping Using Synthetic Sex Pheromone in Paddy Field

    Institute of Scientific and Technical Information of China (English)

    SU Jian-wei; XUAN Wei-jian; SHENG Cheng-fa; GE Feng

    2003-01-01

    Suppressing effects of mass trapping using synthetic sex pheromone with main active ingredients of Z-11-hexadecenal, Z-13-octadecenal and Z-9-hexadecenal on the rice stem borer, Chilo suppressalis were investigated during the flight periods of the overwintering and 1st generation in the paddy area of 60 ha in 1999. Population density of C. suppressalis in the pheromone-treated fields was lower than that in control. The egg masses decreased by 74.39% and population size of adult males of the 1st generation decreased by 61.64% in the treated fields as compared to control. Meanwhile, the damage by C.suppressalis larvae was significantly lower in the treated fields than control (t-test, P=0.05). Percentages of brownish leaf sheath, dead heart, and white head in the treated fields were decreased by 70.90%, 57.01% and 44.30%, respectively in contrast to control. The present study demonstrated that mass trapping to C. suppressalis using synthetic sex pheromone shows great potential as an alternative measure in an environment-friendly pest management and at the same challenging the insecticide use that has some environment impacts.

  8. Extending and refining the mass surface around $^{208}$Pb by high-precision Penning-trap mass spectrometry with ISOLTRAP

    CERN Multimedia

    Herfurth, F; Stora, T; Blaum, K; Beck, D; Kowalska, M; Schwarz, S; Stanja, J; Herlert, A J; Yamaguchi, T

    We propose high-precision mass spectrometry of nuclides around the doubly magic $^{208}$Pb. On the neutron-rich side, we aim to extend the knowledge of Fr, At, Hg, and Au masses to study the robustness of the N = 126 shell closure and to provide mass data necessary for modeling the rapid-neutron-capture process. On the proton-rich side, we aim at high-resolution mass spectrometry of selected Au, At, and Fr isotopes to verify the predicted existence of very low-lying isomeric states. The proposal will make use of newly-available laser-ionization schemes for Au and At. Finally, the recently implemented multi-reflection time-of-flight mass separator for auxiliary isobaric purification now allows measurements which were not feasible before.

  9. Identification of phosphorylation sites of proteins by high performance liquid chromatography-electrospray ionization-quadrupole ion trap mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The phosphorylation sites of two phosphorylated proteins, bovine b-casein and myelin basic protein (MBP), were identified by high performance liquid chromatography-electrospray ionization-quadrupole ion trap mass spectrometry (HPLC-ESI-QITMS). The tryptic digest of each protein was separated by HPLC, the molecular weight of each peptide was determined by ESI-QITMS on line, and MS/MS spectrum of each peptide was simultaneously obtained by the combination of collision-induced desorption (CID) technique and tandem mass spectrometry (MS/MS) of QITMS. The phosphorylated peptide was identified by looking into whether the difference between the observed and predicted molecular weights of a peptide is 80 u or its integral multiple. Then the phosphorylation site was identified through manual interpretation of the MS/MS spectrum of the phosphorylated peptide or automatic SEQUEST data base-searching.

  10. Identification of phosphorylation sites of proteins by high performance liquid chromatography-electrospray ionization-quadrupole ion trap mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    车发云; 邵晓霞; 夏其昌

    2000-01-01

    The phosphorylation sites of two phosphorylated proteins, bovine β-casein and myelin basic protein (MBP), were identified by high performance liquid chromatography-electrospray ionization-quadrupole ion trap mass spectrometry (HPLC-ESI-QITMS). The tryptic digest of each protein was separated by HPLC, the molecular weight of each peptide was determined by ESI-QITMS on line, and MS/MS spectrum of each peptide was simultaneously obtained by the combination of collision-induced desorption (CID) technique and tandem mass spectrometry (MS/MS) of QITMS. The phosphorylated peptide was identified by looking into whether the difference between the observed and predicted molecular weights of a peptide is 80 u or its integral multiple. Then the phosphorylation site was identified through manual interpretation of the MS/MS spectrum of the phosphorylated peptide or automatic SEQUEST data base-searching.

  11. Quantitative analysis of cytokinins in plants by high performance liquid chromatography: electronspray ionization ion trap mass spectrometry.

    Science.gov (United States)

    Chen, Weiqi; Gai, Ying; Liu, Shichang; Wang, Renxiao; Jiang, Xiangning

    2010-10-01

    The present paper introduces a highly sensitive and selective method for simultaneous quantification of 12 cytokinins (free form and their conjugates). The method includes a protocol of extraction with methanol/water/formic acid (15/4/1, v/v/v) to the micro-scale samples, pre-purification with solid phase extraction (SPE) cartridges of the extracts, separation with a high performance liquid chromatography (HPLC) and detection by an electrospray ionization ion trap mass spectrometry (ESI-Ion trap-MS) system in a consecutive ion monitoring (CRM) mode at the three stage fragmentation of mass spectrometry (MS(3) ). The lowest detection level of the cytokinins of the method reaches 0.1-2.0 pg with a very wide range of linear regression from 1-512 pg, at the coefficient factors of 0.98-0.99. The feasibility of this method has been proven in the application of the method to the analysis of the trace-amount contents of cytokinins in the micro-scale samples of various types of plant materials, such as aerial parts of rice and poplar leaves etc. 12 endogenous cytokinins had been identified and quantified in the plant tissues, with an acceptable relatively higher recovery rate from 40% to 70%.

  12. An aircraft-borne chemical ionization – ion trap mass spectrometer (CI-ITMS for fast PAN and PPN measurements

    Directory of Open Access Journals (Sweden)

    H. Schlager

    2011-02-01

    Full Text Available An airborne chemical ionization ion trap mass spectrometer instrument (CI-ITMS has been developed for tropospheric and stratospheric fast in-situ measurements of PAN (peroxyacetyl nitrate and PPN (peroxypropionyl nitrate. The first scientific deployment of the FASTPEX instrument (FASTPEX = Fast Measurement of Peroxyacyl nitrates took place in the Arctic during 18 missions aboard the DLR research aircraft Falcon, within the framework of the POLARCAT-GRACE campaign in the summer of 2008. The FASTPEX instrument is described and characteristic properties of the employed ion trap mass spectrometer are discussed. Atmospheric data obtained at altitudes of up to ~12 km are presented, from the boundary layer to the lowermost stratosphere. Data were sampled with a time resolution of 2 s and a 2σ detection limit of 25 pmol mol−1. An isotopically labelled standard was used for a permanent on-line calibration. For this reason the accuracy of the PAN measurements is better than ±10% for mixing ratios greater than 200 pmol mol−1. PAN mixing ratios in the summer Arctic troposphere were in the order of a few hundred pmol mol−1 and generally correlated well with CO. In the Arctic boundary layer and lowermost stratosphere smaller PAN mixing ratios were observed due to a combination of missing local sources of PAN precursor gases and efficient removal processes (thermolysis/photolysis. PPN, the second most abundant PAN homologue, was measured simultaneously. Observed PPN/PAN ratios range between ~0.03 and 0.3.

  13. Quantitative Analysis of Cytokinins in Plants by High Performance Liquid Chromatography: Electronspray Ionization Ion Trap Mass Spectrometry

    Institute of Scientific and Technical Information of China (English)

    Weiqi Chen; Ying Gai; Shichang Liu; Renxiao Wang; Xiangning Jiang

    2010-01-01

    The present paper introduces a highly sensitive and selective method for simultaneous quantification of 12 cytokinins(free form and their conjugates).The method includes a protocol of extraction with methanol/water/formic acid(1514/1,v/v/v)to the micro-scale samples,pre-purification with solid phase extraction(SPE)cartridges of the extracts,separation with a high performance liquid chromatography(HPLC)and detection by an electrospray ionization ion trap mass spectrometry(ESI-Ion trap-MS)system in a consecutive ion monitoring(CRM)mode at the three stage fragmentation of mass spectrometry(MS3).The lowest detection level of the cytokinins of the method reaches 0.1-2.0 pg with a very wide range of linear regression from 1-512 pg,at the coefficient factors of 0.98-0.99.The feasibility of this method has been proven in the application of the method to the analysis of the trace-amount contents of cytokinins in the micro-scale samples of various types of plant materials,such as aerial parts of rice and poplar leaves etc.12 endogenous cytokinins had been identified and quantified in the plant tissues,with an acceptable relatively higher recovery rate from 40% to 70%.

  14. 基于气相色谱-离子阱法的纺织品及皮革中的富马酸二甲酯检测%Determination of dimethyl fumarate in textiles and leather products by Gas Chromatography-Ion Trap mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    孙忠松; 王境堂; 高永刚; 蔡发

    2010-01-01

    为了解决样品基体复杂,干扰测定的难题,建立了一种基于气相色谱-离子阱二级质谱(GC-MS/MS)检测纺织品及皮革制品中富马酸二甲酯的方法.样品中富马酸二甲酯经乙腈提取,PSA/SAX小柱净化,GC-MS/MS进行定量和定性分析.该法采用化学源电离,甲醇作为反应气,并对前处理过程所用提取溶剂,净化过程,CID电压进行了优化,大大提高灵敏度和选择性.该方法在0.05~10.0μg/mL浓度范围内呈线性关系,相关系数为0.999 8,仪器定量检出限LOQ为0.05 mg/kg,外标法定量.在50,500,1 000μg/kg 3个水平的相对标准偏差为3.52%~6.12%,回收率为84.0%~99.5%.结果表明,相对于GC、GC-MS方法,GC-MS/MS分析时间短,无杂质峰干扰,灵敏度高,可以满足纺织品及皮革制品中检测大批量筛选要求.

  15. Positive ion chemistry in the exhaust plumes of an air craft jet engine and a burner: investigations with a quadrupole ion trap mass spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Kiendler, A.; Aberle, S.; Arnold, F. [Max Planck Institute for Nuclear Physics, Heidelberg (Germany). Atmospheric Physics Div.

    2000-07-01

    Using a quadrupole ion trap mass spectrometer detailed composition analyses were made of positive ions in the exhaust of an aircraft jet engine and of a jet fuel burner. For both scenarios complex organic ions with large mass numbers were most abundant. By employing the MS{sup 2}-mode of the quadrupole ion trap mass spectrometer, mass selected trapped ions were intendently broken up and characteristic fragment ions were observed. The latter indicate that the parent ions contain hydrogen, carbon and oxygen which is indicative of oxygenated hydrocarbons. This contrasts recent composition measurements of negative ions in aircraft jet engine exhaust made by our group which revealed that negative ions contain the inorganic acid H{sub 2}SO{sub 4}. Our present measurements support the view that positive ions in aircraft jet engine exhaust contain preferably organic molecules. (author)

  16. Multistage fragmentation of ion trap mass spectrometry system and pseudo-MS3 of triple quadrupole mass spectrometry characterize certain (E)-3-(dimethylamino)-1-arylprop-2-en-1-ones: a comparative study.

    Science.gov (United States)

    Abdelhameed, Ali S; Kadi, Adnan A; Abdel-Aziz, Hatem A; Angawi, Rihab F; Attwa, Mohamed W; Al-Rashood, Khalid A

    2014-01-01

    A new approach was recently introduced to improve the structure elucidation power of tandem mass spectrometry simulating the MS(3) of ion trap mass spectrometry system overcoming the different drawbacks of the latter. The fact that collision induced dissociation in the triple quadrupole mass spectrometer system provides richer fragment ions compared to those achieved in the ion trap mass spectrometer system utilizing resonance excitation. Moreover, extracting comprehensive spectra in the ion trap needs multistage fragmentation, whereas similar fragment ions may be acquired from one stage product ion scan using the triple quadrupole mass spectrometer. The new strategy was proven to enhance the qualitative performance of tandem mass spectrometry for structural elucidation of different chemical entities. In the current study we are endeavoring to prove our hypothesis of the efficiency of the new pseudo-MS(3) technique via its comparison with the MS(3) mode of ion trap mass spectrometry system. Ten pharmacologically and synthetically important (E)-3-(dimethylamino)-1-arylprop-2-en-1-ones (enaminones 4a-j) were chosen as model compounds for this study. This strategy permitted rigorous identification of all fragment ions using triple quadrupole mass spectrometer with sufficient specificity. It can be used to elucidate structures of different unknown components. The data presented in this paper provide clear evidence that our new pseudo-MS(3) may simulate the MS(3) of ion trap spectrometry system.

  17. Multistage Fragmentation of Ion Trap Mass Spectrometry System and Pseudo-MS3 of Triple Quadrupole Mass Spectrometry Characterize Certain (E-3-(Dimethylamino-1-arylprop-2-en-1-ones: A Comparative Study

    Directory of Open Access Journals (Sweden)

    Ali S. Abdelhameed

    2014-01-01

    Full Text Available A new approach was recently introduced to improve the structure elucidation power of tandem mass spectrometry simulating the MS3 of ion trap mass spectrometry system overcoming the different drawbacks of the latter. The fact that collision induced dissociation in the triple quadrupole mass spectrometer system provides richer fragment ions compared to those achieved in the ion trap mass spectrometer system utilizing resonance excitation. Moreover, extracting comprehensive spectra in the ion trap needs multistage fragmentation, whereas similar fragment ions may be acquired from one stage product ion scan using the triple quadrupole mass spectrometer. The new strategy was proven to enhance the qualitative performance of tandem mass spectrometry for structural elucidation of different chemical entities. In the current study we are endeavoring to prove our hypothesis of the efficiency of the new pseudo-MS3 technique via its comparison with the MS3 mode of ion trap mass spectrometry system. Ten pharmacologically and synthetically important (E-3-(dimethylamino-1-arylprop-2-en-1-ones (enaminones 4a–j were chosen as model compounds for this study. This strategy permitted rigorous identification of all fragment ions using triple quadrupole mass spectrometer with sufficient specificity. It can be used to elucidate structures of different unknown components. The data presented in this paper provide clear evidence that our new pseudo-MS3 may simulate the MS3 of ion trap spectrometry system.

  18. Development of a new method for the enantiomer specific determination of HBCD using an ion trap mass spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Gomara, Belen [Department of Instrumental Analysis and Environmental Chemistry, Institute of General Organic Chemistry (CSIC), Juan de la Cierva 3, 28006 Madrid (Spain)], E-mail: bgomara@iqog.csic.es; Lebron-Aguilar, Rosa [Institute of Physical Chemistry ' Rocasolano' (CSIC), Serrano 119, 28006 Madrid (Spain); Quintanilla-Lopez, Jesus Eduardo [Institute of Physical Chemistry ' Rocasolano' (CSIC), Serrano 119, 28006 Madrid (Spain); Departamento de Ingenieria Quimica Industrial y del Medio Ambiente, ETSI Industriales (UPM), Jose Gutierrez Abascal 2, 28006 Madrid (Spain); Gonzalez, Maria Jose [Department of Instrumental Analysis and Environmental Chemistry, Institute of General Organic Chemistry (CSIC), Juan de la Cierva 3, 28006 Madrid (Spain)

    2007-12-12

    An alternative method for the enantiomer specific determination of hexabromocyclododecanes (HBCD) by LC-ESI-MS/MS using an ion trap analyser is proposed. The method is based on the formation of a chlorine adduct (m/z 676.6) of the ({+-}){alpha}-, ({+-}){beta}-, and ({+-}){gamma}-HBCD enantiomers and their further fragmentation into their stable quasi-molecular ion (m/z 640.6). In this way, problems related to the ion trap low mass cutoff and variable amounts of other adduct peaks in the samples are solved. Parameters affecting separation, ionisation and MS/MS detection were studied. Method performance was also evaluated: calibration curves were found linear from 20 to 400 pg {mu}L{sup -1} for each enantiomer; detection limits ranged between 1.5 and 4.3 pg {mu}L{sup -1}; repeatability and reproducibility, expressed as relative standard deviation, were lower than 6% and 13%, respectively. The application to different types of spiked samples (pork meat, lean fish, and butter) pointed out the occurrence of matrix effects that could be solved by using labelled standards.

  19. Resonance activation and collision-induced-dissociation of ions using rectangular wave dipolar potentials in a digital ion trap mass spectrometer.

    Science.gov (United States)

    Xu, Fuxing; Wang, Liang; Dai, Xinhua; Fang, Xiang; Ding, Chuan-Fan

    2014-04-01

    Collision-induced dissociation (CID) of ions by resonance activation in a quadrupole ion trap is usually accomplished by resonance exciting the ions to higher kinetic energy, whereby the high kinetic energy ions collide with a bath gas, such as helium or argon, inside the trap and dissociate to fragments. A new ion activation method using a well-defined rectangular wave dipolar potential formed by dividing down the trapping rectangular waveform is developed and examined herein. The mass-selected parent ions are resonance excited to high kinetic energies by simply changing the frequency of the rectangular wave dipolar potential and dissociation proceeds. A relationship between the ion mass and the activation waveform frequency is also identified and described. This highly efficient (CID) procedure can be realized by simply changing the waveform frequency of the dipolar potential, which could certainly simplify tandem mass spectrometry analysis methods.

  20. Surface-activated chemical ionization ion trap mass spectrometry in the analysis of amphetamines in diluted urine samples.

    Science.gov (United States)

    Cristoni, Simone; Bernardi, Luigi Rossi; Gerthoux, Piermario; Gonella, Elisabetta; Mocarelli, Paolo

    2004-01-01

    A new ionization method, named surface-activated chemical ionization (SACI), was employed for the analysis of five amphetamines (3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyethylamphetamine (MDE), amphetamine and methamphetamine) by ion trap mass spectrometry. The results so obtained have been compared with those achieved by using atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI) using the same instrument, clearly showing that SACI is the most sensitive of the three. The limit of detection and linearity range for SACI were compared with those obtained using APCI and ESI, showing that the new SACI approach provides the best results for both criteria. SACI was used to analyze MDA, MDMA MDE, amphetamine and methamphetamine in four urine samples, and the quantitation results are compared with those achieved using ESI.

  1. The detection of piroxicam, tenoxicam and their metabolites in equine urine by electrospray ionisation ion trap mass spectrometry.

    Science.gov (United States)

    McKinney, Andrew R; Suann, Craig J; Stenhouse, Allen M

    2004-01-01

    An investigation has been conducted into the metabolism and urinary excretion of orally administered piroxicam and tenoxicam in the horse. The major component detected in urine after the administration of piroxicam was 5'-hydroxypiroxicam, which was detectable up to 24 h post-administration. Unchanged piroxicam was present only as a minor component. In contrast, unchanged tenoxicam was the major component observed after the administration of tenoxicam, being detectable for 72 h post-administration, while 5'-hydroxytenoxicam was a minor component. Phase II beta-glucuronide conjugation in each case was found to be negligible. The ion trap mass spectral characteristics of piroxicam, tenoxicam, 5'-hydroxypiroxicam and 5'-hydroxytenoxicam under electrospray ionisation conditions were examined in some detail.

  2. Quantitative analysis of [Dmt(1)]DALDA in ovine plasma by capillary liquid chromatography-nanospray ion-trap mass spectrometry.

    Science.gov (United States)

    Wan, Haibao; Umstot, Edward S; Szeto, Hazel H; Schiller, Peter W; Desiderio, Dominic M

    2004-04-15

    The synthetic opioid peptide analog Dmt-D-Arg-Phe-Lys-NH(2) ([Dmt(1)]DALDA; [Dmt= 2',6'-dimethyltyrosine) is a highly potent and selective mu opioid-receptor agonist. A very sensitive and robust capillary liquid chromatography/nanospray ion-trap (IT) mass spectrometry method has been developed to quantify [Dmt(1)]DALDA in ovine plasma, using deuterated [Dmt(1)]DALDA as the internal standard. The standard MS/MS spectra of d(0)- and d(5)-[Dmt(1)]DALDA were obtained, and the collision energy was experimentally optimized to 25%. The product ion [ M + 2H-NH(3)](2+) (m/z 312.2) was used to identify and to quantify the synthetic opioid peptide analog in ovine plasma samples. The MS/MS detection sensitivity for [Dmt(1)]DALDA was 625 amol. A calibration curve was constructed, and quantitative analysis was performed on a series of ovine plasma samples.

  3. Advanced stored waveform inverse Fourier transform technique for a matrix-assisted laser desorption/ionization quadrupole ion trap mass spectrometer.

    Science.gov (United States)

    Doroshenko, V M; Cotter, R J

    1996-01-01

    The stored waveform inverse Fourier transform (SWIFT) technique is used for broadband excitation of ions in an ion-trap mass spectrometer to perform mass-selective accumulation, isolation, and fragmentation of peptide ions formed by matrix-assisted laser desorption/ionization. Unit mass resolution is achieved for isolation of ions in the range of m/z up to 1300 using a two-step isolation technique with stretched-in-time narrow band SWIFT pulses at the second stage. The effect of 'stretched-in-time' waveforms is similar to that observed previously for mass-scan-rate reduction. The asymmetry phenomenon resulting from the stretched ion-trap electrode geometry is observed during application of normal and time-reversed waveforms and is similar to the asymmetry effects observed for forward and reverse mass scans in the resonance ejection mode. Mass-selective accumulation of ions from multiple laser shots was accomplished using a method described earlier that involves increasing the trapping voltage during ion introduction for more efficient trapping of ions.

  4. Quantum-State Engineering of Multiple Trapped Ions for Center-of-Mass Mode

    Institute of Scientific and Technical Information of China (English)

    ZENG Hao-Sheng; KUANG Le-Man; ZHU Xi-Wen; GAO Ke-Lin

    2001-01-01

    We propose a scheme to generate a superposition of coherent states with arbitrary coeffcients on a line in phase space for the center-of-mass vibrational mode of N ions by means of isolating all other spectator vibrational modes from the center-of-mass mode. It can be viewed as the generalization of previous methods for preparing motional states of one ion. For a large number of ions, only one cyclic operation enables one to generate such a superposition of many coherent states.``

  5. Liquid chromatography coupled with time-of-flight and ion trap mass spectrometry for qualitative analysis of herbal medicines

    Institute of Scientific and Technical Information of China (English)

    Xiao-Fei Chen; Hai-Tang Wu; Guang-Guo Tan; Zhen-Yu Zhu; Yi-Feng Chai

    2011-01-01

    With the expansion of herbal medicine (HM) market, the issue on how to apply up-to- date analytical tools on qualitative analysis of HMs to assure their quality, safety and efficacy has been arousing great attention. Due to its inherent characteristics of accurate mass measurements and multiple stages analysis, the integrated strategy of liquid chromatography (LC) coupled with time-of-flight mass spectrometry (TOF-MS) and ion trap mass spectrometry (IT-MS) is well-suited to be performed as qualitative analysis tool in this field. The purpose of this review is to provide an overview on the potential of this integrated strategy, including the review of general features of LC-IT-MS and LC-TOF-MS, the advantages of their combination, the common procedures for structure elucidation, the potential of LC-hybrid-IT-TOF/MS and also the summary and discussion of the applications of the integrated strategy for HM qualitative analysis (2006-2011). The advantages and future developments of LC coupled with IT and TOF-MS are highlighted.

  6. Analysis of lightweight gases by quadrupole ion trap mass spectrometry for the safety of the American Space Shuttle program

    Science.gov (United States)

    Ottens, Andrew Keith

    The quadrupole ion trap mass spectrometer (QITMS) was patented nearly 50 years ago, when it was proposed for trace analysis of lightweight gas mixtures. Though a commercial success, QITMS has been used with analytes of ever-increasing size. We evaluated QITMS for quantifying lightweight gas mixtures with the performance compared to other mass analyzer technologies. The National Aeronautics and Space Administration (NASA) uses mass spectrometers to monitor the amount of hydrogen, helium, oxygen, and argon in the nitrogen-purged Space Shuttle. The explosive hazard of the cryogenic hydrogen and oxygen used to propel the Space Shuttle makes leak detection imperative. The two present-day leak detectors are remotely located because of their large size and sensitivity to vibration. Analysis is delayed by up to 45 s, and only two samples can be monitored simultaneously. In 2000, NASA initiated the Advanced Hazardous Gas Detection project to develop a compact, rugged, and fast mass spectrometer to be placed in multiple locations next to the Space Shuttle to provide real-time analysis with increased redundancy. The QITMS instrumentation was modified specifically for this application. The RF drive frequency was increased to 2.5 MHz to adequately trap lightweight hydrogen and helium ions. Internal ionization was preferred for use without a collision gas, along with an open source configuration that provided rapid sample replacement. The modern electronics incorporated were controlled by customized software. Analytes were found to react rapidly with abundant background gases. The QITMS operating conditions were optimized to minimize negative effects of ion-molecule reactions while maximizing analytical performance. A custom segmented scan function was developed with a total scan time of 14 ms, averaging 70 scans per data point at the required 1 Hz update rate. The QITMS met requirements for detection limits, accuracy, precision, response time, and recovery time. The linear

  7. Determining the site of spin trapping of the equine myoglobin radical by combined use of EPR, electrophoretic purification, and mass spectrometry.

    Science.gov (United States)

    Harris, Michael N; Burchiel, Scott W; Winyard, Paul G; Engen, John R; Mobarak, Charlotte D; Timmins, Graham S

    2002-12-01

    Although myoglobin protein radicals are thought important intermediates in peroxide-induced toxicity, the site of spin trapping of this radical in equine myoglobin using the trap 3,5-dibromo-4-nitrosobenzene sulfonate (DBNBS) is unclear. We have combined EPR, electrophoretic adduct purification, and mass spectrometry approaches to unambiguously determine the site of trapping to be Tyr-103 and suggest that reports of trapping at Trp-7 or Trp-14 may be due to nonradical addition to proteolytically derived Trp-containing peptides with DBNBS. The technique developed here of combining electrophoretic separation of DBNBS adducts with MS of resultant peptides will also allow proteomic-like approaches to determining identities and sites of radical formation and translocation on complex mixtures of proteins.

  8. Precision mass measurements for studies of nucleosynthesis via the rapid neutron-capture process. Penning-trap mass measurements of neutron-rich cadmium and caesium isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Atanasov, Dinko

    2016-07-06

    Although the theory for the rapid neutron-capture process (r-process) was developed more than 55 years ago, the astrophysical site is still under a debate. Theoretical studies predict that the r-process path proceeds through very neutron-rich nuclei with very asymmetric proton-to-neutron ratios. Knowledge about the properties of neutron-rich isotopes found in similar regions of the nuclear chart and furthermore suitable for r-process studies is still little or even not existing. The basic nuclear properties such as binding energies, half-lives, neutron-induced or neutron-capture reaction cross-sections, play an important role in theoretical simulations and can vary or even drastically alternate results of these studies. Therefore, a considerable effort was put forward to access neutron-rich isotopes at radioactive ion-beam facilities like ISOLDE at CERN. The goal of this PhD thesis is to describe the experimental work done for the precision mass measurements of neutron-rich cadmium ({sup 129-131}Cd) and caesium ({sup 132,146-148}Cs) isotopes. Measurements were done at the on-line radioactive ion-beam facility ISOLDE by using the four-trap mass spectrometer ISOLTRAP. The cadmium isotopes are key nuclides for the synthesis of stable isotopes around the mass peak A = 130 in the Solar System abundance.

  9. Leisure Traveling for 21st Century Americans: Mass Tourism as a Cultural Trap

    Directory of Open Access Journals (Sweden)

    Aniculăese Ovidiu

    2014-01-01

    Full Text Available The majority of mass men in the American environment exhibit predictable and similar patterns of behavior as tourists. Pre-Industrial Revolution modes of traveling as liberation and exploration are now thwarted by the leveling effect of globalization and the illusion of information fueled by the all-pervasive mass media. Claims about the role of routine or the quest for authenticity are challenged as genuine motivations for mass tourism. Both the American culture and travel destinations in developing countries have authentic content that is largely ignored in favor of sensationalism and cliché. Excessive regimentation in the US creates the acute need for transcending to which popular culture finds accessible solutions through tourism: an experience of concentrated yet vague exoticism which feels liberating without yielding exploration. Travel destinations are shaped to American standards of material comfort and even adopt western popular culture icons in an effort to supply accessible familiar experiences of western entertainment. Various kinds of difficulty that once stimulated travelers are now relieved by travel agencies, rendering the experience of traveling less personal and more like TV entertainment. Old notions of space, time and reality itself are blurred in favor of a hyper-reality where fiction dominates.

  10. Thermally Accelerated Oxidative Degradation of Quercetin Using Continuous Flow Kinetic Electrospray-Ion Trap-Time of Flight Mass Spectrometry

    Science.gov (United States)

    Barnes, Jeremy S.; Foss, Frank W.; Schug, Kevin A.

    2013-10-01

    Thermally accelerated oxidative degradation of aqueous quercetin at pH 5.9 and 7.4 was kinetically measured using an in-house built online continuous flow device made of concentric capillary tubes, modified to fit to the inlet of an electrospray ionization-ion trap-time-of-flight-mass spectrometer (ESI-IT-TOF-MS). Time-resolved mass spectral measurements ranging from 2 to 21 min were performed in the negative mode to track intermediate degradation products and to evaluate the degradation rate of the deprotonated quercetin ion, [Q-H]-. Upon heating solutions in the presence of dissolved oxygen, degradation of [Q-H]- was observed and was accelerated by an increase in pH and temperature. Regardless of the condition, the same degradation pathways were observed. Degradation mechanisms and structures were determined using higher order tandem mass spectrometry (up to MS3) and high mass accuracy. The observed degradation mechanisms included oxidation, hydroxylation, and ring-cleavage by nucleophilic attack. A chalcan-trione structure formed by C-ring opening after hydroxylation at C2 was believed to be a precursor for other degradation products, formed by hydroxylation at the C2, C3, and C4 carbons from attack by nucleophilic species. This resulted in A-type and B-type ions after cross-ring cleavage of the C-ring. Based on time of appearance and signal intensity, nucleophilic attack at C3 was the preferred degradation pathway, which generated 2,4,6-trihydroxymandelate and 2,4,6-trihydroxyphenylglyoxylate ions. Overall, 23 quercetin-related ions were observed.

  11. Correlation between y-Type Ions Observed in Ion Trap and Triple Quadrupole Mass Spectrometers

    OpenAIRE

    Sherwood, Carly A.; Eastham, Ashley; Lee, Lik Wee; Risler, Jenni; Vitek, Olga; Martin, Daniel B.

    2009-01-01

    Multiple reaction monitoring mass spectrometry (MRM-MS) is a technique for high-sensitivity targeted analysis. In proteomics, MRM-MS can be used to monitor and quantify a peptide based on the production of expected fragment peaks from the selected peptide precursor ion. The choice of which fragment ions to monitor in order to achieve maximum sensitivity in MRM-MS can potentially be guided by existing MS/MS spectra. However, because the majority of discovery experiments are performed on ion tr...

  12. Food contaminant analysis at ultra-high mass resolution: application of hybrid linear ion trap - orbitrap mass spectrometry for the determination of the polyether toxins, azaspiracids, in shellfish.

    LENUS (Irish Health Repository)

    2010-10-30

    The biotoxins, azaspiracids (AZAs), from marine phytoplankton accumulate in shellfish and affect human health by causing severe gastrointestinal disturbance, diarrhea, nausea and vomiting. Specific and sensitive methods have been developed and validated for the determination of the most commonly occurring azaspiracid analogs. An LTQ Orbitrap mass spectrometer is a hybrid instrument that combines linear ion trap (LIT) mass spectrometry (MS) with high-resolution Fourier transform (FT) MS and this was exploited to perform simultaneous ultra-high-resolution full-scan MS analysis and collision-induced dissociation (CID) tandem mass spectrometry (MS\\/MS). Using the highest mass resolution setting (100,000 FWHM) in full-scan mode, the methodology was validated for the determination of six AZAs in mussel (Mytilus galloprovincialis) tissue extracts. Ultra-high mass resolution, together with a narrow mass tolerance window of ±2 mDa, dramatically improved detection sensitivity. In addition to employing chromatographic resolution to distinguish between the isomeric azaspiracid analogs, AZA1\\/AZA6 and AZA4\\/AZA5, higher energy collisionally induced dissociation (HCD) fragmentation on selected precursor ions were performed in parallel with full-scan FTMS. Using HCD MS\\/MS, most precursor and product ion masses were determined within 1 ppm of the theoretical m\\/z values throughout the mass spectral range and this enhanced the reliability of analyte identity.For the analysis of mussels (M. galloprovincialis), the method limit of quantitation (LOQ) was 0.010 µg\\/g using full-scan FTMS and this was comparable with the LOQ (0.007 µg\\/g) using CID MS\\/MS. The repeatability data were; intra-day RSD% (1.8-4.4%; n = 6) and inter-day RSD% (4.7-8.6%; n = 3). Application of these methods to the analysis of mussels (M. edulis) that were naturally contaminated with azaspiracids, using high-resolution full-scan Orbitrap MS and low-resolution CID MS\\/MS, produced

  13. Quantitation of isobaric phosphatidylcholine species in human plasma using a hybrid quadrupole linear ion-trap mass spectrometer.

    Science.gov (United States)

    Zacek, Petr; Bukowski, Michael; Rosenberger, Thad A; Picklo, Matthew

    2016-12-01

    Phosphatidylcholine (PC) species in human plasma are used as biomarkers of disease. PC biomarkers are often limited by the inability to separate isobaric PCs. In this work, we developed a targeted shotgun approach for analysis of isobaric and isomeric PCs. This approach is comprised of two MS methods: a precursor ion scanning (PIS) of mass m/z 184 in positive mode (PIS m/z +184) and MS(3) fragmentation in negative mode, both performed on the same instrument, a hybrid triple quadrupole ion-trap mass spectrometer. The MS(3) experiment identified the FA composition and the relative abundance of isobaric and sn-1, sn-2 positional isomeric PC species, which were subsequently combined with absolute quantitative data obtained by PIS m/z +184 scan. This approach was applied to the analysis of a National Institute of Standards and Technology human blood plasma standard reference material (SRM 1950). We quantified more than 70 PCs and confirmed that a majority are present in isobaric and isomeric mixtures. The FA content determined by this method was comparable to that obtained using GC with flame ionization detection, supporting the quantitative nature of this MS method. This methodology will provide more in-depth biomarker information for clinical and mechanistic studies.

  14. Using Metal Complex Ion-Molecule Reactions in a Miniature Rectilinear Ion Trap Mass Spectrometer to Detect Chemical Warfare Agents

    Science.gov (United States)

    Graichen, Adam M.; Vachet, Richard W.

    2013-06-01

    The gas-phase reactions of a series of coordinatively unsaturated [Ni(L)n]y+ complexes, where L is a nitrogen-containing ligand, with chemical warfare agent (CWA) simulants in a miniature rectilinear ion trap mass spectrometer were investigated as part of a new approach to detect CWAs. Results show that upon entering the vacuum system via a poly(dimethylsiloxane) (PDMS) membrane introduction, low concentrations of several CWA simulants, including dipropyl sulfide (simulant for mustard gas), acetonitrile (simulant for the nerve agent tabun), and diethyl phosphite (simulant for nerve agents sarin, soman, tabun, and VX), can react with metal complex ions generated by electrospray ionization (ESI), thereby providing a sensitive means of detecting these compounds. The [Ni(L)n]2+ complexes are found to be particularly reactive with the simulants of mustard gas and tabun, allowing their detection at low parts-per-billion (ppb) levels. These detection limits are well below reported exposure limits for these CWAs, which indicates the applicability of this new approach, and are about two orders of magnitude lower than electron ionization detection limits on the same mass spectrometer. The use of coordinatively unsaturated metal complexes as reagent ions offers the possibility of further tuning the ion-molecule chemistry so that desired compounds can be detected selectively or at even lower concentrations.

  15. Ion suppression in the determination of clenbuterol in urine by solid-phase extraction atmospheric pressure chemical ionisation ion-trap mass spectrometry

    NARCIS (Netherlands)

    van Hout, M.W.J.; Niederlander, H.A G; de Zeeuw, R.A.; de Jong, G.J.

    2003-01-01

    Ion suppression effects were observed during the determination of clenbuterol in urine with solid-phase extraction/multiple-stage ion-trap mass spectrometry (SPE/MS3), despite the use of atmospheric pressure chemical ionisation. During SPE, a polymeric stationary phase (polydivinylbenzene) was appli

  16. Performance of the linear ion trap Orbitrap mass analyzer for qualitative and quantitative analysis of drugs of abuse and relevant metabolites in sewage water

    NARCIS (Netherlands)

    Bijlsma, L.; Emke, E.; Hernández, F.; de Voogt, P.

    2013-01-01

    This work illustrates the potential of liquid chromatography coupled to a hybrid linear ion trap Fourier Transform Orbitrap mass spectrometer for the simultaneous identification and quantification of 24 drugs of abuse and relevant metabolites in sewage water. The developed methodology consisted of a

  17. Flavor release measurement by atmospheric pressure chemical ionization ion trap mass spectrometry, construction of interface and mathematical modeling of release profiles

    DEFF Research Database (Denmark)

    Haahr, Anne-Mette; Madsen, Henrik; Smedsgaard, Jørn

    2003-01-01

    An instrumental on-line retronasal flavor analysis was developed to obtain information about the release of flavor compounds in expired air from humans during eating. The volatile flavor compounds were measured by ion trap mass spectrometry with an atmospheric pressure chemical ionization source...

  18. Analysis of wine volatile profile by purge-and-trap-gas chromatography-mass spectrometry. Application to the analysis of red and white wines from different Spanish regions.

    Science.gov (United States)

    Aznar, Margarita; Arroyo, Teresa

    2007-09-21

    The purge-and-trap extraction method, coupled to a gas chromatograph with mass spectrometry detection, has been applied to the determination of 26 aromatic volatiles in wine. The method was optimized, validated and applied to the analyses of 40 red and white wines from 7 different Spanish regions. Principal components analyses of data showed the correlation between wines of similar origin.

  19. Application of the Reversed-phase Liquid Chromatography Coupled to Ion Trap Mass Spectrometry with Principal Components Analysis for Metabonomics Studies of Scutellarin in Rat Urine

    Institute of Scientific and Technical Information of China (English)

    Xiao Rong RAN; Sheng Zhu SI; Qiong Lin LIANG; Guo An LUO

    2006-01-01

    Metabonomics, a novel systemic approach, was applied to studies of Traditional Chinese Medicine scutellarin in rat urine. The liquid chromatography coupled with ion trap mass spectrometry combined with PCA was used in this paper. With this methodology, two potential metabolites of scutellarin were detected and the nine ions responsible for the gender variation and one ion for the dosage variation were found.

  20. Solvent-driven electron trapping and mass transport in reduced graphites to access perfect graphene

    Science.gov (United States)

    Vecera, Philipp; Holzwarth, Johannes; Edelthalhammer, Konstantin F.; Mundloch, Udo; Peterlik, Herwig; Hauke, Frank; Hirsch, Andreas

    2016-08-01

    Herein, we report on a significant discovery, namely, the quantitative discharging of reduced graphite forms, such as graphite intercalation compounds, graphenide dispersions and graphenides deposited on surfaces with the simple solvent benzonitrile. Because of its comparatively low reduction potential, benzonitrile is reduced during this process to the radical anion, which exhibits a red colour and serves as a reporter molecule for the quantitative determination of negative charges on the carbon sheets. Moreover, this discovery reveals a very fundamental physical-chemical phenomenon, namely a quantitative solvent reduction induced and electrostatically driven mass transport of K+ ions from the graphite intercalation compounds into the liquid. The simple treatment of dispersed graphenides suspended on silica substrates with benzonitrile leads to the clean conversion to graphene. This unprecedented procedure represents a rather mild, scalable and inexpensive method for graphene production surpassing previous wet-chemical approaches.

  1. Performance of the linear ion trap Orbitrap mass analyzer for qualitative and quantitative analysis of drugs of abuse and relevant metabolites in sewage water

    OpenAIRE

    Bijlsma, Lubertus; Emke, Erik; Hernández Hernández, Félix; Voogt, Pim de

    2013-01-01

    This work illustrates the potential of liquid chromatography coupled to a hybrid linear ion trap Fourier Transform Orbitrap mass spectrometer for the simultaneous identification and quantification of 24 drugs of abuse and relevant metabolites in sewage water. The developed methodology consisted of automatic solid-phase extraction using Oasis HLB cartridges, chromatographic separation of the targeted drugs, full-scan accurate mass data acquisition under positive electrospray ionization mode ov...

  2. Liquid chromatography tandem mass spectrometric quantitation of sulfamethazine and its metabolites: direct analysis of swine urine by triple quadrupole and by ion trap mass spectrometry.

    Science.gov (United States)

    Bartolucci, G; Pieraccini, G; Villanelli, F; Moneti, G; Triolo, A

    2000-01-01

    This work describes a new method for the quantitation of trace amounts of sulfamethazine (SMZ) and its main metabolite, N4-acetylsulfamethazine (Ac-SMZ), in swine urine, using high-performance liquid chromatography (HPLC) tandem mass spectrometric analysis of crude urine after addition of internal standard and simple dilution with water. The aim was to determine whether residues of this sulfamidic drug, normally administered to swine in order to prevent infectious diseases, were present in urine at levels lower than those permitted by regulatory authorities before human consumption (EU Project SMT, contract number CT 96-2092). A 10 microL volume of diluted urine was injected into a very short, narrow-bore chromatographic column (Zorbax SB-C18 2.1 i. d. x30 mm length, 3.5 microm pore size). Elution of the analytes of interest was achieved in less than seven minutes using a rapid gradient (from 20 to 80% methanol in 3 minutes). Either a PE Sciex API 365 triple quadrupole (QqQ), operated in the selected reaction monitoring (SRM) mode, or a Finnigan LCQ ion trap (IT) mass spectrometer, operated in narrow-range product ion scan, was used as the final detector. Electrospray (ESI) was used as the ionization technique. A comparison of the two tandem mass spectrometers was performed by analyzing the same set of test samples, at three concentration levels, on three different days. Linearity of responses of the calibration standards, intra- and inter-assay precision of the samples, specificity and limits of detection were evaluated for both systems. Both the QqQ and the IT instrument was suitable for rapid, sensitive and specific determination of the analytes, although the overall performance of the QqQ was slightly superior in terms of linearity, precision and sensitivity.

  3. Appropriate choice of collision-induced dissociation energy for qualitative analysis of notoginsenosides based on liquid chromatography hybrid ion trap time-of-flight mass spectrometry.

    Science.gov (United States)

    Wang, Guang-Ji; Fu, Han-Xu; Xiao, Jing-Cheng; Ye, Wei; Rao, Tai; Shao, Yu-Hao; Kang, Dian; Xie, Lin; Liang, Yan

    2016-04-01

    Liquid chromatography hybrid ion trap/time-of-flight mass spectrometry possessesd both the MS(n) ability of ion trap and the excellent resolution of a time-of-flight, and has been widely used to identify drug metabolites and determine trace multi-components for in natural products. Collision energy, one of the most important factors in acquiring MS(n) information, could be set freely in the range of 10%-400%. Herein, notoginsenosides were chosen as model compounds to build a novel methodology for the collision energy optimization. Firstly, the fragmental patterns of the representatives for the authentic standards of protopanaxadiol-type and protopanaxatriol-type notoginsenosides authentic standards were obtained based on accurate MS(2) and MS(3) measurements via liquid chromatography hybrid ion trap/time-of-flight mass spectrometry. Then the extracted ion chromatograms of characteristic product ions of notoginsenosides in Panax Notoginseng Extract, which were produced under a series of collision energies and, were compared to screen out the optimum collision energies values for MS(2) and MS(3). The results demonstrated that the qualitative capability of liquid chromatography hybrid ion trap/time-of-flight mass spectrometry was greatly influenced by collision energies, and 50% of MS(2) collision energy was found to produce the highest collision-induced dissociation efficiency for notoginsenosides. BesidesAddtionally, the highest collision-induced dissociation efficiency appeared when the collision energy was set at 75% in the MS(3) stage.

  4. Structural characterization of metabolites of the X-ray contrast agent iopromide in activated sludge using ion trap mass spectrometry.

    Science.gov (United States)

    Pérez, Sandra; Eichhorn, Peter; Celiz, Mary Dawn; Aga, Diana S

    2006-03-15

    Identification of degradation products of environmental contaminants is a challenging task because not only are they present in very low concentrations but they are also mixed with complex matrixes that interfere with detection. This work illustrates a simple approach using ion trap mass spectrometry combined with H/D-exchange experiments to elucidate the structures of iopromide metabolites formed during biodegradation in activated sludge. Iopromide is an X-ray contrast agent that has been detected frequently in effluents of wastewater treatment plants and in surface waters due to its persistence and high usage. Three metabolites produced by oxidation of the primary alcohols (forming carboxylates) on the side chains of iopromide were identified in a batch reactor with mixed liquor from a conventional activated sludge. Derivatization of the carboxylic acid to form a methyl ester and interpretation of the MS2 data of this derivative aided in the confirmation of the identities of these metabolites. Furthermore, one metabolite formed by dehydroxylation at the two side chains was identified in a batch reactor with mixed liquor from a nitrifying activated sludge. The MS2 fragmentation pattern of iopromide and its metabolites revealed that the iodinated ring remains intact and that minor transformations in the structure occur during biodegradation of iopromide in biological wastewater treatment plants.

  5. Metabolism of SFZ—47 in chicken embryo by liquid chroma—tography—electrospray ion trap mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    DONGQing-Guang; GUJing-Kai; ZHONGDa-Fang; JPaulFAWCETT; ZHOUHui

    2003-01-01

    AIM:To develop an alternative method for investigation of drug metabolism by fertilized chicken eggs using 3H-1,2-dihydro-2-(4-methyl-phenylamino) methyl-1-pyrrolizinone (SFZ-47) as a probe drug. METHODS:SFZ-47(15 mg) was injected into the albumen of eggs from standardized breed chickens previously incubated for 10d. After 72 h of further incubation, the allantoic liquid was subjected to solid phase extraction on XAD-2 columns and analyzed by liquid chromatography-electrospray ion trap mass spectrometry method. RESULTS: Three major metabolites were identified, namely 4-(3H-1,2-dihydro-1-pyrrolizinone-2-methyl-amino) benzyl alcohol (SFZ-47-OH), 4-(3H-1,2-dihydro-1-pyrrolizinone-2-methyl-amino)-benzoic acid (SFZ-47-COOH), and its glucuronide conjugates. The metabolic profile was little different from that previously found in rabbits and dogs. CONCLUSION: The result demonstrates the usefulness of the fertilized chicken egg as a convenient source of both phase I and phase Ⅱ metabolites for further metabolism studies of SFZ-47.

  6. Comprehensive lipidome analysis by shotgun lipidomics on a hybrid quadrupole-orbitrap-linear ion trap mass spectrometer.

    Science.gov (United States)

    Almeida, Reinaldo; Pauling, Josch Konstantin; Sokol, Elena; Hannibal-Bach, Hans Kristian; Ejsing, Christer S

    2015-01-01

    Here we report on the application of a novel shotgun lipidomics platform featuring an Orbitrap Fusion mass spectrometer equipped with an automated nanoelectrospray ion source. To assess the performance of the platform for in-depth lipidome analysis, we evaluated various instrument parameters, including its high resolution power unsurpassed by any other contemporary Orbitrap instrumentation, its dynamic quantification range and its efficacy for in-depth structural characterization of molecular lipid species by quadrupole-based higher-energy collisional dissociation (HCD), and ion trap-based resonant-excitation collision-induced dissociation (CID). This evaluation demonstrated that FTMS analysis with a resolution setting of 450,000 allows distinguishing isotopes from different lipid species and features a linear dynamic quantification range of at least four orders of magnitude. Evaluation of fragmentation analysis demonstrated that combined use of HCD and CID yields complementary fragment ions of molecular lipid species. To support global lipidome analysis, we designed a method, termed MS(ALL), featuring high resolution FTMS analysis for lipid quantification, and FTMS(2) analysis using both HCD and CID and ITMS(3) analysis utilizing dual CID for in-depth structural characterization of molecular glycerophospholipid species. The performance of the MS(ALL) method was benchmarked in a comparative analysis of mouse cerebellum and hippocampus. This analysis demonstrated extensive lipidome quantification covering 311 lipid species encompassing 20 lipid classes, and identification of 202 distinct molecular glycerophospholipid species when applying a novel high confidence filtering strategy. The work presented here validates the performance of the Orbitrap Fusion mass spectrometer for in-depth lipidome analysis.

  7. Screening for DNA adducts by data-dependent constant neutral loss-triple stage mass spectrometry with a linear quadrupole ion trap mass spectrometer.

    Science.gov (United States)

    Bessette, Erin E; Goodenough, Angela K; Langouët, Sophie; Yasa, Isil; Kozekov, Ivan D; Spivack, Simon D; Turesky, Robert J

    2009-01-15

    A two-dimensional linear quadrupole ion trap mass spectrometer (LIT/MS) was employed to simultaneously screen for DNA adducts of environmental, dietary, and endogenous genotoxicants, by data-dependent constant neutral loss scanning followed by triple-stage mass spectrometry (CNL-MS3). The loss of the deoxyribose (dR) from the protonated DNA adducts ([M + H - 116]+) in the MS/MS scan mode triggered the acquisition of MS3 product ion spectra of the aglycone adducts [BH2]+. Five DNA adducts of the tobacco carcinogen 4-aminobiphenyl (4-ABP) were detected in human hepatocytes treated with 4-ABP, and three DNA adducts of the cooked-meat carcinogen 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) were identified in the livers of rats exposed to MeIQx, by the CNL-MS3 scan mode. Buccal cell DNA from tobacco smokers was screened for DNA adducts of various classes of carcinogens in tobacco smoke including 4-ABP, 2-amino-9H-pyrido[2,3-b]indole (AalphaC), and benzo[a]pyrene (BaP); the cooked-meat carcinogens MeIQx, AalphaC, and 2-amino-1-methyl-6-phenylmidazo[4,5-b]pyridine (PhIP); and the lipid peroxidation products acrolein (AC) and trans-4-hydroxynonenal (HNE). The CNL-MS3 scanning technique can be used to simultaneously screen for multiple DNA adducts derived from different classes of carcinogens, at levels of adduct modification approaching 1 adduct per 108 unmodified DNA bases, when 10 microg of DNA is employed for the assay.

  8. A Generic Multiple Reaction Monitoring Based Approach for Plant Flavonoids Profiling Using a Triple Quadrupole Linear Ion Trap Mass Spectrometry

    Science.gov (United States)

    Yan, Zhixiang; Lin, Ge; Ye, Yang; Wang, Yitao; Yan, Ru

    2014-06-01

    Flavonoids are one of the largest classes of plant secondary metabolites serving a variety of functions in plants and associating with a number of health benefits for humans. Typically, they are co-identified with many other secondary metabolites using untargeted metabolomics. The limited data quality of untargeted workflow calls for a shift from the breadth-first to the depth-first screening strategy when a specific biosynthetic pathway is focused on. Here we introduce a generic multiple reaction monitoring (MRM)-based approach for flavonoids profiling in plants using a hybrid triple quadrupole linear ion trap (QTrap) mass spectrometer. The approach includes four steps: (1) preliminary profiling of major aglycones by multiple ion monitoring triggered enhanced product ion scan (MIM-EPI); (2) glycones profiling by precursor ion triggered EPI scan (PI-EPI) of major aglycones; (3) comprehensive aglycones profiling by combining MIM-EPI and neutral loss triggered EPI scan (NL-EPI) of major glycone; (4) in-depth flavonoids profiling by MRM-EPI with elaborated MRM transitions. Particularly, incorporation of the NH3 loss and sugar elimination proved to be very informative and confirmative for flavonoids screening. This approach was applied for profiling flavonoids in Astragali radix ( Huangqi), a famous herb widely used for medicinal and nutritional purposes in China. In total, 421 flavonoids were tentatively characterized, among which less than 40 have been previously reported in this medicinal plant. This MRM-based approach provides versatility and sensitivity that required for flavonoids profiling in plants and serves as a useful tool for plant metabolomics.

  9. Target identification of volatile metabolites to allow the differentiation of lactic acid bacteria by gas chromatography-ion mobility spectrometry.

    Science.gov (United States)

    Gallegos, Janneth; Arce, Cristina; Jordano, Rafael; Arce, Lourdes; Medina, Luis M

    2017-04-01

    The purpose of this work was to study the potential of gas chromatography-ion mobility spectrometry (GC-IMS) to differentiate lactic acid bacteria (LAB) through target identification and fingerprints of volatile metabolites. The LAB selected were used as reference strains for their influence in the flavour of cheese. The four strains of LAB can be distinguished by the fingerprints generated by the volatile organic compounds (VOCs) emitted. 2-butanone, 2-pentanone, 2-heptanone and 3-methyl-1-butanol were identified as relevant VOCs for Lactobacillus casei and Lactobacillus paracasei subsp. paracasei. 2-Butanone and 3-methyl-1-butanol were identified in Lactococcus lactis subsp. lactis and Lactococcus cremoris subsp. cremoris. The IMS signals monitoring during a 24-30h period showed the growth of the LAB in vitro. The results demonstrated that GC-IMS is a useful technology for bacteria recognition and also for screening the aromatic potential of new isolates of LAB.

  10. Triggers of Permo-Triassic boundary mass extinction in South China: The Siberian Traps or Paleo-Tethys ignimbrite flare-up?

