hplc ms and tandem mass spectrometry

... instruments are also used to perform tandem mass spectrometry in space (Hoffmann and Stroobant 2007) Tandem Mass Spectrometry –– Applications and Principles Higher order MSn spectra can be acquired by ... reaction enthalpies, proton and ion affinities, gas-phase acidities, and so on 4 Tandem Mass Spectrometry –– Applications and Principles Mass spectrometry is extremely versatile and several areas of ... Tandem Mass Spectrometry of Tagged and Permethylated Polysaccharides 285 Wen-Bin Yang Part Metabolite Identification and Quantification 307 Chapter 14 Metabolomics Research with Tandem Mass Spectrometry...

Ngày tải lên: 31/03/2014, 19:20

... and 30% solvent B (70:30, v/v) being solvent A and solvent B described in Methods Mass spectrometry A Sciex API 3000 tandem MS system was used for MS- MS detection with an electrospray ion source ... internal standard and b) without internal standard Figure the corresponded product the deuterated standards with Standard chromatogram of ion scans Standard chromatogram of the deuterated standards ... pro analysi) and ammonium acetate p.a was purchased from Merck (Darmstadt, Germany) Bi-distilled water was used for HPLC mobile phase mixture Standard preparation and internal standardization...

Ngày tải lên: 20/06/2014, 00:20

... time of flight mass spectrometry; MS/ MS: tandem mass spectrometry; MW: molecular weight; NCBI: National Center for Biotechnology Information; PCR: polymerase chain reaction; RP -HPLC: reverse phase-high ... experiments and assembled the “SuperWheat” and “subset” databases FMD fractionated wheat flour proteins used in MS/ MS analyses and contributed to experimental design All authors analyzed MS/ MS data and ... S, Lafiandra D: Characterization of B- and C-type low molecular weight glutenin subunits by electrospray ionization mass spectrometry and matrix-assisted laser desorption/ionization mass spectrometry...

Ngày tải lên: 12/08/2014, 03:21

... spectra data generated by mass spectrometry (MS) or tandem mass spectrometry (MS/ MS) The advance in tandem mass spectrometry (MS/ MS) technology has made highthroughput mass spectra generation possible ... peptide and PTM identification using tandem mass spectrometry The main concern for algorithms in peptide identification is achieving fast and accurate peptide identification by mass spectrometry ... peptide identification by tandem mass spectrometry, the input includes the mass spectrum S, the set of possible ion types ∆ and the parent mass M (and for database search algorithms, a database of peptides)...

Ngày tải lên: 12/09/2015, 08:18

... Achiral LC -MS/ MS analysis………………………………………26 2.2.5 Isolation of metabolites by preparative HPLC and MS/ MS /MS 29 2.2.6 Chiral LC -MS/ MS analysis………………………………………29 2.2.7 Metabolite synthesis and purification……………………………30 ... ultra performance liquid chromatography UFLC ultra fast liquid chromatography MS mass spectrometry MS/ MS tandem mass spectrometry ESI electrospray ionization QTRAP hybrid triple quadrupole linear ... chromatography coupled with mass spectrometry (GC -MS) , liquid chromatography (LC) coupled with ultraviolet (UV), fluorescence, radioactivity or tandem mass spectrometry (MS/ MS) Among these technologies,...

Ngày tải lên: 14/09/2015, 14:08

... through a 0.22 ␮m nylon membrane prior to LC -MS/ MS analysis 2.3 Instrumentation LC coupled with electrospray ionization tandem mass spectrometry (ESI -MS/ MS) was used for screening The LC system was ... This suggested that the HPLCMS /MS method is appropriate for the screening of illegal dyes in foods Conclusion In summary, by combining SPE cleanup and HPLC- MS/ MS, an accurate and highly sensitive ... degasser, autosampler and thermostatic column compartment The tandem mass spectrometer was an API 5000 triple quadrupole from Applied Biosystems (Darmstadt, Germany) Applied Biosystems Analyst software...