    Science.gov (United States)

    He, Bin; Zhong, Yu-Ting; Xu, Yi-Gang; Li, Xian-Hua

    2014-09-01

    Assessment of the synchroneity between the Siberian Traps and the Permo-Triassic boundary (PTB) mass extinction has led to the proposition that the Siberian flood volcanism was responsible for the severest biotic crisis in the Phanerozoic. However, recent studies suggest that the Siberian Traps may have postdated the main extinction horizon. In this paper, we demonstrate, using stratigraphy, a time and intensity coincidence between PTB volcanic ash and the main extinction horizon. Geochemistry of the PTB volcanic ashes in five sections in South China indicates that they were derived from continental magmatic arc. Zircons extracted from the PTB volcanic ashes have negative εHf(t) (- 12.9 to - 2.0) and δ18O (6.8 to 10.9‰), consistent with an acidic volcanism and a crustal-derived origin, and therefore exclude a genetic link between the PTB mass extinction and the Siberian Traps. On the basis of spatial variation in the number of the PTB volcanic ash layers and the thickness of the ash layers in South China, we propose that the PTB volcanic ash may be related to Paleo-Tethys continental arc magmatism in the Kunlun area. Ignimbrite flare-up related to rapid plate subduction during the final assemblage of the Pangea super-continent may have generated a volcanic winter, which eventually triggered the collapse of ecosystem and ultimately mass extinction at the end of the Permian. The Siberian Traps may have been responsible for a greenhouse effect and so have been responsible for both a second pulse of the extinction event and Early Triassic ecological evolution.

  11. Penning-trap mass spectrometry of highly charged, neutron-rich Rb and Sr isotopes in the vicinity of $A\\approx100$

    CERN Document Server

    Simon, V V; Chowdhury, U; Eberhardt, B; Ettenauer, S; Gallant, A T; Mané, E; Simon, M C; Delheij, P; Pearson, M R; Audi, G; Gwinner, G; Lunney, D; Schatz, H; Dilling, J

    2012-01-01

    The neutron-rich mass region around $A\\approx100$ presents challenges for modeling the astrophysical $r$-process because of rapid shape transitions. We report on mass measurements using the TITAN Penning trap at TRIUMF-ISAC to attain more reliable theoretical predictions of $r$-process nucleosynthesis paths in this region. A new approach using highly charged ($q=15+$) ions has been applied which considerably saves measurement time and preserves accuracy. New mass measurements of neutron-rich $^{94,97,98}$Rb and $^{94,97-99}$Sr have uncertainties of less than 4 keV and show deviations of up to 11$\\sigma$ to previous measurements. An analysis using a parameterized $r$-process model is performed and shows that mass uncertainties for the A=90 abundance region are eliminated.

  12. The use of online heart-cutting high-performance liquid chromatography coupled with linear ion trap mass spectrometry in the identification of impurities in vidarabine monophosphate.

    Science.gov (United States)

    Wang, Hang; Xu, Tongzhou; Yuan, Jiaojian

    2017-02-17

    It is difficult to identify unknown impurities in nucleotide analogues by mass spectrometry because mass-spectrometry-incompatible mobile phases need to be used to separate the major ingredient from impurities. In this study, vidarabine monophosphate was selected, and unknown impurities were identified by online heart-cutting two-dimensional high-performance liquid chromatography and linear ion trap mass spectrometry. The one-dimensional reversed-phase column was filled with a mobile phase containing nonvolatile salt. In two-dimensional high-performance liquid chromatography, we used an Acclaim Q1 column with volatile salt, and the detection wavelength was 260 nm. The mass spectrum was scanned in positive- and negative-ion mode. The online heart-cutting and online demineralization technique ensured that the mobile phase was compatible with mass spectrometry; seven impurities were identified by MS(2) and MS(3) fragments. The mass fragmentation patterns of these impurities were investigated. The two isomers were semiprepared and complemented by nuclear magnetic resonance. The results were further compared with those of normal-phase high-performance liquid chromatography with mass spectrometry. The online heart-cutting two-dimensional high-performance liquid chromatography with mass spectrometry was superior in identifying more impurities. The method solves the problem of incompatibility between the mobile phase and mass spectrometry, so it is suitable for identifying unknown impurities. This method may also be used for investigating impurities in other nucleotide analogues.

  13. Identifying interacting proteins of a Caenorhabditis elegans voltage-gated chloride channel CLH-1 using GFP-Trap and mass spectrometry.

    Science.gov (United States)

    Zhou, Zi-Liang; Jiang, Jing; Yin, Jiang-An; Cai, Shi-Qing

    2014-06-25

    Chloride channels belong to a superfamily of ion channels that permit passive passage of anions, mainly chloride, across cell membrane. They play a variety of important physiological roles in regulation of cytosolic pH, cell volume homeostasis, organic solute transport, cell migration, cell proliferation, and differentiation. However, little is known about the functional regulation of these channels. In this study, we generated an integrated transgenic worm strain expressing green fluorescence protein (GFP) fused CLC-type chloride channel 1 (CLH-1::GFP), a voltage-gated chloride channel in Caenorhabditis elegans (C. elegans). CLH-1::GFP was expressed in some unidentified head neurons and posterior intestinal cells of C. elegans. Interacting proteins of CLH-1::GFP were purified by GFP-Trap, a novel system for efficient isolation of GFP fusion proteins and their interacting factors. Mass spectrometry (MS) analysis revealed that a total of 27 high probability interacting proteins were co-trapped with CLHp-1::GFP. Biochemical evidence showed that eukaryotic translation elongation factor 1 (EEF-1), one of these co-trapped proteins identified by MS, physically interacted with CLH-1, in consistent with GFP-Trap experiments. Further immunostaining data revealed that the protein level of CLH-1 was significantly increased upon co-expression with EEF-1. These results suggest that the combination of GFP-Trap purification with MS is an excellent tool to identify novel interacting proteins of voltage-gated chloride channels in C. elegans. Our data also show that EEF-1 is a regulator of voltage-gated chloride channel CLH-1.

  14. Development of a linear ion trap/orthogonal-time-of-flight mass spectrometer for time-dependent observation of product ions by ultraviolet photodissociation of peptide ions.

    Science.gov (United States)

    Kim, Tae-Young; Schwartz, Jae C; Reilly, James P

    2009-11-01

    A hybrid linear ion trap/orthogonal time-of-flight (TOF) mass spectrometer has been developed to observe time-dependent vacuum ultraviolet photodissociation product ions. In this apparatus, a reflectron TOF mass analyzer is orthogonally interfaced to an LTQ using rf-only octopole and dc quadrupole ion guides. Precursor ions are generated by electrospray ionization and isolated in the ion trap. Subsequently they are directed to the TOF source where photodissociation occurs and product ions are extracted for mass analysis. To detect photodissociation product ions having axially divergent trajectories, a large rectangular detector is utilized. With variation of the time between photodissociation and orthogonal extraction in the TOF source, product ions formed over a range of times after photoexcitation can be sampled. Time-dependent observation of product ions following 157 nm photodissociation of a singly charged tryptic peptide ion (NWDAGFGR) showed that prompt photofragment ions (x- and v-type ions) dominate the tandem mass spectrum up to 1 micros after the laser shot, but the intensities of low energy thermal fragment ions (y-type ions) become comparable several microseconds later. Different proton mobilization time scales were observed for arginine- and lysine-terminated tryptic peptides.

  15. Standing on the shoulders of giants: Trojan Earths and vortex trapping in low mass self-gravitating protoplanetary disks of gas and solids

    CERN Document Server

    Lyra, W; Klahr, H; Piskunov, N

    2008-01-01

    Centimeter and meter sized solid particles in protoplanetary disks are trapped within long lived high pressure regions, creating opportunities for collapse into planetesimals and planetary embryos. We study the accumulations in the stable Lagrangian points of a giant planet, as well as in the Rossby vortices launched at the edges of the gap it carves. We employ the Pencil Code, tracing the solids with a large number of interacting Lagrangian particles, usually 100,000. For particles of 1 cm to 10 cm radii, gravitational collapse occurs in the Lagrangian points in less than 200 orbits. For 5 cm particles, a 2 Earth mass planet is formed. For 10 cm, the final maximum collapsed mass is around 3 Earth masses. The collapse of the 1 cm particles is indirect, following the timescale of depletion of gas from the tadpole orbits. In the edges of the gap vortices are excited, trapping preferentially particles of 30 cm radii. The rocky planet that is formed is as massive as 17 Earth masses, constituting a Super-Earth. By...

  16. High-precision Penning trap mass measurements of 9,10Be and the one-neutron halo nuclide 11Be

    Science.gov (United States)

    Ringle, R.; Brodeur, M.; Brunner, T.; Ettenauer, S.; Smith, M.; Lapierre, A.; Ryjkov, V. L.; Delheij, P.; Drake, G. W. F.; Lassen, J.; Lunney, D.; Dilling, J.

    2009-05-01

    Penning trap mass measurements of 9Be, 10Be (t1 / 2 = 1.51 My), and the one-neutron halo nuclide 11Be (t1 / 2 = 13.8 s) have been performed using TITAN at TRIUMF. The resulting 11Be mass excess (ME = 20 177.60 (58) keV) is in agreement with the current Atomic Mass Evaluation (AME03) [G. Audi, et al., Nucl. Phys. A 729 (2003) 337] value, but is over an order of magnitude more precise. The precision of the mass values of 9,10Be have been improved by about a factor of four and reveal a ≈ 2 σ deviation from the AME mass values. Results of new atomic physics calculations are presented for the isotope shift of 11Be relative to 9Be, and it is shown that the new mass values essentially remove atomic mass uncertainties as a contributing factor in determining the relative nuclear charge radius from the isotope shift. The new mass values of 10,11Be also allow for a more precise determination of the single-neutron binding energy of the halo neutron in 11Be.

  17. Accelerated solvent extraction followed by on-line solid-phase extraction coupled to ion trap LC/MS/MS for analysis of benzalkonium chlorides in sediment samples

    Science.gov (United States)

    Ferrer, I.; Furlong, E.T.

    2002-01-01

    Benzalkonium chlorides (BACs) were successfully extracted from sediment samples using a new methodology based on accelerated solvent extraction (ASE) followed by an on-line cleanup step. The BACs were detected by liquid chromatography/ion trap mass spectrometry (LC/MS) or tandem mass spectrometry (MS/MS) using an electrospray interface operated in the positive ion mode. This methodology combines the high efficiency of extraction provided by a pressurized fluid and the high sensitivity offered by the ion trap MS/MS. The effects of solvent type and ASE operational variables, such as temperature and pressure, were evaluated. After optimization, a mixture of acetonitrile/water (6:4 or 7:3) was found to be most efficient for extracting BACs from the sediment samples. Extraction recoveries ranged from 95 to 105% for C12 and C14 homologues, respectively. Total method recoveries from fortified sediment samples, using a cleanup step followed by ASE, were 85% for C12BAC and 79% for C14-BAC. The methodology developed in this work provides detection limits in the subnanogram per gram range. Concentrations of BAC homologues ranged from 22 to 206 ??g/kg in sediment samples from different river sites downstream from wastewater treatment plants. The high affinity of BACs for soil suggests that BACs preferentially concentrate in sediment rather than in water.

  18. 40 CFR 75.15 - Special provisions for measuring Hg mass emissions using the excepted sorbent trap monitoring...

    Science.gov (United States)

    2010-07-01

    ... stack flow monitor, corrected for the stack gas moisture content. For each pair of sorbent traps...; (c) A certified flow monitoring system is required; (d) Correction for stack gas moisture content is... proportional to the stack gas volumetric flow rate. (f) At the beginning and end of each sample...

  19. Characterization of Ni(II) complexes of Schiff bases of amino acids and (S)-N-(2-benzoylphenyl)-1-benzylpyrrolidine-2-carboxamide using ion trap and QqTOF electrospray ionization tandem mass spectrometry

    NARCIS (Netherlands)

    Jirasko, Robert; Holcapek, Michal; Kolarova, Lenka; Nadvornik, Milan; Popkov, Alexander

    2008-01-01

    This work demonstrates the application of electrospray ionization mass spectrometry (ESI-MS) using two different mass analyzers, ion trap and hybrid quadrupole time-of-flight (QqTOF) mass analyzer, for the structural characterization of Ni(II) complexes of Schiff bases of (S)-N-(2-benzoylphenyl)-1-b

  20. Microfabricated ion trap array

    Science.gov (United States)

    Blain, Matthew G.; Fleming, James G.

    2006-12-26

    A microfabricated ion trap array, comprising a plurality of ion traps having an inner radius of order one micron, can be fabricated using surface micromachining techniques and materials known to the integrated circuits manufacturing and microelectromechanical systems industries. Micromachining methods enable batch fabrication, reduced manufacturing costs, dimensional and positional precision, and monolithic integration of massive arrays of ion traps with microscale ion generation and detection devices. Massive arraying enables the microscale ion traps to retain the resolution, sensitivity, and mass range advantages necessary for high chemical selectivity. The reduced electrode voltage enables integration of the microfabricated ion trap array with on-chip circuit-based rf operation and detection electronics (i.e., cell phone electronics). Therefore, the full performance advantages of the microfabricated ion trap array can be realized in truly field portable, handheld microanalysis systems.

  1. A lethal ovitrap-based mass trapping scheme for dengue control in Australia: II. Impact on populations of the mosquito Aedes aegypti.

    Science.gov (United States)

    Rapley, L P; Johnson, P H; Williams, C R; Silcock, R M; Larkman, M; Long, S A; Russell, R C; Ritchie, S A

    2009-12-01

    In Cairns, Australia, the impacts on Aedes aegypti L. (Diptera: Culicidae) populations of two types of 'lure & kill' (L&K) lethal ovitraps (LOs), the standard lethal ovitrap (SLO) and the biodegradable lethal ovitrap (BLO) were measured during three mass-trapping interventions. To assess the efficacy of the SLO, two interventions (one dry season and one wet season) were conducted in three discrete areas, each lasting 4 weeks, with the following treatments: (i) SLOs (>200 traps, approximately 4/premise), BG-sentinel traps (BGSs; approximately 15, 1/premise) and larval control (container reduction and methoprene treatment) and (ii) larval control alone, and (iii) untreated control. Female Ae. aegypti populations were monitored for 4 weeks pre- and post-treatment in all three areas using BGSs and sticky ovitraps (SOs) or non-lethal regular ovitraps (ROs). In the dry season, 206 SLOs and 15 BGSs set at 54 and 15 houses, respectively, caught and killed an estimated 419 and 73 female Ae. aegypti, respectively. No significant decrease in collection size of female Ae. aegypti could be attributed to the treatments. In the wet season, 243 SLOs and 15 BGSs killed approximately 993 and 119 female Ae. aegypti, respectively. The mean number of female Ae. aegypti collected after 4 weeks with SOs and BGSs was significantly less than the control (LSD post-hoc test). The third mass-trapping intervention was conducted using the BLO during the wet season in Cairns. For this trial, three treatment areas were each provided with BLOs (>500, approximately 4/premise) plus larval control, and an untreated control area was designated. Adult female Ae. aegypti were collected for 4 weeks pre- and post-treatment using 15 BGSs and 20 SOs. During this period, 53.2% of BLOs contained a total of 6654 Ae. aegypti eggs. Over the intervention period, collections of Ae. aegypti in the treatment areas were significantly less than in the control area for BGSs but not SOs. An influx of relatively large

  2. Nuclear structure studies in the xenon and radon region and the discovery of a new radon isotope by Penning trap mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Neidherr, Dennis

    2010-04-28

    Nowadays high-precision mass measurements based on Penning traps allow a deep insight into the fundamental properties of nucleonic matter. To this end, the cyclotron frequency {nu}{sub c}=qB=(2{pi}m) of an ion confined in a strong, homogeneous magnetic field B is determined. At the ISOLTRAP mass spectrometer at ISOLDE / CERN the masses of short-lived radioactive nuclei with half-lives down to several ten ms can be measured with an uncertainty in the order of 10{sup -8} and below. ISOLTRAP consists of an RFQ cooler and buncher to cool and accumulate the ions coming from ISOLDE and a double Penning trap system to first clean the ion samples and finally perform the mass measurements. Within this thesis the masses of neutron rich xenon and radon isotopes, namely {sup 138-146}Xe and {sup 223-229}Rn were determined, eleven of them for the first time. {sup 229}Rn was even discovered in this experiment and its half-life could be determined to 12{sub -1.3}{sup +1.2} s. Since the mass reflects all interactions inside the nucleus it is a unique fingerprint of the nuclide of interest. One of these interactions, the proton-neutron interaction, leads for example to the onset of deformation. The aim of this thesis is to investigate a possible connection be- tween collective effects in nuclei, like the onset of deformation, and double-differences of binding energies, so called {delta}V{sub pn} values. Especially in the here presented areas these {delta}V{sub pn} values show a very unusual behavior and can not be explained with simple orbital overlapping arguments. One explanation could be the occurrence of octupolar deformation in these regions, which is usually probed with other experimental techniques. However, a quantitative description of the influence of such type of deformation on {delta}V{sub pn} is still not possible with modern theories. (orig.)

  3. [Rapid screening and confirming carcinogenic banned azo colorants in textiles by high performance liquid chromatography-linear ion trap/orbitrap high-resolution mass spectrometry].

    Science.gov (United States)

    Yun, Huan; Liu, Xin; Wang, Jing; Yan, Hua; Cui, Fengyun; Zhang, Zhaohui

    2013-09-01

    A method of high performance liquid chromatography-linear ion trap/orbitrap highresolution mass spectrometry (HPLC-LTP/Orbitrap MS) was ued to screen and confirm-banned azo colorants in textiles rapidly. The analytes were reduced to carcinogenic aromatic amines with sodium dithionite in citrate buffer solution. The reduced solution was extracted bydiatomite, and loadd onto an Acquity UPLC BEH C18 column (50 mm x 2.1 MM. 1.7 microm) with a gradient elution of methanol and 0.1% (v/v) methane acid aqueous solution, and finally detected by linear ion trap/orbitrap high-resolution mass spectrometry in positive ESI mode. In mass spectrometry method, the MS spectrum of high-resolution and the collision induced dissociation (CID) spectrum of data-dependent scan mode were used for screening analysis and conformation, respectively. The calibration curves showed a good linearity in the range of 0.05 -2.00 mg/b, and the correlation coefficients (r) were higher than 0.99. By detecting spiked samples, the limits of quantification were 0.08 mg/kg for all the residues and the recoveries were in the range of 65.5% - 111.5% with the relative standard deviations (RSDs) between 0.87% and 2.49%. The results indicate that the method is simple, rapid, sensitive and suitable for the qualitative and quantitative analysis of carcinogenic aromatic amines in textiles.

  4. Generation of highly charged peptide and protein ions by atmospheric pressure matrix-assisted infrared laser desorption/ionization ion trap mass spectrometry.

    Science.gov (United States)

    König, Simone; Kollas, Oliver; Dreisewerd, Klaus

    2007-07-15

    We show that highly charged ions can be generated if a pulsed infrared laser and a glycerol matrix are employed for atmospheric pressure matrix-assisted laser desorption/ionization mass spectrometry with a quadrupole ion trap. Already for small peptides like bradykinin, doubly protonated ions form the most abundant analyte signal in the mass spectra. The center of the charge-state distribution increases with the size of the analyte. For example, insulin is detected with a most abundant ion signal corresponding to a charge state of four, whereas for cytochrome c, the 10 times protonated ion species produces the most intense signal. Myoglobin is observed with up to 13 charges. The high m/z ratios allow us to use the Paul trap for the detection of MALDI-generated protein ions that are, owing to their high molecular weight, not amenable in their singly protonated charge state. Formation of multiple charges critically depends on the addition of diluted acid to the analyte-matrix solution. Tandem mass spectra generated by collision-induced dissociation of doubly charged peptides are also presented. The findings allow speculations about the involvement of electrospray ionization processes in these MALDI experiments.

  5. Metabonomic Study of Biochemical Changes in Human Hair of Heroin Abusers by Liquid Chromatography Coupled with Ion Trap-Time of Flight Mass Spectrometry.

    Science.gov (United States)

    Xie, Pu; Wang, Tie-jie; Yin, Guo; Yan, Yan; Xiao, Li-he; Li, Qing; Bi, Kai-shun

    2016-01-01

    Hair analysis is with the advantage of non-invasive collection and long surveillance window. The present study employed a sensitive and reliable liquid chromatography coupled with ion trap-time of flight mass spectrometry method to study the metabonomic characters in the hair of 58 heroin abusers and 72 non-heroin abusers. Results indicated that certain endogenous metabolites, such as sorbitol and cortisol, were accelerated, and the level of arachidonic acid, glutathione, linoleic acid, and myristic acid was decreased in hair of heroin abusers. The metabonomic study is helpful for further understanding of heroin addiction and clinical diagnosis.

  6. A Micro Cylindrical Ion Trap (5-CIT) Micro Mass Spectrometer Instrument System (5MSIS) for NASA Planetary Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The project aims to develop a miniature packaging platform for the integration of MEMS mass spectrometer components to form the basis of a Micro Mass Spectrometer...

  7. High-throughput walkthrough detection portal for counter terrorism: detection of triacetone triperoxide (TATP) vapor by atmospheric-pressure chemical ionization ion trap mass spectrometry.

    Science.gov (United States)

    Takada, Yasuaki; Nagano, Hisashi; Suzuki, Yasutaka; Sugiyama, Masuyuki; Nakajima, Eri; Hashimoto, Yuichiro; Sakairi, Minoru

    2011-09-15

    With the aim of improving security, a high-throughput portal system for detecting triacetone triperoxide (TATP) vapor emitted from passengers and luggage was developed. The portal system consists of a push-pull air sampler, an atmospheric-pressure chemical ionization (APCI) ion source, and an explosives detector based on mass spectrometry. To improve the sensitivity of the explosives detector, a novel linear ion trap mass spectrometer with wire electrodes (wire-LIT) is installed in the portal system. TATP signals were clearly obtained 2 s after the subject under detection passed through the portal system. Preliminary results on sensitivity and throughput show that the portal system is a useful tool for preventing the use of TATP-based improvised explosive devices by screening persons in places where many people are coming and going.

  8. Methanol chemical ionization quadrupole ion trap mass spectrometry of O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothiolate (VX) and its degradation products.

    Science.gov (United States)

    Rohrbaugh, D K

    2000-10-06

    Mass spectrometric analysis of O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothiolate (VX) degradation products by electron ionization produces extensive fragmentation with little or no molecular ion information making product identification difficult. Milder chemical ionization (CI) is commonly used to provide molecular mass and structure confirmation. In this study, methanol was used as a CI reagent in combination with an ion trap detector for detection and identification of over 30 compounds present in a thermally degraded sample of VX. The use of methanol provides superior results for this class of compounds with less fragmentation than commonly observed with gas reagents and offers logistical advantages for on-site analysis by being easier to transport and safer to use than gas cylinders.

  9. Penning-trap mass spectrometry of neutron-rich copper isotopes for probing the Z = 28 and N = 50 shell closures

    CERN Multimedia

    Manea, V

    We propose to perform a Penning-trap mass measurement of $^{79}$Cu. This exotic N = 50 isotone is the last frontier before the doubly-magic $^{78}$Ni and will greatly improve our knowledge of shell evolution. In the same run, we propose $^{77-78}$Cu mass measurements, as well as the search for a possible isomer in $^{76m}$Cu. The data will help to clarify the structure of the odd proton in the Cu isotopes, the influence on the Z = 28 proton core of the νg$_{9/2}$ orbital filling and the impact of the proton-neutron residual interaction on the strength of the N = 50 shell closure.

  10. Penning trap mass measurements and laser spectroscopy on neutron-rich fission products extracted from the research reactor TRIGA-Mainz

    Energy Technology Data Exchange (ETDEWEB)

    Eibach, Martin; Ketelaer, Jens; Ketter, Jochen; Knuth, Konstantin [Institut fuer Physik, Universitaet Mainz (Germany); Blaum, Klaus; Nagy, Szilard [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Eberhardt, Klaus; Noertershaeuser, Wilfried [Institut fuer Kernchemie, Universitaet Mainz (Germany); Herfurth, Frank [GSI, Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Smorra, Christian [Physikalisches Institut, Universitaet Heidelberg (Germany); Institut fuer Kernchemie, Universitaet Mainz (Germany)

    2009-07-01

    TRIGA-SPEC is a setup for Penning trap mass spectrometry and collinear laser spectroscopy on short-lived neutron-rich nuclides located at the research reactor TRIGA-Mainz. It is dedicated to the determination of nuclear ground-state properties like masses and charge-radii. The nuclides are produced by neutron-induced fission of an actinide target located in a target chamber near the reactor core. It is required to extract the nuclides fast and with high efficiency from the target chamber in order to make precision experiments on short-living species with half-lives in the order of 1s. To this end, they are flushed out with a helium gas jet containing carbon aerosols and transported through a skimmer region to an ECR ion source. The characterisation of the carbon aerosol generator and the verification of transported fission products are presented.

  11. Screening and characterization of reactive compounds with in vitro peptide-trapping and liquid chromatography/high-resolution accurate mass spectrometry.

    Science.gov (United States)

    Wei, Cong; Chupak, Louis S; Philip, Thomas; Johnson, Benjamin M; Gentles, Robert; Drexler, Dieter M

    2014-02-01

    The present study describes a novel methodology for the detection of reactive compounds using in vitro peptide-trapping and liquid chromatography-high-resolution accurate mass spectrometry (LC-HRMS). Compounds that contain electrophilic groups can covalently bind to nucleophilic moieties in proteins and form adducts. Such adducts are thought to be associated with drug-mediated toxicity and therefore represent potential liabilities in drug discovery programs. In addition, reactive compounds identified in biological screening can be associated with data that can be misinterpreted if the reactive nature of the compound is not appreciated. In this work, to facilitate the triage of hits from high-throughput screening (HTS), a novel assay was developed to monitor the formation of covalent peptide adducts by compounds suspected to be chemically reactive. The assay consists of in vitro incubations of test compounds (under conditions of physiological pH) with synthetically prepared peptides presenting a variety of nucleophilic moieties such as cysteine, lysine, histidine, arginine, serine, and tyrosine. Reaction mixtures were analyzed using full-scan LC-HRMS, the data were interrogated using postacquisition data mining, and modified amino acids were identified by subsequent LC-HRMS/mass spectrometry. The study demonstrated that in vitro nucleophilic peptide trapping followed by LC-HRMS analysis is a useful approach for screening of intrinsically reactive compounds identified from HTS exercises, which are then removed from follow-up processes, thus obviating the generation of data from biochemical activity assays.

  12. Inelastic scattering of light by a cold trapped atom: Effects of the quantum center-of-mass motion

    CERN Document Server

    Bienert, M; Morigi, G; Bienert, Marc; Merkel, Wolfgang; Morigi, Giovanna

    2005-01-01

    The light scattered by a cold trapped ion, which is in the stationary state of laser cooling, presents features due to the mechanical effects of atom-photon interaction. These features appear as additional peaks (sidebands) in the spectrum of resonance fluorescence. Among these sidebands the literature has discussed the Stokes and anti-Stokes components, namely the sidebands of the elastic peak. In this manuscript we show that the motion also gives rise to sidebands of the inelastic peaks. These are not always visible, but, as we show, can be measured in parameter regimes which are experimentally accessible.

  13. Trapping radioactive ions

    CERN Document Server

    Kluge, Heinz-Jürgen

    2004-01-01

    Trapping devices for atomic and nuclear physics experiments with radioactive ions are becoming more and more important at accelerator facilities. While about ten years ago only one online Penning trap experiment existed, namely ISOLTRAP at ISOLDE/CERN, meanwhile almost every radioactive beam facility has installed or plans an ion trap setup. This article gives an overview on ion traps in the operation, construction or planing phase which will be used for fundamental studies with short-lived radioactive nuclides such as mass spectrometry, laser spectroscopy and nuclear decay spectroscopy. In addition, this article summarizes the use of gas cells and radiofrequency quadrupole (Paul) traps at different facilities as a versatile tool for ion beam manipulation like retardation, cooling, bunching, and cleaning.

  14. A volatile organic analyzer for Space Station: Description and evaluation of a gas chromatography/ ion mobility

    Science.gov (United States)

    Limero, Thomas F.; James, John T.

    1994-01-01

    A Volatile Organic Analyzer (VOA) is being developed as an essential component of the Space Station's Environmental Health System (EHS) air quality monitoring strategy to provide warning to the crew and ground personnel if volatile organic compounds exceed established exposure limits. The short duration of most Shuttle flights and the relative simplicity of the contaminant removal mechanism have lessened the concern about crew exposure to air contaminants on the Shuttle. However, the longer missions associated with the Space Station, the complex air revitalization system and the proposed number of experiments have led to a desire for real-time monitoring of the contaminants in the Space Station atmosphere. Achieving the performance requirements established for the VOA within the Space Station resource (e.g., power, weight) allocations led to a novel approach that joined a gas chromatograph (GC) to an ion mobility spectrometer (IMS). The authors of this paper will discuss the rational for selecting the GC/IMS technology as opposed to the more established gas chromatography/mass spectrometry (GC/MS) for the foundation of the VOA. The data presented from preliminary evaluations will demonstrate the versatile capability of the GC/IMS to analyze the major contaminants expected in the Space Station atmosphere. The favorable GC/IMS characteristics illustrated in this paper included excellent sensitivity, dual-mode operation for selective detection, and mobility drift times to distinguish co-eluting GC peaks. Preliminary studies have shown that the GC/IMS technology can meet surpass the performance requirements of the Space Station VOA.

  15. Liquid Chromatography-Electrospray Quadrupole Linear Ion Trap Mass Spectrometric Method for Quantitation of Domperidone in Chinese Healthy Volunteers

    Institute of Scientific and Technical Information of China (English)

    WU Yi; CHU Yang; ZHANG Yun-hui; WU Dan; GU Jing-kai

    2007-01-01

    A rapid, sensitive, and accurate method based on LC/MS/MS was developed and validated for the determination of domperidone in human plasma. Domperidone and internal standard, tramadol, were extracted from plasma with diethyl ether-dichloromethane(60: 40, volume ratio) and separated by reversed-phase HPLC with methanol-water-ammonia solution(80: 20: 0.2, volume ratio) as the mobile phase. Detection was carried out via multiple-reaction monitoring(MRM) on a Q-trapTM LC/MS/MS system(Q-trapTM). The assay result was linear over a concentration range of 0.1-30 ng/mL with a limit of quantitation (LOQ) of 0.1 ng/mL. The inter- and intra-day precision levels were within 7.52% and 12. 9%, respectively, whereas the accuracy was within a range of 87. 3%-114%. This method has been successfully applied to evaluate the pharmacokinetics of domperidone in Chinese healthy volunteers given an oral dose of 10 mg.

  16. [Screening and confirmation of 24 hormones in cosmetics by ultra high performance liquid chromatography-linear ion trap/orbitrap high resolution mass spectrometry].

    Science.gov (United States)

    Li, Zhaoyong; Wang, Fengmei; Niu, Zengyuan; Luo, Xin; Zhang, Gang; Chen, Junhui

    2014-05-01

    A method of ultra high performance liquid chromatography-linear ion trap/orbitrap high resolution mass spectrometry (UPLC-LTQ/Orbitrap MS) was established to screen and confirm 24 hormones in cosmetics. Various cosmetic samples were extracted with methanol. The extract was loaded onto a Waters ACQUITY UPLC BEH C18 column (50 mm x 2.1 mm, 1.7 microm) using a gradient elution of acetonitrile/water containing 0.1% (v/v) formic acid for the separation. The accurate mass of quasi-molecular ion was acquired by full scanning of electrostatic field orbitrap. The rapid screening was carried out by the accurate mass of quasi-molecular ion. The confirmation analysis for targeted compounds was performed with the retention time and qualitative fragments obtained by data dependent scan mode. Under the optimal conditions, the 24 hormones were routinely detected with mass accuracy error below 3 x 10(-6) (3 ppm), and good linearities were obtained in their respective linear ranges with correlation coefficients higher than 0.99. The LODs (S/N = 3) of the 24 compounds were hormones in 50 cosmetic samples. The results demonstrate that the method is a useful tool for the rapid screening and identification of the hormones in cosmetics.

  17. Quantification of urinary o,o'-dityrosine, a biomarker for oxidative damage to proteins, by high performance liquid chromatography with triple quadrupole tandem mass spectrometry. A comparison with ion-trap tandem mass spectrometry.

    Science.gov (United States)

    Orhan, Hilmi; Coolen, Stefan; Meerman, John H N

    2005-11-15

    We recently described an isotope dilution reversed-phase liquid chromatography-atmospheric pressure chemical ionization-ion-trap-tandem mass spectrometry (HPLC-APCI-MS/MS) method for the quantitative determination of oxidized amino acids in human urine, including o,o'-dityrosine, a specific marker of protein oxidation. In the present study, we investigated the possibility to use a triple quadrupole instrument for the analysis of this biomarker in urine. The two instruments were compared in terms of sensitivity, specificity and reproducibility. Results showed that the triple quadrupole instrument reaches 2.5-fold higher sensitivity (LOD=0.01 microM) compared to the previously used ion-trap instrument. Precision of the present assay is as follows: in-day variation is 4.6% and inter-day variation is 17%. The currently developed method was applied to a group of smoker urine samples. The mean urinary o,o'-dityrosine concentration was 0.08+/-0.01 microM. Expressed per urinary creatinine concentration, this corresponds to 10.1+/-0.4 micromol/mol creatinine. This is comparable to the previously reported values of 5.8+/-0.3 micromol/mol creatinine in non-smokers night-time urines, and 12.3+/-5 micromol/mol creatinine in day-time urines measured by the ion-trap instrument.

  18. Simultaneous determination of eight common odors in natural water body using automatic purge and trap coupled to gas chromatography with mass spectrometry.

    Science.gov (United States)

    Deng, Xuwei; Liang, Gaodao; Chen, Jun; Qi, Min; Xie, Ping

    2011-06-17

    Production and fate of taste and odor (T&O) compounds in natural waters are a pressing environmental issue. Simultaneous determination of these complex compounds (covering a wide range of boiling points) has been difficult. A simple and sensitive method for the determination of eight malodors products of cyanobacterial blooms was developed using automatic purge and trap (P&T) coupled with gas chromatography-mass spectrometry (GC-MS). This extraction and concentration technique is solvent-free. Dimethylsulfide (DMS), dimethyltrisulfide (DMTS), 2-isopropyl-3-methoxypyrazine (IPMP), 2-isobutyl-3-methoxypyrazine (IBMP), 2-methylisoborneol (MIB), β-cyclocitral, geosmin (GSM) and β-ionone were separated within 15.3 min. P&T uses trap #07 and high-purity nitrogen purge gas. The calibration curves of the eight odors show good linearity in the range of 1-500 ng/L with a correlation coefficient above 0.999 (levels=8) and with residuals ranging from approximately 83% to 124%. The limits of detection (LOD) (S/N=3) are all below 1.5 ng/L that of GSM is even lower at 0.08 ng/L. The relative standard deviations (RSD) are between 3.38% and 8.59% (n=5) and recoveries of the analytes from water samples of a eutrophic lake are between 80.54% and 114.91%. This method could be widely employed for monitoring these eight odors in natural waters.

  19. Rapid quantification of four major bioactive alkaloids in Corydalis decumbens (Thunb.) Pers. by pressurised liquid extraction combined with liquid chromatography-triple quadrupole linear ion trap mass spectrometry.

    Science.gov (United States)

    Shen, Yan; Han, Chao; Jiang, Yongxiang; Zhou, Xiujin; Zhu, Zhenou; Lei, Xinxiang

    2011-05-30

    A new method based on pressurised liquid extraction (PLE) followed by liquid chromatography-triple quadrupole linear ion trap mass spectrometry (LC-QTrap-MS) analysis has been developed for the identification and quantification of four major alkaloids in extracts of Corydalis decumbens (Thunb.) Pers. PLE extractions were performed using 90% ethanol; temperature was set at 100°C and pressure at 1500 psi. HPLC analysis was performed on a Waters XBridge™ C(18) column (150 mm × 2.1mm i.d., 3.5 μm) eluted by a mobile phase of acetonitrile and 0.2% acetic acid. Data acquisition was carried out in multiple reaction monitoring transitions (MRMs) mode, monitoring two MRM transitions to ensure an accurate identification of target compounds in the samples. Additional identification and confirmation of target compounds were performed using the enhanced product ion modus (EPI) of the linear ion trap. The novel LC-QTrap-MS platform offers the best sensitivity and specificity for characterization and quantitative determination of the four alkaloids in C. decumbens (Thunb.) Pers. and fulfils the quality criteria for routine laboratory application.

  20. Determination of 19 volatile organic compounds in wastewater effluents from different treatments by purge and trap followed by gas-chromatography coupled to mass spectrometry.

    Science.gov (United States)

    Barco-Bonilla, Nieves; Plaza-Bolaños, Patricia; Fernández-Moreno, José Luis; Romero-González, Roberto; Frenich, Antonia Garrido; Vidal, José Luis Martínez

    2011-07-01

    A rapid and simple methodology based on purge and trap with gas-chromatography coupled to triple quadrupole mass spectrometry has been developed for the analysis of 19 volatile organic compounds (VOCs) in wastewater (WW) effluents from four different treatments. The determination was carried out in the raw WW effluents, which were not submitted to any pre-treatment (e.g., filtration). A matrix effect study was also performed, concluding that solvent calibration was adequate to quantify VOCs in WW effluent samples containing a variety of suspended particulate matter. Adequate validation parameters were obtained with recovery values in the range 73-124% and precision values lower than 24%. Limits of quantification were established at 0.1 μg L(-1) for all VOCs. The proposed method was applied to the analysis of WW samples, detecting chloroform and toluene at concentrations ranging from 0.1 to 4.80 μg L(-1).

  1. Qualitative analysis of major constituents from Xue Fu Zhu Yu Decoction using ultra high performance liquid chromatography with hybrid ion trap time-of-flight mass spectrometry.

    Science.gov (United States)

    Fu, Chunyan; Xia, Zian; Liu, Yonghui; Lu, Hongmei; Zhang, Zhimin; Wang, Yang; Fan, Xiaqiong

    2016-09-01

    Xue Fu Zhu Yu Decoction, a famous formula that has been used for treating many blood stasis-caused diseases for many centuries, comprises 11 kinds of traditional Chinese medicines. A convenient, efficient, and rapid analytical method was developed to simultaneously determine the major compounds in this decoction. An ultra-high performance liquid chromatography with hybrid ion trap time-of-flight mass spectrometry method was used to rapidly separate and detect the major constituents of the decoction. Using this technique, we identified or tentatively identified 34 compounds, including 21 flavonoids, 5 terpenoids, 3 organic acids, 2 lactones, 1 alkaloid, 1 amino acid, and 1 cyanogenic glycoside. The MS analysis of these constituents was described in detail. Findings may contribute to future metabolic and pharmacokinetic studies of this medicine.

  2. Extraction and Analysis of Disperse Dyes from Colored Polyester Single Fibers Using Liquid Chromatography/Linear Ion Trap Tandem Mass Spectrometry.

    Science.gov (United States)

    Kato, Takao; Suzuki, Yasuhiro; Handa, Makoto

    2016-01-01

    Nine disperse dyes extracted from colored polyester threads and single fibers of manufactory-supplied textiles by using centrifugal filtration were analyzed using liquid chromatography/linear ion trap tandem mass spectrometry (LC/LIT-MS(n)). Based on diode array detector data, dimethylformamide (DMF) was found to be a more effective extraction solvent than acetonitrile/water (4:3, v/v) or methanol/water (1:1, v/v) mixtures. The precursor, [M+H](+) ions, were detected for the dyes extracted using DMF. The MS(2) and MS(3) spectra also matched those of the standard disperse dyes. Without relying on comparison clothes, disperse dyes extracted from the single fibers (5 mm in length) were successfully identified by LC/LIT-MS(n) and the custom-built database.

  3. Electrospray Ionization/Ion Mobility Spectrometer/Cylindrical Ion Trap Mass Spectrometer System for In-Situ Detection of Organic Compounds

    Science.gov (United States)

    Kanik, I.; Johnson, P. V.; Beegle, L. W.; Cooks, R. G.; Laughlin, B. C.; Hill, H. H.

    2003-01-01

    The potential of an Electrospray Ionization/Ion Mobility Spectrometer/Cylindrical Ion Trap Mass Spectrometer (ESI/IMS/CIT-MS) as an analytical instrument for analyzing material extracted from rock and soil samples as part of a suite of instruments on the proposed 2009 Mars Science Lander (MSL) will be demonstrated. This instrument will be able to identify volatile compounds as well as resident organic molecules on the parts-per-billion (ppb) level. Also, it will be able to obtain an inventory of chemical species on the surface of Mars which will result in a better understanding of ongoing surface chemistry. Finally, questions relevant to biological processes will be answered with the complete inventory of surface and near surface organic molecules that the ESI/IMS/CIT is capable of performing.

  4. Constructing and Using a Light Trap Harvester: Rural Technology for Mass Collection of Agoro Termites (Macrotermes subhylanus

    Directory of Open Access Journals (Sweden)

    M.A. Ayieko

    2011-02-01

    Full Text Available Entomophagy is now a growing industry in many parts of the world especially in the developing countries. Entrepreneurs in several parts of the world are making edible insects both palatable and marketable for income generation. The traditional use of insects as food continues to be widespread in tropical and subtropical countries and to provide significant nutritional, economic and ecological benefits for rural communities. Consumption of insects is considered to be a more efficient use of the world's resources to feed the growing population. Insect consumption is growing in many parts of the world and the winged termite in particular is consumed widely in various part of East Africa especially in the western part of Kenya. The traditional methods of collecting these termites vary considerably from one region to another. This paper highlights the indigenous ways of collecting Macrotermes subhylanus locally known as Agoro in the Lake Victoria region. The method was developed by integrating modern technology and the indigenous technological knowledge. The variation in the yield of the sample of Agoro mounds selected and the traps used are presented and discussed.

  5. Penning-trap mass measurements of exotic rubidium and gold isotopes for a mean-field study of pairing and quadrupole correlations

    CERN Document Server

    Manea, Vladimir

    2015-09-14

    The most complex nuclei are situated between the magic and the mid-shell ones, in regions known for sudden changes of the trends of nuclear observables. These are the so-called shape-transition regions, where the nuclear paradigm changes from the vibrational liquid drop to the static rotor. With few exceptions, nuclei in these regions are radioactive, with half-lives dropping into the millisecond range. Complementing the information obtained from the low-lying excitation spectrum, nuclear binding energies and mean-square charge radii are among the observables most sensitive to these changes of nuclear structure. In the present work, a study of the shape- transition phenomenon is performed by measurements of radioactive nuclides produced by the ISOLDE facility at CERN. The masses of the neutron-rich rubidium isotopes $^{98-100}$Rb and of the neutron-deficient gold isotopes $^{180, 185, 188, 190, 191}$Au are determined using the Penning-trap mass spectrometer ISOLTRAP. The mass of $^{100}$Rb is determined for t...

  6. Negative chemiions formed in jet fuel combustion: new insights from jet engine and laboratory measurements using a quadrupole ion trap mass spectrometer apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Kiendler, A.; Aberle, S.; Arnold, F. [Max Planck Institute for Nuclaear Physics, Heidelberg (Germany). Atmospheric Physics Div.

    2000-07-01

    Measurements were made of mass numbers and composition of negative chemiions produced in jet fuel combustion in the exhaust of a jet engine and of a burner in the laboratory. The measurements made by a novel quadrupole ion trap mass spectrometer apparatus revealed the presence of three major ion families: ions containing an HSO{sub 4}{sup -} ''core's' or an NO{sub 3}{sup -} ''core's' and {sup O}HC-ions{sup .} The latter which contain C and H atoms and in part also 0 atoms can be divided into two subfamilies with even and odd mass numbers. It is proposed that the O HC ions are formed by free-electron attachment to HC and OHC molecules and/or ion-molecule reactions of primary negative chemiions with HC and OHC molecules. It is also proposed that HSO{sub 4}{sup -}- and NO{sub 3}{sup -}- containing ions are formed by ion-molecule reactions involving OHC ions and the sulfur- and reactive nitrogen-containing molecules H{sub 2}SO{sub 4}, SO{sub 3} and NO, NO{sub 2}, HNO{sub 2}, HNO{sub 3}. (author)

  7. Detection of gaseous compounds by needle trap sampling and direct thermal-desorption photoionization mass spectrometry: concept and demonstrative application to breath gas analysis.

    Science.gov (United States)

    Kleeblatt, Juliane; Schubert, Jochen K; Zimmermann, Ralf

    2015-02-01

    A fast detection method to analyze gaseous organic compounds in complex gas mixtures was developed, using a needle trap device (NTD) in conjunction with thermal-desorption photoionization time-of-flight mass spectrometry (TD-PI-TOFMS). The mass spectrometer was coupled via a deactivated fused silica capillary to an injector of a gas chromatograph. In the hot injector, the analytes collected on the NTD were thermally desorbed and directly transferred to the PI-TOFMS ion source. The molecules are softly ionized either by single photon ionization (SPI, 118 nm) or by resonance enhanced multiphoton ionization (REMPI, 266 nm), and the molecular ion signals are detected in the TOF mass analyzer. Analyte desorption and the subsequent PI-TOFMS detection step only lasts ten seconds. The specific selectivity of REMPI (i.e., aromatic compounds) and universal ionization characteristics render PI-MS as a promising detection system. As a first demonstrative application, the alveolar phase breath gas of healthy, nonsmoking subjects was sampled on NTDs. While smaller organic compounds such as acetone, acetaldehyde, isoprene, or cysteamine can be detected in the breath gas with SPI, REMPI depicts the aromatic substances phenol and indole at 266 nm. In the breath gas of a healthy, smoking male subject, several xenobiotic substances such as benzene, toluene, styrene, and ethylbenzene can be found as well. Furthermore, the NTD-REMPI-TOFMS setup was tested for breath gas taken from a mechanically ventilated pig under continuous intravenous propofol (2,6-diisopropylphenol, narcotic drug) infusion.

  8. Multiple and sequential data acquisition method: an improved method for fragmentation and detection of cross-linked peptides on a hybrid linear trap quadrupole Orbitrap Velos mass spectrometer.

    Science.gov (United States)

    Rudashevskaya, Elena L; Breitwieser, Florian P; Huber, Marie L; Colinge, Jacques; Müller, André C; Bennett, Keiryn L

    2013-02-05

    The identification and validation of cross-linked peptides by mass spectrometry remains a daunting challenge for protein-protein cross-linking approaches when investigating protein interactions. This includes the fragmentation of cross-linked peptides in the mass spectrometer per se and following database searching, the matching of the molecular masses of the fragment ions to the correct cross-linked peptides. The hybrid linear trap quadrupole (LTQ) Orbitrap Velos combines the speed of the tandem mass spectrometry (MS/MS) duty circle with high mass accuracy, and these features were utilized in the current study to substantially improve the confidence in the identification of cross-linked peptides. An MS/MS method termed multiple and sequential data acquisition method (MSDAM) was developed. Preliminary optimization of the MS/MS settings was performed with a synthetic peptide (TP1) cross-linked with bis[sulfosuccinimidyl] suberate (BS(3)). On the basis of these results, MSDAM was created and assessed on the BS(3)-cross-linked bovine serum albumin (BSA) homodimer. MSDAM applies a series of multiple sequential fragmentation events with a range of different normalized collision energies (NCE) to the same precursor ion. The combination of a series of NCE enabled a considerable improvement in the quality of the fragmentation spectra for cross-linked peptides, and ultimately aided in the identification of the sequences of the cross-linked peptides. Concurrently, MSDAM provides confirmatory evidence from the formation of reporter ions fragments, which reduces the false positive rate of incorrectly assigned cross-linked peptides.

  9. Obesity induced by high dietary fat leads to increased bone resorption marker, TRAP, and decreased bone mass in mice

    Science.gov (United States)

    Obesity, which is growing in prevalence, is a risk factor for such chronic health disorders as diabetes and cardiovascular diseases. However, it is thought to be a protective factor for osteoporosis and bone fractures in humans. Accumulating data in humans suggest that fat mass has a negative effect...

  10. Characterization of phthiocerol and phthiodiolone dimycocerosate esters of M. tuberculosis by multiple-stage linear ion-trap mass spectrometry

    NARCIS (Netherlands)

    Flentie, Kelly N; Stallings, Christina L; Turk, John; Minnaard, Adriaan J; Hsu, Fong-Fu

    2015-01-01

    Both phthiocerol/phthiodiolone dimycocerosate (PDIM) and phenolic glycolipids (PGL) are abundant virulent lipids in the cell wall of various pathogenic mycobacteria, which can synthesize a wide range of complex high molecular weight lipids. In this report, we describe LIT MSn mass spectrometric appr

  11. Quantitation of isobaric phosphatidylcholine species in human plasma using a hybrid quadrupole linear ion trap mass spectrometer

    Science.gov (United States)

    Phosphatidylcholine (PC) species in human plasma are used as biomarkers of disease. PC biomarkers are often limited by the inability to separate isobaric PC. In this work, we developed a targeted shotgun approach for analysis of isobaric and isomeric PC. This approach is comprised of two mass spectr...

  12. Evaluation and application of static headspace-multicapillary column-gas chromatography-ion mobility spectrometry for complex sample analysis.

    Science.gov (United States)

    Denawaka, Chamila J; Fowlis, Ian A; Dean, John R

    2014-04-18

    An evaluation of static headspace-multicapillary column-gas chromatography-ion mobility spectrometry (SHS-MCC-GC-IMS) has been undertaken to assess its applicability for the determination of 32 volatile compounds (VCs). The key experimental variables of sample incubation time and temperature have been evaluated alongside the MCC-GC variables of column polarity, syringe temperature, injection temperature, injection volume, column temperature and carrier gas flow rate coupled with the IMS variables of temperature and drift gas flow rate. This evaluation resulted in six sets of experimental variables being required to separate the 32 VCs. The optimum experimental variables for SHS-MCC-GC-IMS, the retention time and drift time operating parameters were determined; to normalise the operating parameters, the relative drift time and normalised reduced ion mobility for each VC were determined. In addition, a full theoretical explanation is provided on the formation of the monomer, dimer and trimer of a VC. The optimum operating condition for each VC calibration data was obtained alongside limit of detection (LOD) and limit of quantitation (LOQ) values. Typical detection limits ranged from 0.1ng bis(methylthio)methane, ethylbutanoate and (E)-2-nonenal to 472ng isovaleric acid with correlation coefficient (R(2)) data ranging from 0.9793 (for the dimer of octanal) through to 0.9990 (for isobutyric acid). Finally, the developed protocols were applied to the analysis of malodour in sock samples. Initial work involved spiking an inert matrix and sock samples with appropriate concentrations of eight VCs. The average recovery from the inert matrix was 101±18% (n=8), while recoveries from the sock samples were lower, that is, 54±30% (n=8) for sock type 1 and 78±24% (n=6) for sock type 2. Finally, SHS-MCC-GC-IMS was applied to sock malodour in a field trial based on 11 volunteers (mixed gender) over a 3-week period. By applying the SHS-MCC-GC-IMS database, four VCs were

  13. Fragmentation energy index for universalization of fragmentation energy in ion trap mass spectrometers for the analysis of chemical weapon convention related chemicals by atmospheric pressure ionization-tandem mass spectrometry analysis.

    Science.gov (United States)

    Palit, Meehir; Mallard, Gary

    2009-04-01

    The use of mass spectra generated at 70 eV in electron ionization (EI) as a universal standard for EI has helped in the generation of searchable library databases and had a profound influence on the analytical applications of gas chromatography/mass spectrometry (GC/MS), similarly for liquid chromatography tandem mass spectrometry (LC-MS/MS), suggesting a novel method to normalize the collisional energy for the universalization of fragmentation energy for the analysis of Chemical Weapon Convention (CWC)-related chemicals by atmospheric pressure ionization-tandem mass spectrometry (API-MS(n)) using three-dimensional (3D) ion trap instruments. For normalizing fragmentation energy a "fragmentation energy index" (FEI) is proposed which is an arbitrary scale based on the fact of specific MS/MS fragmentation obtained at different collisional energies for the reference chemicals which are not CWC scheduled compounds. FEI 6 for the generation of an MS(n) library-searchable mass spectral database is recommended.

  14. A comprehensive library-based, automated screening procedure for 46 synthetic cannabinoids in serum employing liquid chromatography-quadrupole ion trap mass spectrometry with high-temperature electrospray ionization.

    Science.gov (United States)

    Huppertz, Laura M; Kneisel, Stefan; Auwärter, Volker; Kempf, Jürgen

    2014-02-01

    Considering the vast variety of synthetic cannabinoids and herbal mixtures - commonly known as 'Spice' or 'K2' - on the market and the resulting increase of severe intoxications related to their consumption, there is a need in clinical and forensic toxicology for comprehensive up-to-date screening methods. The focus of this project aimed at developing and implementing an automated screening procedure for the detection of synthetic cannabinoids in serum using a liquid chromatography-ion trap-MS (LC-MS(n)) system and a spectra library-based approach, currently including 46 synthetic cannabinoids and 8 isotope labelled analogues. In the process of method development, a high-temperature ESI source (IonBooster(TM), Bruker Daltonik) and its effects on the ionization efficiency of the investigated synthetic cannabinoids were evaluated and compared to a conventional ESI source. Despite their structural diversity, all investigated synthetic cannabinoids benefitted from high-temperature ionization by showing remarkably higher MS intensities compared to conventional ESI. The employed search algorithm matches retention time, MS and MS(2)/MS(3) spectra. With the utilization of the ionBooster source, limits for the automated detection comparable to cut-off values of routine MRM methods were achieved for the majority of analytes. Even compounds not identified when using a conventional ESI source were detected using the ionBooster-source. LODs in serum range from 0.1 ng/ml to 0.5 ng/ml. The use of parent compounds as analytical targets offers the possibility of instantly adding new emerging compounds to the library and immediately applying the updated method to serum samples, allowing the rapid adaptation of the screening method to ongoing forensic or clinical requirements. The presented approach can also be applied to other specimens, such as oral fluid or hair, and herbal mixtures and was successfully applied to authentic serum samples. Quantitative MRM results of samples with

  15. Inequalities Between Size, Mass, Angular Momentum, and Charge for Axisymmetric Bodies and the Formation of Trapped Surfaces

    CERN Document Server

    Khuri, Marcus

    2016-01-01

    We establish inequalities relating the size of a material body to its mass, angular momentum, and charge, within the context of axisymmetric initial data sets for the Einstein equations. These inequalities hold in general without the assumption of the maximal condition, and use a notion of size which is easily computable. Moreover, these results give rise to black hole existence criteria which are meaningful even in the time-symmetric case, and also include certain boundary effects.

  16. Metabolism of olaquindox in rat liver microsomes: structural elucidation of metabolites by high-performance liquid chromatography combined with ion trap/time-of-flight mass spectrometry.

    Science.gov (United States)

    Liu, Zhaoying; Huang, Lingli; Dai, Menghong; Chen, Dongmei; Wang, Yulian; Tao, Yanfei; Yuan, Zonghui

    2008-04-01

    Olaquindox (N-(2-hydroxyethyl)-3-methyl-2-quinoxalincarboxamide-1,4-dioxide) is a growth-promoting feed additive for food-producing animals. Its toxicity is closely related to the metabolism. The complete metabolic pathways of olaquindox are not revealed. To improve studies of the metabolism and toxicity of olaquindox, its biotransformation in rat liver microsomes and the structure of its metabolites using high-performance liquid chromatography combined with ion trap/time-of-flight mass spectrometry (LC/MS-ITTOF) were investigated. When olaquindox was incubated with an NADPH-generating system and rat liver microsomes, ten metabolites (M1-M10) were detected. The structures of these metabolites were identified from mass spectra and comparison of their changes in their accurate molecular masses and fragment ions with those of the parent drug. With the high resolution and good mass accuracy achieved by this technique, the elemental compositions of the metabolites and their fragment ions were exactly determined. The results indicate that the N --> O group reduction is the main metabolic pathway of olaquindox metabolism in rat liver microsomes, because abundant 1-desolaquindox (M2), 4-desolaquindox (M1) and bisdesoxyolaquindox (M9) were produced during the incubation step. Seven other minor metabolites were revealed which were considered to be hydroxylation metabolites, based on the position of the quinoxaline ring or 3-methyl group and a carboxylic acid derivative on the side chain at position 2 of the quinoxaline ring. Among the identified metabolites, five new hydroxylated metabolites (M3-M7) were found for the first time in rat liver microsomes. This work will conduce to complete clarification of olaquindox metabolism, and improve the in vivo metabolism of olaquindox in food animals.

  17. [Screening and confirmation of carcinogenic dyes in textiles by high performance liquid chromatography-linear ion trap/orbitrap high resolution mass spectrometry].

    Science.gov (United States)

    Xiu, Xiaoli; Luo, Xin; Niu, Zengyuan; Ye, Xiwen; Zhixu, Tang; Li, Jingying; Wang, Yongwei; Du, Wei

    2013-10-01

    A method of high performance liquid chromatography-linear ion trap/Orbitrap high resolution mass spectrometry (HPLC-LTQ/Orbitrap MS) was used to screen and confirm carcinogenic dyes in textiles. The analytes were extracted from textile samples with pyridine/water (1/1, v/v) in a water bath under controlled conditions (95 degrees C, 150 r/min), and then filtered with a 0.22 microm polytetrafluoroetylene (PTFE) membrane. The eluates were separated on a CAPCELL PAK C18 column (100 mm x 2.0 mm, 5 microm) using gradient elution with acetonitrile/ 5 mmol/L ammonium acetate aqueous solution containing 0.01% formic acid (in positive mode) and acetonitrile/5 mmol/L ammonium acetate aqueous solution (in negative mode), and finally detected by HPLC-LTQ/Orbitrap MS in ESI modes. Full scan experiments were performed over the range of m/z 200-800. The screening and quantitative analysis were carried out by the accurate mass of quasi-molecular ion and the peak area in extracted chromatogram with accurate mass, respectively. The confirmatory analysis for target compounds was performed with the retention time and qualitative fragments obtained by data-dependent scan mode. Under the optimal conditions, nine carcinogenic dyes were routinely detected with mass accuracy below 5 x 10(-6) (5 ppm), and good linearities were provided in their respective linear ranges with correlation coefficients higher than 0.99. The limits of detection were in the range of 0.125-25 mg/kg. The average recoveries at three spiked levels were in the range of 62.13%116.28% with the relative standard deviations (RSDs) lower than 15%. The proposed method was applied to screen and confirm the nine carcinogenic dyes in textile samples. It is convenient and reliable.

  18. Selenium metabolomics in yeast using complementary reversed-phase/hydrophilic ion interaction (HILIC) liquid chromatography-electrospray hybrid quadrupole trap/Orbitrap mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Arnaudguilhem, C.; Bierla, K.; Ouerdane, L.; Preud' homme, H. [CNRS/UPPA, Laboratoire de Chimie Analytique Bio-inorganique et Environnement, UMR 5254, Helioparc, 2, Av. Pr. Angot, 64053 Pau (France); Yiannikouris, A. [Alltech Inc., 3031 Catnip Hill Pike, Nicholasville, KY (United States); Lobinski, R., E-mail: ryszard.lobinski@univ-pau.fr [CNRS/UPPA, Laboratoire de Chimie Analytique Bio-inorganique et Environnement, UMR 5254, Helioparc, 2, Av. Pr. Angot, 64053 Pau (France); Chair of Analytical Chemistry, Warsaw University of Technology, 00-664 Warszawa (Poland)

    2012-12-13

    Highlights: Black-Right-Pointing-Pointer The use of bimodal chromatographic separation enlarged amount of compounds identified. Black-Right-Pointing-Pointer The method allowed the largest scale ever (>60 compounds) speciation analysis of selenium metabolites in Se-rich yeast. Black-Right-Pointing-Pointer The estimated concentration of compounds was given. - Abstract: A high efficiency chromatographic separation on a porous graphitic carbon stationary phase was developed for a large-scale separation of selenium metabolites in Se-rich yeast prior to their identification by electrospray hybrid quadrupole trap/Orbitrap mass spectrometry (Orbitrap MS{sup n}). The reversed-phase (RP) separation mode offered distinctly higher separation efficiency than the hydrophilic ion interaction (HILIC) mode. The latter was nevertheless complementary and useful to validate the detection of several compounds. The method allowed the detection of 64 metabolites including 30 Se-Se or Se-S conjugates (3 triple S/Se/S ones) and 14 selenoethers. 21 previously unreported metabolites were detected on the basis of the selenium isotopic pattern usually matched with the sub-ppm mass accuracy. 9 of these metabolites were subsequently identified using the multi-stage high mass accuracy (<5 ppm) mass spectrometry. The identified metabolites (and their groups) were quantified on-line by ICP-MS fitted with a frequency-matching generator allowing a quasi-uniform response over the large (20-90%) acetonitrile mobile phase concentration range. The morphology of HPLC-ICP-MS chromatograms was remarkably similar to that of HPLC multi-ion extracted ESI-MS chromatograms. The detection limits obtained by ICP MS and ESI MS were 1 and 2 ppb, respectively.

  19. Performance of the Linear Ion Trap Mass Spectrometer for the Mars Organic Molecule Analyzer (MOMA) Investigation on the 2018 Exomars Rover

    Science.gov (United States)

    Arevalo, Ricardo, Jr.; Brinckerhoff, William B.; Pinnick, Veronica T.; van Amerom, Friso H. W.; Danell, Ryan M.; Li, Xiang; Getty, Stephanie; Hovmand, Lars; Atanassova, Martina; Mahaffy, Paul R.; Chu, Zhiping; Goesmann, Fred; Steininger, Harald

    2014-01-01

    The 2018 ExoMars rover mission includes the Mars Organic Molecule Analyzer (MOMA) investigation. MOMA will examine the chemical composition of samples acquired from depths of up to two meters below the martian surface, where organics may be protected from degradation derived from cosmic radiation and/or oxidative chemical reactions. When combined with the complement of instruments in the rover's Pasteur Payload, MOMA has the potential to reveal the presence of a wide range of organics preserved in a variety of mineralogical environments, and to begin to understand the structural character and potential origin of those compounds. The MOMA investigation is led by the Max Planck Institute for Solar System Research (MPS) with the mass spectrometer subsystem provided by NASA GSFC. MOMA's linear ion trap mass spectrometer (ITMS) is designed to analyze molecular composition of: (i) gas evolved from pyrolyzed powder samples and separated in a gas chromatograph; and, (ii) ions directly desorbed from crushed solid samples at Mars ambient pressure, as enabled by a pulsed UV laser system, fast-actuating aperture valve and capillary ion inlet. Breadboard ITMS and associated electronics have been advanced to high end-to-end fidelity in preparation for flight hardware delivery to Germany in 2015.

  20. Direct and Sensitive Detection of CWA Simulants by Active Capillary Plasma Ionization Coupled to a Handheld Ion Trap Mass Spectrometer.

    Science.gov (United States)

    Wolf, Jan-Christoph; Etter, Raphael; Schaer, Martin; Siegenthaler, Peter; Zenobi, Renato

    2016-07-01

    An active capillary plasma ionization (ACI) source was coupled to a handheld mass spectrometer (Mini 10.5; Aston Labs, West Lafayette, IN, USA) and applied to the direct gas-phase detection and quantification of chemical warfare agent (CWA) related chemicals. Complementing the discontinuous atmospheric pressure interface (DAPI) of the Mini 10.5 mass spectrometer with an additional membrane pump, a quasi-continuous sample introduction through the ACI source was achieved. Nerve agent simulants (three dialkyl alkylphosphonates, a dialkyl phosporamidate, and the pesticide dichlorvos) were detected at low gas-phase concentrations with limits of detection ranging from 1.0 μg/m(3) to 6.3 μg/m(3). Our results demonstrate a sensitivity enhancement for portable MS-instrumentation by using an ACI source, enabling direct, quantitative measurements of volatile organic compounds. Due to its high sensitivity, selectivity, low power consumption (<80 W) and weight (<13 kg), this instrumentation has the potential for direct on-site CWA detection as required by military or civil protection. Graphical Abstract ᅟ.

  1. Direct and Sensitive Detection of CWA Simulants by Active Capillary Plasma Ionization Coupled to a Handheld Ion Trap Mass Spectrometer

    Science.gov (United States)

    Wolf, Jan-Christoph; Etter, Raphael; Schaer, Martin; Siegenthaler, Peter; Zenobi, Renato

    2016-07-01

    An active capillary plasma ionization (ACI) source was coupled to a handheld mass spectrometer (Mini 10.5; Aston Labs, West Lafayette, IN, USA) and applied to the direct gas-phase detection and quantification of chemical warfare agent (CWA) related chemicals. Complementing the discontinuous atmospheric pressure interface (DAPI) of the Mini 10.5 mass spectrometer with an additional membrane pump, a quasi-continuous sample introduction through the ACI source was achieved. Nerve agent simulants (three dialkyl alkylphosphonates, a dialkyl phosporamidate, and the pesticide dichlorvos) were detected at low gas-phase concentrations with limits of detection ranging from 1.0 μg/m3 to 6.3 μg/m3. Our results demonstrate a sensitivity enhancement for portable MS-instrumentation by using an ACI source, enabling direct, quantitative measurements of volatile organic compounds. Due to its high sensitivity, selectivity, low power consumption (<80 W) and weight (<13 kg), this instrumentation has the potential for direct on-site CWA detection as required by military or civil protection.

  2. Comprehensive profiling of N-acylhomoserine lactones produced by Yersinia pseudotuberculosis using liquid chromatography coupled to hybrid quadrupole-linear ion trap mass spectrometry.

    Science.gov (United States)

    Ortori, Catharine A; Atkinson, Steve; Chhabra, Siri Ram; Cámara, Miguel; Williams, Paul; Barrett, David A

    2007-01-01

    A method for the comprehensive profiling of the N-acylhomoserine lactone (AHL) family of bacterial quorum-sensing molecules is presented using liquid chromatography (LC) coupled to hybrid quadrupole-linear ion trap (QqQLIT) mass spectrometry. Information-dependent acquisition (IDA), using triggered combinations of triple-quadrupole and linear ion trap modes in the same LC-MS/MS run, was used to simultaneously screen, quantify and identify multiple AHLs in a single sample. This MS method uses common AHL fragment ions attributed to the homoserine moiety and the 3-oxo-, 3-hydroxy- or unsubstituted acyl side chains, to identify unknown AHLs in cell-free culture supernatants in an unbiased manner. This LC-MS technique was applied to determine the relative molar ratios of AHLs produced by Yersinia pseudotuberculosis and the consequences of inactivating by mutation either or both of the AHL synthase genes (ypsI and ytbI) on AHL profile and concentration. The Y. pseudotuberculosis wild type but not the ypsI ytbI double mutant produced at least 24 different AHLs with acyl chains ranging from C4 to C15 with or without 3-oxo or 3-hydroxy substituents. YtbI, in contrast to YpsI, could direct the synthesis of all of the AHLs identified. The most abundant and hence most biologically relevant Y. pseudotuberculosis AHLs were found to be the 3-oxo-substituted C6, C7 and C8 AHLs and the unsubstituted C6 and C8 compounds. The LC-QqQLIT methodology is broadly applicable to quorum-sensing signal molecule analysis and can provide comprehensive AHL profiles and concentrations from a single sample and simultaneously collect confirmatory spectra for each AHL identified.

  3. Stability studies of propoxur herbicide in environmental water samples by liquid chromatography-atmospheric pressure chemical ionization ion-trap mass spectrometry.

    Science.gov (United States)

    Sun, Lei; Lee, Hian Kee

    2003-10-01

    Liquid chromatography-atmospheric pressure ionization ion-trap mass spectrometry has been investigated for the analysis of polar pesticides in water. The degradation behavior of propoxur, selected as a model pesticide belonging to the N-methylcarbamate group, in various aqueous matrices (Milli-Q water, drinking water, rain water, seawater and river water) was investigated. Two interfaces of atmospheric pressure ionization, atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI), were compared during the study. Propoxur and its transformation product (N-methylformamide) were best ionized as positive ions with both APCI and ESI, while another transformation product (2-isopropoxyphenol) yielded stronger signals as negative ions only with APCI. In addition, the effects of various pH, matrix type and irradiation sources (sunlight, darkness, indoor lighting and artificial UV lamp) on the chemical degradation (hydrolysis) were also assessed. From the kinetic studies of degradation, it was found that the half-life of propoxur was reduced from 327 to 161 h in Milli-Q water with variation of irradiation conditions from dark to sunlight exposure. Degradation rates largely increased with increasing pH. The half-life of the target compound dissolved in Milli-Q water under darkness decreased from 407 to 3 h when the pH of Milli-Q water was increased from 5 to 8.5. These suggest that hydrolysis of propoxur is light-intensity and pH-dependent. In order to mimic contaminated natural environmental waters, propoxur was spiked into real water samples at 30 microg/l. The degradation of propoxur in such water samples under various conditions were studied in detail and compared. With the ion trap run in a time-scheduled single ion monitoring mode, typical limits of detection of the instrument were in the range of 1-10 microg/l.

  4. Liquid chromatography/negative electrospray ionization ion trap MS(2) mass spectrometry application for the determination of microcystins occurrence in Southern Portugal water reservoirs.

    Science.gov (United States)

    Rodrigues, M A; Reis, M P; Mateus, M C

    2013-11-01

    Microcystins (MCs) are toxins produced by cyanobacteria which are common organisms in the phytoplankton of eutrophic lakes, rivers and freshwater reservoirs. In the present work, a novel method of liquid chromatography-electrospray ion trap tandem mass spectrometry (LC/ESI/Ion trap-MS/MS), operated in the negative ionization mode, was developed for the analysis of these cyanotoxins. The method was applied to determine the amounts of total microcystins-LR, -YR and -RR in two water reservoirs in Southern Portugal, namely Alqueva and Beliche. A total of 30 water samples were analysed along 2011. Solid phase extraction (SPE) was used for sample cleaning-up and analyte enrichment. The extracted toxins were separated on a C18 column with a gradient of acetonitrile/water with 0.1% formic acid. Detection of microcystins was carried out using multiple reaction monitoring (MRM) in the negative polarity mode, as this method gave a higher selectivity. The MC-RR, YR and LR quantification limits were 17.9, 31.7 and 15.8 ng/L, respectively; quite below the limits recommended by WHO guidelines for drinking water (1 μg/L). Total MC highest concentrations were found in the warm months of June, July and September in Alqueva sampling sites, with concentrations of MC LR and RR ranging 17-344 and 25-212 ng/L, respectively, showing comparable results for MC-RR and LR and slightly lower concentration of MC-YR. Detected values for Beliche reservoir were below quantification limits.

  5. Suitability of magnetic particle immunoassay for the analysis of PBDEs in Hawaiian freshwater fish and crabs in comparison with gas chromatography/electron capture detection-ion trap mass spectrometry

    Science.gov (United States)

    A gas chromatograph/electron capture detector-ion trap mass spectrometer (GC/ECD-ITMS) was used for the determination of polybrominated diphenyl ethers (PBDEs) in freshwater fish and crabs. The samples were also analyzed with an enzyme-linked immunosorbent assay (ELISA). GC/ECD-ITMS results showed...

  6. Analysis of 19-nortestosterone residue in animal tissues by ion-trap gas chromatography-tandem mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    Jin-qing JIANG; Lei ZHANG; Guang-ling LI; Hai-tang ZHANG; Xue-feng YANG; Jun-wei LIU; Ren-feng LI; Zi-liang WANG; Jian-hua WANG

    2011-01-01

    A rapid sample treatment procedure for the gas chromatography-tandem mass spectrometry (GC-MS) determination of 19-nortestosterone (19-NT) in animal tissues has been developed. In our optimized procedures, enzymatic hydrolysis with p-glucuronidase from Escherichia coli was performed in an acetate buffer (pH 5.2,0.2 mol/L). Next, the homogenate was mixed with methanol and heated at 60 掳C for 15 min, then placed in an ice-bath at -18 掳C for 2 h. After liquid-liquid extraction with n-hexane, the analytes were subjected to a normal-phase solid phase extraction (SPE) C18 cartridge for clean-up. The dried organic extracts were derivatized with heptafluorobutyric anhydride (HFBA), and then the products were injected into GC-MS. Using electron impact mass spectrometry (EI-MS) with positive chemical ionization (PCI), four diagnostic ions (mlz 666, 453, 318, and 306) were determined. A standard calibration curve over the concentration range of 1-20 ng/g was reached, with Y=467084X-68354 (R2=0.9997) for 19-NT, and the detection limit was 0.3 ng. When applied to spiked samples collected from bovine and ovine, the recoveries ranged from 63% to 101% with relative standard deviation (RSD) between 2.7% and 8.9%. The procedure is a highly efficient, sensitive, and more economical method which offers considerable potential to resolve cases of suspected nandrolone doping in husbandry animals.

  7. Trapping ions with lasers

    CERN Document Server

    Cormick, Cecilia; Morigi, Giovanna

    2010-01-01

    This work theoretically addresses the trapping an ionized atom with a single valence electron by means of lasers, analyzing qualitatively and quantitatively the consequences of the net charge of the particle. In our model, the coupling between the ion and the electromagnetic field includes the charge monopole and the internal dipole, within a multipolar expansion of the interaction Hamiltonian. Specifically, we perform a Power-Zienau-Woolley transformation, taking into account the motion of the center of mass. The net charge produces a correction in the atomic dipole which is of order $m_e/M$ with $m_e$ the electron mass and $M$ the total mass of the ion. With respect to neutral atoms, there is also an extra coupling to the laser field which can be approximated by that of the monopole located at the position of the center of mass. These additional effects, however, are shown to be very small compared to the dominant dipolar trapping term.

  8. Rapid screening of drugs of abuse in human urine by high-performance liquid chromatography coupled with high resolution and high mass accuracy hybrid linear ion trap-Orbitrap mass spectrometry.

    Science.gov (United States)

    Li, Xiaowen; Shen, Baohua; Jiang, Zheng; Huang, Yi; Zhuo, Xianyi

    2013-08-09

    A novel analytical toxicology method has been developed for the analysis of drugs of abuse in human urine by using a high resolution and high mass accuracy hybrid linear ion trap-Orbitrap mass spectrometer (LTQ-Orbitrap-MS). This method allows for the detection of different drugs of abuse, including amphetamines, cocaine, opiate alkaloids, cannabinoids, hallucinogens and their metabolites. After solid-phase extraction with Oasis HLB cartridges, spiked urine samples were analysed by HPLC/LTQ-Orbitrap-MS using an electrospray interface in positive ionisation mode, with resolving power of 30,000 full width at half maximum (FWHM). Gradient elution off of a Hypersil Gold PFP column (50mm×2.1mm) allowed to resolve 65 target compounds and 3 internal standards in a total chromatographic run time of 20min. Validation of this method consisted of confirmation of identity, selectivity, linearity, limit of detection (LOD), lowest limits of quantification (LLOQ), accuracy, precision, extraction recovery and matrix effect. The regression coefficients (r(2)) for the calibration curves (LLOQ - 100ng/mL) in the study were ≥0.99. The LODs for 65 validated compounds were better than 5ng/ml except for 4 compounds. The relative standard deviation (RSD), which was used to estimate repeatability at three concentrations, was always less than 15%. The recovery of extraction and matrix effects were above 50 and 70%, respectively. Mass accuracy was always better than 2ppm, corresponding to a maximum mass error of 0.8 millimass units (mmu). The accurate masses of characteristic fragments were obtained by collisional experiments for a more reliable identification of the analytes. Automated data analysis and reporting were performed using ToxID software with an exact mass database. This procedure was then successfully applied to analyse drugs of abuse in a real urine sample from subject who was assumed to be drug addict.

  9. Microfabricated cylindrical ion trap

    Science.gov (United States)

    Blain, Matthew G.

    2005-03-22

    A microscale cylindrical ion trap, having an inner radius of order one micron, can be fabricated using surface micromachining techniques and materials known to the integrated circuits manufacturing and microelectromechanical systems industries. Micromachining methods enable batch fabrication, reduced manufacturing costs, dimensional and positional precision, and monolithic integration of massive arrays of ion traps with microscale ion generation and detection devices. Massive arraying enables the microscale cylindrical ion trap to retain the resolution, sensitivity, and mass range advantages necessary for high chemical selectivity. The microscale CIT has a reduced ion mean free path, allowing operation at higher pressures with less expensive and less bulky vacuum pumping system, and with lower battery power than conventional- and miniature-sized ion traps. The reduced electrode voltage enables integration of the microscale cylindrical ion trap with on-chip integrated circuit-based rf operation and detection electronics (i.e., cell phone electronics). Therefore, the full performance advantages of microscale cylindrical ion traps can be realized in truly field portable, handheld microanalysis systems.

  10. A Systematical Analysis of Tryptic Peptide Identification with Reverse Phase Liquid Chromatography and Electrospray Ion Trap Mass Spectrometry

    Institute of Scientific and Technical Information of China (English)

    Wei Sun; Shuzhen Wu; Xiaorong Wang; Dexian Zheng; Youhe Gao

    2004-01-01

    In this study we systematically analyzed the elution condition of tryptic peptides and the characteristics of identified peptides in reverse phase liquid chromatography and electrospray tandem mass spectrometry (RPLC-MS/MS) analysis. Following protein digestion with trypsin, the peptide mixture was analyzed by on-line RPLC-MS/MS. Bovine serum albumin (BSA) was used to optimize acetonitrile (ACN) elution gradient for tryptic peptides, and Cytochrome C was used to retest the gradient and the sensitivity of LC-MS/MS. The characteristics of identified peptides were also analyzed. In our experiments, the suitable ACN gradient is 5%to 30% for tryptic peptide elution and the sensitivity of LC-MS/MS is 50 fmol.Analysis of the tryptic peptides demonstrated that longer (more than 10 amino acids) and multi-charge state (+2,+3) peptides are likely to be identified, and the hydropathicity of the peptides might not be related to whether it is more likely to be identified or not. The number of identified peptides for a protein might be used to estimate its loading amount under the same sample background. Moreover, in this study the identified peptides present three types of redundancy, namely identification, charge, and sequence redundancy, which may repress low abundance protein identification.

  11. Wide-scope screening and quantification of 50 pesticides in wine by liquid chromatography/quadrupole time-of-flight mass spectrometry combined with liquid chromatography/quadrupole linear ion trap mass spectrometry.

    Science.gov (United States)

    He, Zeying; Xu, Yaping; Wang, Lu; Peng, Yi; Luo, Ming; Cheng, Haiyan; Liu, Xiaowei

    2016-04-01

    In this paper, a wide scope screening method of pesticides in wine was established using liquid chromatography/quadrupole time-of-flight mass spectrometry (LC-QTOF MS) and liquid chromatography/quadrupole linear ion trap mass spectrometry (LC-QqLIT MS). Information dependent acquisition (IDA) experiments are used to obtain both MS and MS/MS information for LC-QTOF MS analysis. For LC-QqLIT MS analysis, MS/MS spectra of target pesticides were simultaneously acquired using Enhanced Product Ion (EPI) mode at very low concentrations to increase the confidence in analytical results of multiple reaction monitoring (MRM) by library searching. Method validation was carried out using 50 pesticides commonly used in vineyards. The LOQs, linearity, repeatability were determined and good enough for quantification. The screening and quantification results obtained using LC-QTOF MS and LC-QqLIT MS were compared. Contaminants were screened against libraries containing over 2800 compounds based on accurate mass, isotopic patterns, and MS/MS spectra searching to extend the scope of this methodology to non-target screening.

  12. Hydrolysis of VX on Concrete: Rate of Degradation by Direct Surface Interrogation using an Ion Trap Secondary Ion Mass Spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Groenewold, Gary Steven; Appelhans, Anthony David; Gresham, Garold Linn; Olson, John Eric; Rowland, B.; Williams, j.; Jeffery, M. T.

    2002-09-01

    The nerve agent VX (O-ethyl S-2-diisopropylaminoethyl methylphosphonothiolate) is lethal at very low levels of exposure, which can occur by dermal contact with contaminated surfaces. Hence, behavior of VX in contact with common urban or industrial surfaces is a subject of acute interest. In the present study, VX was found to undergo complete degradation when in contact with concrete surfaces. The degradation was directly interrogated at submonolayer concentrations by periodically performing secondary ion mass spectrometry (SIMS) analyses after exposure of the concrete to VX. The abundance of the [VX + H]+ ion in the SIMS spectra was observed to decrease in an exponential fashion, consistent with first-order or pseudo-first-order behavior. This phenomenon enabled the rate constant to be determined at 0.005 min-1 at 25 C, which corresponds to a half-life of about 3 h on the concrete surface. The decrease in [VX + H]+ was accompanied by an increase in the abundance of the principal degradation product diisopropylaminoethanethiol (DESH), which arises by cleavage of the P-S bond. Degradation to form DESH is accompanied by the formation of ethyl methylphosphonic acid, which is observable only in the negative ion spectrum. A second degradation product was also implicated, which corresponded to a diisopropylvinylamine isomer (perhaps N,N-diisopropyl aziridinium) that arose via cleavage of the S-C bond. No evidence was observed for the formation of the toxic S-2-diisopropylaminoethyl methylphosphonothioic acid. The degradation rate constants were measured at four different temperatures (24-50 C), which resulted in a linear Arrhenius relationship and an activation energy of 52 kJ mol-1. This value agrees with previous values observed for VX hydrolysis in alkaline solutions, which suggests that the degradation of submonolayer VX is dominated by alkaline hydrolysis within the adventitious water film on the concrete surface.

  13. Characterization of metabolism of (+)-praeruptorin B and (+)-praeruptorin E in human and rat liver microsomes by liquid chromatography coupled with ion trap mass spectrometry and time-of-flight mass spectrometry.

    Science.gov (United States)

    Song, Yue-Lin; Yan, Ru; Jing, Wang-Hui; Zhao, Hai-Yu; Wang, Yi-Tao

    2011-03-30

    Peucedani Radix is a Chinese medicinal herb noted for its effects on treatments of respiratory and pulmonary disorders. As a part of a systematic pharmacokinetic evaluation of the herb in our laboratory, the present study investigated, for the first time, the metabolic profile of (+)-praeruptorin B (dPB) and (+)-praeruptorin E (dPE), two main bioactive constituents of Peucedani Radix in pooled liver microsomes of rats (RLMs) and humans (HLMs). dPE was eliminated faster than dPB in both species. The incubation of dPB with RLMs and HLMs resulted in eight (B1-B8) and nine (B1-B9) metabolites, respectively, while both RLMs and HLMs converted dPE into 13 metabolites (E1-13). Structures of all the metabolites were proposed through comparing their mass data obtained via tandem mass spectrometry on an MSD ion trap system (IT-MS/MS) coupled with high-resolution mass measurement by time-of-flight mass spectrometry (TOF-MS) with those of the respective parent compound. B1 and E1 were unambiguously identified as (-)-cis-khellactone. The formations of all the metabolites were NADPH-dependent. Oxidation and hydrolysis were demonstrated to be two predominant metabolic pathways of dPB and dPE. Oxidation initiated at either the C-3' or C-4' substituent, while hydrolysis only started from the C-3' substituent. Fragmentation of all metabolites followed similar pathways to those of the parent pyranocoumarins. The information on metabolic properties of dPB and dPE and the mass fragmentation profiles of their metabolites obtained in the present study will aid in characterization of metabolic profiles of other angular-type pyranocoumarins and further investigation of in vivo fates of these pyranocoumarins and the herb.

  14. Precision mass measurements for studies of nucleosynthesis via the rapid neutron-capture process Penning-trap mass measurements of neutron-rich cadmium and caesium isotopes

    CERN Document Server

    AUTHOR|(CDS)2085660; Litvinov, Yuri A.; Kreim, Susanne

    Although the theory for the rapid neutron-capture process (r-process) was developed more than 55 years ago, the astrophysical site is still under a debate. Theoretical studies predict that the r-process path proceeds through very neutron-rich nuclei with very asymmetric proton- to-neutron ratios. Knowledge about the properties of neutron-rich isotopes found in similar regions of the nuclear chart and furthermore suitable for r-process studies is still little or even not existing. The basic nuclear properties such as binding energies, half-lives, neutron-induced or neutron-capture reaction cross-sections, play an important role in theoretical simulations and can vary or even drastically alternate results of these studies. Therefore, a considerable effort was put forward to access neutron-rich isotopes at radioactive ion-beam facilities like ISOLDE at CERN. The goal of this PhD thesis is to describe the experimental work done for the precision mass measurements of neutron-rich cadmium (129−131 Cd) and caesium...

  15. Quantification of Lansoprazole in Oral Suspension by Ultra-High-Performance Liquid Chromatography Hybrid Ion-Trap Time-of-Flight Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Stacy D. Brown

    2011-01-01

    Full Text Available An LC-MS/MS method was developed and validated to be used as a stability indicating assay for the study of a 3 mg/mL lansoprazole oral suspension. The method utilizes a UPLC (ultra-performance liquid chromatography column and unique mass spectrometric detection (ion-trap time-of-flight (IT-TOF to achieve a sensitive (LOD 2 ng/mL, accurate, and reproducible quantification of lansoprazole. This method reports an intraday and interday coefficient of variation of 2.98 ± 2.17% (n=5 for each concentration for each day and 3.07 ± 0.89% (n=20 for each concentration, respectively. Calibration curves (5–25 μg/mL were found to be linear with an R2 value ranging from 0.9972 to 0.9991 on 4 different days. Accuracy of the assay, expressed as % error, ranged from 0.30 to 5.22%. This method is useful for monitoring the stability of lansoprazole in oral suspension.

  16. Polar organic chemical integrative sampling and liquid chromatography- electrospray/ion-trap mass spectrometry for assessing selected prescription and illicit drugs in treated sewage effluents

    Science.gov (United States)

    Jones-Lepp, T. L.; Alvarez, D.A.; Petty, J.D.; Huckins, J.N.

    2004-01-01

    The purpose of the research presented in this paper was twofold: (1) to demonstrate the coupling of two state-of-the-art techniques: a time-weighted polar organic chemical integrative sampler (POCIS) and microliquid chromatography-electrospray/ion-trap mass spectrometry and (2) to assess the ability of these methodologies to detect six drugs (azithromycin, fluoxetine, omeprazole, levothyroxine, methamphetamine, methylenedioxymethamphetamine [MDMA]) in a real-world environment, e.g., waste water effluent. In the effluent from three wastewater treatment plants (WWTPs), azithromycin was detected at concentrations ranging from 15 to 66 ng/L, which is equivalent to a total annual release of 1 to 4 kg into receiving waters. Detected and confirmed in the effluent from two WWTPs were two illicit drugs, methamphetamine and MDMA, at 2 and 0.5 ng/L, respectively. Although the ecotoxicologic significance of drugs in environmental matrices, particularly water, has not been closely examined, it can only be surmised that these substances have the potential to adversely affect biota that are continuously exposed to them even at very low levels. The potential for chronic effects on human health is also unknown but of increasing concern because of the multi-use character of water, particularly in densely populated, arid areas.

  17. Validation of a new liquid chromatography- tandem mass spectrometry ion-trap technique for the simultaneous determination of thirteen anticoagulant rodenticides, drugs, or natural products.

    Science.gov (United States)

    Fourel, Isabelle; Hugnet, Christophe; Goy-Thollot, Isabelle; Berny, Philippe

    2010-03-01

    The purpose of this study was to develop and validate a liquid chromatography-tandem mass spectrometry method for the identification and quantification of anticoagulant (anti-vitamin K or AVK) compounds, including rodenticides, drugs, and natural products because no published method could be found. The proposed method is based on ion-trap technology with electrospray ionization (ESI) and multiple reaction monitoring (MRM) technique. Each AVK is identified by means of its retention time, precursor ion, and two product ions. Plasma samples are extracted by liquid-liquid partition on Toxi-tube B((R)). The method was validated on dog plasma and gave good results in terms of specificity, linearity, and percent recovery for the 14 AVK tested (warfarin, acenocoumarol, bromadiolone, brodifacoum, chlorophacinone, coumatetralyl, dicoumarol, difenacoum, difethialone, flocoumafen, fluindione, phenindione, and tioclomarol). The limits of detection ranged from 5 to 25 ng/mL. Intraday repeatability was good, but interday repeatability was more variable though still sufficient for our diagnostic purposes. The technique was successfully applied in a series of clinical investigations to demonstrate its applicability in various animal species and gave very high sensitivity and specificity results.

  18. Trace analysis of pesticides in paddy field water by direct injection using liquid chromatography-quadrupole-linear ion trap-mass spectrometry.

    Science.gov (United States)

    Pareja, Lucía; Martínez-Bueno, M J; Cesio, Verónica; Heinzen, Horacio; Fernández-Alba, A R

    2011-07-29

    A multiresidue method was developed for the quantification and confirmation of 70 pesticides in paddy field water. After its filtration, water was injected directly in a liquid chromatograph coupled to a hybrid triple quadrupole-linear ion trap-mass spectrometer (QqLIT). The list of target analytes included organophosphates, phenylureas, sulfonylureas, carbamates, conazoles, imidazolinones and others compounds widely used in different countries where rice is cropped. Detection and quantification limits achieved were in the range from 0.4 to 80 ng L(-1) and from 2 to 150 ng L(-1), respectively. Correlation coefficients for the calibration curves in the range 0.1-50 μg L(-1) were higher than 0.99 except for diazinon (0.1-25 μg L(-1)). Only 9 pesticides presented more than 20% of signal suppression/enhancement, no matrix effect was observed in the studied conditions for the rest of the target pesticides. The method developed was used to investigate the occurrence of pesticides in 59 water samples collected in paddy fields located in Spain and Uruguay. The study shows the presence of bensulfuron methyl, tricyclazole, carbendazim, imidacloprid, tebuconazole and quinclorac in a concentration range from 0.08 to 7.20 μg L(-1).

  19. Identification of 3′,4′-Dimethoxy Flavonol-3-β-d-Glucopyranoside Metabolites in Rats by Liquid Chromatography-Electrospray Ionization Ion Trap Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Yuan Zhu

    2016-04-01

    Full Text Available A method using liquid chromatography-electrospray ionization ion trap mass spectrometry was established for the identification of metabolites in feces, urine and bile in rats after oral administration of 3′,4′-dimethoxy flavonol-3-β-d-glucopyranoside (abbreviated DF3G. Seven metabolites in rat feces, urine and bile were firstly identified on the basis of their MS fragmentation behaviors. Three metabolites were identified in the feces, 6 in the urine and 2 in the bile, which suggested that demethylation, deglycosylation and deglycosylation followed by glucuronide conjugation were the major metabolic pathways for DF3G in vivo. Hydrolyzation might be the first step in the absorption and metabolism of DF3G. The possible metabolic pathway was proposed for the first time. The established method was simple, reliable and sensitive, revealing that it could be used to rapidly screen and identify the structures of metabolites of DF3G to better understand its metabolism in vivo.

  20. Analysis of anthelmintics in surface water by ultra high performance liquid chromatography coupled to quadrupole linear ion trap tandem mass spectrometry.

    Science.gov (United States)

    Zrnčić, Mirta; Gros, Meritxell; Babić, Sandra; Kaštelan-Macan, Marija; Barcelo, Damia; Petrović, Mira

    2014-03-01

    A method based on ultra high performance liquid chromatography coupled to quadrupole linear ion trap mass spectrometry (UHPLC-QqLIT-MS) has been developed to investigate occurrence of 10 anthelmintic drugs from different structural groups (moxidectin, flubendazole, fenbendazole, levamisol, mebendazole, oxibendazole, albendazole, triclabendazole, febantel and praziquantel) in surface water. Analytes were pre-concentrated by solid phase extraction (SPE) using hydrophilic-lipophilic polymeric based sorbent. Quantification of investigated analytes was done using deuterated compounds as internal standards in order to minimize matrix effect. Analyte recoveries from spiked samples at two concentration levels were above 75% for most of the analytes. The main advantages of developed method are fast separation using UHPLC and therefore short analysis time, combined with good sensitivity which is demonstrated by low ngL(-1) detection limits. The developed method was applied for analysis of anthelmintics in the Llobregat River (NE Spain) and its main tributaries (rivers Anoia and Cardener). Eight out of ten anthelmintics were detected in all analyzed samples with the concentrations in low ngL(-1) level. The method fills the gap on analytical methodologies for determination of anthelmintic drugs in the environment.

  1. Characterization of cardamonin metabolism by P450 in different species via HPLC-ESI-ion trap and UPLC-ESI-quadrupole mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    Yuqi HE; Li YANG; Yong LIU; Jiang-wei ZHANG; Jun TANG; Juan SU; Yuan-yuan LI; Yan-liu LU; Chang-hong WANG; Ling YANG; Zheng-tao WANG

    2009-01-01

    Aim:To characterize the metabolism of cardamonin by the P450 enzymes in human and animal liver microsomes. Methods: Cardamonin was incubated with both human and animal liver microsomal incubation systems containing P450 reaction factors. High performance liquid chromatography coupled with ion trap mass spectrometry was used to identify the metabolites. Serial cardamonin dilutions were used to perform a kinetic study in human liver microsomes. Selective inhibitors of 7 of the major P450 isozymes were used to inhibit cardamonin hydroxylation to identify the isozymes involved in cardamonin metabolism. The cardamonin hydroxylation metabolic capacities of human and various other animals were investigated using the liver microsomal incubation system.Results: Two metabolites generated by the liver microsome system were detected and identified as hydroxylated cardamonin. The K_m and V_ (max) values for cardamonin hydroxylation were calculated as 32μmol/L and 35 pmotmol·~(-1)·mg~(-1), respectively.Fruafylline and clomethiazole significantly inhibited cardamonin hydroxylation. Guinea pigs showed the highest similarity to humans with respect to the metabolism of cardamonin.Conclusion: CYP 1A2 and 2E1 were identified as the P450 isozymes involved in the metabolism of cardamonin in human liver microsomes. Furthermore, our research suggests that guinea pigs could be used in the advanced pharmacokinetic studies of cardamonin in vivo.

  2. HPLC/ESI-quadrupole ion trap mass spectrometry for characterization and direct quantification of amphoteric and nonionic surfactants in aqueous samples

    Science.gov (United States)

    Levine, Lanfang H.; Garland, Jay L.; Johnson, Jodie V.

    2002-01-01

    An amphoteric (cocamidopropylbetaine, CAPB) and a nonionic (alcohol polyethoxylate, AE) surfactant were characterized by electrospray ionization quadrupole ion trap mass spectrometry (ESI-MS) as to their homologue distribution and ionization/fragmentation chemistry. Quantitative methods involving reversed-phase gradient HPLC and (+)ESI-MSn were developed to directly determine these surfactants in hydroponic plant growth medium that received simulated graywater. The predominant homologues, 12 C alkyl CAPB and 9 EO AE, were monitored to represent the total amount of the respective surfactants. The methods demonstrated dynamic linear ranges of 0.5-250 ng (r2 > 0.996) for CAPB and 8-560 ng (r2 > 0.998) for AE homologue mixture, corresponding to minimum quantification limits of 25 ppb CAPB and 0.4 ppm AE with 20-microL injections. This translated into an even lower limit for individual components due to the polydispersive nature of the surfactants. The procedure was successfully employed for the assessment of CAPB and AE biodegradation in a hydroponic plant growth system used as a graywater bioreactor.

  3. Identification of in vivo nitrosylated phytochelatins in Arabidopsis thaliana cells by liquid chromatography-direct electrospray-linear ion trap-mass spectrometry.

    Science.gov (United States)

    Elviri, L; Speroni, F; Careri, M; Mangia, A; di Toppi, L Sanità; Zottini, M

    2010-06-18

    Reversed-phase liquid chromatography (RPLC) and electrospray (ESI)-linear ion trap (LIT) mass spectrometry was applied to the direct characterization of in vivo S-nitrosylated (SNO) phytochelatins (PCs) expressed in cadmium-stressed Arabidopsis thaliana cells. Cys-nitrosylation is under discussion as in vivo redox-based post-translational modification of proteins and peptides in plants in which the -NO group is involved as signal molecule in different biological functions. The gas-phase ion chemistry of in vivo and in vitro generated SNO-PC(s) was compared with the aim of evaluating NO binding stability and improving MS knowledge about peptide nitrosation. Using RPLC separation and ESI-LIT-MS, mono-nitrosylated PCs were identified in in vivo cadmium treated A. thaliana cells without derivatization. The in vivo binding of the NO group to PC(2), PC(3) and PC(4) resulted to occur selectively on only one cystein residue. The fragmentation pathway energies of the in vitro GSNO-generated NO-PCs with respect to the in vivo NO-PCs were investigated, suggesting the presence of a different internal stability for these molecules. By carrying out MS(2) experiments on these quasi-symmetric peptides, the different stability degree of the NO group was demonstrated to be correlated with the PC chain length. In addition, the data obtained highlight a putative role of the adjacent Glu/Cys motif in the gas-phase stability of the NO-containing molecule.

  4. Linear ion-trap MSn with high resolution mass spectrometry reveals structural diversity of epidermal 1-O-acyl ceramide family in mouse epidermis.

    Science.gov (United States)

    Lin, Meei-Hua; Miner, Jeffery; Turk, John; Hsu, Fong-Fu

    2017-02-02

    1-O-acylceramide is a new class of epidermal ceramide found in humans and mice. Here, we report ESI linear ion-trap (LIT) multiple stage mass spectrometric (MSn) approach with high resolution towards structural characterization of this lipid family isolated from mice. Molecular species desorbed as the [M + H]+ ions was subjected to LIT MS2 to yield predominately the [M + H - H2O]+ ions, followed by MS3 to cleave the 1-O-acyl residue to yield the [M + H - H2O - (1-O-fatty acid)]+ ions. The structures of the N-acyl chain and long-chain base (LCB) of the molecule were determined by MS4 on ([M + H - H2O - (1-O-fatty acid)]+) ions that yielded multiple sets of specific ions. Using this approach, isomers varied in the 1-O-acyl (from 14:0- to 26:0-O-acyl) and N-acyl chains (from 20:0- to 26:0-N-acyl) with 18:1-sphingosine as the major LCB were found for the entire family. Minor isomers consisting of 16:1- 17:1-, 18:2-, and 19:1-sphingosine LCB, with odd fatty acyl chain, or with monounsaturated N- or O- fatty acyl substituents were also identified. An estimation of more than 700 1-O-acylceramide species, largely isobaric isomers are present, underscoring the complexity of this ceramide family.

  5. Studies on the metabolism of mitragynine, the main alkaloid of the herbal drug Kratom, in rat and human urine using liquid chromatography-linear ion trap mass spectrometry.

    Science.gov (United States)

    Philipp, Anika A; Wissenbach, Dirk K; Zoerntlein, Siegfried W; Klein, Oliver N; Kanogsunthornrat, Jidapha; Maurer, Hans H

    2009-08-01

    Mitragynine (MG) is an indole alkaloid of the Thai medicinal plant Mitragyna speciosa (Kratom in Thai) and reported to have opioid agonistic properties. Because of its stimulant and euphoric effects, Kratom is used as a herbal drug of abuse. The aim of the presented study is to identify the phase I and II metabolites of MG in rat and human urine after solid-phase extraction (SPE) using liquid chromatography-linear ion trap mass spectrometry providing detailed structure information in the MSn mode particularly with high resolution. The seven identified phase I metabolites indicated that MG was metabolized by hydrolysis of the methylester in position 16, O-demethylation of the 9-methoxy group and of the 17-methoxy group, followed, via the intermediate aldehydes, by oxidation to carboxylic acids or reduction to alcohols and combinations of some steps. In rats, four metabolites were additionally conjugated to glucuronides and one to sulfate, but in humans, three metabolites to glucuronides and three to sulfates.

  6. Determination of 23 β2-agonists and 5 β-blockers in animal muscle by high performance liquid chromatography-linear ion trap mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A high performance liquid chromatography-linear ion trap mass spectrometry method using isotope dilution technique has been developed for the simultaneous determination of 23 β2-agonists and 5 β-blockers in animal muscle tissues. Pork and chicken muscle samples were acid hydrolyzed and extracted with 5% trichloracetic acid in water, and then cleaned up using MCX solid phase extraction (SPE) cartridge. Methanol and 0.1% formic acid were used as mobile phases for gradient elution. A Waters AtlantisT3 column was used for separation. ESI positive ion scan mode was used with selective reaction monitoring. 9 β2-Agonists labeled by the deuterium isotope were used as internal standards for quantification. The linear ranges of 23 β2-agonists and 5 β-blockers were 5-200 μg/L, the coefficient of correlation was not less than 0.995, and the limit of detection for each compound in the muscle tissue was below 0.2 μg/kg. The recoveries of each compound in the spiked samples at three levels 5, 10, 20 μg/kg were in the range of 47.3%-123.7%, and the relative standard deviations were in the range of 3.2%-25.7%. The developed method is sensitive and specific for the determination of β2-agonists and β-blockers in pork and chicken muscle samples.

  7. Liquid chromatography-electrospray linear ion trap mass spectrometry analysis of targeted neuropeptides in Tac1(-/-) mouse spinal cords reveals significant lower concentration of opioid peptides.

    Science.gov (United States)

    Saidi, Mouna; Beaudry, Francis

    2015-08-01

    Tachykinin and opioid peptides play a central role in pain transmission, modulation and inhibition. The treatment of pain is very important in medicine and many studies using NK1 receptor antagonists failed to show significant analgesic effects in humans. Recent investigations suggest that both pronociceptive tachykinins and the analgesic opioid systems are important for normal pain sensation. The analysis of opioid peptides in Tac1(-/-) spinal cord tissues offers a great opportunity to verify the influence of the tachykinin system on specific opioid peptides. The objectives of this study were to develop an HPLC-MS/MRM assay to quantify targeted peptides in spinal cord tissues. Secondly, we wanted to verify if the Tac1(-/-) mouse endogenous opioid system is hampered and therefore affects significantly the pain modulatory pathways. Targeted neuropeptides were analyzed by high performance liquid chromatography linear ion trap mass spectrometry. Our results reveal that EM-2, Leu-Enk and Dyn A were down-regulated in Tac1(-/-) spinal cord tissues. Interestingly, Dyn A was almost 3 fold down-regulated (p<0.0001). No significant concentration differences were observed in mouse Tac1(-/-) spinal cords for Met-Enk and CGRP. The analysis of Tac1(-/-) mouse spinal cords revealed noteworthy decreases of EM-2, Leu-Enk and Dyn A concentrations which strongly suggest a significant impact on the endogenous pain-relieving mechanisms. These observations may have insightful impact on future analgesic drug developments and therapeutic strategies.

  8. Simultaneous identification and quantification of tetrodotoxin in fresh pufferfish and pufferfish-based products using immunoaffinity columns and liquid chromatography/quadrupole-linear ion trap mass spectrometry

    Science.gov (United States)

    Guo, Mengmeng; Wu, Haiyan; Jiang, Tao; Tan, Zhijun; Zhao, Chunxia; Zheng, Guanchao; Li, Zhaoxin; Zhai, Yuxiu

    2016-08-01

    In this study, we established a comprehensive method for simultaneous identification and quantification of tetrodotoxin (TTX) in fresh pufferfish tissues and pufferfish-based products using liquid chromatography/quadrupole-linear ion trap mass spectrometry (LC-QqLIT-MS). TTX was extracted by 1% acetic acid-methanol, and most of the lipids were then removed by freezing lipid precipitation, followed by purification and concentration using immunoaffinity columns (IACs). Matrix effects were substantially reduced due to the high specificity of the IACs, and thus, background interference was avoided. Quantitation analysis was therefore performed using an external calibration curve with standards prepared in mobile phase. The method was evaluated by fortifying samples at 1, 10, and 100 ng/g, respectively, and the recoveries ranged from 75.8%-107%, with a relative standard deviation of less than 15%. The TTX calibration curves were linear over the range of 1-1 000 μg/L, with a detection limit of 0.3 ng/g and a quantification limit of 1 ng/g. Using this method, samples can be further analyzed using an information-dependent acquisition (IDA) experiment, in the positive mode, from a single liquid chromatography-tandem mass spectrometry injection, which can provide an extra level of confirmation by matching the full product ion spectra acquired for a standard sample with those from an enhanced product ion (EPI) library. The scheduled multiple reaction monitoring method enabled TTX to be screened for, and TTX was positively identified using the IDA and EPI spectra. This method was successfully applied to analyze a total of 206 samples of fresh pufferfish tissues and pufferfish-based products. The results from this study show that the proposed method can be used to quantify and identify TTX in a single run with excellent sensitivity and reproducibility, and is suitable for the analysis of complex matrix pufferfish samples.

  9. Simultaneous determination of triazine herbicides in rice by high-performance liquid chromatography coupled with high resolution and high mass accuracy hybrid linear ion trap-orbitrap mass spectrometry.

    Science.gov (United States)

    Mou, Ren-Xiang; Chen, Ming-Xue; Cao, Zhao-Yun; Zhu, Zhi-Wei

    2011-11-07

    A method was developed for the simultaneous determination of 10 triazine herbicides (cyanazine, simazine, simetryn, metribuzin, atrazine, ametryn, terbuthylazine, prometryn, terbutryn, and dimethametryn) in rice samples by high resolution and high mass accuracy hybrid linear ion trap-Orbitrap mass spectrometer. After extraction with acetonitrile and evaporation, the herbicides were redissolved in n-hexane and purified on a Florisil solid-phase extraction column. All compounds were separated within 12 min, producing more than 11 data points for each herbicide and high mass accuracy quantified ions which the mass errors of absolute value were less than 1.9 ppm in pure solution and 2.1 ppm in the matrix-matched standards solution. The method was validated in terms of the limits of detection and the limits of quantification. The linearity was satisfactory, with a correlation coefficient of >0.9975. Precision and recovery studies were evaluated at three concentration levels for Japonica, Indica, and Glutinous rice matrix. The mean recoveries obtained for all analytes in spiked Xiushui 03, Liangyoupeijiu, and Taihunuo rice samples were 83.3-99.0%, 82.0-99.7%, and 84.2-99.4%, respectively, with relative standard deviation in range 1.7-10.6%, 1.2-10.7%, and 1.9-11.6% for spiked rice samples, respectively. The intra-day precision (n=5) for the 10 herbicides in rice samples spiked at an intermediate level was between 2.8% and 7.9%, and the inter-day precision over 10 days (n=10) was between 5.5% and 15.9%.