Ngày tải lên: 25/08/2016, 22:30

... to real-time monitoring, tandem mass spectrometry (MSn) helps to identify unknown species, validate proposed intermediates and further understand the reaction mechanisms To demonstrate this, an ... reactions using EESI -MS Figure Mass spectra of the Michael addition reaction recorded at 20, 60 and 300 min, respectively Inserts: molecular structures of PEA, PEAP and CPEAP 2995 (PAs) and remain undetectable, ... (99%) from Acros (Geel, Belgium) and ethanol (HPLC) from Merck (Darmstadt, Germany) Dichloromethane was purchased from J.T Baker (Deventer, The Netherlands) RESULTS AND DISCUSSION EXPERIMENTAL In...

Ngày tải lên: 14/02/2014, 08:20

... which are referred to as quasi -MS/ MS /MS ions The comparison of the spectra of quasi -MS/ MS and of quasi -MS/ MS /MS may yield the quasi-third order precursor ions The quasi -MS4 spectra may be obtained ... spectrometry; LC-ESI /MS: liquid chromatography-electrospray mass spectrometry; HPLC- DAD: highperformance liquid chromatography-diode array detection; MS/ MS: tandem mass spectrometry; RDA: retroDiels-Alder; ... hesperetin and neohesperetin were 5.5, 8.0, 9.3 and 10.3 minutes respectively which underwent CID = 30 v to obtain quasi -MS/ MS /MS spectra We found an unusual phenomenon in the quasiMS /MS/ MS spectra...

Ngày tải lên: 13/08/2014, 15:21

... analogues in natural and cultured Cordyceps by pressurized liquid extraction and high performance liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC- ESI -MS/ MS) Anal Chim Acta ... coupled with diode array detector and mass spectrometry (HPLCDAD-ESI -MS) and to assess the quality of two commercial mycelial AC products Methods Plant Powdered mycelium and an intact fruiting body ... filtered, dried, and reconstituted into ml of methanol and water (85:15) The reconstituted solution was then filtered before HPLC injection Results and discussion Nucleosides and nucleobases as...

Ngày tải lên: 13/08/2014, 15:21

... and 200 lL of 100% acetonitrile The solutions were combined and concentrated in a SpeedVac iTRAQ labeling and LC-ESI MS/ MS analysis To label peptides with the iTRAQ reagent (Applied Biosystems, ... UK) Peak lists were generated and processed using mascot distiller v2.1.1.0 (Matrix Science) Search parameters for peptide and MS ⁄ MS mass tolerance were ± 0.1 Da and ± 0.1 Da, respectively, with ... prior to MS analysis In our method, we decided to analyze the sample directly by RPLC -MS ⁄ MS three times to obtain a confident protein identification result Using the iTRAQ labeling mass spectrometry, ...

Ngày tải lên: 16/02/2014, 15:20

... 2.5, 8.0 and 11.5, and aliquots of each pH value were incubated at 37 °C, 50 °C and 70 °C, respectively From these, aliquots of lL were taken at 0, 1, 2, 4, and 24 h, and prepared for MS analysis ... production and purification of the enzyme [13] The molecular mass of each purified product, as measured by MALDI-TOF MS, was 11 947.87±2 for (Met1)-ONC (M23L) and 11 838.21±2 for rONC, which conforms well ... contribution of Met1, and Met23 substituted for Leu, Fig Comparison of the cyclization reaction as a function of temperature and pH (A), (B) and (C): (d), (s) and (.) correspond to pH 2.5, 8.0 and 11.5,...

Ngày tải lên: 19/02/2014, 12:20

... °CÆmin)1 and to 310 °C at 10 °CÆmin)1 ES -MS Negative-ion ES -MS and CID MS/ MS were carried out on a Micromass (Manchester, UK) Q-Tof mass spectrometer Nitrogen was used as desolvation and nebuliser ... optimal fragmentation and, typically, 40–43 V was used for CID of [M-H]–, and 23–27 V for [M-H]2– A scan rate of 1.5 s per scan was used for both ES -MS and CID MS/ MS experiments, and the acquired ... pattern and sequence analysis of underivatized oligosaccharides by combined MS/ MS of singly and doubly charged molecular ions in negative-ion electrospray mass spectrometry J Am Soc Mass Spectrom...