  10. Collision-induced dissociation pathways of yeast sphingolipids and their molecular profiling in total lipid extracts: a study by quadrupole TOF and linear ion trap-orbitrap mass spectrometry

    DEFF Research Database (Denmark)

    Ejsing, Christer S.; Moehring, Thomas; Bahr, Ute

    2006-01-01

    The yeast Saccharomyces cerevisiae synthesizes three classes of sphingolipids: inositolphosphoceramides (IPCs), mannosyl-inositolphosphoceramides (MIPCs), and mannosyl-diinositolphosphoceramides (M(IP)2C). Tandem mass spectrometry of their molecular anions on a hybrid quadrupole time-of-flight (Qq......TOF) instrument produced fragments of inositol-containing head groups, which were specific for each lipid class. MS(n) analysis performed on a hybrid linear ion trap-orbitrap (LTQ Orbitrap) mass spectrometer with better than 3 ppm mass accuracy identified fragment ions specific for the amide-linked fatty acid...

  11. Penning trap at IGISOL

    Energy Technology Data Exchange (ETDEWEB)

    Szerypo, J. E-mail: jerzy.szerypo@phys.jyu.fi; Jokinen, A.; Kolhinen, V.S.; Nieminen, A.; Rinta-Antila, S.; Aeystoe, J

    2002-04-22

    The IGISOL facility at the Department of Physics of the University of Jyvaeskylae (JYFL) is delivering radioactive beams of short-lived exotic nuclei, in particular the neutron-rich isotopes from the fission reaction. These nuclei are studied with the nuclear spectroscopy methods. In order to substantially increase the quality and sensitivity of such studies, the beam should undergo beam handling: cooling, bunching and isobaric purification. The first two processes are performed with the use of an RFQ cooler/buncher. The isobaric purification will be made by a Penning trap placed after the RF-cooler element. This contribution describes the current status of the Penning trap project and its future prospects. The latter comprise the precise nuclear mass measurements, nuclear spectroscopy in the Penning trap interior as well as the laser spectroscopy on the extracted beams.

  12. Microfabricated linear Paul-Straubel ion trap

    Science.gov (United States)

    Mangan, Michael A.; Blain, Matthew G.; Tigges, Chris P.; Linker, Kevin L.

    2011-04-19

    An array of microfabricated linear Paul-Straubel ion traps can be used for mass spectrometric applications. Each ion trap comprises two parallel inner RF electrodes and two parallel outer DC control electrodes symmetric about a central trap axis and suspended over an opening in a substrate. Neighboring ion traps in the array can share a common outer DC control electrode. The ions confined transversely by an RF quadrupole electric field potential well on the ion trap axis. The array can trap a wide array of ions.

  13. A hybrid liquid chromatography-mass spectrometry strategy in a forensic laboratory for opioid, cocaine and amphetamine classes in human urine using a hybrid linear ion trap-triple quadrupole mass spectrometer.

    Science.gov (United States)

    Dowling, Geraldine; Regan, Liam; Tierney, Julie; Nangle, Michael

    2010-10-29

    A rapid method has been developed to analyse morphine, codeine, morphine-3-glucuronide, 6-monoacetylmorphine, cocaine, benzoylegonine, buprenorphine, dihydrocodeine, cocaethylene, 3,4-methylenedioxyamphetamine, ketamine, 3,4-methylenedioxymethamphetamine, pseudoephedrine, lignocaine, benzylpiperazine, methamphetamine, amphetamine, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine and methadone in human urine. Urine samples were diluted with methanol:water (1:1, v/v) and sample aliquots were analysed by hybrid linear ion trap-triple quadrupole mass spectrometry with a runtime of 12.5 min. Multiple reaction monitoring (MRM) as survey scan and an enhanced product ion (EPI) scan as dependent scan were performed in an information-dependent acquisition (IDA) experiment. Finally, drug identification and confirmation was carried out by library search with a developed in-house MS/MS library based on EPI spectra at a collision energy spread of 35±15 in positive mode and MRM ratios. The method was validated in urine, according to the criteria defined in Commission Decision 2002/657/EC. At least two MRM transitions for each substance were monitored in addition to EPI spectra and deuterated analytes were used as internal standards for quantitation. The reporting level was 0.05 μg mL(-1) for the range of analytes tested. The regression coefficients (r(2)) for the calibration curves (0-4 μg mL(-1)) in the study were ≥0.98. The method proved to be simple and time efficient and was implemented as an analytical strategy for the illicit drug monitoring of opioids, cocaines and amphetamines in criminal samples from crime offenders, abusers or victims in the Republic of Ireland. To the best of our knowledge there are no hybrid LC-MS applications using MRM mode and product ion spectra in the linear ion trap mode for opioids, cocaines or amphetamines with validation data in urine.

  14. Mass spectrometry-based chemotaxonomic classification of Penicillium species (P. echinulatum, P. expansum, P. solitum, and P. oxalicum) and its correlation with antioxidant activity.

    Science.gov (United States)

    Kim, Hyang Yeon; Park, Hye Min; Lee, Choong Hwan

    2012-09-01

    In this study, 4 Penicillium species (17 strains) were classified on the basis of metabolite profile (chemotaxonomy) by using liquid chromatography-electrospray ionization ion trap-mass spectrometry (LC-ESI-MS), gas chromatography-ion trap-mass spectrometry (GC-IT-MS) and multivariate statistical analysis. The LC-ESI-MS-based dendrogram was similar to the internal transcribed spacer (ITS)-based dendrogram, in that Penicillium oxalicum was separated from the other 3 species. Moreover, vermiculidiol, meleagrin, oxaline, glandicolin A and B, and secalonic acid D were identified as metabolites that enable discrimination of Penicillium species by partial least squares discriminant analysis (PLS-DA). Evaluation of the species-specific metabolites produced by P. expansum, P. echinulatum, and P. solitum revealed that the 3 species differed from each other. On the other hand, GC-IT-MS-based dendrogram revealed that P. expansum was clearly classified separately from the other 3 species, and this result correlated with the antioxidant activity of the 4 species: P. expansum had a higher radical scavenging activity than the other 3 species. The metabolites produced in higher amounts in P. expansum were gluconic acid (12, 29, 33); andrastin A (16), B (15), and C (17); chaetoglobosin C (14), a class of sugar (31, 32); and salicylic acid (28). The results of this study demonstrated that metabolite-based chemotaxonomy could be used not only as a classification method but also as a tool for evaluation of species-specific activities.

  15. Status and Outlook of CHIP-TRAP: the Central Michigan University High Precision Penning Trap

    CERN Document Server

    Redshaw, Matthew; Hawks, Paul; Gamage, Nadeesha D; Hunt, Curtis; Kandegedara, Rathnayake M E B; Ratnayake, Ishara S; Sharp, Lance

    2015-01-01

    At Central Michigan University we are developing a high-precision Penning trap mass spectrometer (CHIP-TRAP)that will focus on measurements with long-lived radioactive isotopes. CHIP-TRAP will consist of a pair of hyperbolic precision-measurement Penning traps, and a cylindrical capture/?filter trap in a 12 T magnetic field. Ions will be produced by external ion sources, including a laser ablation source, and transported to the capture trap at low energies enabling ions of a given m=q ratio to be selected via their time-of-flight. In the capture trap, contaminant ions will be removed with a mass-selective rf dipole excitation and the ion of interest will be transported to the measurement traps. A phase-sensitive image charge detection technique will be used for simultaneous cyclotron frequency measurements on single ions in the two precision traps, resulting in a reduction in statistical uncertainty due to magnetic field fluctuations.

  16. Development of a method for comprehensive and quantitative analysis of plant hormones by highly sensitive nanoflow liquid chromatography-electrospray ionization-ion trap mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Izumi, Yoshihiro; Okazawa, Atsushi; Bamba, Takeshi; Kobayashi, Akio [Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Fukusaki, Eiichiro, E-mail: fukusaki@bio.eng.osaka-u.ac.jp [Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2009-08-26

    In recent plant hormone research, there is an increased demand for a highly sensitive and comprehensive analytical approach to elucidate the hormonal signaling networks, functions, and dynamics. We have demonstrated the high sensitivity of a comprehensive and quantitative analytical method developed with nanoflow liquid chromatography-electrospray ionization-ion trap mass spectrometry (LC-ESI-IT-MS/MS) under multiple-reaction monitoring (MRM) in plant hormone profiling. Unlabeled and deuterium-labeled isotopomers of four classes of plant hormones and their derivatives, auxins, cytokinins (CK), abscisic acid (ABA), and gibberellins (GA), were analyzed by this method. The optimized nanoflow-LC-ESI-IT-MS/MS method showed ca. 5-10-fold greater sensitivity than capillary-LC-ESI-IT-MS/MS, and the detection limits (S/N = 3) of several plant hormones were in the sub-fmol range. The results showed excellent linearity (R{sup 2} values of 0.9937-1.0000) and reproducibility of elution times (relative standard deviations, RSDs, <1.1%) and peak areas (RSDs, <10.7%) for all target compounds. Further, sample purification using Oasis HLB and Oasis MCX cartridges significantly decreased the ion-suppressing effects of biological matrix as compared to the purification using only Oasis HLB cartridge. The optimized nanoflow-LC-ESI-IT-MS/MS method was successfully used to analyze endogenous plant hormones in Arabidopsis and tobacco samples. The samples used in this analysis were extracted from only 17 tobacco dry seeds (1 mg DW), indicating that the efficiency of analysis of endogenous plant hormones strongly depends on the detection sensitivity of the method. Our analytical approach will be useful for in-depth studies on complex plant hormonal metabolism.

  17. Control of the environmental inluences on THe-Trap on the example of the determination of the mass ratio of carbon-12 to oxygen-16; Kontrolle der Umwelteinfluesse auf THe-Trap am Beispiel der Bestimmung des Massenverhaeltnisses von Kohlenstoff-12 zu Sauerstoff-16

    Energy Technology Data Exchange (ETDEWEB)

    Streubel, Sebastian Dennis

    2014-04-16

    Tritium-Helium-3-Trap (THe-Trap) is a Penning-trap setup dedicated to measure the {sup 3}H to {sup 3}He mass ratio with a relative uncertainty of better than 10{sup -11}. This is 40 times more precise than the currently adopted value and, thus, will help to investigate possible systematic uncertainties of the Karlsruhe Tritium Neutrino experiment (KATRIN). To achieve the desired level of uncertainty, several environmental influences such as atmospheric pressure shifts and magnetic field fluctuations have to be suppressed. With the implemented stabilization system, the relative magnetic field drift could be reduced to a few 10{sup -12}/h for a time span of several weeks. Within the context of this thesis a mass ratio measurement of {sup 12}C{sup 4+} to {sup 16}O{sup 5+} was performed to characterize systematic effects. This measurement yielded a statistical uncertainty of 6.3 x 10{sup -11}, which can easily be improved with more statistics, i.e. a longer measurement time. While the systematic uncertainty for {sup 12}C{sup 4+}-ions were under control at the 10{sup -11} level, the systematic shifts could not be quantified for {sup 16}O{sup 5+} due to poor vacuum conditions. Without these corrections, a systematic uncertainty of 1.2.10{sup -10} could be achieved for the {sup 12}C/{sup 16}O mass ratio measurement.

  18. Classification of Jet Fuels by Fuzzy Rule-Building Expert Systems Applied to Three-Way Data by Fast Gas Chromatography-Fast Scanning Quadrupole Ion Trap Mass Spectrometry

    Science.gov (United States)

    2011-01-01

    car - rier gas speed, and a higher head pressure, etc., fast GC separation can be realized. Compared with conventional GC, fast GC offers the...themost common, sensitive, and informativedetectors for GC, MS has promise for the composition-property correlation studyof jet fuels. Time-of-flight ( ToF ... ToF -MS [42]. However, they have the disadvantage of relatively higher costs to purchase and maintain compared to ion trap mass spectrometers. Most

  19. Quantification of intermediate-abundance proteins in serum by multiple reaction monitoring mass spectrometry in a single-quadrupole ion trap.

    Science.gov (United States)

    Lin, Shanhua; Shaler, Thomas A; Becker, Christopher H

    2006-08-15

    A method is presented to quantify intermediate-abundance proteins in human serum using a single-quadrupole linear ion trap mass spectrometer-in contrast, for example, to a triple-quadrupole mass spectrometer. Stable-isotope-labeled (tryptic) peptides are spiked into digested protein samples as internal standards, aligned with the traditional isotope dilution approach. As a proof-of-concept experiment, four proteins of intermediate abundance were selected, coagulation factor V, adiponectin, C-reactive protein (CRP), and thyroxine binding globulin. Stable-isotope-labeled peptides were synthesized with one tryptic sequence from each of these proteins. The normal human serum concentration ranges of these proteins are from 1 to 30 microg/mL (or 20 to 650 pmol/mL). These labeled peptides and their endogenous counterparts were analyzed by LC-MS/MS using multiple reaction monitoring, a multiplexed form of the selected reaction monitoring technique. For these experiments, only one chromatographic dimension (on-line reversed-phase capillary column) was used. Improved limits of detection will result with multidimensional chromatographic methods utilizing more material per sample. Standard curves of the spiked calibrants were generated with concentrations ranging from 3 to 700 pmol/mL using both neat solutions and peptides spiked into the complex matrix of digested serum protein solution where ion suppression effects and interferences are common. Endogenous protein concentrations were determined by comparing MS/MS peak areas of the endogenous peptides to the isotopically labeled internal calibrants. The derived concentrations from a normal human serum pool (neglecting loss of material during sample processing) were 9.2, 110, 120, and 246 pmol/mL for coagulation factor V, adiponectin, CRP, and thyroxine binding globulin, respectively. These concentrations generally agree with the reported normal ranges for these proteins. As a measure of analytical reproducibility of this

  20. Trapped antihydrogen

    CERN Document Server

    Butler, E; Ashkezari, M D; Baquero-Ruiz, M; Bertsche, W; Bowe, P D; Cesar, C L; Chapman, S; Charlton, M; Deller, A; Eriksson, S; Fajans, J; Friesen, T; Fujiwara, M C; Gill, D R; Gutierrez, A; Hangst, J S; Hardy, W N; Hayden, M E; Humphries, A J; Hydomako, R; Jenkins, M J; Jonsell, S; Jørgensen, L V; Kemp, S L; Kurchaninov, L; Madsen, N; Menary, S; Nolan, P; Olchanski, K; Olin, A; Povilus, A; Pusa, P; Rasmussen, C Ø; Robicheaux, F; Sarid, E; Seif el Nasr, S; Silveira, D M; So, C; Storey, J W; Thompson, R I; van der Werf, D P; Wurtele, J S; Yamazaki,Y

    2012-01-01

    Precision spectroscopic comparison of hydrogen and antihydrogen holds the promise of a sensitive test of the Charge-Parity-Time theorem and matter-antimatter equivalence. The clearest path towards realising this goal is to hold a sample of antihydrogen in an atomic trap for interrogation by electromagnetic radiation. Achieving this poses a huge experimental challenge, as state-of-the-art magnetic-minimum atom traps have well depths of only ∼1 T (∼0.5 K for ground state antihydrogen atoms). The atoms annihilate on contact with matter and must be ‘born’ inside the magnetic trap with low kinetic energies. At the ALPHA experiment, antihydrogen atoms are produced from antiprotons and positrons stored in the form of non-neutral plasmas, where the typical electrostatic potential energy per particle is on the order of electronvolts, more than 104 times the maximum trappable kinetic energy. In November 2010, ALPHA published the observation of 38 antiproton annihilations due to antihydrogen atoms that had been ...

  1. Bulk derivatization and cation exchange restricted access media-based trap-and-elute liquid chromatography–mass spectrometry method for determination of trace estrogens in serum

    Energy Technology Data Exchange (ETDEWEB)

    Beinhauer, Jana [Department of Biochemistry, Faculty of Science, Palacký University, Šlechtitelů 11, CZ-783 71 Olomouc (Czech Republic); Centre of the Region Haná for Biotechnological and Agricultural Research - Department of Protein Biochemistry and Proteomics, Faculty of Science, Palacký University, Šlechtitelů 11, CZ-783 71 Olomouc (Czech Republic); Bian, Liangqiao [Shimadzu Center for Advanced Analytical Chemistry, The University of Texas at Arlington, Arlington, TX (United States); Shimadzu Institute for Research Technologies, The University of Texas at Arlington, Arlington, TX (United States); Fan, Hui [Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX (United States); Šebela, Marek [Department of Biochemistry, Faculty of Science, Palacký University, Šlechtitelů 11, CZ-783 71 Olomouc (Czech Republic); Centre of the Region Haná for Biotechnological and Agricultural Research - Department of Protein Biochemistry and Proteomics, Faculty of Science, Palacký University, Šlechtitelů 11, CZ-783 71 Olomouc (Czech Republic); Kukula, Maciej [Shimadzu Center for Advanced Analytical Chemistry, The University of Texas at Arlington, Arlington, TX (United States); Shimadzu Institute for Research Technologies, The University of Texas at Arlington, Arlington, TX (United States); Barrera, Jose A. [Shimadzu Institute for Research Technologies, The University of Texas at Arlington, Arlington, TX (United States); and others

    2015-02-09

    Highlights: • Analysis of estrogens in small volume samples at low parts-per-trillion concentration. • Charged bulk derivatization facilitates on-line ion exchange sample preparation. • On-line WCX restricted access media traps analytes, but not proteins and lipids. • Complete preparation and LC–MS/MS analysis completed in 30 min/sample. - Abstract: Estrone (E1), estradiols (α/β-E2), and estriol (E3) are four major metabolically active estrogens exerting strong biological activities at very low circulating concentrations. This paper reports a sensitive and efficient method with automated, on-line clean-up and detection to determine trace estrogens in a small volume of serum samples using liquid chromatography–electrospray ionization–tandem mass spectrometry directly, without off-line liquid–liquid or solid-phase extraction pretreatments. Serum aliquots (charcoal stripped fetal bovine serum, 100 μL) were spiked with four estrogen standards and their corresponding isotope-labeled internal standards, then bulk derivatized with 2-fluoro-1-methyl-pyridium p-toluenesulfonate (2-FMP) to establish the calibration curves and perform method validation. Calibration was established in the concentration ranges of 5–1000 pg mL{sup −1}, and demonstrated good linearity of R{sup 2} from 0.9944 to 0.9997 for the four derivatized estrogens. The lower detection limits obtained were 3–7 pg mL{sup −1}. Good accuracy and precision in the range of 86–112% and 2.3–11.9%, respectively, were observed for the quality control (QC) samples at low, medium, and high concentration levels. The stability tests showed that the derivatized serum samples were stable 8 h after derivatization at room temperature and at least to 48 h if stored at −20 °C. The method was applied to measure trace estrogens in real human and bovine serum samples, and three of four estrogen compounds studied were observed and quantified.

  2. An introduction to the trapping of clusters with ion traps and electrostatic storage devices

    Energy Technology Data Exchange (ETDEWEB)

    Bredy, R; Bernard, J; Chen, L; Montagne, G; Li, B; Martin, S [Universite de Lyon, F-69622, Lyon (France); Universite Lyon 1, Villeurbanne (France); CNRS, UMR 5579, LASIM (France)

    2009-08-14

    This paper presents an introduction to the application of ion traps and storage devices for cluster physics. Some experiments involving cluster ions in trapping devices such as Penning traps, Paul traps, quadrupole or multipole linear traps are briefly discussed. Electrostatic ion storage rings and traps which allow for the storage of fast ion beams without mass limitation are presented as well. We also report on the recently developed mini-ring, a compact electrostatic ion storage ring for cluster, molecular and biomolecular ion studies. (review)

  3. Comparison of triple quadrupole, hybrid linear ion trap triple quadrupole, time-of-flight and LTQ-Orbitrap mass spectrometers in drug discovery phase metabolite screening and identification in vitro--amitriptyline and verapamil as model compounds.

    Science.gov (United States)

    Rousu, Timo; Herttuainen, Jukka; Tolonen, Ari

    2010-04-15

    Liquid chromatography in combination with mass spectrometry (LC/MS) is a superior analytical technique for metabolite profiling and identification studies performed in drug discovery and development laboratories. In the early phase of drug discovery the analytical approach should be both time- and cost-effective, thus providing as much data as possible with only one visit to the laboratory, without the need for further experiments. Recent developments in mass spectrometers have created a situation where many different mass spectrometers are available for the task, each with their specific strengths and drawbacks. We compared the metabolite screening properties of four main types of mass spectrometers used in analytical laboratories, considering both the ability to detect the metabolites and provide structural information, as well as the issues related to time consumption in laboratory and thereafter in data processing. Human liver microsomal incubations with amitriptyline and verapamil were used as test samples, and early-phase 'one lab visit only' approaches were used with all instruments. In total, 28 amitriptyline and 69 verapamil metabolites were found and tentatively identified. Time-of-flight mass spectrometry (TOFMS) was the only approach detecting all of them, shown to be the most suitable instrument for elucidating as comprehensive metabolite profile as possible leading also to lowest overall time consumption together with the LTQ-Orbitrap approach. The latter however suffered from lower detection sensitivity and false negatives, and due to slow data acquisition rate required slower chromatography. Approaches with triple quadrupole mass spectrometry (QqQ) and hybrid linear ion trap triple quadrupole mass spectrometry (Q-Trap) provided the highest amount of fragment ion data for structural elucidation, but, in addition to being unable to produce very high-important accurate mass data, they suffered from many false negatives, and especially with the Qq

  4. Identification of alkyl dimethylbenzylammonium surfactants in water samples by solid-phase extraction followed by ion trap LC/MS and LC/MS/MS

    Science.gov (United States)

    Ferrer, I.; Furlong, E.T.

    2001-01-01

    A novel methodology was developed for the determination of alkyl (C12, C14, and C16) dimethylbenzylammonium chloride (benzalkonium chloride or BAC, Chemical Abstract Service number: 8001-54-5) in water samples. This method is based on solid-phase extraction (SPE) using polymeric cartridges, followed by high-performance liquid chromatography/ion trap mass spectrometry (LC/MS) and tandem mass spectrometry(MS/MS) detection, equipped with an electrospray interface in positive ion mode. Chromatographic separation was achieved for three BAC homologues by using a C18 column and a gradient of acetonitrile/10 millimolar aqueous ammonium formate. Total method recoveries were higher than 71% in different water matrices. The main ions observed by LC/MS were at mass-to-charge ratios (m/z) of 304, 332, and 360, which correspond to the molecular ions of the C12, C14, and C16 alkyl BAC, respectively. The unequivocal structural identification of these compounds in water samples was performed by LC/MS/MS after isolation and subsequent fragmentation of each molecular ion. The main fragmentation observed for the three different homologues corresponded to the loss of the toluyl group in the chemical structure, which leads to the fragment ions at m/z 212, 240, and 268 and a tropylium ion, characteristic of all homologues, at m/z 91. Detection limits for the methodology developed in this work were in the low nanogram-per-liter range. Concentration levels of BAC - ranging from 1.2 to 36.6 micrograms per liter - were found in surface-water samples collected downstream from different wastewater-treatment discharges, thus indicating its input and persistence through the wastewater-treatment process.

  5. Determination of hemoglobin adduct of a musk xylene metabolite in trout as biomarker of exposure by gas chromatography mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    MOTTALEB Mohammad Abdul; KARIM Mohammad Rezaul

    2005-01-01

    Musk xylene(MX) is frequently used as fragrances in formulation of personal care products. Quantification of a bound 4-aminoMX(4-AMX) as cysteine adducts in trout hemoglobin(Hb) was made by gas chromatography-ion trap-mass spectrometry(GC/MS). The Hb samples were collected from trout after 24 h exposure to MX at 10 μg/g, and or menhaden oil(control). The formation of cysteine-Hb adduct was observed from nitroso derivative of MX, released by alkaline hydrolysis. The released 4-AMX metabolite was extracted in nhexane. The extract was then reduced by evaporation, and analyzed by GC/MS. When similar agreement of mass spectral features and retention time of 4-AMX were obtained in both standard and sample solutions, the presence of 4-AMX metabolite in the Hb was confirmed.The concentration of 4-AMX was found to be 3.1 x 10-6- 6.9 x 10-6 mg/g in the Hb solution. Quantitation was made based on an internal standard, a calibration plot, and response factor. In the non-hydrolyzed and laboratory blank extracts, the 4-AMX metabolite was not detected. Additionally, coeluting and interfering ions were observed in the biological samples.

  6. Computer model for analyzing sodium cold traps

    Energy Technology Data Exchange (ETDEWEB)

    McPheeters, C C; Raue, D J

    1983-05-01

    A computer model was developed to simulate the processes that occur in sodium cold traps. The Model for Analyzing Sodium Cold Traps (MASCOT) simulates any desired configuration of mesh arrangements and dimensions and calculates pressure drops and flow distributions, temperature profiles, impurity concentration profiles, and impurity mass distributions. The calculated pressure drop as a function of impurity mass content determines the capacity of the cold trap. The accuracy of the model was checked by comparing calculated mass distributions with experimentally determined mass distributions from literature publications and with results from our own cold trap experiments. The comparisons were excellent in all cases. A parametric study was performed to determine which design variables are most important in maximizing cold trap capacity.

  7. Accretion discs trapped near corotation

    OpenAIRE

    D'Angelo, C.R.; Spruit, H.C.

    2012-01-01

    We show that discs accreting on to the magnetosphere of a rotating star can end up in a trapped state, in which the inner edge of the disc stays near the corotation radius, even at low and varying accretion rates. The accretion in these trapped states can be steady or cyclic; we explore these states over a wide range of parameter space. We find two distinct regions of instability: one related to the buildup and release of mass in the disc outside corotation, and the other to mass storage with...

  8. Multi-mycotoxin Analysis of Finished Grain and Nut Products Using Ultrahigh-Performance Liquid Chromatography and Positive Electrospray Ionization-Quadrupole Orbital Ion Trap High-Resolution Mass Spectrometry.

    Science.gov (United States)

    Liao, Chia-Ding; Wong, Jon W; Zhang, Kai; Yang, Paul; Wittenberg, James B; Trucksess, Mary W; Hayward, Douglas G; Lee, Nathaniel S; Chang, James S

    2015-09-23

    Ultrahigh-performance liquid chromatography using positive electrospray ionization and quadrupole orbital ion trap high-resolution mass spectrometry was evaluated for analyzing mycotoxins in finished cereal and nut products. Optimizing the orbital ion trap mass analyzer in full-scan mode using mycotoxin-fortified matrix extracts gave mass accuracies, δM, of mycotoxin-dependent, ranging from 0.02 to 11.6 μg/kg. Mean recoveries and standard deviations for mycotoxins from acetonitrile/water extraction at their relevant fortification levels were 91 ± 10, 94 ± 10, 98 ± 12, 91 ± 13, 99 ± 15, and 93 ± 17% for corn, rice, wheat, almond, peanut, and pistachio, respectively. Nineteen mycotoxins with concentrations ranging from 0.3 (aflatoxin B1 in peanut and almond) to 1175 μg/kg (fumonisin B1 in corn flour) were found in 35 of the 70 commercial grain and nut samples surveyed. Mycotoxins could be identified at δM mycotoxins in finished grain and nut products.

  9. Multipole Traps as Tools in Environmental Studies

    CERN Document Server

    Mihalcea, Bogdan M; Giurgiu, Liviu C; Groza, Andreea; Surmeian, Agavni; Ganciu, Mihai; Filinov, Vladimir; Lapitsky, Dmitry; Deputatova, Lidiya; Vasilyak, Leonid; Pecherkin, Vladimir; Vladimirov, Vladimir; Syrovatka, Roman

    2015-01-01

    Trapping of microparticles, nanoparticles and aerosols is an issue of major interest for physics and chemistry. We present a setup intended for microparticle trapping in multipole linear Paul trap geometries, operating under Standard Ambient Temperature and Pressure (SATP) conditions. A 16-electrode linear trap geometry has been designed and tested, with an aim to confine a larger number of particles with respect to quadrupole traps and thus enhance the signal to noise ratio, as well as to study microparticle dynamical stability in electrodynamic fields. Experimental tests and numerical simulations suggest that multipole traps are very suited for high precision mass spectrometry measurements in case of different microparticle species or to identify the presence of certain aerosols and polluting agents in the atmosphere. Particle traps represent versatile tools for environment monitoring or for the study of many-body Coulomb systems and dusty plasmas.

  10. Comprehensive two-dimensional liquid chromatography: Ion chromatography × reversed-phase liquid chromatography for separation of low-molar-mass organic acids

    NARCIS (Netherlands)

    S.S. Brudin; R.A. Shellie; P.R. Haddad; P.J. Schoenmakers

    2010-01-01

    In the work presented here a novel approach to comprehensive two-dimensional liquid chromatography is evaluated. Ion chromatography is chosen for the first-dimension separation and reversed-phase liquid chromatography is chosen for the second-dimension separation mode. The coupling of these modes is

  11. Annual Trapping Proposal 1985

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Annual Trapping Plan for the 1984-1985 trapping season at Clarence Cannon NWR outlines rules and regulations for the trapping of beaver and muskrat on the...

  12. An atmospheric pressure chemical ionization-ion-trap mass spectrometer for the on-line analysis of volatile compounds in foods: a tool for linking aroma release to aroma perception.

    Science.gov (United States)

    Le Quéré, Jean-Luc; Gierczynski, Isabelle; Sémon, Etienne

    2014-09-01

    An atmospheric pressure chemical ionization ion-trap mass spectrometer was set up for the on-line analysis of aroma compounds. This instrument, which has been successfully employed for some years in several in vitro and in vivo flavour release studies, is described for the first time in detail. The ion source was fashioned from polyether ether ketone and operated at ambient pressure and temperature making use of a discharge corona pin facing coaxially the capillary ion entrance of the ion-trap mass spectrometer. Linear dynamic ranges (LDR), limits of detection (LOD) and other analytical characteristics have been re-evaluated. LDRs and LODs have been found fully compatible with the concentrations of aroma compounds commonly found in foods. Thus, detection limits have been found in the low ppt range for common flavouring aroma compounds (for example 5.3 ppt (0.82 ppbV) for ethyl hexanoate and 4.8 ppt (1.0 ppbV) for 2,5-dimethylpyrazine). This makes the instrument applicable for in vitro and in vivo aroma release investigations. The use of dynamic sensory techniques such as the temporal dominance of sensations (TDS) method conducted simultaneously with in vivo aroma release measurements allowed to get some new insights in the link between flavour release and flavour perception.

  13. Simultaneous qualitative and quantitative analysis of 21 mycotoxins in Radix Paeoniae Alba by ultra-high performance liquid chromatography quadrupole linear ion trap mass spectrometry and QuEChERS for sample preparation.

    Science.gov (United States)

    Xing, Yanyan; Meng, Wenting; Sun, Wanyang; Li, Dongxiang; Yu, Zhiguo; Tong, Ling; Zhao, Yunli

    2016-09-15

    A high-throughput method for simultaneous qualitative and quantitative analysis of 21 mycotoxins in Radix Paeoniae Alba (RPA) was developed by coupling the modified QuEChERS method with ultra-high performance liquid chromatography quadrupole linear ion trap mass spectrometry (UHPLC-QqLIT-MS). The 21 mycotoxins were extracted and cleaned up using QuEChERS-based procedure, then further separated on a C18 column and detected by a hybrid triple quadrupole linear ion trap mass spectrometer equipped with electrospray ionization source in the multiple reaction monitoring-information dependent acquisition-enhanced product ion (MRM-IDA-EPI) mode. Under this technique, 13 mycotoxins were detected using acetonitrile and water containing 0.1% formic acid as the mobile phase in positive mode while the other 8 mycotoxins were detected using acetonitrile and water containing 0.1% ammonia as the mobile phase in negative mode. The calibration curves of all analytes showed good linearity (r(2)>0.995) within test ranges. The limits of detection and quantification ranged from 0.031 to 5.4μg/kg and 0.20 to 22μg/kg, respectively. Additionally, recoveries were all above 75.3% with relative standard deviations within 15%. The method proposed herein with significant advantages including simple pretreatment, rapid determination as well as high sensitivity, accuracy and throughput would be a preferred candidate for the determination and quantification of multi-class mycotoxin contaminants in real samples.

  14. In situ measurements of krypton in xenon gas with a quadrupole mass spectrometer following a cold-trap at a temporarily reduced pumping speed

    Science.gov (United States)

    Brown, E.; Rosendahl, S.; Huhmann, C.; Weinheimer, C.; Kettling, H.

    2013-02-01

    A new method for measuring trace amounts of krypton in xenon using a cold trap with a residual gas analyzer has been developed, which achieves an increased sensitivity by temporarily reducing the pumping speed while expending a minimal amount of xenon. By partially closing a custom built butterfly valve between the measurement chamber and the turbomolecular pump, a sensitivity of 40 ppt has been reached. This method has been tested on an ultra-pure gas sample from Air Liquide with an unknown intrinsic krypton concentration, yielding a krypton concentration of 330±200 ppt.

  15. In situ measurements of Krypton in Xenon gas with a quadrupole mass spectrometer following a cold-trap at a temporarily reduced pumping speed

    CERN Document Server

    Brown, Ethan; Huhmann, Christian; Weinheimer, Christian; Kettling, Hans

    2012-01-01

    A new method for measuring trace amounts of krypton in xenon using a cold trap with a residual gas analyzer has been developed, which achieves an increased sensitivity by temporarily reducing the pumping speed while expending a minimal amount of xenon. By partially closing a custom built butterfly valve between the measurement chamber and the turbomolecular pump, a sensitivity of 40 ppt has been reached. This method has been tested on an ultra-pure gas sample from Air Liquide with an unknown intrinsic krypton concentration, yielding a krypton concentration of $330 \\pm 200$ ppt.

  16. Active Stabilization of Ion Trap Radiofrequency Potentials

    CERN Document Server

    Johnson, K G; Neyenhuis, B; Mizrahi, J; Monroe, C

    2016-01-01

    We actively stabilize the harmonic oscillation frequency of a laser-cooled atomic ion confined in a rf Paul trap by sampling and rectifying the high voltage rf applied to the trap electrodes. We are able to stabilize the 1 MHz atomic oscillation frequency to better than 10 Hz, or 10 ppm. This represents a suppression of ambient noise on the rf circuit by 34 dB. This technique could impact the sensitivity of ion trap mass spectrometry and the fidelity of quantum operations in ion trap quantum information applications.

  17. In situ measurements of krypton in xenon gas with a quadrupole mass spectrometer following a cold-trap at a temporarily reduced pumping speed

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Ethan; Rosendahl, Stephan; Huhmann, Christian; Kettling, Hans; Schlak, Martin; Weinheimer, Christian [Muenster Univ. (Germany). Inst. fuer Kernphysik

    2013-07-01

    Liquid xenon detectors have risen to be extremely competitive for dark matter and neutrinoless double-beta decay searches. In order to achieve the required sensitivity, backgrounds must be reduced substantially. One important background is the beta-decay of {sup 85}Kr, which constitutes a uniform internal background in liquid xenon detectors. Cryogenic distillation can be used to reduce the krypton concentration to acceptable levels, but gas diagnostics become incredibly difficult at these ultra-pure levels. A new method for measuring the concentration of krypton in xenon has been developed, expanding on the existing technique of a cold trap and a Residual Gas Analyzer (RGA). By using a liquid nitrogen cold trap, one can take advantage of the difference in vapor pressures of krypton in xenon to freeze most of the xenon gas while allowing the krypton to pass to the measurement chamber. Here, only a few milliliters of xenon is expended in the measurement, while achieving a sensitivity of sub ppb (parts per billion). The key change is the use of a butterfly valve to partially close the opening in front of the turbomolecular pump, thereby reducing the effective pumping speed and enhancing the RGA signal.

  18. Characterization of oligosaccharides with capillary high performance anion exchange chromatography hyphenated to pulsed amperometric detection and ion trap mass spectrometry : application to the analysis of human lysosomal disorders

    NARCIS (Netherlands)

    Bruggink, Cornelis

    2013-01-01

    The development of a capillary ion chromatograph is described together with a matching desalter. This desalter made it possible to use on-line a mass spectrometer. The mass spectrometer enables partly to characterize carbohydrates eluting from the anion exchange column. This separation technology is

  19. Shrew trap efficiency

    DEFF Research Database (Denmark)

    Gambalemoke, Mbalitini; Mukinzi, Itoka; Amundala, Drazo

    2008-01-01

    We investigated the efficiency of four trap types (pitfall, Sherman LFA, Victor snap and Museum Special snap traps) to capture shrews. This experiment was conducted in five inter-riverine forest blocks in the region of Kisangani. The total trapping effort was 6,300, 9,240, 5,280 and 5,460 trap-ni...

  20. A Micro-Cylindrical Ion Trap (B5-CIT) Micro-Mass Spectrometer Instrument System (B5-MSIS) for NASA Planetary Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This activity will significantly increase the fidelity of the miniaturized component packaging of the μ-CIT mass spectrometer assembly. Our design approach...

  1. A Micro-Cylindrical Ion Trap (5-CIT) Micro-Mass Spectrometer Instrument System (5-MSIS) for NASA Planetary Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This activity will significantly increase the fidelity of the miniaturized component packaging of the µ-CIT mass spectrometer assembly. Our design approach...

  2. Determination of Epichlorohydrin in Water by Purge and Trap/Gas Chromatography-Mass Spectrometry%吹扫捕集/气相色谱-质谱联用法测定水中环氧氯丙烷

    Institute of Scientific and Technical Information of China (English)

    张芹; 陈科平; 王少青

    2015-01-01

    A method for determination of epichlorohydrin was established based on purge and trap / gas chromatography mass spectrometry. The purge temperature, purge time, desorption temperature and desorption time were adjusted ,the efficiency of purge and trap affected by purge and trap conditions was analyzed, and the best purge and trap condition were determined. Under the optimized conditions, the correlation coefficients of epichlorohydrin were 0.999 9, the average recoveries were 99.7%, and the relative standard deviations of method were 3.0%; the detection limits of method were 0.10 μg/L. Compared with the national standard method, this method takes advantages of easy to operation, the linear relations, accuracy and precision were well. The method can meet the requirements for the determination of epichlorohydrin in surface water and drinking water.%建立吹扫捕集/气相色谱-质谱法(GC-MS)测定水中环氧氯丙烷的方法。通过对吹扫捕集条件进行调整,讨论吹扫温度和吹扫时间、解吸温度和解吸时间对吹扫捕集效率的影响,确定最佳吹扫捕集条件。结果表明,在最佳条件下,环氧氯丙烷的线性相关系数为0.9999,平均加标回收率为99.7%,相对标准偏差为3.0%;方法检出限为0.10μg/L。该方法与国家标准方法相比,操作简便、检出限低、准确度和精密度高,适用于地表水和生活饮用水中环氧氯丙烷的分析测定。

  3. A purge and trap technique to capture volatile compounds combined with comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry to investigate the effect of sulfur-fumigation on Radix Angelicae Dahuricae.

    Science.gov (United States)

    Cao, Gang; Li, Qinglin; Zhang, Jida; Cai, Hao; Cai, Baochang

    2014-09-01

    Sulfur-fumigation is known to reduce volatile compounds that are the main active components in herbs used in herbal medicine. We investigated changes in chemical composition between sun-dried and sulfur-fumigated Radix Angelicae Dahuricae using a purge and trap technique to capture volatile compounds, and two-dimensional gas chromatography/time-of-flight mass spectrometry for identification. Using sun-dried Radix Angelicae Dahuricae samples as a reference, the results showed that 73 volatile compounds, including 12 sulfide compounds, were found to be present only in sulfur-fumigated samples. Furthermore, 32 volatile compounds that were found in sun-dried Radix Angelicae Dahuricae samples disappeared after sulfur-fumigation. The proposed method can be applied to accurately discriminate sulfur-fumigated Radix Angelicae Dahuricae from different commercial sources.

  4. Simultaneous monitoring of the radial modes of the ion motion and their manipulation in Penning traps by FT-ICR mass spectrometry

    CERN Document Server

    Breitenfeldt, M; Herlert, A; Marxa, G; Schweikhard, L

    2007-01-01

    It is demonstrated how FT-ICR MS can be used to monitor both the coherent magnetron motion and the cyclotron motion of ions stored in a Penning trap. By use of the ICR signal intensity at the magnetron frequency, ν−, and the reduced cyclotron frequency, ν+, the manipulation of the ion motion by dipolar, quadrupolar, and octupolar excitation has been followed. In particular, the conversion between the magnetron and the cyclotron motion by quadrupolar and octupolar excitation at the corresponding resonance frequencies νc = ν+ + ν− and 2νc, respectively, has been observed by detection of the magnetron and the cyclotron signal. While the ion motion under the influence of a quadrupolar excitation has already been studied extensively, the octupolar excitation has been introduced only recently. As compared to other techniques, such as the time-of-flight ion-cyclotron-resonance detection method, FT-ICR MS allows to simultaneously investigate the influence of an excitation on the cyclotron und the magnetron ...

  5. Evaluation of multiple reaction monitoring cubed for the analysis of tachykinin related peptides in rat spinal cord using a hybrid triple quadrupole-linear ion trap mass spectrometer.

    Science.gov (United States)

    Pailleux, Floriane; Beaudry, Francis

    2014-02-01

    Targeted peptide methods generally use HPLC-MS/MRM approaches. Although dependent on the instrumental resolution, interferences may occur while performing analysis of complex biological matrices. HPLC-MS/MRM(3) is a technique, which provides a significantly better selectivity, compared with HPLC-MS/MRM assay. HPLC-MS/MRM(3) allows the detection and quantitation by enriching standard MRM with secondary product ions that are generated within the linear ion trap. Substance P (SP) and neurokinin A (NKA) are tachykinin peptides playing a central role in pain transmission. The objective of this study was to verify whether HPLC-MS/MRM(3) could provide significant advantages over a more traditional HPLC-MS/MRM assay for the quantification of SP and NKA in rat spinal cord. The results suggest that reconstructed MRM(3) chromatograms display significant improvements with the nearly complete elimination of interfering peaks but the sensitivity (i.e. signal-to-noise ratio) was severely reduced. The precision (%CV) observed was between 3.5% and 24.1% using HPLC-MS/MRM and in the range of 4.3-13.1% with HPLC-MS/MRM(3), for SP and NKA. The observed accuracy was within 10% of the theoretical concentrations tested. HPLC-MS/MRM(3) may improve the assay sensitivity to detect difference between samples by reducing significantly the potential of interferences and therefore reduce instrumental errors.

  6. First direct determination of the superallowed β-decay QEC-value for O-14 via Penning trap mass spectrometry at the LEBIT facility

    Science.gov (United States)

    Ringle, Ryan; Bollen, Georg; Brodeur, Maxime; Cooper, Kortney; Eibach, Martin; Gulyuz, Kerim; Izzo, Chris; Morrissey, David; Redshaw, Matthew; Sandler, Rachel; Schwarz, Stefan; Sumithrarachchi, Chandana; Valverde, Adrian; Villari, Antonio

    2016-09-01

    Low-Z, superallowed β-emitters like O-14 are particularly significant for setting limits on the existence of scalar currents in the electroweak interaction. While the Conserved Vector Current (CVC) hypothesis states that Ft should be the same for all superallowed 0 + -> 0 + β -decays, if there is a scalar interaction, an additional term approximately inversely proportional to QEC would be present in Ft. As QEC-values are smaller for lower-Z isotopes, these isotopes would be most sensitive to the presence of a scalar current, showing the largest deviation in Ft. To date, 14 Ft values are used to calculate the world average. Of these 14 decays, only O-14 had not been measured in a Penning trap, despite multiple attempts at other facilities. At LEBIT we have performed the first direct measurement of the ground state β-decay QEC value. This measurement provides an order of magnitude improvement in precision, and it no longer makes a significant contribution to the uncertainty of its associated Ft value. This work was conducted with the support of Michigan State University and the National Science Foundation under Contracts No. PHY-1102511 and No. PHY-1307233.

  7. Analysis of carbonyl compounds via headspace solid-phase microextraction with on-fiber derivatization and gas chromatographic-ion trap tandem mass spectrometric determination of their O-(2,3,4,5,6-pentafluorobenzyl)oxime derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Schmarr, Hans-Georg [Dienstleistungszentrum Laendlicher Raum (DLR) Rheinpfalz, Breitenweg 71, D-67435 Neustadt an der Weinstrasse (Germany)], E-mail: hans-georg.schmarr@dlr.rlp.de; Potouridis, Theodoros; Ganss, Sebastian; Sang, Wei; Koepp, Benedikt; Bokuz, Ursula; Fischer, Ulrich [Dienstleistungszentrum Laendlicher Raum (DLR) Rheinpfalz, Breitenweg 71, D-67435 Neustadt an der Weinstrasse (Germany)

    2008-06-09

    An improved method for the analysis of carbonyls is described utilizing a headspace solid-phase microextraction (HS-SPME) step and on-fiber derivatization with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine (PFBHA) hydrochloride. Thermal desorption of the oxime derivatives formed on the fiber is followed by gas chromatographic separation coupled to an ion trap tandem mass spectrometer (GC-ITMS). Selecting specific fragment ions within the electron ionization (EI{sup +}) mass spectra of these oxime derivatives as precursor ions for MS-MS fragmentation provides a suitable method for the target analysis of individual carbonyl classes, such as alkanals, (E)-2-alkenals, (E,E)-2,4-alkadienals, and others. Retention indices on polar as well as on apolar stationary phases along with EI{sup +} mass spectra patterns are presented for a large set of oxime derivatives, giving valuable information needed for unambiguous assignment of substances in complex sample matrices. The fast sample preparation and derivatization step via HS-SPME can be automated and is applicable to a variety of biological samples and foodstuffs, allowing rapid and sensitive screening analyses of important aldehydic biomarkers and aroma active compounds.

  8. Use of a hand-portable gas chromatograph-toroidal ion trap mass spectrometer for self-chemical ionization identification of degradation products related to O-ethyl S-(2-diisopropylaminoethyl) methyl phosphonothiolate (VX).

    Science.gov (United States)

    Smith, Philip A; Lepage, Carmela R Jackson; Savage, Paul B; Bowerbank, Christopher R; Lee, Edgar D; Lukacs, Michael J

    2011-04-01

    The chemical warfare agent O-ethyl S-(2-diisopropylaminoethyl) methyl phosphonothiolate (VX) and many related degradation products produce poorly diagnostic electron ionization (EI) mass spectra by transmission quadrupole mass spectrometry. Thus, chemical ionization (CI) is often used for these analytes. In this work, pseudomolecular ([M+H](+)) ion formation from self-chemical ionization (self-CI) was examined for four VX degradation products containing the diisopropylamine functional group. A person-portable toroidal ion trap mass spectrometer with a gas chromatographic inlet was used with EI, and both fixed-duration and feedback-controlled ionization time. With feedback-controlled ionization, ion cooling (reaction) times and ion formation target values were varied. Evidence for protonation of analytes was observed under all conditions, except for the largest analyte, bis(diisopropylaminoethyl)disulfide which yielded [M+H](+) ions only with increased fixed ionization or ion cooling times. Analysis of triethylamine-d(15) provided evidence that [M+H](+) production was likely due to self-CI. Analysis of a degraded VX sample where lengthened ion storage and feedback-controlled ionization time were used resulted in detection of [M+H](+) ions for VX and several relevant degradation products. Dimer ions were also observed for two phosphonate compounds detected in this sample.

  9. The Honey Trap

    DEFF Research Database (Denmark)

    Wagner, Michael

    Michael F. Wagner: The Honey Trap –The democratization of leisure through automobilism The automobile has achieved a central position in modern everyday life as an essential artefact to mobility. This raises the question how automobiles have been mediated for mass consumption? The central thesis...... in the article is that the culture of Danish automobilism was constructed around and appropriated through leisure activities conducted primarily by the automobile consumer’s organisation Touring Club de Danemark (FDM). The general purpose for the consumer organisation has been to create a cultural identity...... and a material reality of democratic participation linking ‘Car and Leisure’, a term that has been a central motto for the organization during many decades. The keyword in this activity was ‘Free’ celebrating the manner in which the privately owned automobile secured a maximum of freedom to the owner. The paper...

  10. Tachyon Physics with Trapped Ions

    CERN Document Server

    Lee, Tony E; Cheng, Xiao-Hang; Lamata, Lucas; Solano, Enrique

    2015-01-01

    It has been predicted that particles with imaginary mass, called tachyons, would be able to travel faster than the speed of light. So far, there has not been any experimental evidence for tachyons in either natural or engineered systems. Here, we propose how to experimentally simulate Dirac tachyons with trapped ions. Quantum measurement on a Dirac particle simulated by a trapped ion causes it to have an imaginary mass so that it may travel faster than the effective speed of light. We show that a Dirac tachyon must have spinor-motion entanglement in order to be superluminal. We also show that it exhibits significantly more Klein tunneling than a normal Dirac particle. We provide numerical simulations with realistic ion systems and show that our scheme is feasible with current technology.

  11. St. Croix trap study

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data set contains detailed information about the catch from 600 trap stations around St. Croix. Data fields include species caught, size data, trap location...

  12. Small Mammal Trapping 2003

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Small mammal traps were placed in the Baring division and in the Edmunds division of Moosehom National Wildlife Refuge. There were a total of 98 traps set for up to...

  13. Effect of Pheromone Trap Density on Mass Trapping of Male Potato Tuber Moth Phthorimaea operculella (Zeller (Lepidoptera: Gelechiidae, and Level of Damage on Potato Tubers Efecto de la Densidad de Trampas de Feromona en Masiva de Machos de Polilla de la Papa, Phthorimaea operculella (Zeller (Lepidoptera: Gelechiidae, y en el Nivel de Daño a los Tubérculos

    Directory of Open Access Journals (Sweden)

    Patricia Larraín S

    2009-06-01

    Full Text Available Potato tuber moth (PTM, Phthorimaea operculella (Zeller, is one of the pests that cause the most damage to potatoes (Solanum tuberosum L. in both field crops and storage, especially in regions where summers are hot and dry. Larvae develop in the foliage and tubers of potatoes and cause direct losses of edible product. The use of synthetic pheromones that interfere with insect mating for pest control has been widely demonstrated in numerous Lepidoptera and other insect species. An experiment was carried out during the 2004-2005 season in Valle del Elqui, Coquimbo Region, Chile, to evaluate the effectiveness of different pheromone trap densities to capture P. operculella males for future development of a mass trapping technique, and a subsequent decrease in insect reproduction. The study evaluated densities of 10, 20, and 40 traps ha-1, baited with 0.2 mg of PTM sexual pheromone, and water-detergent for captures. Results indicated that larger numbers of male PTM were captured per trap with densities of 20 and 40 traps per hectare, resulting in a significant reduction (P La polilla de la papa, Phthorimaea operculella (Zeller, es una de las plagas que causan mayor daño a la papa (Solanum tuberosum L., tanto a los cultivos en campo como a los tubérculos almacenados, especialmente en zonas de climas cálidos y secos. Las larvas de este insecto se desarrollan en el follaje y tubérculos de papa causando pérdidas directas del producto a comercializar. La utilización de feromonas sintéticas, como una herramienta que interfiere con el apareamiento, ha sido ampliamente demostrada en innumerables especies de polillas y otros insectos. Con el fin de evaluar la efectividad de diferentes densidades de trampas de feromona en la captura de machos de P. operculella, para su futura utilizacióncomo técnica de trampeo masivo y consecuente disminución de la reproducción del insecto, se realizó un estudio durante la temporada 2004-2005, en el Valle del Elqui

  14. Global Liquidity Trap

    OpenAIRE

    Fujiwara, Ippei; NAKAJIMA Tomoyuki; Sudo, Nao; Teranishi, Yuki

    2011-01-01

    In this paper we consider a two-country New Open Economy Macroeconomics model, and analyze the optimal monetary policy when countries cooperate in the face of a "global liquidity trap" -- i.e., a situation where the two countries are simultaneously caught in liquidity traps. The notable features of the optimal policy in the face of a global liquidity trap are history dependence and international dependence. The optimality of history dependent policy is confirmed as in local liquidity trap. A ...

  15. Ion trap simulation tools.

    Energy Technology Data Exchange (ETDEWEB)

    Hamlet, Benjamin Roger

    2009-02-01

    Ion traps present a potential architecture for future quantum computers. These computers are of interest due to their increased power over classical computers stemming from the superposition of states and the resulting capability to simultaneously perform many computations. This paper describes a software application used to prepare and visualize simulations of trapping and maneuvering ions in ion traps.

  16. Ultra-high performance liquid chromatography with linear ion trap-Orbitrap hybrid mass spectrometry combined with a systematic strategy based on fragment ions for the rapid separation and characterization of components in Stellera chamaejasme extracts.

    Science.gov (United States)

    Wang, Zhixin; Qu, Yang; Wang, Li; Zhang, Xiaozhe; Xiao, Hongbin

    2016-04-01

    Stellera chamaejasme, a famous toxic herb, has been used in traditional Chinese medicine to treat various diseases. For decades, increasing attention in modern pharmacological studies has been drawn to S. chamaejasme because of its potential anti-tumor, anti-virus, and anti-fungus activities. However, due to the intrinsic complexity of chemical constitutes, hardly any investigations formed an overall recognition for the chemical profiles of this herb. In this study, a rapid and sensitive ultra-high performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometry method was developed to characterize the chemical components of S. chamaejasme extracts. Based on optimized ultra-high performance liquid chromatography and mass spectrometry conditions and systematic fragment ions-based strategy, a total of 47 components including flavones, diterpenes, coumarins, and lignans were simultaneously detected and identified or tentatively identified for the first time. The MS(n) fragmentation patterns of all the characterized compounds in positive or negative electrospray ionization modes were also explored and summarized. These results provided essential data for further pharmacological research on S. chamaejasme. Moreover, the method was demonstrated to be an efficient tool for rapid qualitative analysis of secondary metabolites from natural resources.

  17. Metabolic profile of naringenin in the stomach and colon using liquid chromatography/electrospray ionization linear ion trap quadrupole-Orbitrap-mass spectrometry (LC-ESI-LTQ-Orbitrap-MS) and LC-ESI-MS/MS.

    Science.gov (United States)

    Orrego-Lagarón, Naiara; Vallverdú-Queralt, Anna; Martínez-Huélamo, Miriam; Lamuela-Raventos, Rosa M; Escribano-Ferrer, Elvira

    2016-02-20

    Several biological activities (antioxidant, anti-inflammatory, anticarcinogenic) are attributed to naringenin (NAR)-a predominant flavonoid of citrus fruit and tomato-despite its low bioavailability after ingestion. NAR undergoes extensive metabolism when crossing the gastrointestinal tract, resulting in enteric, hepatic and microbial metabolites, some of them with recognized beneficial effects on human health. This study sought to provide new insights into the metabolism of NAR in regions of the gastrointestinal tract where it has been less studied: the stomach and colon. With this purpose, liquid chromatography coupled with an electrospray ionization hybrid linear ion trap quadrupole Orbitrap mass spectrometry technique (LC-ESI-LTQ-Orbitrap-MS) was used for an accurate identification of NAR metabolites, and liquid chromatography/electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) on a triple quadrupole was used for their identification and quantification. The combination of both analytical techniques provided a broader metabolic profile of NAR. As far as we know, this is the first in-depth metabolic profiling study of NAR in the stomach of mice. Three of the metabolites determined using the LC-LTQ-Orbitrap could not be identified by LC-ESI-MS/MS in stomach perfusion samples: apigenin, 3-(4-hydroxyphenyl) propionic acid and phloroglucinol. The number of colonic metabolites determined using the LTQ-Orbitrap-MS was more than twice the number identified by LC-ESI-MS/MS.

  18. Characterization and identification of the chemical constituents from tartary buckwheat (Fagopyrum tataricum Gaertn) by high performance liquid chromatography/photodiode array detector/linear ion trap FTICR hybrid mass spectrometry.

    Science.gov (United States)

    Ren, Qiang; Wu, Caisheng; Ren, Yan; Zhang, Jinlan

    2013-02-15

    In recent years tartary buckwheat has become popular healthful food due to its antioxidant, antidiabetic and antitumor activities. However, its chemical constituents have not yet been fully characterized and identified. In this paper, a novel high performance liquid chromatography coupled with photodiode array detector and linear ion trap FTICR hybrid mass spectrometry (HPLC-PDA/LTQ-FTICRMS) method was established to characterize and identify a total of 36 compounds by a single run. The retention time, maximum UV absorption wavelength, accurate mass weight and characteristic fragment ions were collected on line. To confirm the structures, 11 compounds were isolated and identified by MS and NMR experiments. 1, 3, 6, 6'-tetra-feruloyl sucrose named taroside was a new phenlypropanoid glycoside, together with 3, 6-di-p-coumaroyl-1, 6'-di-feruloyl sucrose, 1, 6, 6'-tri-feruloyl-3-p-coumaroyl sucrose, N-trans-feruloyltyramine and quercetin-3-O-[β-D-xyloxyl-(1→2)-α-L-rhamnoside] were isolated for the first time from the Fagopyrum species. The research enriched the chemical information of tartary buckwheat.

  19. Analysis of emerging contaminants in water and solid samples using high resolution mass spectrometry with a Q Exactive orbital ion trap and estrogenic activity with YES-assay.

    Science.gov (United States)

    Comtois-Marotte, Simon; Chappuis, Thomas; Vo Duy, Sung; Gilbert, Nicolas; Lajeunesse, André; Taktek, Salma; Desrosiers, Mélanie; Veilleux, Éloïse; Sauvé, Sébastien

    2017-01-01

    Trace emerging contaminants (ECs) occur in both waste and surface waters that are rich in particulates that have been found to sorb several organic contaminants. An analytical method based on off-line solid-phase extraction (SPE) followed by liquid chromatography-mass spectrometry (LC-MS) analysis was developed for the detection and quantification of 31 ECs from surface water, wastewater, suspended particulate matter (SPM) as well as sediments. Lyophilized sediments and air-dried SPM were subjected to ultrasonic extraction. Water samples and extracts were then concentrated and cleaned-up by off-line SPE. Quantification was realized using a Q Exactive mass spectrometer in both full scan (FS) and MS(2) modes. These two modes were optimized and compared to determine which one was the most suitable for each matrix studied. Yeast estrogen screen assay (YES-assay) adapted from the direct measurement of estrogenic activity without sample extraction was tested on filtered wastewater samples. An endocrine disrupting effect was detected in all effluent samples analyzed with estradiol equivalent concentrations ranging from 4.4 to 720 ng eq E2 L(-1) for the WWTP-1 and 6.5-42 ng eq E2 L(-1) for the WWTP-2. The analytical methods were also applied on six samples of surface water, the corresponding SPM, the sediments and thirty-nine effluent samples from two wastewater treatment plants (WWTPs) sampled over a period of five months (February to June 2014).

  20. Screening of lysosomal storage disorders: application of the online trapping-and-cleanup liquid chromatography/mass spectrometry method for mucopolysaccharidosis I.

    Science.gov (United States)

    Ombrone, Daniela; Malvagia, Sabrina; Funghini, Silvia; Giocaliere, Elisa; Della Bona, Maria Luisa; Forni, Giulia; De Luca, Alessio; Villanelli, Fabio; Casetta, Bruno; Guerrini, Renzo; la Marca, Giancarlo

    2013-01-01

    In recent years, new treatments have become available to treat some lysosomal storage disorders (LSDs) and many studies suggest that there is a benefit with starting therapy early. Newborn screening should detect diseases early enough for prompt treatment. Some countries include additional conditions, such as some LSDs, into their newborn screening panels. Mucopolysaccharidosis Type I (MPS I) is an autosomal recessive disorder caused by the deficiency of α-L-iduronidase (IDUA) activity. Currently, enzyme replacement therapy (ERT) or bone marrow transplantation is available and this has raised a growing interest for the development of a newborn screening test. In 2009, we reported a new fast and simplified tandem mass spectrometry-based method for quantifying five enzyme activities on dried blood spots. Here, we describe the inclusion of IDUA activity determination for the simultaneous detection of six lysosomal storage diseases. We have defined reference normal ranges by testing 680 healthy newborns and 240 adults. The assay was checked through three confirmed MPS I patients whose IDUA activity was below the normal range. Reproducibility of the assays has been established by assessing the intra-day and inter-day assay imprecisions. This quick assay has been devised to be implemented in newborn screening by liquid chromatography tandem mass spectrometry.

  1. Superconducting microfabricated ion traps

    CERN Document Server

    Wang, Shannon X; Labaziewicz, Jaroslaw; Dauler, Eric; Berggren, Karl; Chuang, Isaac L

    2010-01-01

    We fabricate superconducting ion traps with niobium and niobium nitride and trap single 88Sr ions at cryogenic temperatures. The superconducting transition is verified and characterized by measuring the resistance and critical current using a 4-wire measurement on the trap structure, and observing change in the rf reflection. The lowest observed heating rate is 2.1(3) quanta/sec at 800 kHz at 6 K and shows no significant change across the superconducting transition, suggesting that anomalous heating is primarily caused by noise sources on the surface. This demonstration of superconducting ion traps opens up possibilities for integrating trapped ions and molecular ions with superconducting devices.

  2. LC-ESI-MS/MS法测定人血浆中卢帕他定的浓度%Sensitive liquid chromatography electrospray ionization ion-trap mass spectrometry for the determination of rupatadine in human plasma

    Institute of Scientific and Technical Information of China (English)

    温预关; 喻凌寒; 彭建玲; 廖日房; 马崔

    2007-01-01

    Aim To develop and validate a sensitive and specific liquid chromatography electrospray ionization ion-trap mass spectrometry (LC-ESI-MS/MS) method for the identification and concentration of rupatadine in human plasma. Methods After the addition of the internal standard (IS, loratadine) and 0.01 mol·L-1 sodium hydroxide solution, plasma samples were extracted with methylene chloride: ethyl acetate mixture (20:80, V/V). The organic layer was evaporated under vacuum drying at 37℃. The residue was reconstituted with 200 μL mobile phase. Chromatography was performed on an Agilent Eclipse XDB-C18 (4.6 mm × 150 mm, 5 μm) column with a mobile phase consisting of acetonitrile (1% formic acid) -20 mmol·L-1 ammonium acetate (76:24, V/V) at a flow-rate of 0.6 mL·min-1. Detection was performed on Agilent MSD Trap XCT ion-trap mass spectrometry connected to a Agilent 1100 high performance liquid chromatography (HPLC) by selected reaction monitoring (SRM) mode via electrospray ionization (ESI) source. Rupatadine (MRM m/z 416 → 309) and loratadine (MRM m/z 383→ 337) were detected by Agilent MSD Trap XCT ion-trap mass analyser. Results The method was proved to be sensitive and specific by testing 20 different plasma batches. Linearity was established for the range of concentrations 0.05 - 14.0 ng·mL-1 with a coefficient of determination (r) of 0.998. The intra-and inter-day precision (RSD %) were lower than 15% and accuracy ranged from 85.1% to 114.0%. The lower limit of quantitation (LLOQ) was identifiable and reproducible at 0.05 ng·mL -1 with a precision of 9.22% (n =5). Conclusion The proposed method is sensitive and reproducible enough to be used in pharmacokinetic, bioavailability or bioequivalence studies of rupatadine.%目的 建立测定人血浆中卢帕他定浓度的LC-ESI-MS/MS方法.方法 血浆样品加入内标,碱化后用二氯甲烷:乙酸乙酯(20:80)提取,在37℃真空干燥箱中干燥至干,残渣用200 μL流动相溶解后进样.色谱

  3. Planar Ion Trap Geometry for Microfabrication

    CERN Document Server

    Madsen, M J; Stick, D; Rabchuk, J A; Monroe, C

    2004-01-01

    We describe a novel high aspect ratio radiofrequency linear ion trap geometry that is amenable to modern microfabrication techniques. The ion trap electrode structure consists of a pair of stacked conducting cantilevers resulting in confining fields that take the form of fringe fields from parallel plate capacitors. The confining potentials are modeled both analytically and numerically. This ion trap geometry may form the basis for large scale quantum computers or parallel quadrupole mass spectrometers. PACS: 39.25.+k, 03.67.Lx, 07.75.+h, 07.10+Cm

  4. Characterization of xylazine metabolism in rat liver microsomes using liquid chromatography-hybrid triple quadrupole-linear ion trap-mass spectrometry.

    Science.gov (United States)

    Lavoie, David St-Germain; Pailleux, Floriane; Vachon, Pascal; Beaudry, Francis

    2013-07-01

    Xylazine is an α2 -adrenoceptor agonist and it is widely used in veterinary anesthesia in combination with ketamine. There is limited information on the metabolism of xylazine. A quantitative method for the determination of xylazine by HPLC-ESI/MS/MS was developed. The method consisted of a protein precipitation extraction followed by analysis using liquid chromatography electrospray tandem mass spectrometry. The chromatographic separation was achieved using a Thermo Betasil Phenyl 100 × 2 mm column combined with an isocratic mobile phase composed of acetonitrile, methanol, water and formic acid (60:20:20:0.4) at a flow rate of 300 μL/min. The mass spectrometer was operating in selected reaction monitoring mode and the analytical range was set at 0.05-50 μm. The precision (%CV) and accuracy (%NOM) observed were 2.3-7.2 and 88.2-96.4%. In vitro metabolism studies were performed in rat liver microsomes and results showed moderate cytochrome P450 affinity (Km = 10.1 μm) and a low metabolic stability of xylazine with a half-life of 4.1 min in rat liver microsomes. Five phase 1 metabolites were observed. The main metabolite observed was an oxidation of the thiazine moiety at m/z 235 and, to a lesser extent, we observed the formation of N-(2,6-dimethylphenyl)thiourea at m/z 181 and three distinctive hydroxylated metabolites at m/z 237. Further experiments with ketamine and ketoconazole strongly supported that the metabolism of xylazine to its main metabolite is mediated by CYP3A in rat liver microsomes.

  5. Metabolism of cyadox by the intestinal mucosa microsomes and gut flora of swine, and identification of metabolites by high-performance liquid chromatography combined with ion trap/time-of-flight mass spectrometry.

    Science.gov (United States)

    Xu, Ning; Huang, Lingli; Liu, Zhenli; Pan, Yuanhu; Wang, Xu; Tao, Yanfei; Chen, Dongmei; Wang, Yulian; Peng, Dapeng; Yuan, Zong hui

    2011-08-30

    Cyadox (CYX), 2-formylquinoxaline-1,4-dioxide cyanoacetylhydrazone, is an antimicrobial and growth-promoting feed additive for food-producing animals. To reveal biotransformation of CYX in swine intestine, CYX was incubated with swine intestinal microsomes and mucosa in the presence of an NADPH-generating system and swine ileal flora and colonic flora, respectively. The metabolites of CYX were identified using high-performance liquid chromatography combined with ion trap/time-of-flight mass spectrometry (LC/MS-ITTOF). Structural elucidation of the metabolites was precisely performed by comparing their changes in molecular mass, full scan MS/MS spectra and accurate mass measurements with those of the parent drug. Finally, seven metabolites were identified as follows: three reduced metabolites (cyadox 1-monoxide (Cy1), cyadox 4-monoxide (Cy2) and bisdesoxycyadox (Cy4)); hydroxylation metabolite (3-hydroxylcyadox 1-monoxide (Cy3)); hydrolysis metabolite of the amide bond (N-decyanoacetyl cyadox (Cy5)); a hydrogenation metabolite (11,12-dihydro-bisdesoxycyadox (Cy6)) and a side-chain cleavage metabolite (2-hydromethylquinoxaline (Cy7)). Only one metabolite (Cy1) was found in intestinal microsomes. Cy1, Cy2 and Cy4 were detected in intestinal mucosa, ileal and colonic flora. In addition, Cy3 and Cy5 were only obtained from ileal flora, and Cy6 and Cy7 alone were observed in colonic bacteria. The results indicated that N→O group reduction was the main metabolic pathway of CYX metabolism in swine ileal flora, intestinal microsomes and mucosa. New metabolic profiles of hydrogenation and cleavage on the side chain were found in colonic bacteria. Among the identified metabolites, two new metabolites (Cy6, Cy7) were detected for the first time. These studies will contribute to clarify comprehensively the metabolism of CYX in animals, and provide evidence to explain the pharmacology and toxicology effects of CYX in animals.

  6. Thermal dissociation atmospheric chemical ionization ion trap mass spectrometry with a miniature source for selective trace detection of dimethoate in fruit juices.

    Science.gov (United States)

    Ouyang, Yongzhong; Zhang, Xinglei; Han, Jing; Guo, Xiali; Zhu, Zhiqiang; Chen, Huanwen; Luo, Liping

    2013-01-21

    A miniature thermal dissociation atmospheric chemical ionization (TDCI) source, coupled with LTQ-MS, has been developed for rapid trace detection of pesticide residues such as dimethoate in highly viscous fruit juice samples. Instead of toxic organic solvents and the high electric field used in the conventional ionizations, an ionic liquid, a "green solvent", was employed to directly generate reagent ions in the TDCI process, followed by the proton or charge transfer with the analytes prior to the LTQ instrument for mass analysis. Trace amounts of dimethoate in fresh orange juices have been quantitatively detected, without any sample pretreatment or aid of high-pressure gas. A low limit of detection (LOD = 8.76 × 10(-11) g mL(-1)), acceptable relative standard deviation (RSD = 3.1-10.0%), and reasonable recoveries (91.2-102.8%) were achieved with this method for direct detection of dimethoate in highly viscous orange juice samples. The average analysis time for each single sample was less than 30 seconds. These experimental results showed that the miniature TDCI developed here is a powerful tool for the fast trace detection of pesticide residues in complex viscous fruit juices, with the advantage of high sensitivity, high speed, and high-throughput, ease of operation, and so on. Because of no chemical contamination and high voltage damage to the analytes and the environment, the technique has promising applications for online quality monitoring in the area of food safety.

  7. Development of an in-line HPLC fingerprint ion-trap mass spectrometric method for identification and quality control of Radix Scrophulariae.

    Science.gov (United States)

    Jing, Jing; Chan, Chi-on; Xu, Lijia; Jin, Dengping; Cao, Xinwei; Mok, Daniel K W; Parekh, H S; Chen, Sibao

    2011-12-05

    Chromatographic fingerprinting has been widely accepted as a crucial method for qualitative and quantitative analyses of bioactives within traditional Chinese medicine. A fingerprint provides detailed information, specific for any given herb, thus facilitating the quality control measures of a given traditional Chinese medicine. In this article, quality assessment of Radix Scrophulariae was achieved by using high performance liquid chromatography combining diode-array detection and electrospray ionization mass spectrometry (HPLC-DAD-ESI/MS). Eight batches of sample obtained from different origins in China were used to establish the fingerprint and quantitative analyses. By comparing the retention times, UV and MS spectral data with reference standards, four characteristic peaks in the chromatograms were confirmed as corresponding to acetoside, angoroside C, cinnamic acid, and harpagoside. In addition, other two characteristic peaks were tentatively identified, following the literature interpretation of HPLC-ESI-MS and LC-MS/MS (affording structural information) to be sibirioside A and scrophuloside B(4), respectively. The results indicated that the newly developed HPLC-DAD-MS fingerprint method would be suitable for quality control of Radix Scrophulariae.

  8. Metabolism studies of the Kratom alkaloid speciociliatine, a diastereomer of the main alkaloid mitragynine, in rat and human urine using liquid chromatography-linear ion trap mass spectrometry.

    Science.gov (United States)

    Philipp, Anika A; Wissenbach, Dirk K; Weber, Armin A; Zapp, Josef; Maurer, Hans H

    2011-03-01

    Mitragyna speciosa (Kratom) is currently used as a drug of abuse. When monitoring its abuse in urine, several alkaloids and their metabolites must be considered. In former studies, mitragynine (MG), its diastereomer speciogynine (SG), and paynantheine and their metabolites could be identified in rat and human urine using LC-MS(n). In Kratom users' urines, besides MG and SG, further isomeric compounds were detected. To elucidate whether the MG and SG diastereomer speciociliatine (SC) and its metabolites represent further compounds, the phase I and II metabolites of SC were identified first in rat urine after the administration of the pure alkaloid. Then, the identified rat metabolites were screened for in the urine of Kratom users using the above-mentioned LC-MS(n) procedure. Considering the mass spectra and retention times, it could be confirmed that SC and its metabolites are so far the unidentified isomers in human urine. In conclusion, SC and its metabolites can be used as further markers for Kratom use, especially by consumption of raw material or products that contain a high amount of fruits of the Malaysian plant M. speciosa.

  9. Characterization of Proanthocyanidins from Parkia biglobosa (Jacq. G. Don. (Fabaceae by Flow Injection Analysis — Electrospray Ionization Ion Trap Tandem Mass Spectrometry and Liquid Chromatography/Electrospray Ionization Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Wagner Vilegas

    2013-03-01

    Full Text Available The present study investigates the chemical composition of the African plant Parkia biglobosa (Fabaceae roots and barks by Liquid Chromatography - Electrospray Ionization and Direct Injection Tandem Mass Spectrometry analysis. Mass spectral data indicated that B-type oligomers are present, namely procyanidins and prodelphinidins, with their gallate and glucuronide derivatives, some of them in different isomeric forms. The analysis evidenced the presence of up to 40 proanthocyanidins, some of which are reported for the first time. In this study, the antiradical activity of extracts of roots and barks from Parkia biglobosa was evaluated using DPPH method and they showed satisfactory activities.

  10. Characterization of proanthocyanidins from Parkia biglobosa (Jacq.) G. Don. (Fabaceae) by Flow Injection Analysis-Electrospray Ionization Ion Trap Tandem Mass Spectrometry and Liquid Chromatography/Electrospray Ionization Mass Spectrometry.

    Science.gov (United States)

    Tala, Viviane Raïssa Sipowo; Candida da Silva, Viviane; Rodrigues, Clenilson Martins; Nkengfack, Augustin Ephrem; dos Santos, Lourdes Campaner; Vilegas, Wagner

    2013-03-01

    The present study investigates the chemical composition of the African plant Parkia biglobosa (Fabaceae) roots and barks by Liquid Chromatography-Electrospray Ionization and Direct Injection Tandem Mass Spectrometry analysis. Mass spectral data indicated that B-type oligomers are present, namely procyanidins and prodelphinidins, with their gallate and glucuronide derivatives, some of them in different isomeric forms. The analysis evidenced the presence of up to 40 proanthocyanidins, some of which are reported for the first time. In this study, the antiradical activity of extracts of roots and barks from Parkia biglobosa was evaluated using DPPH method and they showed satisfactory activities.

  11. Trap style influences wild pig behavior and trapping success

    Science.gov (United States)

    Williams, B.L.; Holtfreter, R.W.; Ditchkoff, S.S.; Grand, J.B.

    2011-01-01

    Despite the efforts of many natural resource professionals, wild pig (Sus scrofa) populations are expanding in many areas of the world. Although many creative techniques for controlling pig populations are being explored, trapping has been and still is themost commonly usedmethod of population control formany public and private land managers. We conducted an observational study to examine the efficiency of 2 frequently used trap styles: a small, portable box-style trap and a larger, semi-permanent, corral-style trap.We used game cameras to examine patterns of trap entry by wild pigs around each style of trap, and we conducted a trapping session to compare trapping success between trap styles. Adult female and juvenile wild pigs entered both styles of trap more readily than did adult males, and adult males seemed particularly averse to entering box traps. Less than 10% of adult male visits to box traps resulted in entries, easily the least percentage of any class at any style of trap. Adult females entered corral traps approximately 2.2 times more often per visit than box traps and re-entered corral traps >2 times more frequently. Juveniles entered and reentered both box and corral traps at similar rates. Overall (all-class) entry-per-visit rates at corral traps (0.71) were nearly double that of box traps (0.37). Subsequent trapping data supported these preliminary entry data; the capture rate for corral traps was >4 times that of box traps. Our data suggest that corral traps are temporally and economically superior to box traps with respect to efficiency; that is, corral traps effectively trap more pigs per trap night at a lower cost per pig than do box traps. ?? 2011 The Wildlife Society.

  12. Fundamental physics in particle traps

    CERN Document Server

    Vogel, Manuel

    2014-01-01

    This volume provides detailed insight into the field of precision spectroscopy and fundamental physics with particles confined in traps. It comprises experiments with electrons and positrons, protons and antiprotons, antimatter and highly charged ions, together with corresponding theoretical background. Such investigations represent stringent tests of quantum electrodynamics and the Standard model, antiparticle and antimatter research, test of fundamental symmetries, constants, and their possible variations with time and space. They are key to various aspects within metrology such as mass measurements and time standards, as well as promising to further developments in quantum information processing. The reader obtains a valuable source of information suited for beginners and experts with an interest in fundamental studies using particle traps.

  13. Experimental demonstration of a surface-electrode multipole ion trap

    CERN Document Server

    Maurice, Mark; Green, Dylan; Farr, Andrew; Burke, Timothy; Hilleke, Russell; Clark, Robert

    2015-01-01

    We report on the design and experimental characterization of a surface-electrode multipole ion trap. Individual microscopic sugar particles are confined in the trap. The trajectories of driven particle motion are compared with a theoretical model, both to verify qualitative predictions of the model, and to measure the charge-to-mass ratio of the confined particle. The generation of harmonics of the driving frequency is observed as a key signature of the nonlinear nature of the trap. We remark on possible applications of our traps, including to mass spectrometry.

  14. Biotransformation and metabolic profile of buddleoside with human intestinal microflora by ultrahigh-performance liquid chromatography coupled to hybrid linear ion trap/orbitrap mass spectrometer.

    Science.gov (United States)

    Tao, Jin-Hua; Duan, Jin-Ao; Jiang, Shu; Qian, Yi-Yun; Qian, Da-Wei

    2016-07-01

    Buddleoside (also known as linarin) as the major flavonoid in Chrysanthemum morifolium Ramat., has been reported to possess a wide range of pharmacological activities. The human intestinal microbiota might have an important impact on drug metabolism and ultimately on the drug oral bioavailability. However, the interaction of the buddleoside with human intestinal bacteria remains unknown. In this study, the conversion of buddleoside by different bacteria from human feces was firstly investigated. A reliable, sensitive and rapid analytical method, ultra performance liquid chromatography was established and successfully applied to investigate the metabolites and metabolic profile of buddleoside by human intestinal bacteria. Among the isolated bacteria, four strains including Escherichia sp. 4, Escherichia sp. 34, Enterococcus sp. 45 and Bacillus sp. 46 showed more powerful conversion capability. Based on the accurate mass data and the characteristic MS(n) product ions, the parent and six metabolites were detected and tentatively identified compared with blank samples. The metabolites were produced by four main metabolic pathways including deglycosylation, acetylation, methylation and hydroxylation. Buddleoside could be firstly converted to its aglycon acacetin (M2) by the majority of the isolated intestinal bacteria. Subsequently, M2 was further metabolize to its methylated (M3), acetylated (M4), hydroxylated (M5) and hydrogenated product (M6). However, acacetin-7-glucosid (M1) was obtained only from the minor bacterial samples like Bacillus sp. 46. To further explain the metabolism of buddleoside, the β-d-glucosidase and α-l-rhamnosidase activities of four strains were analyzed. Bacillus sp. 46 could only produce α-l-rhamnosidase, while the other three strains showed two kinds of enzyme activities. Furthermore, the activities of α-l-rhamnosidase and β-d-glucosidase reached the highest level at 12-18h and 10-12h, respectively. The metabolic routes and metabolites

  15. Online trapping and enrichment ultra performance liquid chromatography-tandem mass spectrometry method for sensitive measurement of 'arginine-asymmetric dimethylarginine cycle' biomarkers in human exhaled breath condensate

    Energy Technology Data Exchange (ETDEWEB)

    Di Gangi, Iole Maria, E-mail: giordano@pediatria.unipd.it [Chromatography and Mass Spectrometry Laboratory, Department of Women' s and Children' s Health, University of Padova (Italy); Pirillo, Paola [Chromatography and Mass Spectrometry Laboratory, Department of Women' s and Children' s Health, University of Padova (Italy); Carraro, Silvia [Unit of Allergy and Respiratory Diseases, Department of Women' s and Children' s Health, University of Padova (Italy); Gucciardi, Antonina; Naturale, Mauro [Chromatography and Mass Spectrometry Laboratory, Department of Women' s and Children' s Health, University of Padova (Italy); Baraldi, Eugenio [Unit of Allergy and Respiratory Diseases, Department of Women' s and Children' s Health, University of Padova (Italy); Giordano, Giuseppe [Chromatography and Mass Spectrometry Laboratory, Department of Women' s and Children' s Health, University of Padova (Italy)

    2012-11-19

    Highlights: Black-Right-Pointing-Pointer Simultaneous quantification of 'arginine-ADMA cycle' metabolites developed in EBC. Black-Right-Pointing-Pointer EBC is a non-invasive matrix highly useful in patients with respiratory diseases. Black-Right-Pointing-Pointer Method, fast, precise and accurate, is suitable in the pediatric clinical studies. Black-Right-Pointing-Pointer Sensitivity is increased using on-line trapping and enrichment-UPLC-MS/MS method. Black-Right-Pointing-Pointer EBC measurements in asthmatic adolescents confirm that ADMA is increased in asthma. - Abstract: Background: Exhaled breath condensate (EBC) is a biofluid collected non invasively that, enabling the measurement of several biomarkers, has proven useful in the study of airway inflammatory diseases, including asthma, COPD and cystic fibrosis. To the best of our knowledge, there is no previous report of any analytical method to detect ADMA in EBC. Objectives: Aim of this work was to develop an online sample trapping and enrichment system, coupled with an UPLC-MS/MS method, for simultaneous quantification of seven metabolites related to 'Arginine-ADMA cycle', using the isotopic dilution. Methods: Butylated EBC samples were trapped in an online cartridge, washed before and after each injection with cleanup solution to remove matrix components and switched inline into the high pressure analytical column. Multiple reaction monitoring in positive mode was used for analyte quantification by tandem mass spectrometry. Results: Validation studies were performed in EBC to examine accuracy, precision and robustness of the method. For each compound, the calibration curves showed a coefficient of correlation (r{sup 2}) greater than 0.992. Accuracy (%Bias) was <3% except for NMMA and H-Arg (<20%), intra- and inter-assay precision (expressed as CV%) were within {+-}20% and recovery ranged from 97.1 to 102.8% for all analytes. Inter-day variability analysis on 20 EBC of adult subjects did

  16. Poly-anion production in Penning and RFQ ion traps

    Energy Technology Data Exchange (ETDEWEB)

    Bandelow, Steffi; Martinez, Franklin; Marx, Gerrit; Schweikhard, Lutz [Institute for Physics, Ernst-Moritz-Arndt University, 17487 Greifswald (Germany)

    2014-07-01

    The poly-anion production is being investigated in Penning and linear radio-frequency quadrupole (RFQ) traps at the ClusterTrap setup. The range of anionic charge states produced with the electron-bath technique in a Penning trap is restricted by the upper mass limit of this trap. By installation of a cylindrical Penning trap with a 12-Tesla superconducting magnet, the mass and thus cluster-size range is enhanced by a factor of 20 compared to the previously used hyperbolic 5-Tesla Penning trap. For first experimental tests with the 12-Tesla cylindrical Penning trap, gold cluster mono-anions Au{sup n-1}, n=330-350, have been exposed to an electron bath. As a result, higher negative charge states up to hexa-anionic clusters have been observed for the first time. In a parallel effort, di- and tri-anionic gold clusters have been produced in an RFQ-trap. To this end, an electron beam is guided through the RFQ-trap, which is operated by 2- or 3-state digital driving voltages. In addition, both polyanion-production techniques have been combined by pre-charging clusters in the RFQ-trap, transferring the resulting dianions into the Penning trap and applying the electron-bath technique to produce higher charge states.

  17. Simultaneous determination of 24 or more acidic and alkaline phytohormones in femtomole quantities of plant tissues by high-performance liquid chromatography-electrospray ionization-ion trap mass spectrometry.

    Science.gov (United States)

    Liu, Shichang; Chen, Weiqi; Qu, Long; Gai, Ying; Jiang, Xiangning

    2013-02-01

    Phytohormones act at relatively low concentrations as major regulatory factors of plant growth and development, and cross talk of phytohormones is currently of great interest throughout the plant science community. To meet this demand, a method that is capable of simultaneously analyzing diverse plant hormones is essential. This paper introduces a high-performance liquid chromatographic separation technique coupled with sensitive and selective ion trap mass spectrometry to simultaneously determine 24 or more acidic and alkaline phytohormones, including auxin, cis- and trans-abscisic acid, 11 cytokinins, and 10 gibberellins, in a single injection of sample. A binary solid-phase extraction using Oasis MCX cartridges for cations and Oasis MAX cartridges for anions was used to prepurify more than 24 acidic and alkaline phytohormones from a single plant extract. The method showed good linearity for all 24 phytohormones with R(2) values ranging from 0.9903 to 0.9997. Limits of detection for most of the phytohormones were in the femtomole range with some extending into the sub-femtomole range. This method was applied to hundreds of plant samples comprising different tissues from various plants, including herbaceous, woody climbing, and woody plants to demonstrate feasibility and to validate the methodology.

  18. Simultaneous Qualitative and Quantitative Analysis of Multiple Chemical Constituents in YiQiFuMai Injection by Ultra-Fast Liquid Chromatography Coupled with Ion Trap Time-of-Flight Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Chunhua Liu

    2016-05-01

    Full Text Available YiQiFuMai injection (YQFM is a modern lyophilized powder preparation derived from the traditional Chinese medicine Sheng-mai san (SMS used for treating cardiovascular diseases, such as chronic heart failure. However, its chemical composition has not been fully elucidated, particularly for the preparation derived from Ophiopogon japonicus. This study aimed to establish a systematic and reliable method to quickly and simultaneously analyze the chemical constituents in YQFM by ultra-fast liquid chromatography coupled with ion trap time-of-flight mass spectrometry (UFLC-IT-TOF/MS. Sixty-five compounds in YQFM were tentatively identified by comparison with reference substances or literature data. Furthermore, twenty-one compounds, including three ophiopogonins, fifteen ginsenosides and three lignans were quantified by UFLC-IT-TOF/MS. Notably, this is the first determination of steroidal saponins from O. japonicus in YQFM. The relative standard deviations (RSDs of intra- and inter-day precision, reproducibility and stability were <4.9% and all analytes showed good linearity (R2 ≥ 0.9952 and acceptable recovery of 91.8%–104.2% (RSD ≤ 5.4%, indicating that the methods were reliable. These methods were successfully applied to quantitative analysis of ten batches of YQFM. The developed approach can provide useful and comprehensive information for quality control, further mechanistic studies in vivo and clinical application of YQFM.

  19. A strategy for comprehensive identification of sequential constituents using ultra-high-performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometer, application study on chlorogenic acids in Flos Lonicerae Japonicae.

    Science.gov (United States)

    Zhang, Jia-yu; Wang, Zi-jian; Li, Yun; Liu, Ying; Cai, Wei; Li, Chen; Lu, Jian-qiu; Qiao, Yan-jiang

    2016-01-15

    The analytical methodologies for evaluation of multi-component system in traditional Chinese medicines (TCMs) have been inadequate or unacceptable. As a result, the unclarity of multi-component hinders the sufficient interpretation of their bioactivities. In this paper, an ultra-high-performance liquid chromatography coupled with linear ion trap-Orbitrap (UPLC-LTQ-Orbitrap)-based strategy focused on the comprehensive identification of TCM sequential constituents was developed. The strategy was characterized by molecular design, multiple ion monitoring (MIM), targeted database hits and mass spectral trees similarity filter (MTSF), and even more isomerism discrimination. It was successfully applied in the HRMS data-acquisition and processing of chlorogenic acids (CGAs) in Flos Lonicerae Japonicae (FLJ), and a total of 115 chromatographic peaks attributed to 18 categories were characterized, allowing a comprehensive revelation of CGAs in FLJ for the first time. This demonstrated that MIM based on molecular design could improve the efficiency to trigger MS/MS fragmentation reactions. Targeted database hits and MTSF searching greatly facilitated the processing of extremely large information data. Besides, the introduction of diagnostic product ions (DPIs) discrimination, ClogP analysis, and molecular simulation, raised the efficiency and accuracy to characterize sequential constituents especially position and geometric isomers. In conclusion, the results expanded our understanding on CGAs in FLJ, and the strategy could be exemplary for future research on the comprehensive identification of sequential constituents in TCMs. Meanwhile, it may propose a novel idea for analyzing sequential constituents, and is promising for quality control and evaluation of TCMs.

  20. Multiresidue analysis of 36 pesticides in soil using a modified quick, easy, cheap, effective, rugged, and safe method by liquid chromatography with tandem quadruple linear ion trap mass spectrometry.

    Science.gov (United States)

    Feng, Xue; He, Zeying; Wang, Lu; Peng, Yi; Luo, Ming; Liu, Xiaowei

    2015-09-01

    A new method for simultaneous determination of 36 pesticides, including 15 organophosphorus, six carbamate, and some other pesticides in soil was developed by liquid chromatography with tandem quadruple linear ion trap mass spectrometry. The extraction and clean-up steps were optimized based on the quick, easy, cheap, effective, rugged, and safe method. The data were acquired in multiple reaction monitoring mode combined with enhanced product ion to increase confidence of the analytical results. Validation experiments were performed in soil samples. The average recoveries of pesticides at four spiking levels (1, 5, 50, and 100 μg/kg) ranged from 63 to 126% with relative standard deviation below 20%. The limits of detection of pesticides were 0.04-0.8 μg/kg, and the limits of quantification were 0.1-2.6 μg/kg. The correlation coefficients (r(2) ) were higher than 0.990 in the linearity range of 0.5-200 μg/L for most of the pesticides. The method allowed for the analysis of the target pesticides in the lower μg/kg concentration range. The optimized method was then applied to the test of real soil samples obtained from several areas in China, confirming the feasibility of the method.

  1. Determination of sulfonamide antibiotics and metabolites in liver, muscle and kidney samples by pressurized liquid extraction or ultrasound-assisted extraction followed by liquid chromatography-quadrupole linear ion trap-tandem mass spectrometry (HPLC-QqLIT-MS/MS).

    Science.gov (United States)

    Hoff, Rodrigo Barcellos; Pizzolato, Tânia Mara; Peralba, Maria do Carmo Ruaro; Díaz-Cruz, M Silvia; Barceló, Damià

    2015-03-01

    Sulfonamides are widely used in human and veterinary medicine. The presence of sulfonamides residues in food is an issue of great concern. Throughout the present work, a method for the targeted analysis of 16 sulfonamides and metabolites residue in liver of several species has been developed and validated. Extraction and clean-up has been statistically optimized using central composite design experiments. Two extraction methods have been developed, validated and compared: i) pressurized liquid extraction, in which samples were defatted with hexane and subsequently extracted with acetonitrile and ii) ultrasound-assisted extraction with acetonitrile and further liquid-liquid extraction with hexane. Extracts have been analyzed by liquid chromatography-quadrupole linear ion trap-tandem mass spectrometry. Validation procedure has been based on the Commission Decision 2002/657/EC and included the assessment of parameters such as decision limit (CCα), detection capability (CCβ), sensitivity, selectivity, accuracy and precision. Method׳s performance has been satisfactory, with CCα values within the range of 111.2-161.4 µg kg(-1), limits of detection of 10 µg kg(-1) and accuracy values around 100% for all compounds.

  2. Suitability of a magnetic particle immunoassay for the analysis of PBDEs in Hawaiian euryhaline fish and crabs in comparison with gas chromatography/electron capture detection-ion trap mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Xu Ting [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, 1955 East-West Road, Honolulu, HI 96822 (United States); Cho, Il Kyu; Wang Dongli [Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, 1955 East-West Road, Honolulu, HI 96822 (United States); Rubio, Fernando M. [Abraxis LLC, 54 Steamwhistle Drive, Warminster, PA 18974 (United States); Shelver, Weilin L. [USDA-ARS Biosciences Research Laboratory, 1605 Albrecht Boulevard, Fargo, ND 58105 (United States); Gasc, Anne M.E. [Encore, Inc., P.O. Box 47, Waimanalo, HI 96795-0047 (United States); Li, Ji [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); Li, Qing X. [Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, 1955 East-West Road, Honolulu, HI 96822 (United States)], E-mail: qingl@hawaii.edu

    2009-02-15

    A gas chromatograph/electron capture detector-ion trap mass spectrometer (GC/ECD-ITMS) was used for the determination of polybrominated diphenyl ethers (PBDEs) in euryhaline fish and crabs. GC/ECD-ITMS results showed that average recoveries from the spiked fish samples are in a range of 58-123% with relative standard deviations (RSDs) of 5-19%. PBDE concentrations obtained from GC/ECD-ITMS ranged from 28 ng/g to 1845 ng/g lipid weight (lw) in all aquatic species collected from Hawaiian brackish waters. The general BDE congener concentration profile observed in this study is BDE-47 > BDE-100 > BDE-154 > BDE-99 > BDE-153 > BDE-28 > BDE-183. The ELISA results expressed as BDE-47 equivalents correlated well with those of GC/ECD-ITMS, with a correlation coefficient (R{sup 2} = 0.68) and regression coefficient (slope = 0.82). Comparison of ELISA with GC/ECD-ITMS results demonstrated that ELISA provides a timely and cost-effective method to screen PBDEs in fish and crab samples. - PBDEs (with the most abundant being BDE-47) at concentrations of 28-1845 ng/g lipid weight in fish and crabs from Hawaiian freshwater were detected with both ELISA and GC/MS.

  3. Metabolism studies of the Kratom alkaloids mitraciliatine and isopaynantheine, diastereomers of the main alkaloids mitragynine and paynantheine, in rat and human urine using liquid chromatography-linear ion trap-mass spectrometry.

    Science.gov (United States)

    Philipp, Anika A; Wissenbach, Dirk K; Weber, Armin A; Zapp, Josef; Maurer, Hans H

    2011-05-01

    Mitragyna speciosa (Kratom in Thai), native in Southeast Asia, is increasingly misused as a herbal drug of abuse. During metabolism studies on the Kratom alkaloids mitragynine, its diastereomers speciogynine and speciociliatine as well as paynantheine in rats and humans, further isomeric compounds were detected in Kratom users' urine. The question arose whether these compounds were formed from the low abundant, isomeric alkaloids mitraciliatine (MC) and isopaynantheine (ISO-PAY). Therefore, the aim of the presented study was to identify using liquid chromatography-linear ion trap-mass spectrometry their phase I and II metabolites in rat urine after administration of pure MC or ISO-PAY, to confirm their formation in humans, and finally to confirm whether the above-mentioned isomeric compounds in human urine represent MC and ISO-PAY and/or their metabolites. The metabolic pathways of both alkaloids in rats were found to be comparable to those of their corresponding diastereomers. In the human urines tested, not all metabolites found in rats could be detected because of the much lower amounts of MC and ISO-PAY in Kratom. However, all the above-mentioned so far unknown isomeric compounds could be identified in the human urine samples as MC, ISO-PAY and/or their metabolites. The used LC separation was also suitable for the differentiation of all other Kratom alkaloids and their metabolites in human urine.

  4. Rapid and simple determination of acrylamide in conventional cereal-based foods and potato chips through conversion to 3-[bis(trifluoroethanoyl)amino]-3-oxopropyl trifluoroacetate by gas chromatography coupled with electron capture and ion trap mass spectrometry detectors.

    Science.gov (United States)

    Russo, Mario Vincenzo; Avino, Pasquale; Centola, Angela; Notardonato, Ivan; Cinelli, Giuseppe

    2014-03-01

    A new, simple, rapid and fully validated method based on gas chromatography coupled with Electron capture and ion trap mass spectrometry detectors (GC-ECD and GC-IT/MS) is presented for quantitative analysis of acrylamide contaminant in conventional cereal-based foods and potato chips. Before analysis acrylamide was efficiently derivatized with trifluoroacetic anhydride, the effects of temperature, reaction time and catalyst on the acylation reaction were evaluated. Chromatographic analysis was performed on SE-54 capillary column; good retention and peak response of the acrylamide derivative achieved under the optimal conditions. The analytical method has been fully validated by assessment of the following parameters: LODs and LOQs (1 and 25ngg(-1) by GC-ECD and 2 and 36ngg(-1) by GC-IT/MS, with a Relative Standard Deviations acrylamide spiked at levels of 1, 20, 50 and 100ngg(-1)). Furthermore, the method proposed requires no clean-up step of the acrylamide derivative to be performed prior to injection. The developed method has been successfully applied to determine acrylamide in different commercial cereal-based foods (including French fries and potato chips).

  5. Qualitative and Quantitative Assessments of Aconiti Lateralis Radix Praeparata Using High-Performance Liquid Chromatography Coupled with Diode Array Detection and Hybrid Ion Trap-Time-of-Flight Mass Spectrometry.

    Science.gov (United States)

    Zhang, Na; Song, Yuelin; Song, Qingqing; Shi, Shepo; Zhang, Qian; Zhao, Yunfang; Li, Jun; Tu, Pengfei

    2016-07-01

    Dual roles have been widely disclosed for Aconiti Lateralis Radix Praeparata (Chinese name: Fuzi) by acting as an effective herbal medicine accompanied with high toxicity risk and narrow therapeutic range. Aconite alkaloids, also known as diterpenoid alkaloids (DAs), have been proved to be primary therapeutic as well as toxic material basis of Fuzi. In the present study, we aim to characterize qualitative profile along with quantitative features of DAs in Fuzi, which could benefit the quality control of Fuzi as well as its safe medication in clinic. Chromatographic fingerprinting was achieved using 12 batches of crude materials collected from different habitats (similarities >0.9) by hyphenating liquid chromatography (LC) with diode array detection. Simultaneous determination of six primary DAs, namely benzoylmesaconine, benzoylaconine, benzoylhypaconine, mesaconine, aconitine and hypaconitine, was also carried out. The developed method was systematically validated and successfully applied for quantitative characterization. Significant variations were observed regarding the contents of those six analytes among different raw materials. A total of 99 DAs were detected and characterized, including 9 unambiguous identities and 77 putative assignments, as well as 13 unknown compounds, from the representative extract by LC coupled with hybrid ion trap-time-of-flight mass spectrometry. The findings obtained herein could favor in-depth understanding of the chemical composition of DAs and the quality control of Fuzi.

  6. Identification of the metabolites of biologically active xanthones isolated from Halenia elliptica D.Don by high performance liquid chromatography coupled to ion trap time-of-flight mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    Ru Feng; Jian Gong Shi; Xiao Wei Liu; Chun Tao Che; John H.K. Yeung; Yan Wang

    2011-01-01

    Metabolism study has been carried out on l-hydroxy-2,3,5-trimethoxyxanthone (HM-1) and l-hydroxy-2,3,4,7-tetramethoxyxanthone (HM-2), which are two biologically active ingredients isolated from the Tibetan herb, Halenia elliptica D. Don., in rat liver microsomes in vitro. A method of high performance liquid chromatography coupled to ion trap time-of-flight mass spectrometry (LCMSn-ESI-IT-TOF) was applied to analyze metabolites of HM-1 and HM-2 on line, and five metabolites were identified containing l,5-dihydroxy-2,3-dimethoxyxanthone (HM-5), l,7-dihydroxy-2,3,4-trimethoxyxanthone (HM-9), 1,4, 7-trihydroxy-2,3-dimethoxyxanthone (HM-10), l,4-dihydroxy-2,3,7-trimethoxyxanthone (HM-11) and l,2-dihydroxy-3,4,7-trimethoxyxanthone (HM-12). Among these metabolites, HM-9, HM-11, and HM-12 were isomers mutually. The results indicated that HM-1 and HM-2 occurred Phase I metabolic reaction of demethylation in rat microsomes in vitro.

  7. Towards trapped antihydrogen

    CERN Document Server

    Jorgensen, L V; Bertsche, W; Boston, A; Bowe, P D; Cesar, C L; Chapman, S; Charlton, M; Fajans, J; Fujiwara, M C; Funakoshi, R; Gill, D R; Hangst, J S; Hayano, R S; Hydomako, R; Jenkins, M J; Kurchaninov, L; Madsen, N; Nolan, P; Olchanski, K; Olin, A; Page, R D; Povilus, A; Robicheaux, F; Sarid, E; Silveira, D M; Storey, J W; Thompson, R I; van der Werf, D P; Wurtele, J S; Yamazaki, Y

    2008-01-01

    Substantial progress has been made in the last few years in the nascent field of antihydrogen physics. The next big step forward is expected to be the trapping of the formed antihydrogen atoms using a magnetic multipole trap. ALPHA is a new international project that started to take data in 2006 at CERN’s Antiproton Decelerator facility. The primary goal of ALPHA is stable trapping of cold antihydrogen atoms to facilitate measurements of its properties. We discuss the status of the ALPHA project and the prospects for antihydrogen trapping.

  8. Approach to the study of flavone di-C-glycosides by high performance liquid chromatography-tandem ion trap mass spectrometry and its application to characterization of flavonoid composition in Viola yedoensis.

    Science.gov (United States)

    Cao, Jie; Yin, Chengle; Qin, Yan; Cheng, Zhihong; Chen, Daofeng

    2014-10-01

    The mass spectrometric (MS) analysis of flavone di-C-glycosides has been a difficult task due to pure standards being unavailable commercially and to that the reported relative intensities of some diagnostic ions varied with MS instruments. In this study, five flavone di-C-glycoside standards from Viola yedoensis have been systematically studied by high performance liquid chromatography-electrospray ionization-tandem ion trap mass spectrometry (HPLC-ESI-IT-MS(n)) in the negative ion mode to analyze their fragmentation patterns. A new MS(2) and MS(3) hierarchical fragmentation for the identification of the sugar nature (hexoses or pentoses) at C-6 and C-8 is presented based on previously established rules of fragmentation. Here, for the first time, we report that the MS(2) and MS(3) structure-diagnostic fragments about the glycosylation types and positions are highly dependent on the configuration of the sugars at C-6 and C-8. The base peak ((0,2) X1 (0,2) X(2)(-) ion) in MS(3) spectra of di-C-glycosides could be used as a diagnostic ion for flavone aglycones. These newly proposed fragmentation behaviors have been successfully applied to the characterization of flavone di-C-glycosides found in V. yedoensis. A total of 35 flavonoid glycosides, including 1 flavone mono-C-hexoside, 2 flavone 6,8-di-C-hexosides, 11 flavone 6,8-di-C-pentosides, 13 flavone 6,8-C-hexosyl-C-pentosides, 5 acetylated flavone C-glycosides and 3 flavonol O-glycosides, were identified or tentatively identified on the base of their UV profiles, MS and MS(n) (n = 5) data, or by comparing with reference substances. Among these, the acetylated flavone C-glycosides were reported from V. yedoensis for the first time.

  9. Separation and analysis of phenolic acids from Salvia miltiorrhiza and its related preparations by off-line two-dimensional hydrophilic interaction chromatography×reversed-phase liquid chromatography coupled with ion trap time-of-flight mass spectrometry.

    Science.gov (United States)

    Sun, Wanyang; Tong, Ling; Miao, Jingzhuo; Huang, Jingyi; Li, Dongxiang; Li, Yunfei; Xiao, Hongting; Sun, Henry; Bi, Kaishun

    2016-01-29

    Salvia miltiorrhiza (SM) is one of the most widely used Traditional Chinese Medicine. Active constituents of SM mainly contain hydrophilic phenolic acids (PAs) and lipophilic tanshinones. However, due to the existing of multiple ester bonds and unsaturated bonds in the structures, PAs have numerous chemical conversion products. Many of them are so low-abundant that hard to be separated using conventional methods. In this study, an off-line two-dimensional liquid chromatography (2D-LC) method was developed to separate PAs in SM and its related preparations. In the first dimension, samples were fractionated by hydrophilic interaction chromatography (HILIC) (Acchrom×Amide, 4.6×250mm, 5μm) mainly based on the hydrogen bonding effects. The fractions were then separated on reversed-phase liquid chromatography (RP-LC) (Acquity HSS T3, 2.1×50mm, 1.7μm) according to hydrophobicity. For the selective identification of PAs, diode array detector (DAD) and electrospray ionization tandem ion trap time-of-flight mass spectrometry (ESI-IT-TOF-MS) were employed. Practical and effective peak capacities of all the samples were greater than 2046 and 1130, respectively, with the orthogonalities ranged from 69.7% to 92.8%, which indicated the high efficiency and versatility of this method. By utilizing the data post-processing techniques, including mass defect filter, neutral loss filter and product ion filter, a total of 265 compounds comprising 196 potentially new PAs were tentatively characterized. Twelve kinds of derivatives, mainly including glycosylated compounds, O-alkylated compounds, condensed compounds and hydrolyzed compounds, constituted the novelty of the newly identified PAs. The HILIC×RP-LC/TOF-MS system expanded our understanding on PAs of S. miltiorrhiza and its related preparations, which could also benefit the separation and characterization of polar constituents in complicated herbal extracts.

  10. Charged nanodiamonds in a Paul trap

    Science.gov (United States)

    Streed, Erik

    2015-05-01

    Colloidal nanodiamonds were ionized with atmospheric electrospray and loaded into a Paul trap. Fluorescence from atom-like NV0 and NV- colour centres has been observed. The very low intrinsic absorption of bulk diamond is favourable for reducing the heating of cooled, trapped, nanodiamond ions from the surrounding blackbody radiation of the trapping apparatus. The isolated environment of the ion trap is also favourable for in-situ modification of nanodiamond to reduce absorption inducing defects through either physical or chemical processes. The presence or intentional introduction of high luminescence atom-like colour centre defects such as NV or SiV offer the prospect of direct laser cooling in nanodiamonds with low emissivity. Such laser cooled nano-ions are of interest for sympathetically cooling ions of similar charge/mass ratios that lack closed optical transitions, such as large biomolecules. ARC Future Fellow.

  11. Determination of 26 Kinds of Volatile Organic Compounds in Water with Purge and Trap/Gas Chromatography-Mass Spectrometry%吹扫捕集/GC-MS法测定水中26种挥发性有机物

    Institute of Scientific and Technical Information of China (English)

    张芹; 曾凡海; 王少青

    2013-01-01

    采用吹扫捕集/气相色谱-质谱(GC-MS)法测定水中26种挥发性有机物(VOCs),并对吹扫捕集条件进行优化,分析了吹扫温度和吹扫时间、解吸温度和解吸时间对吹扫捕集效率的影响.分析结果表明,在此条件下,挥发性有机物的线性相关系数为0.999 0~0.999 9,平均加标回收率为94.0%~108.3%,相对标准偏差为2.4%~6.1%,具有较好的线性关系,准确度和精密度;方法检出限为0.03~0.28 μg/L,远低于《地表水环境质量标准》(GB 3838-2002)中限值.%Purge and trap/gas chromatography-mass spectrometry was used to determine 26 volatile organic compounds (VOCs) in water, and the conditions of the method were optimized. The influences of purge temperature, purge time, desorption temperature and desorption time on the efficiency of purge and trap were analyzed. Under the optimized conditions, this method had good linear relations, accuracy and precision, with a linear correlation coefficient of VOCs of 0. 999 0~0. 999 9, an average recovery of 94. 0%~ 108. 3% , a relative standard deviation of 2. 4%~6. 1% and a detection limit of 0. 03~0. 28 μg/L, which is much lower than the mid-limited value stipulated in Environmental Quality Standards for Surface Water (GB 3838-2002).