Ngày tải lên: 19/02/2014, 12:20

... (GlcNAc)4, and (D) (GlcNAc)6 The reaction was quenched by the addition of acetic acid to 10% and then applied to HPLC- ESI MS For calibration of the HPLC peaks (a and b anomers) recorded at different masses ... a Hypercarb HPLC The HPLC was operated at a particularly low temperature (10 °C) and detected by ESI MS in SIM mode with selected masses from monomer to hexamer Identification of b and a anomers ... analyzed by using HPLC- ESI MS Figure shows an HPLC- MS chromatogram of chitooligosaccharide products after h of reaction time The mono-deacetylated dimer (m ⁄ z 383), trimer (m ⁄ z 586) and tetramer...

Ngày tải lên: 20/02/2014, 01:20

... Direct organic solvent analysis demands some specific features and capabilities of the ICP -MS instrument, particularly in the sample introduction and plasma systems Details are given in the following ... chamber by self-aspiration The spray chamber and plasma torch are made of highpurity quartz and any seals in the sample introduction and drain systems are replaced with solvent resistant materials ... For quadrupole ICP -MS (ICP-QMS) the established and most effective method of reducing polyatomic interferences in high purity matrices is the use of the ShieldTorch System and cool plasma conditions...

Ngày tải lên: 05/03/2014, 21:20

... Rmsd bond lengths (A) Rmsd bond angles () Number of all atoms Number of protein atoms Number of waters Number of inhibitor atoms Baverage (A2) Protein main chain atoms Protein side chain atoms ... cyclotron resonance mass spectrometry: a primer Mass Spectrom Rev 17, 135 56 Smith RD (2000) Evolution of ESI -mass spectrometry and Fourier transform ion cyclotron resonance for proteomics and other biological ... using soft ionization mass spectrometry Int J Mass Spectrom 216, 127 54 Heck AJR & van den Heuvel RHH (2004) Investigation of intact protein complexes by mass spectrometry Mass Spectrom Rev 23,...

Ngày tải lên: 07/03/2014, 17:20

... (Asp) ) from TBDMS-Asp fragment 390 – and [2-3] of PYR (Ala) ) from TBDMS-Ala fragment 232 ) based on Eq (1) The relationship between the carbon atoms of Glu and these of OAA [2-4] and Ala [2-3] ... Modeling System (GAMS) environment (ÔGAMS Development Corporation, 1998, www.gams.com), a high-level modeling system for mathematical programming problems, and the weighted least-squares mass isotopomer ... of PEP, and thereby Phe, and these of PYR, and thereby Val, are expected to be at natural abundance Fig 8C, on the other Ó FEBS 2003 Systematic flux analysis using stable isotopes and MS (Eur...

Ngày tải lên: 08/03/2014, 08:20

... and msx-3d [12]) with a mass tolerance of p.p.m We therefore used MALDITOF-TOF and ⁄ or nanoLC-Orbitrap tandem MS to further identify peptides from this list Twenty-five mono-linked peptides and ... citrate and 0.1% formic acid) and spotted (0.5 lL) on a stainless steel MALDI target (Opti-TOF; Applied Biosystems) MALDI-TOF-TOF MS and MS ⁄ MS spectra were acquired with a MALDI-TOF ⁄ TOFÔ 4800 mass ... in 1% formic acid and stored at )20 °C until MS analysis High mass MALDI-TOF MS High -mass MALDI-TOF mass spectra of the intact protein complexes were obtained using a MALDI-TOF mass spectrometer...

Ngày tải lên: 15/03/2014, 00:20

... ATLACPL and KS1 but not onto AT1, KR1, ACP1 or TE The loading module fragment also showed two peaks, LM1 and LM2 with mass increase of 67 and 137 Da (theoretical mass increase of 70 and 140 Da, ... specificity and organization of type I PKSs The methodology is based on accessible and simple mass spectrometry equipment rather than advanced FT-ICR -MS Nevertheless, the technology can achieve mass ... Limited proteolysis and MS of modular PKSs Fig Deconvoluted mass spectra of loading didomain ATL-ACPL released from DKS by limited proteolysis (A) unliganded loading module; (B) and (C), loading...

Ngày tải lên: 16/03/2014, 18:20

... threshold 441 Present and < Mass 443 High -mass resolution 442 Base peak or >50% of Mass 198 High -mass resolution and sensitivity 443 15-24% of Mass 442 High -mass resolution and isotope ratio All ... peak Low -mass sensitivity 68

Ngày tải lên: 22/03/2014, 14:20