  12. Identification of Metabolites of 6′-Hydroxy-3,4,5,2′,4′-pentamethoxychalcone in Rats by a Combination of Ultra-High-Performance Liquid Chromatography with Linear Ion Trap-Orbitrap Mass Spectrometry Based on Multiple Data Processing Techniques

    Directory of Open Access Journals (Sweden)

    Siyi Liu

    2016-09-01

    Full Text Available In this study, an efficient strategy was established using ultra-high-performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometry (UHPLC-LTQ-Orbitrap MS to profile the in vivo metabolic fate of 6′-hydroxy-3,4,5,2′,4′-pentamethoxychalcone (PTC in rat urine and feces. The UHPLC-LTQ-Orbitrap method combines the high trapping capacity and MSn scanning function of the linear ion trap along with accurate mass measurements within 5 ppm and a resolving power of up to 30,000 over a wider dynamic range compared to many other mass spectrometers. In order to reduce the potential interferences of endogenous substances, the post-acquisition processing method including high-resolution extracted ion chromatogram (HREIC and multiple mass defect filters (MMDF were developed for metabolite detection. As a result, a total of 60 and 35 metabolites were detected in the urine and feces, respectively. The corresponding in vivo reactions such as methylation, hydroxylation, hydrogenation, decarbonylation, demethylation, dehydration, methylation, demethoxylation, sulfate conjugation, glucuronide conjugation, and their composite reactions were all detected in this study. The result on PTC metabolites significantly expanded the understanding of its pharmacological effects, and could be targets for future studies on the important chemical constituents from herbal medicines.

  13. Mass measurement of radioactive isotopes

    CERN Document Server

    Kluge, H J; Scheidenberger, C

    2004-01-01

    The highest precision in mass measurements on short-lived radionuclides is obtained using trapping and cooling techniques. Here, the experimental storage ring (ESR) at GSI/Darmstadt and the tandem Penning trap mass spectrometer ISOLTRAP at ISOLDE/CERN play an important role. Status and recent results on mass measurements of radioactive nuclides with ESR and ISOLTRAP are summarized.

  14. 1985-86 Trapping Proposal

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Annual Trapping Plan for the 1985-1986 trapping season at Clarence Cannon NWR outlines rules and regulations for the trapping of beaver and muskrat on the...

  15. Application of a hybrid ordered mesoporous silica as sorbent for solid-phase multi-residue extraction of veterinary drugs in meat by ultra-high-performance liquid chromatography coupled to ion-trap tandem mass spectrometry.

    Science.gov (United States)

    Casado, Natalia; Morante-Zarcero, Sonia; Pérez-Quintanilla, Damián; Sierra, Isabel

    2016-08-12

    A quick, sensitive and selective analytical reversed-phase multi-residue method using ultra-high performance liquid chromatography coupled to an ion-trap mass spectrometry detector (UHPLC-IT-MS/MS) operating in both positive and negative ion mode was developed for the simultaneous determination of 23 veterinary drug residues (β-blockers, β-agonists and Non-Steroidal Anti-inflammatory Drugs (NSAIDs)) in meat samples. The sample treatment involved a liquid-solid extraction followed by a solid-phase extraction (SPE) procedure. SBA-15 type mesoporous silica was synthetized and modified with octadecylsilane, and the resulting hybrid material (denoted as SBA-15-C18) was applied and evaluated as SPE sorbent in the purification of samples. The materials were comprehensively characterized, and they showed a high surface area, high pore volume and a homogeneous distribution of the pores. Chromatographic conditions and extraction procedure were optimized, and the method was validated according to the Commission Decision 2002/657/EC. The method detection limits (MDLs) and the method quantification limits (MQLs) were determined for all the analytes in meat samples and found to range between 0.01-18.75μg/kg and 0.02-62.50μg/kg, respectively. Recoveries for 15 of the target analytes ranged from 71 to 98%. In addition, for comparative purpose SBA-15-C18 was evaluated towards commercial C18 amorphous silica. Results revealed that SBA-15-C18 was clearly more successful in the multi-residue extraction of the 23 mentioned analytes with higher recovery values. The method was successfully tested to analyze prepacked preparations of mince bovine meat. Traces of propranolol, ketoprofen and diclofenac were detected in some samples.

  16. Simultaneous determination of methyl tert.-butyl ether and its degradation products, other gasoline oxygenates and benzene, toluene, ethylbenzene and xylenes in Catalonian groundwater by purge-and-trap-gas chromatography-mass spectrometry.

    Science.gov (United States)

    Rosell, Mònica; Lacorte, Sílvia; Ginebreda, Antoni; Barceló, Damià

    2003-05-02

    In Catalonia (northeast Spain), a monitoring program was carried out to determine methyl tert.-butyl ether (MTBE), its main degradation products, tert.-butyl alcohol (TBA), tert.-butyl formate (TBF), and other gasoline additives, the oxygenate dialkyl ethers ethyl tert.-butyl ether, tert.-amyl methyl ether and diisopropyl ether and the aromatic compounds benzene, toluene, ethylbenzene and xylene (BTEX) in 21 groundwater wells that were located near different gasoline point sources (a gasoline spill and underground storage tank leakage). Purge-and-trap coupled to gas chromatography-mass spectrometry was optimised for the simultaneous determination of the above mentioned compounds and enabled to detect concentrations at ng/l or sub-microg/l concentrations. Special attention was given to the determination of polar MTBE degradation products, TBA and TBF, since not much data on method performance and environmental levels are given on these compounds in groundwater. All samples analysed contained MTBE at levels between 0.3 and 70 microg/l. Seven contaminated hot spots were identified with levels up to US Environmental Protection Agency drinking water advisory (20-40 microg/l) and a maximum concentration of 670 microg/l (doubling the Danish suggested toxicity level of 350 microg/l). Samples with high levels of MTBE contained 0.1-60 microg/l of TBA, indicating (but not proving) in situ degradation of parent compound. In all cases, BTEX was at low concentrations or not detected showing less solubility and persistence than MTBE. This fact confirms the suitability of MTBE as a tracer or indicator of long-term gasoline contamination than the historically used BTEX.

  17. Real-time air monitoring of mustard gas and Lewisite 1 by detecting their in-line reaction products by atmospheric pressure chemical ionization ion trap tandem mass spectrometry with counterflow ion introduction.

    Science.gov (United States)

    Okumura, Akihiko; Takada, Yasuaki; Watanabe, Susumu; Hashimoto, Hiroaki; Ezawa, Naoya; Seto, Yasuo; Sekiguchi, Hiroshi; Maruko, Hisashi; Takayama, Yasuo; Sekioka, Ryoji; Yamaguchi, Shintaro; Kishi, Shintaro; Satoh, Takafumi; Kondo, Tomohide; Nagashima, Hisayuki; Nagoya, Tomoki

    2015-01-20

    A new method enabling sensitive real-time air monitoring of highly reactive chemical warfare agents, namely, mustard gas (HD) and Lewisite 1 (L1), by detecting ions of their in-line reaction products instead of intact agents, is proposed. The method is based on corona discharge-initiated atmospheric pressure chemical ionization coupled with ion trap tandem mass spectrometry (MS(n)) via counterflow ion introduction. Therefore, it allows for highly sensitive and specific real-time detection of a broad range of airborne compounds. In-line chemical reactions, ionization reactions, and ion fragmentations of these agents were investigated. Mustard gas is oxygenated in small quantity by reactive oxygen species generated in the corona discharge. With increasing air humidity, the MS(2) signal intensity of protonated molecules of mono-oxygenated HD decreases but exceeds that of dominantly existing intact HD. This result can be explained in view of proton affinity. Lewisite 1 is hydrolyzed and oxidized. As the humidity increases from zero, the signal of the final product, namely, didechlorinated, dihydroxylated, and mono-oxygenated L1, quickly increases and reaches a plateau, giving the highest MS(2) and MS(3) signals among those of L1 and its reaction products. The addition of minimal moisture gives the highest signal intensity, even under low humidity. The method was demonstrated to provide sufficient analytical performance to meet the requirements concerning hygienic management and counter-terrorism. It will be the first practical method, in view of sensitivity and specificity, for real-time air monitoring of HD and L1 without sample pretreatment.

  18. Comparison of two ionic liquid dispersive liquid-liquid microextraction approaches for the determination of benzoylurea insecticides in wastewater using liquid chromatography-quadrupole-linear ion trap-mass spectrometry: evaluation of green parameters.

    Science.gov (United States)

    Vázquez, M M Parrilla; Vázquez, P Parrilla; Galera, M Martínez; Moreno, A Uclés

    2014-08-22

    Two dispersive liquid-liquid microextraction (DLLME) approaches including temperature-controlled ionic liquid dispersive liquid-liquid microextraction (TCIL-DLLME) and ultrasound-assisted ionic liquid dispersive liquid-liquid microextraction (US-IL-DLLME) were compared for the extraction of six benzoylurea insecticides (diflubenzuron, triflumuron, hexaflumuron, teflubenzuron, lufenuron and flufenoxuron) from wastewater samples prior to their determination by high-performance liquid chromatography with a hybrid triple quadrupole-linear ion trap-mass spectrometer (LC-QqLIT-MS/MS). Influential parameters affecting extraction efficiency were systematically studied and optimized and the most significant green parameters were quantified and compared. The best results were obtained using the US-IL-DLLME procedure, which employed the IL 1-octyl-3-methylimidazolium hexafluorophosphate ([C8MIM][PF6]) and methanol (MeOH) as extraction and disperser solvent, respectively. US-IL-DLLME procedure was fast, easy, low environmental toxicity and, it was also able to successfully extract all selected benzoylureas. This method was extensively validated with satisfactory results: limits of detection and quantification were in the range 0.5-1.0 ng L(-1) and 1.5-3.5 ng L(-1), respectively, whereas recovery rates ranged from 89 to 103% and the relative standard deviations were lower than 13.4%. The applicability of the method was assessed with the analysis of effluent wastewater samples from a wastewater treatment plant located in an agricultural zone of Almería (Spain) and the results indicated the presence of teflubenzuron at mean concentration levels of 11.3 ng L(-1). US-IL-DLLME sample treatment in combination with LC-QqLIT-MS/MS has demonstrated to be a sensitive, selective and efficient method to determine benzoylurea insecticides in wastewaters at ultra-trace levels.

  19. Use of liquid chromatography coupled to low- and high-resolution linear ion trap mass spectrometry for studying the metabolism of paynantheine, an alkaloid of the herbal drug Kratom in rat and human urine.

    Science.gov (United States)

    Philipp, Anika A; Wissenbach, Dirk K; Weber, Armin A; Zapp, Josef; Zoerntlein, Siegfried W; Kanogsunthornrat, Jidapha; Maurer, Hans H

    2010-04-01

    The Thai medicinal plant Mitragyna speciosa (Kratom in Thai) is misused as a herbal drug of abuse. During studies on the main Kratom alkaloid mitragynine (MG) in rats and humans, several dehydro analogs could be detected in urine of Kratom users, which were not found in rat urine after administration of pure MG. Questions arose as to whether these compounds are formed from MG only by humans or whether they are metabolites formed from the second abundant Kratom alkaloid paynantheine (PAY), the dehydro analog of MG. Therefore, the aim of the presented study was to identify the phase I and II metabolites of PAY in rat urine after administration of the pure alkaloid. This was first isolated from Kratom leaves. Liquid chromatography-linear ion trap mass spectrometry provided detailed structure information of the metabolites in the MS(n) mode particularly with high resolution. Besides PAY, the following phase I metabolites could be identified: 9-O-demethyl PAY, 16-carboxy PAY, 9-O-demethyl-16-carboxy PAY, 17-O-demethyl PAY, 17-O-demethyl-16,17-dihydro PAY, 9,17-O-bisdemethyl PAY, 9,17-O-bisdemethyl-16,17-dihydro PAY, 17-carboxy-16,17-dihydro PAY, and 9-O-demethyl-17-carboxy-16,17-dihydro PAY. These metabolites indicated that PAY was metabolized via the same pathways as MG. Several metabolites were excreted as glucuronides or sulfates. The metabolism studies in rats showed that PAY and its metabolites corresponded to the MG-related dehydro compounds detected in urine of the Kratom users. In conclusion, PAY and its metabolites may be further markers for a Kratom abuse in addition of MG and its metabolites.

  20. Simultaneous qualitative and quantitative determination of phenolic compounds in Aloe barbadensis Mill by liquid chromatography-mass spectrometry-ion trap-time-of-flight and high performance liquid chromatography-diode array detector.

    Science.gov (United States)

    Wu, Xiaofang; Ding, Wenjing; Zhong, Jiasheng; Wan, Jinzhi; Xie, Zhiyong

    2013-06-01

    An effective and comprehensive method was developed for the simultaneous analysis of phenolic compounds in the dried exudate of Aloe barbadensis Mill by liquid chromatography-mass spectrometry-ion trap-time-of-flight (LCMS-IT-TOF) and high performance liquid chromatography-diode array detector (HPLC-DAD). Qualitative analysis of all the compounds presented in A. barbadensis Mill was performed on LCMS-IT-TOF, and the diagnostic fragmentation patterns of different types of phenolic compounds (chromones, phenyl pyrones, naphthalene derivative, anthrones and anthraquinones) were discussed on the basis of ESI-IT-TOF MS of components in A. barbadensis Mill and eleven authentic standards. Under the optimal HPLC-DAD chromatographic conditions, quantification of 11 typical phenolic compounds in 15 batches of A. barbadensis Mill was achieved on an Agilent TC-C18 column using gradient elution with a solvent system of methanol and water at a flow rate of 1.0mLmin(-1) and detected at 230nm. All calibration curves exhibited good linear relationship (r(2)>0.9991). The relative standard deviation values for intraday precision were less than 2% with accuracies between 98.21% and 104.57%. The recoveries of the eleven analytes ranged from 97.53 to 105.00% with RSDs less than 2%. This is the first simultaneous characterization and quantitative determination of multiple phenolic compounds in A. barbadensis Mill from locally grown cultivars in China by LCMS-IT-TOF and HPLC-DAD, which can be applied to standardize the quality of A. barbadensis Mill and the future design of nutraceutical and cosmetic preparations.

  1. Sampling of organophosphorus pesticides at trace levels in the atmosphere using XAD-2 adsorbent and analysis by gas chromatography coupled with nitrogen-phosphorus and ion-trap mass spectrometry detectors.

    Science.gov (United States)

    Russo, Mario Vincenzo; Avino, Pasquale; Cinelli, Giuseppe; Notardonato, Ivan

    2012-09-01

    This paper shows an analytical methodology based on solid-phase extraction by XAD-2 adsorbent and gas chromatography (GC) coupled with nitrogen-phosphorus (NPD) and ion-trap mass spectrometry detectors (ITMS) in negative chemical ionization (NCI) mode analyses for investigating organophosphorus pesticides (OPs) at trace levels (in nanograms per cubic meter) in the atmosphere: in particular, we set up a procedure for analyzing 38 OPs. For the analytical methodology linearity responses have been obtained in GC-NPD (r > 0.9982) and GC-NCI/ITMS (r > 0.9974) in a large linearity range (0.10-500 pg μL(-1) in both cases) whereas the limits of detection range between 0.01 and 0.03 pg μL(-1) in both the techniques with a relative standard deviation (RSD) below 9.0 in both cases. Particular attention has been devoted to investigate the effect of different solvents (n-hexane, benzene, chloroform, carbon disulfide, acetonitrile) on the OP recovery as well the breakthrough volumes have been evaluated (100% recovery up to 4,286 L g(-1)). The study has also investigated the OP recoveries at different sampling flow rates (1.5 and 2.0 L min(-1)) for determining the optimal conditions for sample collection. Finally, the whole approach has been successfully applied to real samples collected in four different areas in the Molise region (Central Italy) during different seasons: the results show that parathion-ethyl, dimethoate, omethoate, and malathion are present in all periods at low levels (ranging between 70 and 10 ng m(-3)): their levels in such periods can be correlated with spraying as well atmospheric conditions favoring the dispersion/accumulation of these pollutants.

  2. Naturally occurring glucosinolates in plant extracts of rocket salad (Eruca sativa L.) identified by liquid chromatography coupled with negative ion electrospray ionization and quadrupole ion-trap mass spectrometry.

    Science.gov (United States)

    Cataldi, Tommaso R I; Rubino, Alessandra; Lelario, Filomena; Bufo, Sabino A

    2007-01-01

    A method for the comprehensive profiling of intact glucosinolates (GLSs), major and minor, occurring in leaves and seeds of rocket salad (Eruca sativa L.) is presented using optimized reversed-phase liquid chromatography (RP-LC) with electrospray ionization (ESI) ion trap mass spectrometry (ITMS). ESI-ITMS in the negative mode was confirmed to be very suitable to analyze these compounds in crude extracts. After extraction from the plant material with methanol/water (70:30 v/v) at 70 degrees C, the analytes of interest were separated on a C18 column using an eluent acidified with formic acid (0.1%) and modified with acetonitrile. All the GLSs found in leaves of rocket salad gave good signals corresponding to the deprotonated precursor ion, [M-H]-. Although the mass spectra also exhibited an analytically important non-covalent adduct ion at [2M-H]-, the structures of glucosinolates were confirmed by extensive sequential MS analysis, thereby substantially improving the identification of unknown compounds. The results obtained not only revealed in leaves of E. sativa at least twelve species of GLSs including seven aliphatic compounds (glucoraphanin with [M-H]- at m/z ratio of 436, glucoerucin at m/z 420, 4-mercaptobutyl-GLS at m/z 406, progoitrin/epiprogoitrin at m/z 388, sinigrin at m/z 358, 4-methylpentyl- and n-hexyl-GLS at m/z 402) and three indole glucosinolates (i.e., three N-heterocyclic compounds: 4-hydroxyglucobrassicin and 5-hydroxyglucobrassicin at m/z 463, and 4-methoxy-glucobrassicin at m/z 477), but also two structurally related compounds containing one intermolecular disulfide linkage (4-(beta-D-glucopyranosyldisulfanyl)butyl-GLS at m/z 600 and a dimeric 4-mercaptobutyl-GLS at m/z 811). This latter symmetric disulfide was previously considered as an artefact formed during extraction of GLSs from vegetative tissues. Glucosinolates were detected in the leaves with a wide range of contents (10-200 micromol/g) and a great variation in the composition. Only

  3. Search For Trapped Antihydrogen

    CERN Document Server

    Andresen, Gorm B; Baquero-Ruiz, Marcelo; Bertsche, William; Bowe, Paul D; Bray, Crystal C; Butler, Eoin; Cesar, Claudio L; Chapman, Steven; Charlton, Michael; Fajans, Joel; Friesen, Tim; Fujiwara, Makoto C; Gill, David R; Hangst, Jeffrey S; Hardy, Walter N; Hayano, Ryugo S; Hayden, Michael E; Humphries, Andrew J; Hydomako, Richard; Jonsell, Svante; Jørgensen, Lars V; Kurchaninov, Lenoid; Lambo, Ricardo; Madsen, Niels; Menary, Scott; Nolan, Paul; Olchanski, Konstantin; Olin, Art; Povilus, Alexander; Pusa, Petteri; Robicheaux, Francis; Sarid, Eli; Nasr, Sarah Seif El; Silveira, Daniel M; So, Chukman; Storey, James W; Thompson, Robert I; van der Werf, Dirk P; Wilding, Dean; Wurtele, Jonathan S; Yamazaki, Yasunori

    2011-01-01

    We present the results of an experiment to search for trapped antihydrogen atoms with the ALPHA antihydrogen trap at the CERN Antiproton Decelerator. Sensitive diagnostics of the temperatures, sizes, and densities of the trapped antiproton and positron plasmas have been developed, which in turn permitted development of techniques to precisely and reproducibly control the initial experimental parameters. The use of a position-sensitive annihilation vertex detector, together with the capability of controllably quenching the superconducting magnetic minimum trap, enabled us to carry out a high-sensitivity and low-background search for trapped synthesised antihydrogen atoms. We aim to identify the annihilations of antihydrogen atoms held for at least 130 ms in the trap before being released over ~30 ms. After a three-week experimental run in 2009 involving mixing of 10^7 antiprotons with 1.3 10^9 positrons to produce 6 10^5 antihydrogen atoms, we have identified six antiproton annihilation events that are consist...

  4. Development of a Kingdon ion trap system for trapping externally injected highly charged ions.

    Science.gov (United States)

    Numadate, Naoki; Okada, Kunihiro; Nakamura, Nobuyuki; Tanuma, Hajime

    2014-10-01

    We have developed a Kingdon ion trap system for the purpose of the laboratory observation of the x-ray forbidden transitions of highly charged ions (HCIs). Externally injected Ar(q+) (q = 5-7) with kinetic energies of 6q keV were successfully trapped in the ion trap. The energy distribution of trapped ions is discussed in detail on the basis of numerical simulations. The combination of the Kingdon ion trap and the time-of-flight mass spectrometer enabled us to measure precise trapping lifetimes of HCIs. As a performance test of the instrument, we measured trapping lifetimes of Ar(q+) (q = 5-7) under a constant number density of H2 and determined the charge-transfer cross sections of Ar(q+)(q = 5, 6)-H2 collision systems at binary collision energies of a few eV. It was confirmed that the present cross section data are consistent with previous data and the values estimated by some scaling formula.

  5. Trapped charged particles a graduate textbook with problems and solutions

    CERN Document Server

    Madsen, Niels; Thompson, Richard C

    2016-01-01

    At Les Houches in January 2015, experts in the field of particle trapping came together to discuss the fundamental physics of traps and the different types of applications. This textbook collates the lectures delivered there; the Second Winter School on Physics with Trapped Charged Particles. Taken as a whole, the book gives an overview of why traps for charged particles are important, how they work, their special features and limitations, and their application in areas such as precision measurements, mass spectrometry, optical clocks, plasma physics, antihydrogen creation, quantum simulation and quantum information processing. Chapters from various world experts include those on the basic properties of Penning traps, RF traps and particle accelerators, as well as those covering important practical aspects such as vacuum systems, detection techniques, and different types of particle cooling including laser cooling. Finally, individual chapters deal with the different areas of application listed above. Each ...

  6. Ion traps in nuclear physics-Recent results and achievements

    Science.gov (United States)

    Eronen, Tommi; Kankainen, Anu; Äystö, Juha

    2016-11-01

    Ion traps offer a way to determine nuclear binding energies through atomic mass measurements with a high accuracy and they are routinely used to provide isotopically or even isomerically pure beams of short-living ions for post-trap decay spectroscopy experiments. In this review, different ion-trapping techniques and progresses in recent nuclear physics experiments employing low-energy ion traps are discussed. The main focus in this review is on the benefit of recent high accuracy mass measurements to solve some key problems in physics related to nuclear structure, nuclear astrophysics as well as neutrinos. Also, several cases of decay spectroscopy experiments utilizing trap-purified ion samples are summarized.

  7. Online eluent-switching technique coupled anion-exchange liquid chromatography–ion trap tandem mass spectrometry for analysis of non-steroidal anti-inflammatory drugs in pig serum.

    Science.gov (United States)

    Chang, Kai Chun; Lin, Jyh Shiun; Cheng, Cheanyeh

    2015-11-27

    A novel method for online extraction, pH-gradient separation, and analysis of nine non-steroidal anti-inflammatory drugs (NSAIDs) was developed by coupling online eluent-switching technique to single anion-exchange chromatographic column/ion trap mass spectrometer (MS) and used for monitoring NSAIDs residues in pig serum. A neutral eluent and a pH-gradient eluent were used for extraction and separation of NSAIDs, respectively. Each of nine NSAIDs has an MS precursor ion of either [M−H]− or [M−Na]−. The extracted ion chromatogram for a specific product ion of each NSAID was used for its quantitative analysis. The dynamic linear ranges of calibration curves were all 0–200 ng mL−1 (R2 > 0.9950). The analysis accuracies estimated by spiking standard concentrations at 20, 100, and 200 ng mL−1 were 80.5–99.9%. The corresponding intra-day and inter-day precisions (RSD%) were 2.5–14.5% and 2.9–15.2%, respectively. The limit of detection/limit of quantitation of NSAIDs were 1.3/4.3, 0.5/1.6, 0.2/0.5, 2.5/8.2, 1.5/4.9, 0.6/2.1, 0.6/2.0, 0.5/1.7, and 0.6/2.1 ng mL−1 for carprofen, diclofenac, flunixin, ibuprofen, ketoprofen, meclofenamic acid sodium, mefenamic acid, niflumic acid, and tolfenamic acid, respectively. After 1 h injection of a dose containing 2 mg kg−1 weight pig of flunixin and tolfenamic acid to the pigs, a residue amount of 3480 ± 36 ng mL−1 and 431 ± 13 ng mL−1, respectively, was reached for the incurred pig serum specimens and both residues were reduced to about 20 ng mL−1 at the time of 24 h.

  8. Peakfitter — an integrated Excel-based Visual Basic program for processing multiple skewed and shifting Gaussian-like spectral peaks simultaneously: application to radio frequency glow discharge ion trap mass spectrometry

    Science.gov (United States)

    Eanes, Ritchie C.; Marcus, R. Kenneth

    2000-04-01

    This article is an electronic publication in Spectrochimica Acta Electronica (SAE), a section of Spectrochimica Acta Part B (SAB). The hardcopy text is accompanied by an electronic archive, stored on the SAE homepage at (http://www.elsevier.nl/locate/sabe). The archive contains program and data files. The main article discusses the scientific spectroscopic and instrumental aspects of the subject and explains the purpose of the program and data files. The work deals with a Microsoft Excel Visual Basic program, Peakfitter, which can process multiple Gaussian-shaped spectral peaks quickly and easily. The program employs Microsoft Excel Solver to process any Gaussian-like spectra that can be opened in Microsoft Excel 97. Up to three peaks in one to 225 spectra, each containing up to 2000 data points can be processed per data file to give background corrected peak areas for both raw data and its associated fit data as calculated by the trapezoidal method or by simple successive addition of channel intensities across each peak. Concurrently output also includes fit peak heights for Gaussian-shaped spectral peaks. Use of other statistical distributions such as the Lorentzian model requires only slight modification to a template file. Hence, Peakfitter was actually written as two application programs, 'Gaussfitter' and 'Lorenfitter' to accommodate spectra of Gaussian or Lorentzian character, respectively. Written initially to process data from a radio frequency glow discharge ion trap mass spectrometer (rf-GD/ITMS), the program is useful for processing sequentially acquired spectra, which have a limited number of data points across each peak. The user may examine and manipulate program variables in cases where the raw data is skewed with respect to the fit data. An assessment of Peakfitter is given using rf-GD/ITMS elemental analysis and ion-molecule reaction data. Peakfitter's (i.e. 'Gaussfitter's) utility in processing rf-GD/ITMS spectra is characterized by a slight

  9. Simultaneous determination of 19 triazine pesticides and degradation products in processed cereal samples from Chinese total diet study by isotope dilution–high performance liquid chromatography–linear ion trap mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Li, Peng [College of Veterinary Medicine, China Agricultural University, Beijing 100193 (China); China National Center for Food Safety Risk Assessment, Beijing 100021 (China); Yang, Xin, E-mail: beijing-yangxin@163.com [China National Center for Food Safety Risk Assessment, Beijing 100021 (China); Miao, Hong; Zhao, Yunfeng [China National Center for Food Safety Risk Assessment, Beijing 100021 (China); Key Lab of Food Safety Risk Assessment, Ministry of Health, Beijing 100021 (China); Liu, Wei [Shandong Province Environmental Monitoring Centre, Jinan 250013 (China); Wu, Yongning, E-mail: china_cdc@yahoo.cn [College of Veterinary Medicine, China Agricultural University, Beijing 100193 (China); China National Center for Food Safety Risk Assessment, Beijing 100021 (China); Key Lab of Food Safety Risk Assessment, Ministry of Health, Beijing 100021 (China)

    2013-06-05

    Graphical abstract: -- Highlights: •19 triazines were determined in cereal samples from Chinese TDS for the first time. •Isotope dilution technique and HPLC–LIT-MS{sup 3} method are both applied in this study. •CCαs and CCβs are much lower in this work than those of the previous publications. -- Abstract: A selective and sensitive isotope dilution–high performance liquid chromatography–linear ion trap mass spectrometry (Isotope Dilution–HPLC–LIT-MS{sup 3}) method was developed for the simultaneous determination of 19 triazine pesticides and their degradation products in processed cereal samples from Chinese total diet study (TDS). The method integrated the addition of isotope internal standards, liquid–liquid extraction (LLE), clean-up with MCX solid-phase extraction (SPE) cartridges and HPLC–LIT-MS{sup 3} analysis with selected reaction monitoring (SRM) mode. Matrix-matched calibration curves showed good linearity (R{sup 2} ≥ 0.9940) verified by applying the Mandel's fitting test (p > 0.087) performed at the 95% confidence level. Decision limits (CCαs) and detection capabilities (CCβs) of the 19 triazine pesticides and their degradation products fell in the ranges of 0.0020–0.4200 μg kg{sup −1} and 0.0024–0.4500 μg kg{sup −1}, respectively. Recoveries ranged from 70.1% to 112.8%, with the relative standard deviations (RSDs) ranging from 1.5% to 13.5%. Furthermore, the proposed method was applied to analyzing the proposed cereal samples from the fourth Chinese TDS. Eleven triazines were detected in six cereal samples with the concentrations ranging from 0.013 to 0.987 μg kg{sup −1}. This method can also be used for the further determination of the triazines in other food group composites, and ultimately served as a methodological foundation for assessing the triazines in the average Chinese diet in the general population.

  10. Axions and SN 1987A: Axion trapping

    Science.gov (United States)

    Burrows, Adam; Ressell, M. Ted; Turner, Michael S.

    1990-01-01

    If an axion of mass between about 10(exp -3) and 10 eV exists, axion emission would have significantly affected the cooling of the nascent neutron star associated with SN 1987A. For an axion of mass greater than about 10(exp -2) eV axions would, like neutrinos, have a mean-free path that is smaller than the size of a neutron star, and thus would become trapped and radiated from an axion sphere. The trapping regime is treated by using numerical models of the initial cooling of a hot neutron star that incorporate a diffusion approximation for axion-energy transport. The axion opacity due to inverse nucleon-nucleon, axion bremsstrahlung is computed; and then the numerical models are used to calculate the integrated axion luminosity, the temperature of the axion sphere, and the effect of axion emission on the neutrino bursts detected by the Kamiokande II (KII) and Irvine-Michigan-Brookhaven (IMB) water-Cherenkov detectors. The larger the axion mass, the stronger the trapping and the smaller the axion luminosity. The estimate of the axion mass is confirmed above which trapping is so strong that axion emission does not significantly affect the neutrino burst. Based upon the neutrino-burst duration - the most sensitive barometer of axion cooling - it is concluded that for an axion mass greater than about 3 eV axion emission would not have had a significant effect on the neutrino bursts detected by KII and IMB. It is strongly suggested that an axion with mass in the interval 10(exp -3) to 3 eV is excluded by the observation of neutrinos from SN 1987A.

  11. Ion funnel ion trap and process

    Science.gov (United States)

    Belov, Mikhail E [Richland, WA; Ibrahim, Yehia M [Richland, WA; Clowers, Biran H [West Richland, WA; Prior, David C [Hermiston, OR; Smith, Richard D [Richland, WA

    2011-02-15

    An ion funnel trap is described that includes a inlet portion, a trapping portion, and a outlet portion that couples, in normal operation, with an ion funnel. The ion trap operates efficiently at a pressure of .about.1 Torr and provides for: 1) removal of low mass-to-charge (m/z) ion species, 2) ion accumulation efficiency of up to 80%, 3) charge capacity of .about.10,000,000 elementary charges, 4) ion ejection time of 40 to 200 .mu.s, and 5) optimized variable ion accumulation times. Ion accumulation with low concentration peptide mixtures has shown an increase in analyte signal-to-noise ratios (SNR) of a factor of 30, and a greater than 10-fold improvement in SNR for multiply charged analytes.

  12. Trapping molecules on chips

    CERN Document Server

    Santambrogio, Gabriele

    2015-01-01

    In the last years, it was demonstrated that neutral molecules can be loaded on a microchip directly from a supersonic beam. The molecules are confined in microscopic traps that can be moved smoothly over the surface of the chip. Once the molecules are trapped, they can be decelerated to a standstill, for instance, or pumped into selected quantum states by laser light or microwaves. Molecules are detected on the chip by time-resolved spatial imaging, which allows for the study of the distribution in the phase space of the molecular ensemble.

  13. The Reusable Astronomy Portal (TRAP)

    Science.gov (United States)

    Donaldson, T.; Rogers, A.; Wallace, G.

    2012-09-01

    The Reusable Astronomy Portal (TRAP) aims to provide a common platform for rapidly deploying Astronomy Archives to the web. TRAP is currently under development for both the VAO Data Discovery Portal and the MAST Multi-Mission Portal (Figure 1). TRAP consists of 2 major software packages: the TRAP Client and the TRAP Server. The TRAP framework allows developers to deploy the Server, connect to data resources, then focus on building custom tools for the Client. TRAP is built upon proven industry technologies including the Ext/JS JavaScript Component Library, Mono.NET Web Services, and JSON message based APIs. The multi-layered architecture of TRAP decouples each layer: Client, Service and Data Access, enabling each to evolve independently over time. Although currently deployed to provide astronomy science data access, the TRAP architecture is flexible enough to thrive in any distributed data environment.

  14. Sodium hydride precipitation in sodium cold traps

    Energy Technology Data Exchange (ETDEWEB)

    McPheeters, C.C.; Raue, D.J.

    1980-06-01

    A series of experiments have been performed to test a calculational model for precipitation of NaH in sodium cold traps. The calculational model, called ACTMODEL, is a computer simulation that uses the system geometry and operating conditions as input to calculate a mass-transfer coefficient and the distribution of NaH in a cold trap. The ACTMODEL was tested using an analytical cold trap (ACT) that is simple and essentially one-dimensional. The ACT flow and temperature profile can be controlled at any desired condition. The ACT was analyzed destructively after each test to measure the actual NaH distribution. Excellent agreement was obtained between the ACTMODEL simulations and the experiments. Mass-transfer coefficients ranging upward from 6 x 10/sup -5/ m/s were measured in both packless and packed traps. As much as a fourfold increase in precipitation surface area was observed with increasing amount of NaH deposited. 11 figures, 2 tables.

  15. Ion bunch stacking in a Penning trap after purification in an electrostatic mirror trap

    CERN Document Server

    Rosenbusch, M; Blaum, K; Borgmann, Ch; Kreim, S; Lunney, D; Manea, V; Schweikhard, L; Wienholtz, F; Wolf, R N

    2014-01-01

    The success of many measurements in analytical mass spectrometry as well as in precision mass determinations for atomic and nuclear physics is handicapped when the ion sources deliver ``contaminations'', i.e., unwanted ions of masses similar to those of the ions of interest. In particular, in ion-trapping devices, large amounts of contaminant ions result in significant systematic errors-if the measurements are possible at all. We present a solution for such cases: The ions from a quasi-continuous source are bunched in a linear radio-frequency-quadrupole ion trap, separated by a multi-reflection time-of-flight section followed by a Bradbury-Nielsen gate, and then captured in a Penning trap. Buffer-gas cooling is used to damp the ion motion in the latter, which allows a repeated opening of the Penning trap for a stacking of mass-selected ion bunches. Proof-of-principle demonstrations have been performed with the ISOLTRAP setup at ISOLDE/CERN, both with Cs-133(+) ions from an off-line ion source and by applicati...

  16. Redesigning octopus traps

    Directory of Open Access Journals (Sweden)

    Eduarda Gomes

    2014-06-01

    In order to minimise the identified problems in the actual traps, the present work proposes a new design with the aim of reducing the volume and weight during transport, and also during onshore storage. Alternative materials to avoid corrosion and formation of encrustations were also proposed.

  17. Trapping of giant-planet cores - I. vortex aided trapping at the outer dead zone edge

    CERN Document Server

    Regaly, Zs; Csomos, P; Ataiee, S

    2013-01-01

    In this paper the migration of a 10 Earth mass planetary core is investigated at the outer boundary of the dead zone of a protoplanetary disc by means of 2D hydrodynamic simulations done with the GPU version of the FARGO code. In the dead zone the effective viscosity is greatly reduced due to the disc self-shielding against stellar UV radiation, X-rays from the stellar magnetosphere and interstellar cosmic rays. As a consequence, mass accumulation occurs near the outer dead zone edge, which is assumed to trap planetary cores enhancing the efficiency of the core accretion scenario to form giant planets. Contrary to the perfect trapping of planetary cores in 1D models, our 2D numerical simulations show that the trapping effect is greatly dependent on the width of the region where viscosity reduction is taking place. Planet trapping happens exclusively if the viscosity reduction is sharp enough to allow the development of large scale vortices due to the Rossby wave instability. The trapping is only temporarily, ...

  18. Ion trap system for radioactive ions at JYFL

    Energy Technology Data Exchange (ETDEWEB)

    Kolhinen, V.S.; Jokinen, A.; Rinta-Antila, S.; Szerypo, J. [University of Jyvaeskylae, Department of Physics (Finland); Aeystoe, J. [CERN, Geneva (Switzerland)

    2001-07-01

    The goal of the ion trap project in Jyvaeskylae is to improve the quality of radioactive beams at IGISOL (Ion Guide Isotope Separator On-Line), in terms of transverse emittance, energy spread and purity. This improvement is achieved with an aid of an RFQ cooler/buncher and a mass-selective cylindrical Penning trap (mass resolving power up to 10{sup 5}). Their final purpose is to produce cooled isobarically pure beams of exotic radioactivities mainly of exotic neutron-rich isotopes from fission (including refractory elements). In the Penning trap ions are confined in three dimensions in a superposition of static quadrupole electric and homogeneous magnetic fields. The magnetic field confines the ions in two dimensions in a plane perpendicular to the field direction. A confinement in the third, magnetic field direction (parallel to the trap axis) is done by a quadrupole electric field. The Penning trap system in Jyvaeskylae (JYFLTRAP) will contain two cylindrical Penning traps placed inside the same superconducting magnet (B=7 T). The first, purification trap, will accept cooled (continuous or bunched) beams from the RFQ cooler/buncher and perform the isobaric purification. The latter is - done using a combination of a buffer gas cooling and an azimuthal quadrupole RF-field providing mass- dependent centering of ions. This, in turn, allows mass-selective ejection of ions in short pulses. Clean monoisotopic bunched beams will be delivered for the nuclear spectroscopy studies, collinear laser spectroscopy experiments and precise nuclear mass measurements (10{sup -7} precision). The latter will be performed in the second, precision Penning trap (author)

  19. Characterizing optical dipole trap via fluorescence of trapped cesium atoms

    Institute of Scientific and Technical Information of China (English)

    LIU Tao; GENG Tao; YAN Shubin; LI Gang; ZHANG Jing; WANG Junmin; PENG Kunchi; ZHANG Tiancai

    2006-01-01

    Optical dipole trap (ODT) is becoming an important tool of manipulating neutral atoms. In this paper ODT is realized with a far-off resonant laser beam strongly focused in the magneto-optical trap (MOT) of cesium atoms. The light shift is measured by simply monitoring the fluorescence of the atoms in the magneto-optical trap and the optical dipole trap simultaneously. The advantages of our experimental scheme are discussed, and the effect of the beam waist and power on the potential of dipole trap as well as heating rate is analyzed.

  20. Detection of Trapped Antihydrogen

    CERN Document Server

    Hydomako, Richard Allan

    The ALPHA experiment is an international effort to produce, trap, and perform precision spectroscopic measurements on antihydrogen (the bound state of a positron and an antiproton). Based at the Antiproton Decelerator (AD) facility at CERN, the ALPHA experiment has recently magnetically confined antihydrogen atoms for the first time. A crucial element in the observation of trapped antihydrogen is ALPHA’s silicon vertexing detector. This detector contains sixty silicon modules arranged in three concentric layers, and is able to determine the three-dimensional location of the annihilation of an antihydrogen atom by reconstructing the trajectories of the produced annihilation products. This dissertation focuses mainly on the methods used to reconstruct the annihilation location. Specifically, the software algorithms used to identify and extrapolate charged particle tracks are presented along with the routines used to estimate the annihilation location from the convergence of the identified tracks. It is shown...

  1. Coherence in Microchip Traps

    CERN Document Server

    Treutlein, P; Steinmetz, T; Hänsch, T W; Reichel, J; Treutlein, Philipp; Hommelhoff, Peter; Steinmetz, Tilo; H\\"ansch, Theodor W.; Reichel, Jakob

    2003-01-01

    We report the coherent manipulation of internal states of neutral atoms in a magnetic microchip trap. Coherence lifetimes exceeding 1 s are observed with atoms at distances of $4-130 \\mu$m from the microchip surface. The coherence lifetime in the microtrap is independent of atom-surface distance and agrees well with the results of similar measurements in macroscopic magnetic traps. Due to the absence of surface-induced decoherence, a miniaturized atomic clock with a relative stability in the $10^{-13}$ range can be realized. For applications in quantum information processing, we propose to use microwave near-fields in the proximity of chip wires to create potentials that depend on the internal state of the atoms.

  2. Single Ion Trapping for the Enriched Xenon Observatory

    Energy Technology Data Exchange (ETDEWEB)

    Waldman, Samuel J.; /Stanford U., Phys. Dept. /SLAC

    2006-03-28

    In the last decade, a variety of neutrino oscillation experiments have established that there is a mass difference between neutrino flavors, without determining the absolute neutrino mass scale. The Enriched Xenon Observatory for neutrinoless double beta decay (EXO) will search for the rare decays of xenon to determine the absolute value of the neutrino mass. The experiment uses a novel technique to minimize backgrounds, identifying the decay daughter product in real time using single ion spectroscopy. Here, we describe single ion trapping and spectroscopy compatible with the EXO detector. We extend the technique of single ion trapping in ultrahigh vacuum to trapping in xenon gas. With this technique, EXO will achieve a neutrino mass sensitivity of {approx_equal} .010 eV.

  3. Ion Trap Quantum Computing

    Science.gov (United States)

    2011-12-01

    an inspiring speech at the MIT Physics of Computation 1st Conference in 1981, Feynman proposed the development of a computer that would obey the...on ion trap based 36 quantum computing for physics and computer science students would include lecture notes, slides, lesson plans, a syllabus...reading lists, videos, demonstrations, and laboratories. 37 LIST OF REFERENCES [1] R. P. Feynman , “Simulating physics with computers,” Int. J

  4. Water-Trapped Worlds

    CERN Document Server

    Menou, Kristen

    2013-01-01

    Although tidally-locked habitable planets orbiting nearby M-dwarf stars are among the best astronomical targets to search for extrasolar life, they may also be deficient in volatiles and water. Climate models for this class of planets show atmospheric transport of water from the dayside to the nightside, where it is precipitated as snow and trapped as ice. Since ice only slowly flows back to the dayside upon accumulation, the resulting hydrological cycle can trap a large amount of water in the form of nightside ice. Using ice sheet dynamical and thermodynamical constraints, I illustrate how planets with less than about a quarter the Earth's oceans could trap most of their surface water on the nightside. This would leave their dayside, where habitable conditions are met, potentially dry. The amount and distribution of residual liquid water on the dayside depend on a variety of geophysical factors, including the efficiency of rock weathering at regulating atmospheric CO2 as dayside ocean basins dry-up. Water-tr...

  5. Confining rigid balls by mimicking quadrupole ion trapping

    CERN Document Server

    Fan, Wenkai; Wang, Sihui; Zhou, Huijun

    2016-01-01

    The rotating saddle not only is an interesting system that is able to trap a ball near its saddle point, but can also intuitively illustrate the operating principles of quadrupole ion traps in modern physics. Unlike the conventional models based on the mass-point approximation, we study the stability of a ball in a rotating-saddle trap using rigid-body dynamics. The stabilization condition of the system is theoretically derived and subsequently verified by experiments. The results are compared with the previous mass-point model, giving large discrepancy as the curvature of the ball is comparable to that of the saddle. We also point out that the spin angular velocity of the ball is analogous to the cyclotron frequency of ions in an external magnetic field utilized in many prevailing ion-trapping schemes.

  6. Quantum computation with ``hot`` trapped ions

    Energy Technology Data Exchange (ETDEWEB)

    James, D.F.V. [Los Alamos National Lab., NM (United States); Schneider, S. [Los Alamos National Lab., NM (United States)]|[Univ. of Queensland, St. Lucia, Queensland (Australia); Milburn, G.J. [Univ. of Queensland, St. Lucia, Queensland (Australia)

    1998-12-31

    The authors describe two methods that have been proposed to circumvent the problem of heating by external electromagnetic fields in ion trap quantum computers. Firstly the higher order modes of ion oscillation (i.e., modes other than the center-of-mass mode) have much slower heating rates, and can therefore be employed as a reliable quantum information bus. Secondly they discuss a recently proposed method combining adiabatic passage and a number-state dependent phase shift which allows quantum gates to be performed using the center-of-mass mode as the information bus, regardless of its initial state.

  7. Atomic and nuclear physics with stored particles in ion traps

    CERN Document Server

    Kluge, H J; Herfurth, F; Quint, W

    2002-01-01

    Trapping and cooling techniques play an increasingly important role in many areas of science. This review concentrates on recent applications of ion traps installed at accelerator facilities to atomic and nuclear physics such as mass spectrometry of radioactive isotopes, weak interaction studies, symmetry tests, determination of fundamental constants, laser spectroscopy, and spectroscopy of highly-charged ions. In addition, ion traps are proven to be extremely efficient devices for (radioactive) ion beam manipulation as, for example, retardation, accumulation, cooling, beam cleaning, charge-breeding, and bunching.

  8. Lorentz-violating spinor electrodynamics and Penning traps

    CERN Document Server

    Ding, Yunhua

    2016-01-01

    The prospects are explored for testing Lorentz- and CPT-violating quantum electrodynamics in experiments with Penning traps. We present the Lagrange density of Lorentz-violating spinor electrodynamics with operators of mass dimensions up to six, and we discuss some of its properties. The theory is used to derive Lorentz- and CPT-violating perturbative shifts of the energy levels of a particle confined to a Penning trap. Observable signals are discussed for trapped electrons, positrons, protons, and antiprotons. Existing experimental measurements on anomaly frequencies are used to extract new or improved bounds on numerous coefficients for Lorentz and CPT violation, using sidereal variations of observables and comparisons between particles and antiparticles.

  9. Cylindrical Penning traps with dynamic orthogonalized anharmonicity compensation for precision experiments

    CERN Document Server

    Fei Xiang

    1999-01-01

    Harmonic potentials can be produced in cylindrical ion traps by means of dynamic orthogonalized anharmonicity compensation with use of two (or multiple) sets of compensation electrodes. One special example is for traps with multiple identical electrodes which are not only easy to construct and allow access to the center region of the trap for particle loading and releasing, laser beams, and microwaves, but also flexible in forming harmonic potential wells in many locations. The nested trap configuration and the side-by-side trap configuration are readily available in this special scheme. Analytical solutions for cylindrical traps with multiple sets of compensation potentials are presented. This work will be useful for studies involving Penning trap diagnostics, atomic and molecular interactions (including the production of antihydrogen atoms), accurate mass measurements of exotic particles, and precision measurements of the spin precession frequencies of trapped particles.

  10. First mass measurement at JYFLTRAP

    Energy Technology Data Exchange (ETDEWEB)

    Jokinen, A. [Department of Physics, PB 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland); Eronen, T. [Department of Physics, PB 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland); Hager, U. [Department of Physics, PB 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland); Hakala, J. [Department of Physics, PB 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland); Kolhinen, V. [Department of Physics, PB 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland); Kopecky, S. [Department of Physics, PB 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland); Rinta-Antila, S. [Department of Physics, PB 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland); Szerypo, J. [Department of Physics, PB 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland); Aeystoe, J. [Department of Physics, PB 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland)

    2004-12-27

    The first mass measurements at JYFLTRAP facility are reviewed. Those are also first ever direct mass measurements of the heaviest Zr-isotopes. Results are compared to atomic mass evaluation data and the recent calculations. The first TOF-resonances from high-precision trap and an implication to high-precision mass measurements are discussed.

  11. Ion cyclotron resonance detection techniques at TRIGA-TRAP

    Energy Technology Data Exchange (ETDEWEB)

    Knuth, K.; Eberhardt, K.; Ketelaer, J. [Johannes Gutenberg-Universitaet, Mainz (Germany); Beyer, T.; Blaum, K. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Ruprecht-Karls-Universitaet, Heidelberg (Germany); Block, M.; Herfurth, F. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Eibach, M.; Smorra, C. [Johannes Gutenberg-Universitaet, Mainz (Germany); Ruprecht-Karls-Universitaet, Heidelberg (Germany); Nagy, S. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany)

    2010-07-01

    In Penning trap mass spectrometry the mass of stored ions is obtained via a determination of the cyclotron frequency ({nu}{sub c}=qB/(2 {pi} m)), for which two different techniques are available. The destructive time-of-flight ion cyclotron resonance (TOF-ICR) technique, based on the measurement of the flight time of excited ions, is the established method for measurements on short-lived radionuclides. It is not ideally suited for rarely produced ion species, since typically some hundred ions are required for a single resonance spectrum. At the Penning trap mass spectrometer TRIGA-TRAP therefore a non-destructive narrow-band Fourier transform ion cyclotron resonance (FT-ICR) detection system is being developed. It is based on the detection of the image currents induced by the stored ions in the trap electrodes and will ultimately reach single ion sensitivity. TRIGA-TRAP also features broad-band FT-ICR detection for the coarse identification of the trap content. Additionally, the TOF-ICR detection system has been recently improved to utilize the Ramsey excitation technique to gain in precision, and the position information of the ion impact to further suppress background events in the final time-of-flight spectrum.

  12. Induction of trap formation in nematode-trapping fungi by bacteria-released ammonia.

    Science.gov (United States)

    Su, H N; Xu, Y Y; Wang, X; Zhang, K Q; Li, G H

    2016-04-01

    A total of 11 bacterial strains were assayed for bacteria-induced trap formation in the nematode-trapping fungus Arthrobotrys oligospora YMF1·01883 with two-compartmented Petri dish. These strains were identified on the basis of their 16S rRNA gene sequences. Volatile organic compounds (VOCs) of eight isolates were extracted using solid-phase micro-extraction (SPME) and their structures were identified based on gas chromatography-mass spectrometry (GC-MS). At the same time, all isolates were used for quantitative measurement of ammonia by the indophenol blue method. The effects of pure commercial compounds on inducement of trap formation in A. oligospora were tested. Taken together, results demonstrated that the predominant bacterial volatile compound inducing trap formation was ammonia. Meanwhile, ammonia also played a role in other nematode-trapping fungi, including Arthrobotrys guizhouensis YMF1·00014, producing adhesive nets; Dactylellina phymatopaga YMF1·01474, producing adhesive knobs; Dactylellina cionopaga YMF1·01472, producing adhesive columns and Drechslerella brochopaga YMF1·01829, producing constricting rings.

  13. Advanced Resolution Organic Molecule Analyzer (AROMA): Simulations, Development and Initial Testing of a Linear Ion Trap-Orbitrap Instrument for Space

    Science.gov (United States)

    Arevalo, R.; Danell, R. M.; Gundersen, C.; Hovmand, L.; Southard, A.; Tan, F.; Grubisic, A.; Brinckerhoff, W. B.; Getty, S. A.; Mahaffy, P.; Cottin, H.; Briois, C.; Colin, F.; Szopa, C.; Vuitton, V.; Makarov, A.; Reinhardt-Szyba, M.

    2016-10-01

    AROMA combines a linear ion trap and Orbitrap mass analyzer to enable: quantitative measurements of organic and inorganic compounds; selective isolation of targeted mass ranges; tandem mass spectrometry; and, ultrahigh mass resolution and accuracy.

  14. Atom trap trace analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Z.-T.; Bailey, K.; Chen, C.-Y.; Du, X.; Li, Y.-M.; O' Connor, T. P.; Young, L.

    2000-05-25

    A new method of ultrasensitive trace-isotope analysis has been developed based upon the technique of laser manipulation of neutral atoms. It has been used to count individual {sup 85}Kr and {sup 81}Kr atoms present in a natural krypton sample with isotopic abundances in the range of 10{sup {minus}11} and 10{sup {minus}13}, respectively. The atom counts are free of contamination from other isotopes, elements,or molecules. The method is applicable to other trace-isotopes that can be efficiently captured with a magneto-optical trap, and has a broad range of potential applications.

  15. Nonresonance adiabatic photon trap

    CERN Document Server

    Popov, S S; Burdakov, A V; Ushkova, M Yu

    2016-01-01

    Concept of high efficiency photon storage based on adiabatic confinement between concave mirrors is presented and experimentally investigated. The approach is insensitive to typical for Fabri-Perot cells requirements on quality of accumulated radiation, tolerance of resonator elements and their stability. Experiments have been carried out with the trap, which consists from opposed concave cylindrical mirrors and conjugated with them spherical mirrors. In result, high efficiency for accumulation of radiation with large angular spread and spectrum width has been confirmed. As radiation source a commercial fiber laser has been used.

  16. Atomic Coherent Trapping and Properties of Trapped Atom

    Institute of Scientific and Technical Information of China (English)

    YANG Guo-Jian; XIA Li-Xin; XIE Min

    2006-01-01

    Based on the theory of velocity-selective coherent population trapping, we investigate an atom-laser system where a pair of counterpropagating laser fields interact with a three-level atom. The influence of the parametric condition on the properties of the system such as velocity at which the atom is selected to be trapped, time needed for finishing the coherent trapping process, and possible electromagnetically induced transparency of an altrocold atomic medium,etc., is studied.

  17. Cryogenic resonator design for trapped ion experiments in Paul traps

    CERN Document Server

    Brandl, Matthias F; Monz, Thomas; Blatt, Rainer

    2016-01-01

    Trapping ions in Paul traps requires high radio-frequency voltages, which are generated using resonators. When operating traps in a cryogenic environment, an in-vacuum resonator showing low loss is crucial to limit the thermal load to the cryostat. In this study, we present a guide for the design and production of compact, shielded cryogenic resonators. We produced and characterized three different types of resonators and furthermore demonstrate efficient impedance matching of these resonators at cryogenic temperatures.

  18. Resonance methods in quadrupole ion traps

    Science.gov (United States)

    Snyder, Dalton T.; Peng, Wen-Ping; Cooks, R. Graham

    2017-01-01

    The quadrupole ion trap is widely used in the chemical physics community for making measurements on dynamical systems, both intramolecular (e.g. ion fragmentation reactions) and intermolecular (e.g. ion/molecule reactions). In this review, we discuss linear and nonlinear resonances in quadrupole ion traps, an understanding of which is critical for operation of these devices and interpretation of the data which they provide. The effect of quadrupole field nonlinearity is addressed, with important implications for promoting fragmentation and achieving unique methods of mass scanning. Methods that depend on ion resonances (i.e. matching an external perturbation with an ion's induced frequency of motion) are discussed, including ion isolation, ion activation, and ion ejection.

  19. About Black Holes Without Trapping Interior

    CERN Document Server

    Cabo-Montes de Oca, Alejandro; Cabo, Alejandro; Ayon, Eloy

    1999-01-01

    Physical arguments related with the existence of black hole solutions having a non trapping interior are discussed. Massive scalar fields interacting with gravity are considered. Interior asymptotic solutions showing a scalar field approaching a constant value at the horizon are given. It is argued that the coupled Einstein-Klein-Gordon equations can be satisfied in the sense of the generalized functions after removing a particular regularization designed for matching the interior solution with an external Scwartzschild spacetime. The scalar field appears as just avoiding the appearance of closed trapped surfaces while coming from the exterior region. It also follows that the usual space integral over the temporal- temporal components of energy-momnetum tensor in the internal region just gives the total proper mass associated to the external Schwartzschild solution, as it should be expected.

  20. EPR spin trapping of protein radicals

    DEFF Research Database (Denmark)

    Davies, Michael Jonathan; Hawkins, Clare Louise

    2004-01-01

    Electron paramagnetic resonance (EPR) spin trapping was originally developed to aid the detection of low-molecular-mass radicals formed in chemical systems. It has subsequently found widespread use in biology and medicine for the direct detection of radical species formed during oxidative stress...... and via enzymatic reactions. Over the last 15 years this technique has also found increasing use in detecting and identifying radicals formed on biological macromolecules as a result of either radical reactions or enzymatic processes. Though the EPR signals that result from the trapping of large, slowly...... tumbling radicals are often broad and relatively poor in distinctive features, a number of techniques have been developed that allow a wealth of information to be obtained about the nature, site, and reactions of such radicals. This article summarizes recent developments in this area and reviews selected...

  1. Nanofriction in cold ion traps.

    Science.gov (United States)

    Benassi, A; Vanossi, A; Tosatti, E

    2011-01-01

    Sliding friction between crystal lattices and the physics of cold ion traps are so far non-overlapping fields. Two sliding lattices may either stick and show static friction or slip with dynamic friction; cold ions are known to form static chains, helices or clusters, depending on the trapping conditions. Here we show, based on simulations, that much could be learnt about friction by sliding, through, for example, an electric field, the trapped ion chains over a corrugated potential. Unlike infinite chains, in which the theoretically predicted Aubry transition to free sliding may take place, trapped chains are always pinned. Yet, a properly defined static friction still vanishes Aubry-like at a symmetric-asymmetric structural transition, found for decreasing corrugation in both straight and zig-zag trapped chains. Dynamic friction is also accessible in ringdown oscillations of the ion trap. Long theorized static and dynamic one-dimensional friction phenomena could thus become accessible in future cold ion tribology.

  2. Instrumentation Upgrades to TITAN's Cooler Penning Trap

    Science.gov (United States)

    Lascar, Daniel; Titan Collaboration

    2016-09-01

    The use of Highly Charged Ions (HCIs) is critical to improving the precision of Penning trap mass measurements of nuclides with half-lives substantially less than 100 ms, but the process of charge breeding imparts an unacceptably high energy spread to the ion bunch sent to TITAN's precision Penning trap for mass measurement. TITAN's Cooler PEnning Trap (CPET) at TRIUMF in Vancouver, Canada was designed to cool HCIs with a plasma of simultaneously trapped electrons. CPET is currently undergoing commissioning offline at TRIUMF. In order to prepare CPET for full operation, several technical challenges associated with the use of electrons in a strong magnetic field had to be overcome. First among these was the detection of electrons outside of CPET. A novel, thin charge-collecting detector was successfully developed. Known as the mesh detector, it is charge-agnostic and can be made effectively transparent to allow for the passage of any charged particle at the user's request. The second challenge, moving CPET's electron source off the central beam axis was overcome by the creation of an electron source which would allow for electron injection into CPET and the passage of cooled ions out of CPET. CPET's 7 T solenoid generates a stray field far outside of the magnet's central bore that forced the design of a set of electron injection optics that bend, steer and focus the beam in three dimensions. Results from the successful installation of these upgrades as well as a report on future work will be discussed. This work was partially supported by NSERC, the CFI and the DFG.

  3. Non-target screening of Allura Red AC photodegradation products in a beverage through ultra high performance liquid chromatography coupled with hybrid triple quadrupole/linear ion trap mass spectrometry.

    Science.gov (United States)

    Gosetti, Fabio; Chiuminatto, Ugo; Mazzucco, Eleonora; Calabrese, Giorgio; Gennaro, Maria Carla; Marengo, Emilio

    2013-01-15

    The study deals with the identification of the degradation products formed by simulated sunlight photoirradiation in a commercial beverage that contains Allura Red AC dye. An UHPLC-MS/MS method, that makes use of hybrid triple quadrupole/linear ion trap, was developed. In the identification step the software tool information dependent acquisition (IDA) was used to automatically obtain information about the species present and to build a multiple reaction monitoring (MRM) method with the MS/MS fragmentation pattern of the species considered. The results indicate that the identified degradation products are formed from side-reactions and/or interactions among the dye and other ingredients present in the beverage (ascorbic acid, citric acid, sucrose, aromas, strawberry juice, and extract of chamomile flowers). The presence of aromatic amine or amide functionalities in the chemical structures proposed for the degradation products might suggest potential hazards to consumer health.

  4. Electron traps in semiconducting polymers: exponential versus Gaussian trap distribution

    NARCIS (Netherlands)

    Nicolai, H.T.; Mandoc, M.M.; Blom, P.W.M.

    2011-01-01

    The low electron currents in poly(dialkoxy-p-phenylene vinylene) (PPV) derivatives and their steep voltage dependence are generally explained by trap-limited conduction in the presence of an exponential trap distribution. Here we demonstrate that the electron transport of several PPV derivatives can

  5. Electron traps in semiconducting polymers : Exponential versus Gaussian trap distribution

    NARCIS (Netherlands)

    Nicolai, H. T.; Mandoc, M. M.; Blom, P. W. M.

    2011-01-01

    The low electron currents in poly(dialkoxy-p-phenylene vinylene) (PPV) derivatives and their steep voltage dependence are generally explained by trap-limited conduction in the presence of an exponential trap distribution. Here we demonstrate that the electron transport of several PPV derivatives can

  6. A Brief Presentation of Lanzhou Penning Trap Control System

    Institute of Scientific and Technical Information of China (English)

    田玉林; 黄文学; 王均英; 孙宇梁; 王玥; 朱志超; 赵建民; 徐瑚珊; 肖国青

    2012-01-01

    LPT (Lanzhou Penning Trap) is an ion-trap facility in Lanzhou, China. As ions can be cooled to an extremely small phase space and can be stored for a very long time, ion traps are a perfect instrument for high precision mass measurements. A system with specialized electronics for LPT is under construction now. This system could be used for voltage and timing control to make ions moving in a special mode, and the data acquisition and analysis online/offline could be achieved in the mean time. The requirements of control system, the distribution of hardware, the overview of software, and the latest progress of LPTCtrlSys (Lanzhou Penning Trap Control System) are presented.

  7. Introduction to the special issue on molecular spectroscopy in traps

    Science.gov (United States)

    Schlemmer, Stephan; Willitsch, Stefan; Steimle, Tim

    2017-02-01

    Trapping is a very versatile tool in many aspects of physics and chemistry. Trapping techniques are very well suited for spectroscopy studies due to the localization of the species of interest. As a result the particle density and the interaction times with photons are substantially increased with respect to other techniques. Therefore, both sensitivity and resolution benefit from this peculiar environment. Buffer gas or sympathetic cooling and mass selection are additional features applied in many trapping experiments. Thanks to these possibilities the number of spectroscopy publications based on these techniques increased substantially in the last decade. This special issue brings together some of the recent advancements in the field of molecular spectroscopy, mainly in ion traps, and demonstrates the large variety of applications, the very broad range of frequency coverage and the great potential for the field of molecular spectroscopy in general.

  8. The Penning trap system used by the BASE experiment

    CERN Multimedia

    Marcastel, Fabienne

    2015-01-01

    A cut-away schematic of the Penning trap system used by BASE. The experiment receives antiprotons from CERN's AD; negative hydrogen ions are formed during injection into the apparatus. The set-up works with only a pair of particles at a time, while a cloud of a few hundred others are held in the reservoir trap, for future use. Here, an antiproton is in the measurement trap, while the negative hydyrogen ion is in held by the downstream park electrode. When the antiproton has been measured, it is moved to the upstream park electrode and the hydrogen ion is brought in to the measurement trap. This is repeated thousands of times, enabling a high-precision comparison of the charge-to-mass ratios of the two particles.

  9. Experimental investigation on ionized ultracold molecules formed in a magneto-optical trap by time-of-flight mass spectroscopy%飞行时问质谱探测磁光阱中超冷分子离子的实验研究

    Institute of Scientific and Technical Information of China (English)

    元晋鹏; 姬中华; 杨艳; 张洪山; 赵延霆; 马杰; 汪丽蓉; 肖连团; 贾锁堂

    2012-01-01

    We use time-of-flight mass spectroscopy to detect the ultracold ground state Cs2 molecules formed directly by a photoassociation due to the trapping laser beams and repumping laser beam in a magneto-optical trap. We investigate the dependences of the Cs+ intensity on operating voltage of micro-channel-plate, accelerating field intensity and duration time of the accelerating field. The experimental results are consistent with theoretical fitting. We obtain the best optimal parameters suited to our experimental condition, which is important for the future experiment on ultracold molecule photoassociation and photoionization spectroscopy.%利用飞行时间质谱探测了由磁光阱中的俘获光和再泵浦光光缔合作用形成的超冷基态铯分子,研究了微通道板工作电压、加速电场强度和加速电场持续时间对铯分子离子信号强度的影响.实验结果与理论模型的拟合一致;获得了适合实验条件的最优化实验参数,为进一步研究超冷分子的光缔合光谱和光电离光谱奠定了实验基础.

  10. Quantum computing with trapped ions

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, R.J.

    1998-01-01

    The significance of quantum computation for cryptography is discussed. Following a brief survey of the requirements for quantum computational hardware, an overview of the ion trap quantum computation project at Los Alamos is presented. The physical limitations to quantum computation with trapped ions are analyzed and an assessment of the computational potential of the technology is made.

  11. The ALPHA antihydrogen trapping apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Amole, C. [Department of Physics and Astronomy, York University, Toronto ON Canada, M3J 1P3 (Canada); Andresen, G.B. [Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); Ashkezari, M.D. [Department of Physics, Simon Fraser University, Burnaby, BC Canada, V5A 1S6 (Canada); Baquero-Ruiz, M. [Department of Physics, University of California at Berkeley, Berkeley, CA 94720-7300 (United States); Bertsche, W. [Department of Physics, College of Science, Swansea University, Swansea SA2 8PP (United Kingdom); School of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom); The Cockcroft Institute, Warrington WA4 4AD (United Kingdom); Bowe, P.D. [Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); Butler, E. [Physics Department, CERN, CH-1211 Geneva 23 (Switzerland); Capra, A. [Department of Physics and Astronomy, York University, Toronto ON Canada, M3J 1P3 (Canada); Carpenter, P.T. [Department of Physics, Auburn University, Auburn, AL 36849-5311 (United States); Cesar, C.L. [Instituto de Física, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-972 (Brazil); Chapman, S. [Department of Physics, University of California at Berkeley, Berkeley, CA 94720-7300 (United States); Charlton, M.; Deller, A.; Eriksson, S. [Department of Physics, College of Science, Swansea University, Swansea SA2 8PP (United Kingdom); Escallier, J. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Fajans, J. [Department of Physics, University of California at Berkeley, Berkeley, CA 94720-7300 (United States); Friesen, T. [Department of Physics and Astronomy, University of Calgary, Calgary AB, Canada, T2N 1N4 (Canada); Fujiwara, M.C.; Gill, D.R. [TRIUMF, 4004 Wesbrook Mall, Vancouver BC, Canada V6T 2A3 (Canada); Gutierrez, A. [Department of Physics and Astronomy, University of British Columbia, Vancouver BC, Canada V6T 1Z4 (Canada); and others

    2014-01-21

    The ALPHA collaboration, based at CERN, has recently succeeded in confining cold antihydrogen atoms in a magnetic minimum neutral atom trap and has performed the first study of a resonant transition of the anti-atoms. The ALPHA apparatus will be described herein, with emphasis on the structural aspects, diagnostic methods and techniques that have enabled antihydrogen trapping and experimentation to be achieved.

  12. Accretion discs trapped near corotation

    NARCIS (Netherlands)

    D'Angelo, C.R.; Spruit, H.C.

    2012-01-01

    We show that discs accreting on to the magnetosphere of a rotating star can end up in a trapped state, in which the inner edge of the disc stays near the corotation radius, even at low and varying accretion rates. The accretion in these trapped states can be steady or cyclic; we explore these states

  13. Cryogenic silicon surface ion trap

    CERN Document Server

    Niedermayr, Michael; Kumph, Muir; Partel, Stefan; Edlinger, Johannes; Brownnutt, Michael; Blatt, Rainer

    2014-01-01

    Trapped ions are pre-eminent candidates for building quantum information processors and quantum simulators. They have been used to demonstrate quantum gates and algorithms, quantum error correction, and basic quantum simulations. However, to realise the full potential of such systems and make scalable trapped-ion quantum computing a reality, there exist a number of practical problems which must be solved. These include tackling the observed high ion-heating rates and creating scalable trap structures which can be simply and reliably produced. Here, we report on cryogenically operated silicon ion traps which can be rapidly and easily fabricated using standard semiconductor technologies. Single $^{40}$Ca$^+$ ions have been trapped and used to characterize the trap operation. Long ion lifetimes were observed with the traps exhibiting heating rates as low as $\\dot{\\bar{n}}=$ 0.33 phonons/s at an ion-electrode distance of 230 $\\mu$m. These results open many new avenues to arrays of micro-fabricated ion traps.

  14. Detection of Isotopes of Mercury Ions by Resonant Ejection in Paul Trap

    Institute of Scientific and Technical Information of China (English)

    WANG Wen-Ming; SHE Lei; LI Jiao-Mei; GAO Ke-Lin

    2007-01-01

    A simple method to detect mercury ions confined in a Paul trap has been developed by resonant ejection. In this method, frequency of the additional ejection ac voltage is scanned instead of the amplitude of the rf drive voltage in conventional methods. It is possible not only to observe the spectra of the secular oscillation of the trapped ions directly, but also to eject the confined ions from the trap mass-selectively.

  15. Pumped helium system for cooling positron and electron traps to 1.2 K

    Science.gov (United States)

    Wrubel, J.; Gabrielse, G.; Kolthammer, W. S.; Larochelle, P.; McConnell, R.; Richerme, P.; Grzonka, D.; Oelert, W.; Sefzick, T.; Zielinski, M.; Borbely, J. S.; George, M. C.; Hessels, E. A.; Storry, C. H.; Weel, M.; Müllers, A.; Walz, J.; Speck, A.

    2011-06-01

    Extremely precise tests of fundamental particle symmetries should be possible via laser spectroscopy of trapped antihydrogen ( H¯) atoms. H¯ atoms that can be trapped must have an energy in temperature units that is below 0.5 K—the energy depth of the deepest magnetic traps that can currently be constructed with high currents and superconducting technology. The number of atoms in a Boltzmann distribution with energies lower than this trap depth depends sharply upon the temperature of the thermal distribution. For example, ten times more atoms with energies low enough to be trapped are in a thermal distribution at a temperature of 1.2 K than for a temperature of 4.2 K. To date, H¯ atoms have only been produced within traps whose electrode temperature is 4.2 K or higher. A lower temperature apparatus is desirable if usable numbers of atoms that can be trapped are to eventually be produced. This report is about the pumped helium apparatus that cooled the trap electrodes of an H¯ apparatus to 1.2 K for the first time. Significant apparatus challenges include the need to cool a 0.8 m stack of 37 trap electrodes separated by only a mm from the substantial mass of a 4.2 K Ioffe trap and the substantial mass of a 4.2 K solenoid. Access to the interior of the cold electrodes must be maintained for antiprotons, positrons, electrons and lasers.

  16. The trapped human experiment.

    Science.gov (United States)

    Huo, R; Agapiou, A; Bocos-Bintintan, V; Brown, L J; Burns, C; Creaser, C S; Devenport, N A; Gao-Lau, B; Guallar-Hoyas, C; Hildebrand, L; Malkar, A; Martin, H J; Moll, V H; Patel, P; Ratiu, A; Reynolds, J C; Sielemann, S; Slodzynski, R; Statheropoulos, M; Turner, M A; Vautz, W; Wright, V E; Thomas, C L P

    2011-12-01

    This experiment observed the evolution of metabolite plumes from a human trapped in a simulation of a collapsed building. Ten participants took it in turns over five days to lie in a simulation of a collapsed building and eight of them completed the 6 h protocol while their breath, sweat and skin metabolites were passed through a simulation of a collapsed glass-clad reinforced-concrete building. Safety, welfare and environmental parameters were monitored continuously, and active adsorbent sampling for thermal desorption GC-MS, on-line and embedded CO, CO(2) and O(2) monitoring, aspirating ion mobility spectrometry with integrated semiconductor gas sensors, direct injection GC-ion mobility spectrometry, active sampling thermal desorption GC-differential mobility spectrometry and a prototype remote early detection system for survivor location were used to monitor the evolution of the metabolite plumes that were generated. Oxygen levels within the void simulator were allowed to fall no lower than 19.1% (v). Concurrent levels of carbon dioxide built up to an average level of 1.6% (v) in the breathing zone of the participants. Temperature, humidity, carbon dioxide levels and the physiological measurements were consistent with a reproducible methodology that enabled the metabolite plumes to be sampled and characterized from the different parts of the experiment. Welfare and safety data were satisfactory with pulse rates, blood pressures and oxygenation, all within levels consistent with healthy adults. Up to 12 in-test welfare assessments per participant and a six-week follow-up Stanford Acute Stress Response Questionnaire indicated that the researchers and participants did not experience any adverse effects from their involvement in the study. Preliminary observations confirmed that CO(2), NH(3) and acetone were effective markers for trapped humans, although interactions with water absorbed in building debris needed further study. An unexpected observation from the NH(3

  17. Determination of 2 Methylisoborneol and Geosmin in Water by Purge and Trap Technology with Gas Chromatography/Mass Spectrometry(GC/MS)%吹扫捕集气相色谱-质谱联用测定水中二甲基异莰醇和土臭素

    Institute of Scientific and Technical Information of China (English)

    乐洋; 孙坚伟

    2015-01-01

    该文介绍了吹扫捕集气相色谱—质谱联用测定地表水/饮用水中痕量嗅味物质二甲基异莰醇和土臭素。采用吹扫捕集装置对样品中目标分析物进行富集,再用盐化和红外加热提高吹扫效果[1];用VF 624 ms的毛细管色谱柱进行分离,质谱检测定量。结果表明线性相关系数均大于0.99,RSD小于10%,加标回收率为90%~110%,最低检出限满足GB 5749—2006中的检测要求[2]。%Determination of 2 methylisoborneol and geosmin in drinking water and surface water by purge and trap capillary column gas chromatography/mass spectrometry was introduced in this paper.Samples of 2 methylisoborneol and geosmin in the water were enriched by purge and trap with Na2 SO4 and infrared heating.The samples were separated by the capillary column VF 624 ms, and detected by mass spectrometry.The results show the linear coefficients of all the calibration curves are more than 0.99 and RSD of all are less than 10%.The recovery rates are 90%~110%.The detection limit meets the requirement of GB 5749—2006.

  18. Screening and Confirmation of Phthalates in Food Contact Materials by Hybrid Linear Ion Trap/Orbitrap Mass Spectrometry%食品接触材料中邻苯二甲酸酯的LTQ-Orbitrap组合式高分辨质谱快速筛查和确证

    Institute of Scientific and Technical Information of China (English)

    王晓兵; 丁利; 朱绍华; 戴华; 许宙; 焦艳娜; 王利岳

    2011-01-01

    A fast screening and conformation method of phthalates in food contact materials based on liquid chromatography mass spectrometry using a linear ion trap-orbitrap hybrid instrument at high mass resolution(HPLC-LTQ-Oribitrap/MS) was developed.Accelerated s%建立了食品接触材料中邻苯二甲酸酯快速筛查确证的高效液相色谱-高分辨质谱法(HPLC-LTQ-Orbi-trap/MS)。实验中采用加速溶剂萃取(ASE)法为样品前处理手段,优化了萃取溶剂、萃取温度、静态萃取时间等实验参数,提高了食品接触材料中邻苯二甲酸酯的提取效率。采用高分辨质谱有效地去除了基体干扰,通过静电场轨道阱全扫描得到的精确相对分子质量进行了化合物的定量,用离子阱的二级质谱图对未知化合物进行了进一步确证。结果表明:邻苯二甲酸酯的检测限为1 ng/mL;该方法的加标回收率为89.8%~101.3%,

  19. Microwave-assisted purge-and-trap extraction device coupled with gas chromatography and mass spectrometry for the determination of five predominant odors in sediment, fish tissues, and algal cells.

    Science.gov (United States)

    Deng, Xuwei; Xie, Ping; Qi, Min; Liang, Gaodao; Chen, Jun; Ma, Zhimei; Jiang, Yan

    2012-01-06

    Off-flavors are among the most troublesome compounds in the environment worldwide. The lack of a viable theory for studying the sources, distribution, and effect of odors has necessitated the accurate measurement of odors from environmental compartments. A rapid and flexible microwave-assisted purge-and-trap extraction device for simultaneously determining five predominant odors, namely, dimethyltrisulfide, 2-methylisoborneol, geosmin, β-cyclocitral and β-ionone, from the primary sources and sinks is demonstrated. This instrument facilitates the extraction and concentration of odors from quite different matrices simultaneously. This device is a solvent-free automated system that does not require cleaning and is timesaving. The calibration curves of the five odor compounds showed good linearity in the range of 1-500 ng/L, with correlation coefficients above 0.999 (levels=7) and with residuals ranging from approximately 77% to 104%. The limits of detection (S/N=3) were below 0.15 ng/L in algae sample and 0.07 ng/g in sediment and fish tissue samples. The relative standard deviations were between 2.65% and 7.29% (n=6). Thus the proposed design is ready for rapid translation into a standard analytical tool and is useful for multiple applications in the analysis of off-flavors.

  20. 1986-87 Annual Trapping Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Annual Trapping Plan for the 1986-87 trapping season at Clarence Cannon NWR outlines rules and regulations for the trapping of beaver, muskrat, raccoon,...

  1. Reducing Space Charge Effects in a Linear Ion Trap by Rhombic Ion Excitation and Ejection

    Science.gov (United States)

    Zhang, Xiaohua; Wang, Yuzhuo; Hu, Lili; Guo, Dan; Fang, Xiang; Zhou, Mingfei; Xu, Wei

    2016-07-01

    Space charge effects play important roles in ion trap operations, which typically limit the ion trapping capacity, dynamic range, mass accuracy, and resolving power of a quadrupole ion trap. In this study, a rhombic ion excitation and ejection method was proposed to minimize space charge effects in a linear ion trap. Instead of applying a single dipolar AC excitation signal, two dipolar AC excitation signals with the same frequency and amplitude but 90° phase difference were applied in the x- and y-directions of the linear ion trap, respectively. As a result, mass selective excited ions would circle around the ion cloud located at the center of the ion trap, rather than go through the ion cloud. In this work, excited ions were then axially ejected and detected, but this rhombic ion excitation method could also be applied to linear ion traps with ion radial ejection capabilities. Experiments show that space charge induced mass resolution degradation and mass shift could be alleviated with this method. For the experimental conditions in this work, space charge induced mass shift could be decreased by ~50%, and the mass resolving power could be improved by ~2 times at the same time.

  2. Matrix-assisted laser desorption/ionization time-of-flight and nano-electrospray ionization ion trap mass spectrometric characterization of 1-cyano-2-substituted-benz[f]isoindole derivatives of peptides for fluorescence detection

    DEFF Research Database (Denmark)

    Linnemayr, K; Brückner, A; Körner, R;

    1999-01-01

    A series of hexa- to decapeptides (molecular mass range 800-1200) were labeled with naphthalene-2,3-dicarboxaldehyde, which preferentially reacts with the primary amino groups of a peptide. A highly stable peptide conjugate is formed, which allows selective analysis by fluorescence at excitation...

  3. Feedback traps for virtual potentials

    CERN Document Server

    Gavrilov, Momčilo

    2016-01-01

    Feedback traps are tools for trapping and manipulating single charged objects, such as molecules in solution. An alternative to optical tweezers and other single-molecule techniques, they use feedback to counteract the Brownian motion of a molecule of interest. The trap first acquires information about a molecule's position and then applies an electric feedback force to move the molecule. Since electric forces are stronger than optical forces at small scales, feedback traps are the best way to trap single molecules without "touching" them. Feedback traps can do more than trap molecules: They can also subject a target object to forces that are calculated to be the gradient of a desired potential function U(x). If the feedback loop is fast enough, it creates a virtual potential whose dynamics will be very close to those of a particle in an actual potential U(x). But because the dynamics are entirely a result of the feedback loop--absent the feedback, there is only an object diffusing in a fluid--we are free to ...

  4. Trapping tsetse flies on water

    Directory of Open Access Journals (Sweden)

    Laveissière C.

    2011-05-01

    Full Text Available Riverine tsetse flies such as Glossina palpalis gambiensis and G. tachinoides are the vectors of human and animal trypanosomoses in West Africa. Despite intimate links between tsetse and water, to our knowledge there has never been any attempt to design trapping devices that would catch tsetse on water. In mangrove (Guinea one challenging issue is the tide, because height above the ground for a trap is a key factor affecting tsetse catches. The trap was mounted on the remains of an old wooden dugout, and attached with rope to nearby branches, thereby allowing it to rise and fall with the tide. Catches showed a very high density of 93.9 flies/”water-trap”/day, which was significantly higher (p < 0.05 than all the catches from other habitats where the classical trap had been used. In savannah, on the Comoe river of South Burkina Faso, the biconical trap was mounted on a small wooden raft anchored to a stone, and catches were compared with the classical biconical trap put on the shores. G. p. gambiensis and G. tachinoides densities were not significantly different from those from the classical biconical one. The adaptations described here have allowed to efficiently catch tsetse on the water, which to our knowledge is reported here for the first time. This represents a great progress and opens new opportunities to undertake studies on the vectors of trypanosomoses in mangrove areas of Guinea, which are currently the areas showing the highest prevalences of sleeping sickness in West Africa. It also has huge potential for tsetse control using insecticide impregnated traps in savannah areas where traps become less efficient in rainy season. The Guinean National control programme has already expressed its willingness to use such modified traps in its control campaigns in Guinea, as has the national PATTEC programme in Burkina Faso during rainy season.

  5. Testing Lorentz and CPT Symmetries in Penning Traps

    CERN Document Server

    Ding, Yunhua

    2016-01-01

    A modified Dirac equation with general Lorentz- and CPT-violating operators in the electromagnetic field is studied. Constraints on and possible sensitivities to Lorentz-violating coefficients in the nonminimal sector up to mass-dimension six can be obtained by analyzing Penning-trap results involving anomaly frequencies.

  6. Non-destructive ion detection at TRIGA-TRAP

    Energy Technology Data Exchange (ETDEWEB)

    Eibach, Martin; Smorra, Christian [Institut fuer Kernchemie, Universitaet Mainz (Germany); Physikalisches Institut, Universitaet Heidelberg (Germany); Beyer, Thomas; Ketter, Jochen; Blaum, Klaus [Physikalisches Institut, Universitaet Heidelberg (Germany); Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Block, Michael; Herfurth, Frank [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Eberhardt, Klaus [Institut fuer Kernchemie, Universitaet Mainz (Germany); Ketelaer, Jens; Knuth, Konstantin [Institut fuer Physik, Universitaet Mainz (Germany); Nagy, Szilard [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany)

    2010-07-01

    Tests of nuclear mass models, studies of the nuclear structure of heavy elements and calculations of the astrophysical r-process require high precision atomic mass data. For this purpose the double Penning trap mass spectrometer TRIGA-TRAP has recently been set up in order to explore the less-known neutron-rich area of the nuclide chart. Certain nuclides of interest are produced by thermal neutron-induced fission of an actinoide target with low rates, in the order of a few nuclides per second or less. Thus, the implementation of very efficient means of detection are necessary, such as the non-destructive Fourier transform ion cyclotron resonance (FT-ICR) technique where ultimately a single trapped ion, with a half-life of longer than one second is sufficient for the entire mass measurement. The present status of the implementation of the FT-ICR detection at TRIGA-TRAP is presented. The potential benefit for other experiments is discussed.

  7. A reservoir trap for antiprotons

    CERN Document Server

    Smorra, Christian; Franke, Kurt; Nagahama, Hiroki; Schneider, Georg; Higuchi, Takashi; Van Gorp, Simon; Blaum, Klaus; Matsuda, Yasuyuki; Quint, Wolfgang; Walz, Jochen; Yamazaki, Yasunori; Ulmer, Stefan

    2015-01-01

    We have developed techniques to extract arbitrary fractions of antiprotons from an accumulated reservoir, and to inject them into a Penning-trap system for high-precision measurements. In our trap-system antiproton storage times > 1.08 years are estimated. The device is fail-safe against power-cuts of up to 10 hours. This makes our planned comparisons of the fundamental properties of protons and antiprotons independent from accelerator cycles, and will enable us to perform experiments during long accelerator shutdown periods when background magnetic noise is low. The demonstrated scheme has the potential to be applied in many other precision Penning trap experiments dealing with exotic particles.

  8. A New Atom Trap The Annular Shell Atom Trap (ASAT)

    CERN Document Server

    Pilloff, H S; Pilloff, Herschel S.; Horbatsch, Marko

    2002-01-01

    In the course of exploring some aspects of atom guiding in a hollow, optical fiber, a small negative potential energy well was found just in front of the repulsive or guiding barrier. This results from the optical dipole and the van der Waals potentials. The ground state for atoms bound in this negative potential well was determined by numerically solving the Schrodinger eq. and it was found that this negative well could serve as an atom trap. This trap is referred to as the Annular Shell Atom Trap or ASAT because of the geometry of the trapped atoms which are located in the locus of points defining a very thin annular shell just in front of the guiding barrier. A unique feature of the ASAT is the compression of the atoms from the entire volume to the volume of the annular shell resulting in a very high density of atoms in this trap. This trap may have applications to very low temperatures using evaporative cooling and possibly the formation of BEC. Finally, a scheme is discussed for taking advantage of the d...

  9. Innovation: the classic traps.

    Science.gov (United States)

    Kanter, Rosabeth Moss

    2006-11-01

    these traps.

  10. Magneto optical trapping of Barium

    CERN Document Server

    De, S; Jungmann, K; Willmann, L

    2008-01-01

    First laser cooling and trapping of the heavy alkaline earth element barium has been achieved based on the strong 6s$^2$ $^1$S$_0$ - 6s6p $^1$P$_1$ transition for the main cooling. Due to the large branching into metastable D-states several additional laser driven transitions are required to provide a closed cooling cycle. A total efficiency of $0.4(1) \\cdot 10^{-2}$ for slowing a thermal atomic beam and capturing atoms into a magneto optical trap was obtained. Trapping lifetimes of more than 1.5 s were observed. This lifetime is shortened at high laser intensities by photo ionization losses. The developed techniques will allow to extend significantly the number of elements that can be optically cooled and trapped.

  11. Trapping Triatominae in Silvatic Habitats

    Directory of Open Access Journals (Sweden)

    Noireau François

    2002-01-01

    Full Text Available Large-scale trials of a trapping system designed to collect silvatic Triatominae are reported. Live-baited adhesive traps were tested in various ecosystems and different triatomine habitats (arboreal and terrestrial. The trials were always successful, with a rate of positive habitats generally over 20% and reaching 48.4% for palm trees of the Amazon basin. Eleven species of Triatominae belonging to the three genera of public health importance (Triatoma, Rhodnius and Panstrongylus were captured. This trapping system provides an effective way to detect the presence of triatomines in terrestrial and arboreal silvatic habitats and represents a promising tool for ecological studies. Various lines of research are contemplated to improve the performance of this trapping system.

  12. Development and validation of highly selective screening and confirmatory methods for the qualitative forensic analysis of organic explosive compounds with high performance liquid chromatography coupled with (photodiode array and) LTQ ion trap/Orbitrap mass spectrometric detections (HPLC-(PDA)-LTQOrbitrap).

    Science.gov (United States)

    Xu, Xiaoma; Koeberg, Mattijs; Kuijpers, Chris-Jan; Kok, Eric

    2014-01-01

    An LTQ-Orbitrap FTMS is a new (hybrid) mass spectrometric (MS) analyzer. It allows for the acquisition of full scan MS(n) (n-stage fragmentations, n=1-n) spectra with the linear ion trap detector (LTQ) at high speed and/or with the Fourier Transform-detector (Orbitrap) with ultra high mass resolution (>60,000 at m/zphoto diode array (PDA) detection. Two methods for the forensic screening and confirmation of all common trace explosives in post-blast residues have been developed on this instrument using atmospheric pressure chemical ionization (APCI). In one run, the nitrogen-containing explosives are analyzed with the combination of "LC-(PDA)-APCI(-)-LTQ MS(2)/Orbitrap FTMS" (Method 1). In another run, peroxide explosives are analyzed with "LC-APCI(+)-LTQ MS(2)/Orbitrap FTMS" (Method 2). The performance of both methods has been validated according to procedures defined in the EU COMMISSION DECISION implementing Council Directive 96/23/EC concerning the performance of analytical methods and the interpretation of results (DC 2002/657/EC) and other standards (NEN 17025 and NEN 7777). The methods are highly selective due to the simultaneous utilization of the Orbitrap FTMS and LTQ MS(2), both of which are highly selective detectors Tested explosive compounds can be detected in the molecular ion form by the Orbitrap analyzer with minimal mass interference in different matrices when using an extremely narrow mass tolerance detection window (≤2ppm). The identification of a detected compound follows an identification point system. Experimental results show that almost all explosive compounds meet the confirmation criteria (minimum 4 points) required for the positive identification by the DC 2002/657/EC.

  13. Rapid, high performance method for the determination of vitamin K(1), menaquinone-4 and vitamin K(1) 2,3-epoxide in human serum and plasma using liquid chromatography-hybrid quadrupole linear ion trap mass spectrometry.

    Science.gov (United States)

    Gentili, Alessandra; Cafolla, Arturo; Gasperi, Tecla; Bellante, Simona; Caretti, Fulvia; Curini, Roberta; Fernández, Virginia Pérez

    2014-04-18

    Unlike the other fat-soluble vitamins, vitamin K circulates in the human bloodstream at very low levels because of a low intake in the diet. Mammals have developed an efficient recycling system, known as vitamin K-epoxide cycle, which involve quinone, hydroquinone and epoxide forms of the vitamin. Phylloquinone (K(1)) is the main homologue, while menaquinone-4 (MK-4) is both a member of the vitamin K(2) family and metabolite of K(1) in extra-hepatic tissues. Notwithstanding the recent advances, many aspects of the complex vitamin K physiology still remain to be investigated. Therefore, there is a critical need to develop more reliable analytical methods for determining the vitamin K and its metabolites in biological fluids and tissues. Nevertheless, relatively low concentrations, unavailability of some authentic standards and occurrence of interfering lipids make this a challenging task. The method proposed in the present paper can directly and accurately estimate K(1), K(1) 2,3-epoxide (K(1)O), and MK-4 in human serum and plasma at concentrations in the ng/L-μg/L range, using labelled internal standards and a quadrupole linear ion trap instrument operated in multiple reaction monitoring (MRM) mode. High sensitivity was achieved by removing signal "endogenous suppressors" and making the composition of the non-aqueous mobile phase suitable to support the positive atmospheric pressure chemical ionization of the analytes. An excellent selectivity resulted from the combination of some factors: the MRM acquisition, the adoption of an identification point system, an extraction optimized to remove most of the lipids and a tandem-C18 column-system necessary to separate isobaric interferences from analytes. The method was validated according to the Food and Drug Administration (FDA) guidelines and its accuracy was assessed by analysing 9 samples from the Vitamin K External Quality Assessment Scheme (KEQAS). Its feasibility in evaluating vitamin K status in human serum was

  14. Mass measurements on radioactive isotopes using the ISOLTRAP spectrometer

    CERN Document Server

    Dilling, J; Kluge, H J; Kohl, A; Lamour, E; Marx, G; Schwarz, S C; Bollen, G; Kellerbauer, A G; Moore, R B; Henry, S

    2000-01-01

    ISOLTRAP is a Penning trap mass spectrometer installed at the on line isotope separator ISOLDE at CERN. Direct measurements of the masses of short lived radio isotopes are performed using the existing triple trap system. This consists of three electromagnetic traps in tandem: a Paul trap to accumulate and bunch the 60 keV dc beam, a Penning trap for cooling and isobar separation, and a precision Penning trap for the determination of the masses by cyclotron resonance. Measurements of masses of unknown mercury isotopes and in the vicinity of doubly magic /sup 208/Pb are presented, all with an accuracy of delta m/m approximately=1*10/sup -7/. Developments to replace the Paul trap by a radiofrequency quadrupole ion guide system to increase the collection efficiency are presently under way and the status is presented. (10 refs).

  15. Characterization and simultaneous quantification of biological aporphine alkaloids in Litsea cubeba by HPLC with hybrid ion trap time-of-flight mass spectrometry and HPLC with diode array detection.

    Science.gov (United States)

    Zhang, Shuiying; Zhang, Qian; Guo, Qiang; Zhao, Yunfang; Gao, Xiaoli; Chai, Xingyun; Tu, Pengfei

    2015-08-01

    The root and rhizome of Litsea cubeba (Lour) Pers., named 'Dou-chi-jiang' in Chinese, has been traditionally used for treatment of cardiovascular and cerebrovascular diseases, rheumatic arthralgia, and other diseases in China. Aporphine alkaloids are its characteristic ingredients and responsible for its bioactivities, especially anti-inflammatory and analgesic effects. A sensitive and reliable high-performance liquid chromatography with diode array detection-tandem mass spectrometry method was developed for characterization and simultaneous determination of biological aporphine alkaloids in 'Dou-chi-jiang'. The optimized chromatographic conditions were performed on an Eclipse XDB C18 column with a gradient of acetonitrile/water containing 0.1% formic acid as the mass spectrometry mobile phase and acetonitrile/water containing 0.2% diethylamine (pH 3.10, adjusted by acetic acid) as the liquid chromatography mobile phase. The fragmentation pathways by loss of CO, ·CH3 , ·NH3 , and ·NH2 CH3 were detected as characteristic for aporphine alkaloids. Based on these characteristics, total 12 analogues were identified. The quantification method was validated in terms of linearity, precision, and accuracy for six major aporphine alkaloids, which was successfully applied for simultaneous determination in ten batches of samples. The established method is simple, rapid, and specific for characterization and quantitation of aporphine alkaloids in 'Dou-chi-jiang' and other traditional Chinese medicines rich in this kind of ingredient.

  16. Metabolite identification of seven active components of Huan-Nao-Yi-Cong-Fang in rat plasma using high-performance liquid chromatography combined with hybrid ion trap/time-of-flight mass spectrometry.

    Science.gov (United States)

    Wang, Minchao; Lu, Yanzhen; Liu, Jiangang; Li, Hao; Wei, Yun

    2016-02-01

    Huan-Nao-Yi-Cong-Fang (HNYCF) is a potential prescription in treating Alzheimer's disease. Seven constituents [ferulic acid (FA), 2,3,5,4'-tetrahydroxystilbene-2-O-β-d-glucoside (THSG), berberine hydrochloride (BHCl), emodin, ginsenoside Rg1 (Rg1), ginsenoside Re (Re) and ginsenoside Rb1 (Rb1)] have been used as quality chemical markers of HNYCF owing to their biological significance and high contents in crude plant materials. This study explored the metabolites of the seven bioactive components in rat plasma to give useful data for further study of the action mechanism of HNYCF. LC/MS-IT-TOF was used to simultaneously characterize the metabolites of the seven components. Using the combination of MetID Solution 1.0 software and accurate mass measurements, the metabolites of HNYCF were reliably characterized. Their structures were elucidated based on the accurate MS(2) spectra and comparisons of their changes in accurate molecular masses and fragment ions with those of parent compounds. A total of five parent active compounds (BHCl, emodin, Rg1, Rb1 and Re) and 10 metabolites were found from the rat plasma 2 h after oral administration of HNYCF dosage, of which two metabolites of emodin were observed for the first time. The proposed metabolic pathways of the bioactive components in the rat plasma are helpful for further studies on the pharmacokinetics and real active compound forms of this drug.

  17. Weighing of trapped ion crystals and its applications

    CERN Document Server

    Sheridan, Kevin

    2011-01-01

    We have developed a novel scheme to measure the secular motion of trapped ions. Employing pulsed excitation and analysis of the fluorescence of laser cooled ions, the COM-mode frequency of single as well as entire ion crystals can be measured to an accuracy of better than 100 Hz within an interrogation on the order of seconds, limited only by the fluorescence collection efficiency and the background noise. We have used this method to measure the mass of ions and observed charge exchange collisions between trapped calcium isotopes.

  18. Photoassociative Production and Trapping of Ultracold KRb Molecules

    CERN Document Server

    Wang, D; Stone, M F; Nikolayeva, O; Wang, H; Hattaway, B; Gensemer, S D; Gould, P L; Eyler, E E; Stwalley, W C

    2004-01-01

    We have produced ultracold heteronuclear KRb molecules by the process of photoassociation in a two-species magneto-optical trap. Following decay of the photoassociated KRb*, the molecules are detected using two-photon ionization and time-of-flight mass spectroscopy of KRb$^+$. A portion of the metastable triplet molecules thus formed are magnetically trapped. Photoassociative spectra down to 91 cm$^{-1}$ below the K(4$s$) + Rb (5$p_{1/2}$) asymptote have been obtained. We have made assignments to all eight of the attractive Hund's case (c) KRb* potential curves in this spectral region.

  19. Study of the discharge gas trapping during thin film growth

    CERN Document Server

    Calatroni, Sergio; Anderle, M; Benvenuti, Cristoforo; Carver, J; Chiggiato, P; Neupert, H; Vollenberg, W

    2001-01-01

    Discharge gas trapping in thin films produced by sputtering is known to be due to high energy neutrals bouncing back from the cathode. Qualitatively, the phenomenon is enhanced by raising the discharge voltage and is strongly dependent on the atomic masses of the discharge gas and of the cathode material. In addition to these known effects it is shown that, for a given gas, the trapped amount decreases with increasing the melting temperature of the deposited material. The results obtained both by sample melting and laser ablation are presented and discussed.

  20. Ultraviolet Photodissociation Induced by Light-Emitting Diodes in a Planar Ion Trap.

    Science.gov (United States)

    Holden, Dustin D; Makarov, Alexander; Schwartz, Jae C; Sanders, James D; Zhuk, Eugene; Brodbelt, Jennifer S

    2016-09-26

    The first application of light-emitting diodes (LEDs) for ultraviolet photodissociation (UVPD) mass spectrometry is reported. LEDs provide a compact, low cost light source and have been incorporated directly into the trapping cell of an Orbitrap mass spectrometer. MS/MS efficiencies of over 50 % were obtained using an extended irradiation period, and UVPD was optimized by modulating the ion trapping parameters to maximize the overlap between the ion cloud and the irradiation volume.

  1. Microinstrument gradient-force optical trap.

    Science.gov (United States)

    Collins, S D; Baskin, R J; Howitt, D G

    1999-10-01

    A micromachined fiber-optic trap is presented. The trap consists of four single-mode, 1064-nm optical intersection. The beam fibers mounted in a micromachined silicon and glass housing. Micromachining provides the necessary precision to align the four optical fibers so that the outputs have a common intersection forms a strong three-dimensional gradient-force trap with trapping forces comparable with that of optical tweezers. Characterization of the multibeam fiber trap is illustrated for capture of polystyrene microspheres, computer simulations of the trap stiffness, and experimental determination of the trapping forces.

  2. Dense stellar matter with trapped neutrinos under strong magnetic fields

    CERN Document Server

    Rabhi, A

    2009-01-01

    We investigate the effects of strong magnetic fields on the equation of state of dense stellar neutrino-free and neutrino-trapped matter. Relativistic nuclear models both with constant couplings (NLW) and with density dependent parameters (DDRH) and including hyperons are considered . It is shown that at low densities neutrinos are suppressed in the presence of the magnetic field. The magnetic field reduces the strangeness fraction of neutrino-free matter and increases the strangeness fraction of neutrino-trapped matter. The mass-radius relation of stars described by these equations of state are determined. The magnetic field makes the overall equation of state stiffer and the stronger the field the larger the mass of maximum mass star and the smaller the baryon density at the center of the star. As a consequence in the presence of strong magnetic fields the possibility that a protoneutron star evolves to a blackhole is smaller.

  3. Super-Earths as Failed Cores in Orbital Migration Traps

    Science.gov (United States)

    Hasegawa, Yasuhiro

    2016-11-01

    I explore whether close-in super-Earths were formed as rocky bodies that failed to grow fast enough to become the cores of gas giants before the natal protostellar disk dispersed. I model the failed cores’ inward orbital migration in the low-mass or type I regime to stopping points at distances where the tidal interaction with the protostellar disk applies zero net torque. The three kinds of migration traps considered are those due to the dead zone's outer edge, the ice line, and the transition from accretion to starlight as the disk's main heat source. As the disk disperses, the traps move toward final positions near or just outside 1 au. Planets at this location exceeding about 3 M ⊕ open a gap, decouple from their host traps, and migrate inward in the high-mass or type II regime to reach the vicinity of the star. I synthesize the population of planets that formed in this scenario, finding that a fraction of the observed super-Earths could have been failed cores. Most super-Earths that formed this way have more than 4 M ⊕, so their orbits when the disks dispersed were governed by type II migration. These planets have solid cores surrounded by gaseous envelopes. Their subsequent photoevaporative mass loss is most effective for masses originally below about 6 M ⊕. The failed core scenario suggests a division of the observed super-Earth mass-radius diagram into five zones according to the inferred formation history.

  4. A magnetic particle micro-trap for large trapping surfaces

    KAUST Repository

    Gooneratne, Chinthaka P.

    2012-01-08

    Manipulation of micron-size magnetic particles of the superparamagnetic type contributes significantly in many applications like controlling the antibody/antigen binding process in immunoassays. Specifically, more target biomolecules can be attached/tagged and analyzed since the three dimensional structure of the magnetic particles increases the surface to volume ratio. Additionally, such biomolecular-tagged magnetic particles can be easily manipulated by an external magnetic field due to their superparamagnetic behavior. Therefore, magnetic particle- based immunoassays are extensively applied in micro-flow cytometry. The design of a square-loop micro-trap as a magnetic particle manipulator as well as numerical and experimental analysis is presented. Experimental results showed that the micro-trap could successfully trap and concentrate magnetic particles from a large to a small area with a high spatial range.

  5. Characteristics of Ion Activation and Collision Induced Dissociation Using Digital Ion Trap Technology

    Science.gov (United States)

    Xu, Fuxing; Dang, Qiankun; Dai, Xinhua; Fang, Xiang; Wang, Yuanyuan; Ding, Li; Ding, Chuan-Fan

    2016-08-01

    Collision induced dissociation (CID) is one of the most established techniques for tandem mass spectrometry analysis. The CID of mass selected ion could be realized by ion resonance excitation with a digital rectangular waveform. The method is simple, and highly efficient CID result could be obtained by optimizing the experimental parameters, such as digital waveform voltage, frequency, and q value. In this work, the relationship between ion trapping waveform voltage and frequency at preselected q value, the relationship between waveform frequency and the q value at certain ion trapping voltage for optimum CID efficiency were investigated. Experiment results showed that the max CID efficiency of precursor reserpine ions can be obtained at different trapping waveform voltage and frequency when q and β are different. Based on systematic experimental analysis, the optimum experimental conditions for high CID efficiency can be calculated at any selected β or q. By using digital ion trap technology, the CID process and efficient fragmentation of parent ions can be realized by simply changing the trapping waveform amplitude, frequency, and the β values in the digital ion trap mass spectrometry. The technology and method are simple. It has potential use in ion trap mass spectrometry.

  6. Tissue Distribution of Polychlorinated Biphenyls and Organochlorine Pesticides and Potential Toxicity to Alaskan Northern Fur Seals Assessed Using PCBs Congener Specific Mode of Action Schemes

    Science.gov (United States)

    The concentrations of 145 polychlorinated biphenyl (PCB) congeners were measured using gas chromatography-ion trap mass spectrometry in 8 different tissues (blubber, brain, heart, kidney, liver, lung, muscle, and reproductive tissues) of 10 Alaskan northern fur seals. The mean concentrations of bot...

  7. Charge Exchange and Chemical Reactions with Trapped Th$^{3+}$

    CERN Document Server

    Churchill, L R; Chapman, M S

    2010-01-01

    We have measured the reaction rates of trapped, buffer gas cooled Th$^{3+}$ and various gases and have analyzed the reaction products using trapped ion mass spectrometry techniques. Ion trap lifetimes are usually limited by reactions with background molecules, and the high electron affinity of multiply charged ions such as Th$^{3+}$ make them more prone to loss. Our results show that reactions of Th$^{3+}$ with carbon dioxide, methane, and oxygen all occur near the classical Langevin rate, while reaction rates with argon, hydrogen, and nitrogen are orders of magnitude lower. Reactions of Th$^{3+}$ with oxygen and methane proceed primarily via charge exchange, while simultaneous charge exchange and chemical reaction occurs between Th$^{3+}$ and carbon dioxide. Loss rates of Th$^{3+}$ in helium are consistent with reaction with impurities in the gas. Reaction rates of Th$^{3+}$ with nitrogen and argon depend on the internal electronic configuration of the Th$^{3+}$.

  8. Lorentz-violating spinor electrodynamics and Penning traps

    Science.gov (United States)

    Ding, Yunhua; Kostelecký, V. Alan

    2016-09-01

    The prospects are explored for testing Lorentz- and C P T -violating quantum electrodynamics in experiments with Penning traps. We present the Lagrange density of Lorentz-violating spinor electrodynamics with operators of mass dimensions up to 6, and we discuss some of its properties. The theory is used to derive Lorentz- and C P T -violating perturbative shifts of the energy levels of a particle confined to a Penning trap. Observable signals are discussed for trapped electrons, positrons, protons, and antiprotons. Existing experimental measurements on anomaly frequencies are used to extract new or improved bounds on numerous coefficients for Lorentz and C P T violation, using sidereal variations of observables and comparisons between particles and antiparticles.

  9. Equation of State of Protoneutron Star with Trapped Neutrinos

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hua; JIA Huan-Yu

    2006-01-01

    The influence of trapped neutrinos on the proto-neutron star is studied in the framework of relativistic mean-field theory. The results show that trapped neutrinos increase proton fraction and make the equation of state of neutron star matter softer when neglecting hyperonic freedom, while suppress the appearance of hyperons and make the equation of state stiffer when including hyperons in the protoneutron star. The maximum mass, compared with cold neutron star which is in beta equilibrium, decreases by 0.06M☉ for non-strange protoneutron star while increases by 0.21M☉ for protoneutron star with hyperons when the relative number of trapped neutrino is 0.4.

  10. Computer analysis of sodium cold trap design and performance. [LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    McPheeters, C.C.; Raue, D.J.

    1983-11-01

    Normal steam-side corrosion of steam-generator tubes in Liquid Metal Fast Breeder Reactors (LMFBRs) results in liberation of hydrogen, and most of this hydrogen diffuses through the tubes into the heat-transfer sodium and must be removed by the purification system. Cold traps are normally used to purify sodium, and they operate by cooling the sodium to temperatures near the melting point, where soluble impurities including hydrogen and oxygen precipitate as NaH and Na/sub 2/O, respectively. A computer model was developed to simulate the processes that occur in sodium cold traps. The Model for Analyzing Sodium Cold Traps (MASCOT) simulates any desired configuration of mesh arrangements and dimensions and calculates pressure drops and flow distributions, temperature profiles, impurity concentration profiles, and impurity mass distributions.

  11. In-Trap Spectroscopy of Charge-Bred Radioactive Ions

    Science.gov (United States)

    Lennarz, A.; Grossheim, A.; Leach, K. G.; Alanssari, M.; Brunner, T.; Chaudhuri, A.; Chowdhury, U.; Crespo López-Urrutia, J. R.; Gallant, A. T.; Holl, M.; Kwiatkowski, A. A.; Lassen, J.; Macdonald, T. D.; Schultz, B. E.; Seeraji, S.; Simon, M. C.; Andreoiu, C.; Dilling, J.; Frekers, D.

    2014-08-01

    In this Letter, we introduce the concept of in-trap nuclear decay spectroscopy of highly charged radioactive ions and describe its successful application as a novel spectroscopic tool. This is demonstrated by a measurement of the decay properties of radioactive mass A=124 ions (here, In124 and Cs124) in the electron-beam ion trap of the TITAN facility at TRIUMF. By subjecting the trapped ions to an intense electron beam, the ions are charge bred to high charge states (i.e., equivalent to the removal of N-shell electrons), and an increase of storage times to the level of minutes without significant ion losses is achieved. The present technique opens the venue for precision spectroscopy of low branching ratios and is being developed in the context of measuring electron-capture branching ratios needed for determining the nuclear ground-state properties of the intermediate odd-odd nuclei in double-beta (ββ) decay.

  12. Self-Trapping of Acoustic Polaron in One Dimension

    Institute of Scientific and Technical Information of China (English)

    HOU Jun-Hua; LIANG Xi-Xia

    2007-01-01

    The ground-state energy and effective mass of an acoustic polaron in one dimension are calculated by using an electron-longitudinal-acoustic-phonon interaction Hamiltonian derived here. The self-trapping of the acoustic polaron is discussed. It is found that the critical coupling constant shifts toward weaker electron-phonon interaction with the increasing cutoff wave vector and the products of the critical coupling constant by the cutoff wave vector tend to a certain value. The self-trapping of acoustic polarons in one dimension is easier to be realized than that in three- and two-dimensional systems. The self-trapping transition of acoustic polarons is expected to be observed in the one dimensional systems of alkali halides and wide-band-gap semiconductors.

  13. Fluid trapping during capillary displacement in fractures

    Science.gov (United States)

    Yang, Zhibing; Neuweiler, Insa; Méheust, Yves; Fagerlund, Fritjof; Niemi, Auli

    2016-09-01

    The spatial distribution of fluid phases and the geometry of fluid-fluid interfaces resulting from immiscible displacement in fractures cast decisive influence on a range of macroscopic flow parameters. Most importantly, these are the relative permeabilities of the fluids as well as the macroscopic irreducible saturations. They also influence parameters for component (solute) transport, as it usually occurs through one of the fluid phase only. Here, we present a numerical investigation on the critical role of aperture variation and spatial correlation on fluid trapping and the morphology of fluid phase distributions in a geological fracture. We consider drainage in the capillary dominated regime. The correlation scale, that is, the scale over which the two facing fracture walls are matched, varies among the investigated geometries between L/256 and L (self-affine fields), L being the domain/fracture length. The aperture variability is quantified by the coefficient of variation (δ), ranging among the various geometries from 0.05 to 0.25. We use an invasion percolation based model which has been shown to properly reproduce displacement patterns observed in previous experiments. We present a quantitative analysis of the size distribution of trapped fluid clusters. We show that when the in-plane curvature is considered, the amount of trapped fluid mass first increases with increasing correlation scale Lc and then decreases as Lc further increases from some intermediate scale towards the domain length scale L. The in-plane curvature contributes to smoothening the invasion front and to dampening the entrapment of fluid clusters of a certain size range that depends on the combination of random aperture standard deviation and spatial correlation.

  14. Trap induction and trapping in eight nematode-trapping fungi (Orbiliaceae) as affected by juvenile stage of Caenorhabditis elegans.

    Science.gov (United States)

    Xie, Hongyan; Aminuzzaman, F M; Xu, Lingling; Lai, Yiling; Li, Feng; Liu, Xingzhong

    2010-06-01

    This study measured trap induction and trapping on agar disks as affected by juvenile stages (J1, J2, J3, and J4) of the nematode Caenorhabditis elegans and by species of nematode-trapping fungi. Eight species of nematode-trapping fungi belonging to the family Orbiliaceae and producing four kinds of traps were studied: adhesive network-forming Arthrobotrys oligospora, A. vermicola, and A. eudermata, constricting ring-forming Drechslerella brochopaga, and Dr. stenobrocha, adhesive column-forming Dactylellina cionopaga, and adhesive knob-forming Da. ellipsospora, and Da. drechsleri. The number of traps induced generally increased with increasing juvenile stages of C. elegans. The ability to capture the juveniles tended to be similar among isolates that produced the same kind of trap but differed among species that produced different kinds of traps. Trapping by Dr. stenobrocha and Da. cionopaga was correlated with trap number and with juvenile stage. A. oligospora and A. vermicola respectively captured more than 92 and 88% of the J1, J3, and J4 but captured a lower percentage of J2. The knob-producing isolates captured more younger than elder juveniles. Partial correlation analyses demonstrated that the trap induction of the most fungal species positively correlated with the juvenile size and motility, which was juvenile stage dependent. Overall, trap induction and trapping correlated with C. elegans juvenile stage (size and motility) in six species of trapping fungi.

  15. Design, microfabrication, and analysis of micrometer-sized cylindrical ion trap arrays

    Science.gov (United States)

    Cruz, D.; Chang, J. P.; Fico, M.; Guymon, A. J.; Austin, D. E.; Blain, M. G.

    2007-01-01

    A description of the design and microfabrication of arrays of micrometer-scale cylindrical ion traps is offered. Electrical characterization and initial ion trapping experiments with a massively parallel array of 5μm internal radius (r0) sized cylindrical ion traps (CITs) are also described. The ion trap, materials, and design are presented and shown to be critical in achieving minimal trapping potential while maintaining minimal power consumption. The ion traps, fabricated with metal electrodes, have inner radii of 1, 2, 5, and 10μm and range from 5to24μm in height. The electrical characteristics of packaged ion trap arrays were measured with a vector network analyzer. The testing focused on trapping toluene (C7H8), mass 91, 92, or 93amu, in the 5μm sized CITs. Ions were formed via electron impact ionization and were ejected by turning off the rf voltage applied to the ring electrode; a current signal was collected at this time. Optimum ionization and trapping conditions, such as a sufficient pseudopotential well and high ionization to ion loss rate ratio (as determined by simulation), proved to be difficult to establish due to the high device capacitance and the presence of exposed dielectric material in the trapping region. However, evidence was obtained suggesting the trapping of ions in 1%-15% of the traps in the array. These first tests on micrometer-scale CITs indicated the necessary materials and device design modifications for realizing ultrasmall and low power ion traps.

  16. Application of Ion Trap Mass Spectrometry on Studying Thermodynamic Stability and Equilibrium of Cycled Metal Complexes%离子阱质谱分析仪在研究气态配位化合物形成及配位平衡方面的应用

    Institute of Scientific and Technical Information of China (English)

    杨鹏翔; 徐锐锋; 赵芸; 刘顺英; 胡文浩

    2013-01-01

    本研究利用离子阱质谱仪的碰撞诱导解离技术(collision-induced dissociation)和气态离子-分子反应(ion-molecule reaction)技术研究气态配位化合物的配位键形成,解离以及再平衡过程.实验发现,气相中配位化合物在被外来能量打断配位键后,可以捕获其它分子形成新的配位化合物,从而达到新的络合稳定平衡,并提出化学气相系统中配位新平衡的建立是基于金属配合物的热力学稳定性.实验结果表明,可以通过改变离子阱质谱仪的碰撞诱导解离过程中激发时间,研究配位化合物的热力学稳定性.%A combination of collision-induced dissociation (CID) and ion-molecule (I-M) reaction was used to study the re-equilibrium procedure which occurred in an ion trap mass spectrometer when collision-induced dissociation (CID) as the constant disturbance was imparted to an isolated metal complex. The re-equilibrium in the gas phase was found to proceed through ligand loss, gain or exchange reaction with the participation of solvent molecules: methanol and water. Semi-quantitative CID measurements depending on the activation time were carried out. The comparison among the kinetic behaviors of the cycled metal complexes reveals that the chemical re-equilibrium occurred in the gas-phase system is depended on the thermodynamic stability of metal complex. The feature of CID can be used to study the stability of metal complex in ion trap mass spectrometry by controlling the activation time.

  17. Laser Desorption Ionization Quadrupole Ion Trap Time-of-Flight Mass Spectrometry of Au m Fe n +/- Clusters Generated from Gold-Iron Nanoparticles and their Giant Nanoflowers. Electrochemical and/or Plasma Assisted Synthesis

    Science.gov (United States)

    Mawale, Ravi Madhukar; Ausekar, Mayuri Vilas; Pavliňák, David; Galmiz, Oleksandr; Kubáček, Pavel; Havel, Josef

    2017-02-01

    Gold nanoparticles (NP) with average diameter 100 nm synthesized from tetrachloroauric acid solution using stainless steel as a reducing agent were found to contain iron. Applying simultaneously high frequency (HF) plasma discharge in solution during the electrochemical reduction, giant gold-iron nanoflowers with average size 1000-5000 nm were formed. Scanning electron microscopy (SEM) shows the morphology of the nanopowders produced as polygonal yet nearly spherical, whereas iron content in both products determined by energy dispersive X-ray analysis (EDX) was found to be at 2.5 at. %. Laser desorption ionization (LDI) of both nanomaterials and mass spectrometric analysis show the formation of Au m Fe n +/- ( m = 1-35; n = 1-3) clusters. Structure of few selected clusters in neutral or monocharged forms were computed by density functional theory (DFT) calculations and it was found that typical distances of an iron nucleus from adjacent gold nuclei lie in the interval 2.5 to 2.7 Å. Synthetized Au-Fe nanoparticles were found stable for at least 2 mo at room temperature (even in aqueous solution) without any stabilizing agent. Produced Au-Fe nanoparticles in combination with standard MALDI matrices enhance ionization of peptides and might find use in nanomedicine.

  18. Phase I and II metabolites of speciogynine, a diastereomer of the main Kratom alkaloid mitragynine, identified in rat and human urine by liquid chromatography coupled to low- and high-resolution linear ion trap mass spectrometry.

    Science.gov (United States)

    Philipp, Anika A; Wissenbach, Dirk K; Weber, Armin A; Zapp, Josef; Maurer, Hans H

    2010-11-01

    Mitragyna speciosa (Kratom in Thai), a Thai medical plant, is misused as herbal drug of abuse. Besides the most abundant alkaloids mitragynine (MG) and paynantheine (PAY), several other alkaloids were isolated from Kratom leaves, among them the third abundant alkaloid is speciogynine (SG), a diastereomer of MG. The aim of this present study was to identify the phase I and II metabolites of SG in rat urine after the administration of a rather high dose of the pure alkaloid and then to confirm these findings using human urine samples after Kratom use. The applied liquid chromatography coupled to low- and high-resolution mass spectrometry (LC-HRMS-MS) provided detailed information on the structure in the MS(n) mode particularly with high resolution. For the analysis of the human samples, the LC separation had to be improved markedly allowing the separation of SG and its metabolites from its diastereomer MG and its metabolites. In analogy to MG, besides SG, nine phase I and eight phase II metabolites could be identified in rat urine, but only three phase I and five phase II metabolites in human urine. These differences may be caused by the lower SG dose applied by the user of Kratom preparations. SG and its metabolites could be differentiated in the human samples from the diastereomeric MG and its metabolites comparing the different retention times determined after application of the single alkaloids to rats. In addition, some differences in MS(2) and/or MS(3) spectra of the corresponding diastereomers were observed.

  19. Vibratile Coherence and Squeezing in Two Trapped Ions

    Institute of Scientific and Technical Information of China (English)

    ZENG HaoSheng; KUANG LeMan; ZHU XiWen; GAO KeLin

    2002-01-01

    It is shown that two trapped ions interacting with laser beams resonant to the first red side-band of center-of-mass mode, in Lamb Dicke regime and under rotating wave approximation, is described by a Jaynes-Cummingsmodel. For the initial condition that the motional state of center-of-mass mode is in vacuum state and the internal stateis prepared in a coherent superposition of states, coherence and squeezing for the vibratile motion of center-of-mass modeare discussed, particularly, a "weak" coherent state and a "weak" squeezed vacuum state are obtained. Collapse andrevival are also observed in this type of initial condition.

  20. The phenomenology of trapped inflation

    CERN Document Server

    Pearce, Lauren; Sorbo, Lorenzo

    2016-01-01

    Trapped inflation is a mechanism in which particle production from the moving inflaton is the main source of friction in the inflaton equation of motion. The produced fields source inflaton perturbations, which dominate over the vacuum ones. We employ the set of equations for the inflaton zero mode and its perturbations which was developed in the original work on trapped inflation, and which we extend to second order in the perturbations. We build on this study by updating the experimental constraints, and by replacing the existing approximate solutions with more accurate ones. We obtain a different numerical value for the amplitude of the scalar power spectrum, and a parametrically different result for the bispectrum. This has implications for the allowed region of parameter space in models of trapped inflation, and for some of the phenomenological results obtained in this region. The main results in the allowed region are the following: monomial inflaton potentials, such as $V \\propto \\varphi,\\, \\varphi^2$ ...

  1. Promoter trapping in Magnaporthe grisea

    Institute of Scientific and Technical Information of China (English)

    LIU Xiao-hong; LU Jian-ping; WANG Jiao-yu; MIN Hang; LIN Fu-cheng

    2006-01-01

    Application of promoter trapping based on transformation in Magnaporthe grisea is reported in this paper. Two promoter-trapping vectors, designated as pCBGFP and pEGFPHPH, were constructed and transformed into protoplasts of M.grisea. A library of 1077 transformants resistant to hygromycin B was generated. Of which, 448 transformants were found to express eGFP gene in different structures ofM. grisea. Three transformants grew slowly, 5 transformants decreased in conidiafion and 7 transformants reduced in pathogenicity greatly among these 448 transformants. Eleven transformants were checked by genomic southern blot randomly, and 9 of which were single-copy insertions. The promoter trapping technique has been applied successfully in M. grisea and can be used as a tool for functional genomic analysis.

  2. Mass Spectrometry Instrumentation in Proteomics

    DEFF Research Database (Denmark)

    Sprenger, Richard Remko; Roepstorff, Peter

    2012-01-01

    Mass spectrometry has evolved into a crucial technology for the field of proteomics, enabling the comprehensive study of proteins in biological systems. Innovative developments have yielded flexible and versatile mass spectrometric tools, including quadrupole time-of-flight, linear ion trap...

  3. Trapping ions from a fast beam in a radio-frequency ion trap: The relaxation of the ion cloud and its resulting column density

    Science.gov (United States)

    Svendsen, Annette; Nielsen, Kristian M. E.; Pedersen, Henrik B.

    2014-06-01

    The relaxation of trapped Cl2- ions and their resulting column density in a multipole radio-frequency (RF) ion trap have been investigated after loading the trap from an initial fast-moving beam exploiting a mechanism described recently [A. Svendsen et al., Phys. Rev. A 87, 043410 (2013), 10.1103/PhysRevA.87.043410] where the injection is mediated through the exchange of energy between ions and the oscillating RF field. The temporal relaxation of the energy distribution of the trapped ion cloud was probed by observing the evolution of the resulting time-of-flight distribution of ions after extraction and fragment mass analysis in a quadrupole mass filter. The ion energy distribution was found to be essentially stationary after ˜20 ms. The resulting column density of trapped ions after relaxation was probed by two-dimensional position-resolved photodissociation of the trapped Cl2- ions. A detailed statistical analysis of the ion column density in the ring-electrode trap is given, and by comparison to the experimental data, a value of the maximum adiabaticity parameter of ηmax≃0.28 is inferred. It is further demonstrated how the present experimental system allows for time-resolved mass spectrometry by probing explicitly the populations of both parent (Cl2-) and daughter (Cl-) ions as a function of time after closing the trap and after laser irradiation. Finally, it is discussed how the setup can be used to obtain absolute photodissociation cross sections via a tomographic method without assumptions on the decay law for the trapped ions.

  4. Online spectroscopy of trapped radium isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Versolato, Oscar O.; Giri, Gouri S.; Berg, Joost van den; Hoek, Duurt Johan van der; Kruithof, Wilbert; Santra, Bodhaditya; Shidling, Praveen; Willmann, Lorenz; Wilschut, Hans W.; Jungmann, Klaus [Kernfysisch Versneller Instituut, University of Groningen (Netherlands)

    2010-07-01

    Radium ions are of particular interest for a most precise measurement of Atomic Parity Violation. From a single cold and trapped ion one expects a significantly improved measurement of the weak mixing (Weinberg) angle through a determination of the light shift in the forbidden 7{sup 2}S{sub 1/2}-6{sup 2}D{sub 3/2} transition. In preparation of such precision measurements the transitions relevant for this (7S-7P, 6D-7P) were observed and measured in the isotopes {sup 212}Ra, {sup 213}Ra and {sup 214}Ra. The isotopes were produced at the TRI{mu}P facility of KVI, when a {sup 208}Pb beam hit a solid {sup 12}C target. The Ra isotopes were stopped and re-ionized to Ra{sup +} in a Thermal Ionizer, mass separated in a Wien Filter and cooled in a gas filled Radio Frequency Quadrupole. The ions were stored as a cloud in a Paul trap, where they also interacted with laser light. All necessary wavelengths were obtained by semiconductor lasers. The setup and the measurements will be discussed.

  5. Dysprosium magneto-optical traps

    CERN Document Server

    Youn, Seo Ho; Ray, Ushnish; Lev, Benjamin L

    2010-01-01

    Magneto-optical traps (MOTs) of highly magnetic lanthanides open the door to explorations of novel phases of strongly correlated matter such as lattice supersolids and quantum liquid crystals. We recently reported the first MOTs of the five high abundance isotopes of the most magnetic atom, dysprosium. Described here are details of the experimental technique employed for repumper-free Dy MOTs containing up to half a billion atoms. Extensive characterization of the MOTs' properties---population, temperature, loading, metastable decay dynamics, trap dynamics---is provided.

  6. Feedback traps for virtual potentials

    Science.gov (United States)

    Gavrilov, Momčilo; Bechhoefer, John

    2017-03-01

    Feedback traps are tools for trapping and manipulating single charged objects, such as molecules in solution. An alternative to optical tweezers and other single-molecule techniques, they use feedback to counteract the Brownian motion of a molecule of interest. The trap first acquires information about a molecule's position and then applies an electric feedback force to move the molecule. Since electric forces are stronger than optical forces at small scales, feedback traps are the best way to trap single molecules without `touching' them (e.g. by putting them in a small box or attaching them to a tether). Feedback traps can do more than trap molecules: they can also subject a target object to forces that are calculated to be the gradient of a desired potential function U(x). If the feedback loop is fast enough, it creates a virtual potential whose dynamics will be very close to those of a particle in an actual potential U(x). But because the dynamics are entirely a result of the feedback loop-absent the feedback, there is only an object diffusing in a fluid-we are free to specify and then manipulate in time an arbitrary potential U(x,t). Here, we review recent applications of feedback traps to studies on the fundamental connections between information and thermodynamics, a topic where feedback plays an even more fundamental role. We discuss how recursive maximum-likelihood techniques allow continuous calibration, to compensate for drifts in experiments that last for days. We consider ways to estimate work and heat, using them to measure fluctuating energies to a precision of ±0.03 kT over these long experiments. Finally, we compare work and heat measurements of the costs of information erasure, the Landauer limit of kT ln 2 per bit of information erased. We argue that, when you want to know the average heat transferred to a bath in a long protocol, you should measure instead the average work and then infer the heat using the first law of thermodynamics. This

  7. Rotation sensing with trapped ions

    CERN Document Server

    Campbell, W C

    2016-01-01

    We present a protocol for using trapped ions to measure rotations via matter-wave Sagnac interferometry. The trap allows the interferometer to enclose a large area in a compact apparatus through repeated round-trips in a Sagnac geometry. We show how a uniform magnetic field can be used to close the interferometer over a large dynamic range in rotation speed and measurement bandwidth without losing contrast. Since this technique does not require the ions to be confined in the Lamb-Dicke regime, thermal states with many phonons should be sufficient for operation.

  8. Classification of jet fuels by fuzzy rule-building expert systems applied to three-way data by fast gas chromatography--fast scanning quadrupole ion trap mass spectrometry.

    Science.gov (United States)

    Sun, Xiaobo; Zimmermann, Carolyn M; Jackson, Glen P; Bunker, Christopher E; Harrington, Peter B

    2011-01-30

    A fast method that can be used to classify unknown jet fuel types or detect possible property changes in jet fuel physical properties is of paramount interest to national defense and the airline industries. While fast gas chromatography (GC) has been used with conventional mass spectrometry (MS) to study jet fuels, fast GC was combined with fast scanning MS and used to classify jet fuels into lot numbers or origin for the first time by using fuzzy rule-building expert system (FuRES) classifiers. In the process of building classifiers, the data were pretreated with and without wavelet transformation and evaluated with respect to performance. Principal component transformation was used to compress the two-way data images prior to classification. Jet fuel samples were successfully classified with 99.8 ± 0.5% accuracy for both with and without wavelet compression. Ten bootstrapped Latin partitions were used to validate the generalized prediction accuracy. Optimized partial least squares (o-PLS) regression results were used as positively biased references for comparing the FuRES prediction results. The prediction results for the jet fuel samples obtained with these two methods were compared statistically. The projected difference resolution (PDR) method was also used to evaluate the fast GC and fast MS data. Two batches of aliquots of ten new samples were prepared and run independently 4 days apart to evaluate the robustness of the method. The only change in classification parameters was the use of polynomial retention time alignment to correct for drift that occurred during the 4-day span of the two collections. FuRES achieved perfect classifications for four models of uncompressed three-way data. This fast GC/fast MS method furnishes characteristics of high speed, accuracy, and robustness. This mode of measurement may be useful as a monitoring tool to track changes in the chemical composition of fuels that may also lead to property changes.

  9. Determination of Nucleotides in Lentinus Edodes by Liquid Chromatography Electrospray Ion-Trap Mass Spectrometry%液相色谱-离子阱质谱法测定香菇中的核苷酸

    Institute of Scientific and Technical Information of China (English)

    陈天文

    2009-01-01

    In this paper, a reversed-phase high performance liquid chromatography electrospray ionization tandem mass spectrometry for the determination of nucleotide in lentinus edodes was developed. The mixtures were successfully isolated on a Zorbax C_(18)column (150×2.0mm id, 5μm), ions and fragment ions for the identification and quantification of nucleotide in lentinus edodes. The limit of detections (LOD) were 0.500,0. 050, 0.020, 0. 010μg/g respectively and r were 0.9952, 0.9967, 0.9935, 0.9987 respectively. RSDs were between 3.25%-9.45%and recoveries were between 78.2% and 115.30%. The method is rapid,sensitive and reproducible.%采用液相色谱-电喷雾串联质谱法检测香菇中核苷酸.流动相为甲醇和0.1%甲酸溶液,采用梯度洗脱程序,色谱柱为Zorbax XDB-C_(18)(150×2.0mm id,5μm),流速为0.2mL·min~(-1).以准分子离子和二级碎片离子对样品中4种核苷酸进行定性和定量,方法的检测限分别为0.500、0.050、0.020、0.010μg/g,相关系数分别为0.9952、0.9967、0.9935、0.9987,相对标准偏差范围为3.25%-9,45%,样品的回收率为78.2%-115.3%.该法快速、灵敏度高、重现性好.

  10. Simultaneous identification and detection of 16 anabolic steroid hormones in muscle using liquid chromatography coupled to quadrupole/linear ion trap mass spectrometry%液相色谱-四极杆/离子阱质谱同时确证和测定肌肉中16种同化甾体激素残留

    Institute of Scientific and Technical Information of China (English)

    张鸿伟; 蔡雪; 林黎明; 陈亮珍; 梁成珠; 鲍蕾; 汤志旭; 牛增元; 王凤美

    2012-01-01

    采用液相色谱-四极杆/离子阱质谱(LC-Q/Trap-MS)建立了肌肉中16种同化甾体激素类物质(ASs)残留的同时确证及测定方法.肌肉中的ASs采用乙腈超声辅助提取,正己烷脱脂,氨基固相萃取柱净化,CAPCELL PAKC18 MGⅢ柱(150 mm×2.0 mm,5.0μm)分离,0.1% (v/v)甲酸-乙腈溶液和0.1% (v/v)甲酸-5 mmol/L甲酸铵水溶液为流动相梯度洗脱;预设定多反应监测( sMRM)-信息依赖性采集(IDA)-增强子离子扫描(EPI)模式检测,在线EPI谱库确证,内标法定量.结果表明,16种ASs在线性范围内线性关系良好(r≥0.999);定量限(LOQ,S/N≥10)为0.029~ 0.36 μg/kg;3个添加水平(0.5、2.0和20 μg/kg)下的回收率为89.9% ~ 118%;相对标准偏差(RSD)为6.3%~16.2%.该方法准确灵敏,一次性完成16种ASs的确证和测定,可有效用于肌肉组织中ASs残留的监测分析.%A comprehensive method for simultaneous identification and detection of 16 anabolic steroid hormones (ASs, including andorgens, gestagens and their esters) in muscle samples was developed with liquid chromatography coupled to quadrupole/linear ion trap mass spectrometry (LC-Q/Trap-MS). The ASs in muscle samples were extracted with acetonitrile under ultrasonic assistance. The extract was defatted by n-hexane with liquid-liquid partitioning and followed by clean-up with NH2 solid phase extraction (SPE) cartridge. The separation of ana-lytes was carried out on a CAPCELL PAK C18 MG Ⅲ column (150 mm ×2.0 mm, 5. 0 μm) using mobile phases of 0.1 % ( v/v) formic acid in acetonitrile and 0.1% ( v/v) formic acid-5 mmol/L ammonium formate aqueous solution with gradient elution. A scheduled multiple reaction monitoring (sMRM) in positive mode as survey scan and an enhanced product ion (EPI) scan as dependent scan in an information-dependent acquisition (IDA) experiment was adopted in mass spectrometry acquisition. On-line lab-built MS/MS library and internal standards were employed for the

  11. Ion traps for precision experiments at rare-isotope-beam facilities

    Science.gov (United States)

    Kwiatkowski, Anna

    2016-09-01

    Ion traps first entered experimental nuclear physics when the ISOLTRAP team demonstrated Penning trap mass spectrometry of radionuclides. From then on, the demand for ion traps has grown at radioactive-ion-beam (RIB) facilities since beams can be tailored for the desired experiment. Ion traps have been deployed for beam preparation, from bunching (thereby allowing time coincidences) to beam purification. Isomerically pure beams needed for nuclear-structure investigations can be prepared for trap-assisted or in-trap decay spectroscopy. The latter permits studies of highly charged ions for stellar evolution, which would be impossible with traditional experimental nuclear-physics methods. Moreover, the textbook-like conditions and advanced ion manipulation - even of a single ion - permit high-precision experiments. Consequently, the most accurate and precise mass measurements are now performed in Penning traps. After a brief introduction to ion trapping, I will focus on examples which showcase the versatility and utility of the technique at RIB facilities. I will demonstrate how this atomic-physics technique has been integrated into nuclear science, accelerator physics, and chemistry. DOE.

  12. Dust traps as planetary birthsites: basics and vortex formation

    CERN Document Server

    Owen, James E

    2016-01-01

    We present a simple model for low-mass planet formation and subsequent evolution within "transition" discs. We demonstrate quantitatively that the predicted and observed structure of such discs are prime birthsites of planets. Planet formation is likely to proceed through pebble accretion, should a planetary embryo ($M\\gtrsim 10^{-4}\\,$M$_\\oplus$) form. Efficient pebble accretion is likely to be unavoidable in transition disc dust traps, as the size of the dust particles required for pebble accretion are those which are most efficiently trapped in the transition disc dust trap. Rapid pebble accretion within the dust trap gives rise, not only to low-mass planets, but to a large accretion luminosity. This accretion luminosity is sufficient to heat the disc outside the gravitational influence of the planet and makes the disc locally baroclinic, and a source of vorticity. Using numerical simulations we demonstrate that this source of vorticity can lead to the growth of a single large scale vortex in $\\sim 100$ or...

  13. Lifetime measurement of trapped staus using ATLAS

    CERN Document Server

    Sibley, Logan

    I study the creation of long-lived staus at a 14 TeV centre of mass energy in proton-proton collisions at the LHC using both the ATLAS and ACME detectors. The ATLAS overburden or underburden, or even ATLAS itself, may trap the semi-stable staus at that place where they will remain until the time at which they decay, where the stau lifetime ranges between seven days and one year. Using a novel method, one may count the number of muons and pions originating from the stau decay using the standard ATLAS cosmic ray trigger. Using an idealized detector model, I find that this method can lead to measurements of the stau lifetime and SUSY cross-section to within statistical uncertainties of 6% and 1% of their actual values, respectively.

  14. Evading the joint decision trap

    DEFF Research Database (Denmark)

    Stenbæk, Jørgen; Jensen, Mads Christian Dagnis

    2016-01-01

    is applied, including the concept of the joint-decision trap. The paper finds that the outcome was made possible by compensating the member states that were worst affected by the policy changes. A coalition of net contributors, centered on Germany and the United Kingdom, was influential regarding the overall...

  15. Optical trapping of coated microspheres

    NARCIS (Netherlands)

    Bormuth, V.; Jannasch, A.; Ander, M.; van Kats, C.M.; van Blaaderen, A.; Howard, J.; Schäffer, E.

    2008-01-01

    In an optical trap, micron-sized dielectric particles are held by a tightly focused laser beam. The optical force on the particle is composed of an attractive gradient force and a destabilizing scattering force. We hypothesized that using anti-reflection-coated microspheres would reduce scattering a

  16. Optical trapping of coated microspheres.

    Science.gov (United States)

    Bormuth, Volker; Jannasch, Anita; Ander, Marcel; van Kats, Carlos M; van Blaaderen, Alfons; Howard, Jonathon; Schäffer, Erik

    2008-09-01

    In an optical trap, micron-sized dielectric particles are held by a tightly focused laser beam. The optical force on the particle is composed of an attractive gradient force and a destabilizing scattering force. We hypothesized that using anti-reflection-coated microspheres would reduce scattering and lead to stronger trapping. We found that homogeneous silica and polystyrene microspheres had a sharp maximum trap stiffness at a diameter of around 800 nm--the trapping laser wavelength in water--and that a silica coating on a polystyrene microsphere was a substantial improvement for larger diameters. In addition, we noticed that homogeneous spheres of a correct size demonstrated anti-reflective properties. Our results quantitatively agreed with Mie scattering calculations and serve as a proof of principle. We used a DNA stretching experiment to confirm the large linear range in detection and force of the coated microspheres and performed a high-force motor protein assay. These measurements show that the surfaces of the coated microspheres are compatible with biophysical assays.

  17. Funnel traps capture a higher proportion of juvenile Great Tits Parus major than automatic traps

    Science.gov (United States)

    Senar, J.C.; Domenech, J.; Conroy, M.J.

    1999-01-01

    We compared capture rates of Great Tits at funnel traps, where several birds can be captured at once so that some decoy effect may appear, to those obtained at automatic traps, where only one bird can be trapped at a time, at trapping stations in northeastern Spain. Juvenile birds were mainly captured at funnel traps (79% of juvenile captures), whereas adult plumaged birds were captured at both types of traps (51% of captures were at the funnel traps) (test between ages, PTits had lower body condition as measured by ptilochronology (P<0.01). These birds are more easily trapped in funnel traps, which may be acting as decoy traps, and thus are vulnerable to the same kinds of biases (eg age or body condition) that have been previously documented for decoy traps.

  18. 50 CFR 697.19 - Trap limits and trap tag requirements for vessels fishing with lobster traps.

    Science.gov (United States)

    2010-10-01

    ... vessels fishing with lobster traps. 697.19 Section 697.19 Wildlife and Fisheries FISHERY CONSERVATION AND... requirements for vessels fishing with lobster traps. (a) Trap limits for vessels fishing or authorized to fish... management area designation certificate or valid limited access American lobster permit specifying one...

  19. Volatile Release From The Siberian Traps Inferred From Melt Inclusions

    Science.gov (United States)

    Black, Benjamin A.; Elkins-Tanton, Linda T.; Rowe, Michael C.; Ukstins Peate, Ingrid

    2010-05-01

    The Siberian Traps Large Igneous Province is one of the largest known continental flood volcanic provinces in the Phanerozoic. The quantification of volatile degassing is particularly important because the Siberian Traps have often been invoked as a possible trigger for the end-Permian mass extinction (e.g. Campbell et al., 1992; Wignall, 2001). Volatile degassing provides a crucial mechanism to link mafic volcanic eruption with global environmental change. Mafic flood basalt magmas are expected to have low volatile contents (similar to mid-ocean ridge basalts). However, Siberian Traps magmas were chambered in and erupted through a thick sedimentary basin and may have interacted with, and obtained volatiles from, sedimentary lithologies such as limestone, coal, and evaporite. Melt inclusions from the Siberian Traps provide insight into the potential total volatile budget throughout the evolution of the large igneous province. These droplets of trapped melt may preserve volatile species that would otherwise have degassed at the time of eruption. We present data from the analysis of more than 100 melt inclusions, including both homogenized inclusions and rare glassy inclusions with low crystallinity. Many melt inclusions from tuffs and flows near the base of the Siberian Traps sequence are substantially enriched in chlorine and fluorine compared to Deccan Traps and Laki melt inclusions (Self et al., 2008; Thordarson et al., 1996). These inclusions record chlorine concentrations up to ~1400 ppm, and fluorine concentrations up to ~5000 ppm. Olivines from the Maymechinsky suite, recognized as the last extrusive products of Siberian Traps volcanism, contain melt inclusions with maximum sulfur concentrations in the range of ~5000 ppm and substantial concentrations of chlorine. Intrusive igneous rocks from the province also display significant volatile contents. A sill from the Ust-Ilimsk region yielded plagioclase-hosted melt inclusions which contain chlorine and fluorine

  20. Furbearer Trapping Plan : Trempealeau National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Trempealeau National Wildlife Refuge Trapping Plan outlines trapping areas, species, regulations, equipment and seasons. This plan will allow harvest of a...

  1. Benton Lake National Wildlife Refuge : Trapping Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Benton Lake NWR trapping plan outlines trapping areas, species, regulations, equipment, and seasons. This plan will allow harvest of a renewable natural resource...

  2. A Portable Root-door Hog Trap

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Since the early 1960's, over 4,500 wild hogs have been relocated through Florida Game and Fresh Water Fish Commission trapping operations. The trap now used by the...

  3. Trap split with Laguerre-Gaussian beams

    CERN Document Server

    Kazemi, Seyedeh Hamideh; Mahmoud, Mohammad

    2016-01-01

    The optical trapping techniques have been extensively used in physics, biophysics, micro-chemistry, and micro-mechanics to allow trapping and manipulation of materials ranging from particles, cells, biological substances, and polymers to DNA and RNA molecules. In this Letter, we present a convenient and effective way to generate a novel phenomenon of trapping, named trap split, in a conventional four-level double-$\\Lambda$ atomic system driven by four femtosecond Laguerre-Gaussian laser pulses. We find that trap split can be always achieved when atoms are trapped by such laser pulses, as compared to Gaussian ones. This work would greatly facilitate the trapping and manipulating the particles and generation of trap split. It may also suggest the possibility of extension into new research fields, such as micro-machining and biophysics.

  4. Oxford ion-trap quantum computing project.

    Science.gov (United States)

    Lucas, D M; Donald, C J S; Home, J P; McDonnell, M J; Ramos, A; Stacey, D N; Stacey, J-P; Steane, A M; Webster, S C

    2003-07-15

    We describe recent progress in the development of an ion-trap quantum information processor. We discuss the choice of ion species and describe recent experiments on read-out for a ground-state qubit and photoionization trap loading.

  5. Optical and Magnetic Trapping of Potassium 39

    Science.gov (United States)

    Ensher, Jason; Cornell, Eric; Cataliotti, Francesco; Fort, Chiara; Marin, Francesco; Prevedelli, Marco; Inguscio, Massimo; Ricci, Leonardo; Tino, Guglielmo

    1998-05-01

    We present measurments of optical trapping and cooling and magnetic trapping of ^39K in a double-MOT apparatus. (Optics Lett. 21, 290(1996)) We have measured light-assisted collisional loss rates from our second MOT over a range of trap light intensities. At an intensity of 10 mW/cm^2 we find a loss rate parameter β of 2 x 10-11 cc/s. β increases with trap light intensity and is consistent with the values measured by Williamson and Walker (JOSA B 12, 1393 (1995)). We also present studies of the temperature of atoms in a MOT of ^39K. Under certain conditions of repump light intensity and trap light detuning we measure temperatures nearly as low as the Doppler Limit. Finally, we report on prelimiary results of magnetic trapping in which we have trapped several 10^7 atoms in a quadrupole magnetic trap.

  6. Electrostatic model of semiconductor nanoparticles trapped in polymer electrolytes

    Indian Academy of Sciences (India)

    Divya Singh; Pramod K Singh; Nitin A Jadhav; Bhaskar Bhattacharya

    2013-11-01

    A simple electrostatic model is applied to study the solvation energy and localization energy to inorganic semiconductor nanocrystallites trapped in polymer and ion conducting polymer electrolytes. The effective mass approximation has been applied to the system. In the single charge configuration, the dielectric constant of the medium has been identified as the selection criteria for hosting the nanoparticles. Solvation energy has been shown to depend on the host medium and the size of the crystallite.

  7. (2,4-二甲氧基苯基)烯丙基丙二酸二乙酯异构体的GC/MS研究%Study on Diethyl [3-(2,4-Dimethoxyphenyl) Allyl] Malonate Isomers by Gas Chromatography-Mass Spectrometry

    Institute of Scientific and Technical Information of China (English)

    王敏; 彭奇

    2012-01-01

    A method applying gas chromatography-ion trap mass spectrometry (GC/MS) for the simultaneous analysis of diethyl [3-(2,4-dimethoxyphenyl)allyl]malonate isomers is described. The diethyl [3-(2,4-dimethoxyph-enyl)allyl]malonate mixture of isomers was prepared by the decarboxylative Heck reaction of 2,4-dimethoxybenzoic acid with diethyl 2-al-lylmalonate firstly, and then was analyzed by GC/MS in Electron ionization (El) and Chemical ionization (CD full-scan mode. Two components were isolated by gas chromatography" and identified as isomers from the determination of the molecular ions. Next, the isomers were analyzed by tandem mass spectrometry (MS/MS) mode. Through the analysis of different cleavage fragments of the isomers in MS/MS mode, mass spectrometric fragmentation pathways of the isomers were discussed. The structures of two isomers were determined on the base of different mass characteristic fragmentation pathways. This new meth- od of identifying isomers is a time-saving, economical and effective method, which could provide reference for analysis and identification of this kind of compounds.%为了研究钯催化的2,4-二甲氧基苯甲酸与烯丙基丙二酸二乙酯的脱羧Heck反应的产物结构,建立了(2,4-二甲氧基苯基)烯丙基丙二酸二乙酯同分异构体的分离与鉴定的气相色谱-离子阱质谱方法.首先通过脱羧Heek反应制得(2,4-二甲氧基苯基)烯丙基丙二酸二乙酯异构体混合物,然后利用GC/MS联用技术对混合物进行分析,得到各组分的EI和CI全扫描模式质谱信息.通过对照各组分的分子离子峰确定互为异构体的组分,再对异构体组分采用MS/MS模式获取各自的裂解碎片.通过分析异构体的不同的裂解碎片,讨论质谱裂解方式,从而确定异构体的结构.该方法省时、经济、高效,可为此类化合物的分析与鉴别提供参考.

  8. Extending the dynamic range of the ion trap by differential mobility filtration.

    Science.gov (United States)

    Hall, Adam B; Coy, Stephen L; Kafle, Amol; Glick, James; Nazarov, Erkinjon; Vouros, Paul

    2013-09-01

    A miniature, planar, differential ion mobility spectrometer (DMS) was interfaced to an LCQ classic ion trap to conduct selective ion filtration prior to mass analysis in order to extend the dynamic range of the trap. Space charge effects are known to limit the functional ion storage capacity of ion trap mass analyzers and this, in turn, can affect the quality of the mass spectral data generated. This problem is further exacerbated in the analysis of mixtures where the indiscriminate introduction of matrix ions results in premature trap saturation with non-targeted species, thereby reducing the number of parent ions that may be used to conduct MS/MS experiments for quantitation or other diagnostic studies. We show that conducting differential mobility-based separations prior to mass analysis allows the isolation of targeted analytes from electrosprayed mixtures preventing the indiscriminate introduction of matrix ions and premature trap saturation with analytically unrelated species. Coupling these two analytical techniques is shown to enhance the detection of a targeted drug metabolite from a biological matrix. In its capacity as a selective ion filter, the DMS can improve the analytical performance of analyzers such as quadrupole (3D or linear) and ion cyclotron resonance (FT-ICR) ion traps that depend on ion accumulation.

  9. Extending the Dynamic Range of the Ion Trap by Differential Mobility Filtration

    Science.gov (United States)

    Hall, Adam B.; Coy, Stephen L.; Kafle, Amol; Glick, James; Nazarov, Erkinjon

    2013-01-01

    A miniature, planar, differential ion mobility spectrometer (DMS) was interfaced to an LCQ classic ion trap to conduct selective ion filtration prior to mass analysis in order to extend the dynamic range of the trap. Space charge effects are known to limit the functional ion storage capacity of ion trap mass analyzers and this, in turn, can affect the quality of the mass spectral data generated. This problem is further exacerbated in the analysis of mixtures where the indiscriminate introduction of matrix ions results in premature trap saturation with non-targeted species, thereby reducing the number of parent ions that may be used to conduct MS/MS experiments for quantitation or other diagnostic studies. We show that conducting differential mobility-based separations prior to mass analysis allows the isolation of targeted analytes from electrosprayed mixtures preventing the indiscriminate introduction of matrix ions and premature trap saturation with analytically unrelated species. Coupling these two analytical techniques is shown to enhance the detection of a targeted drug metabolite from a biological matrix. In its capacity as a selective ion filter, the DMS can improve the analytical performance of analyzers such as quadrupole (3-D or linear) and ion cyclotron resonance (FT-ICR) ion traps that depend on ion accumulation. PMID:23797861

  10. Dynamic array of dark optical traps

    DEFF Research Database (Denmark)

    Daria, V.R.; Rodrigo, P.J.; Glückstad, J.

    2004-01-01

    A dynamic array of dark optical traps is generated for simultaneous trapping and arbitrary manipulation of multiple low-index microstructures. The dynamic intensity patterns forming the dark optical trap arrays are generated using a nearly loss-less phase-to-intensity conversion of a phase-encode...... optical traps for simultaneous manipulation of hollow "air-filled" glass microspheres suspended in an aqueous medium. (C) 2004 American Institute of Physics....

  11. A grooved planar ion trap design for scalable quantum information processing

    Institute of Scientific and Technical Information of China (English)

    Ji Wei-Bang; Wan Jin-Yin; Cheng Hua-Dong; Liu Liang

    2012-01-01

    We describe a new electrode design for a grooved surface-electrode ion trap,which is fabricated in printed-circuitboard technology with segmented electrodes.This design allows a laser beam to get through the central groove to avoid optical access blocking and laser scattering from the ion trap surface.The confining potentials are modeled both analytically and numerically.We optimize the radio frequency (rf) electrodes and dc electrodes to achieve the maximum trap depth for a given ion height above the trap electrodes.We also compare our design with the reality ion chip MI I for practical considerations.Comparison results show that our design is superior to MI I.This ion trap design may form the basis for large scale quantum computers or parallel quadrupole mass spectrometers.

  12. Encapsulated Essential Oils as an Alternative to Insecticides in Funnel Traps.

    Science.gov (United States)

    Pascual-Villalobos, M J; López, M D; Castañé, C; Soler, A; Riudavets, J

    2015-08-01

    Pheromone-lured funnel traps are widely used for pest monitoring and mass trapping in agricultural fields and stores. DDVP vapona (dichlorvos), the insecticide of choice as a killing agent inside traps, has been banned, and research on new products is being pursued. Essential oils (EO) could be an alternative if properly formulated. To test their potential, beads of encapsulated coriander and basil EO were tested in funnel traps in stores of almonds and pet foods during 2 mo. The number of adult moth (Plodia interpunctella (Hübner) and Ephestia kuehniella Zeller) dead captures was similar with either coriander or basil EO beads and with vapona tablets while there were more insects alive in the control. These preliminary results indicate a good potential for the development of such natural products as an alternative to synthetic insecticides to include them inside funnel traps.

  13. Experimental study on dipole motion of an ion plasma confined in a linear Paul trap

    Energy Technology Data Exchange (ETDEWEB)

    Ito, K., E-mail: kzito@hiroshima-u.ac.jp; Okano, T.; Moriya, K.; Fukushima, K.; Higaki, H.; Okamoto, H. [Hiroshima University, Graduate School of Advanced Sciences of Matter (Japan)

    2015-11-15

    The compact non-neutral plasma trap systems named “S-POD” have been developed at Hiroshima University as an experimental simulator of beam dynamics. S-POD is based either on a linear Paul trap or on a Penning trap and can approximately reproduce the collective motion of a relativistic charged-particle beam observed in the center-of-mass frame. We here employ the Paul trap system to investigate the behavior of an ion plasma near a dipole resonance. A simple method is proposed to calibrate the data of secular frequency measurements by using the dipole instability condition. We also show that the transverse density profile of an ion plasma in the trap can be estimated from the time evolution of ion losses caused by the resonance.

  14. Multiphonon ionization of traps formed in hafnium oxide by electrical stress

    Energy Technology Data Exchange (ETDEWEB)

    Danilyuk, A.L.; Migas, D.B.; Danilyuk, M.A.; Borisenko, V.E. [Belorussian State University of Informatics and Radioelectronics, P. Browka 6, 220013 Minsk (Belarus); Wu, X.; Pey, K.L. [Microelectronics Center, School of EEE, Nanyang Technological University, Nanyang Avenue, Singapore 639798 (Singapore); Concurrently with Engineering Product Development Pillar, Singapore University of Technology and Design, 20 Dover Drive, Singapore 138682 (Singapore); Raghavan, N. [Microelectronics Center, School of EEE, Nanyang Technological University, Nanyang Avenue, Singapore 639798 (Singapore)

    2013-02-15

    We have investigated behavior of traps formed in hafnium oxide (HfO{sub 2}) by electrical stress and their influence on the charge carrier transport through Si/SiO{sub 2}/HfO{sub 2}/poly-Si nanostructures. The traps govern the transport process assuming a capture of charge carriers followed by their ionization via the multiphonon transition mechanism. The multiphonon transitions via the Poole-Frenkel effect or electron tunneling as well as the multiphonon tunneling ionization of neutral traps have been carefully considered for charged traps. We also provide a set of parameters including the trap concentration, ionization energy, the frequency factor, the effective mass of charge carriers, optical energy, and phonon energy in order to reproduce and reasonably fit available experimental data. (Copyright copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  15. Superdense Coding via Hot Trapped Ions

    Institute of Scientific and Technical Information of China (English)

    QIN Tao; FENG Mang; GAO Ke-Lin

    2004-01-01

    Superdense coding plays an important role in quantum information and can be performed with trapped ions. By confining the ions in a linear trap or a trap-cavity setup, we propose schemes to implement a reliable superdense coding by means of bichromatic radiation method. Experimental feasibility and reliability for achieving our schemes is discussed in detail.

  16. The Aarhus Ion Micro-Trap Project

    DEFF Research Database (Denmark)

    Miroshnychenko, Yevhen; Nielsen, Otto; Poulsen, Gregers

    and installed in an ultra high vacuum chamber, which includes an ablation oven for all-optical loading of the trap [2]. The next steps on the project are to demonstrate the operation of the micro-trap and the cooling of ions using fiber delivered light. [1] D. Grant, Development of Micro-Scale Ion traps, Master...

  17. Microchip-Based Trapped-Atom Clocks

    CERN Document Server

    Vuletic, Vladan; Schleier-Smith, Monika H

    2011-01-01

    This is a chapter of a recently published book entitled Atom Chips, edited by Jakob Reichel and Vladan Vuletic. The contents of this chapter include: Basic Principles; Atomic-Fountain versus Trapped-Atom Clocks; Optical-Transition Clocks versus Microwave Clocks; Clocks with Magnetically Trapped Atoms--Fundamental Limits and Experimental Demonstrations; Readout in Trapped-Atom Clocks; and Spin Squeezing.

  18. MIGRATION TRAPS IN DISKS AROUND SUPERMASSIVE BLACK HOLES

    Energy Technology Data Exchange (ETDEWEB)

    Bellovary, Jillian M.; Low, Mordecai-Mark Mac; McKernan, Barry; Ford, K. E. Saavik [Department of Astrophysics, American Museum of Natural History, Central Park West at 79th Street, NY 10024 (United States)

    2016-03-10

    Accretion disks around supermassive black holes (SMBHs) in active galactic nuclei (AGNs) contain stars, stellar mass black holes, and other stellar remnants, which perturb the disk gas gravitationally. The resulting density perturbations exert torques on the embedded masses causing them to migrate through the disk in a manner analogous to planets in protoplanetary disks. We determine the strength and direction of these torques using an empirical analytic description dependent on local disk gradients, applied to two different analytic, steady-state disk models of SMBH accretion disks. We find that there are radii in such disks where the gas torque changes sign, trapping migrating objects. Our analysis shows that major migration traps generally occur where the disk surface density gradient changes sign from positive to negative, around 20–300R{sub g}, where R{sub g} = 2GM/c{sup 2} is the Schwarzschild radius. At these traps, massive objects in the AGN disk can accumulate, collide, scatter, and accrete. Intermediate mass black hole formation is likely in these disk locations, which may lead to preferential gap and cavity creation at these radii. Our model thus has significant implications for SMBH growth as well as gravitational wave source populations.

  19. Trapping Methylglyoxal by Genistein and Its Metabolites in Mice.

    Science.gov (United States)

    Wang, Pei; Chen, Huadong; Sang, Shengmin

    2016-03-21

    Increasing evidence supports dicarbonyl stress such as methylglyoxal (MGO) as one of the major pathogenic links between hyperglycemia and diabetic complications. In vitro studies have shown that dietary flavonoids can inhibit the formation of advanced glycation end products (AGEs) by trapping MGO. However, whether flavonoids can trap MGO in vivo and whether biotransformation limits the trapping capacity of flavonoids remain virtually unknown. In this study, we investigated whether genistein (GEN), the major soy isoflavone, could trap MGO in mice by promoting the formation of MGO adducts of GEN and its metabolites. Two different mouse studies were conducted. In the acute study, a single dose of MGO and GEN were administered to mice via oral gavage. In the chronic study, MGO was given to mice in drinking water for 1 month and then GEN was given to mice for 4 consecutive days via oral gavage. Two mono-MGO adducts of GEN and six mono-MGO adducts of GEN phase I and microbial metabolites were identified in mouse urine samples from these studies using liquid chromatography/electrospray ionization tandem mass spectrometry. The structures of these MGO adducts were confirmed by analyzing their MS(n) (n = 1-4) spectra as well as by comparing them with the tandem mass spectra of authentic standards. All of the MGO adducts presented in their phase II conjugated forms in mouse urine samples in the acute and chronic studies. To our knowledge, this is the first in vivo evidence to demonstrate the trapping efficacy of GEN in mice and to show that the metabolites of GEN remain bioactive.

  20. Scalar Trapping and Saxion Cosmology

    CERN Document Server

    Moroi, Takeo; Nakayama, Kazunori; Takimoto, Masahiro

    2013-01-01

    We study in detail the dynamics of a scalar field in thermal bath with symmetry breaking potential. In particular, we focus on the process of trapping of a scalar field at an enhanced symmetry point through the thermal/non-thermal particle production, taking into account the interactions of produced particles with the standard model particles. As an explicit example, we revisit the saxion dynamics with an initial amplitude much larger than the Peccei-Quinn scale and show that the saxion trapping phenomenon happens for the most cases and it often leads to thermal inflation. We also study the saxion dynamics after thermal inflation, and it is shown that thermal dissipation effect on the saxion can relax the axion overproduction problem from the saxion decay.