Orifice voltage

Mass spectrometry Positive ion electrospray ionization mass spectrometry (ESl-MS) analysis was performed on a PE API 2000 triple quadrupole mass spectrometer (Sciex, Toronto, Canada). Spray voltage was set to 4.8 kV, and 30 V orifice voltage was applied. Samples were dissolved in a methanol-water (1 1, v/v) mixture containing 0.1% acetic acid, and 5 pL of sample was injected with a flow rate of 100 pL/min. The instmment was used in a Qj scan mode in the range of m/z 400-1700, with a step size of 0.3 amu and a dwell time of 0.5 ms. Other chimeric peptides in this study were purified and characterized in the same or a very similar way. 

Increasing the orifice voltage, two different fragmentation patterns of trimeric species are observed. From ion at m/z 863 (A-type) two different ions at m/z 575 and 573 form, by Retro-Diels-Alder (RDA)... 

Figure 3.11 Chromatograms extracted from the TIC recorded in negative-mode of PCs and PAs dimers and trimers of a wine LC/ESI-MS analysis. Analytical conditions C18 (125 x 2 mm i.d., 3(r,m) narrow-bre column ion spray voltage —4000 V, orifice voltage —60 V. Binary solvent composed of A) aqueous 2% formic acid and B) acetonitrile/H20/formic acid (80 18 2v/v/v). Gradient program from 5% to 30% of B in 20min, 30-50% B in lOmin (flow rate 200p.L/min, flow rate in the ESI source 50p,L/min). (Reproduced from ]. Agric. Food (. hem., 1999, 47, 1023-1028, Fulcrand et al., with permission of American Chemical Society)...

Figure 2 CE-MS analysis of the O-PS (1.0 pg pF1) from Aeromonas salmonicida A449. (a) TIE (positive ion mode, m/z 100-1500) and extracted spectrum at 2.4 min, orifice voltage +30 V (b)TIE (negative ion mode, m/z 100-1500) and extracted spectrum at 2.2 min, orifice voltage -30 V (c) TIE (negative ion mode, m/z 100-1500) and extracted spectrum at 2.2 min, orifice voltage -200 V (d) TIE (positive ion mode, m/z 100-1500) and extracted spectrum at 2.4 min, orifice voltage +200 V. Reproduced from J. Li Z. Wang E. Altman, Rapid Commun. Mass Spectrom. 2005, 19,1305. Crown in the right of Canada.

Figure 3 CE-MS analysis of the whole cell lysates of Aeromonas salmonicida in the positive ion mode (a) type A, representative strain A449 (b) type B, representative strain 33659 (c) type C, representative strain N4705. Separation conditions are as follows barefused-silica(90cm x 50 im i.d., 185 imo.d.), 15 mmol I-1 ammonium acetate, pH 7.0, +15kV, 300mbar. Orifice voltage +200 V. Adopted from Z. Wang X. Liu A. Dacanay B. A. Harrison M. Fast D. J. Colquhoun ...

Figure 4 CE-MS and CE-MS/MS analysis (+ion mode) of LPS from in vivo Aeromonas salmonicida strain 80204-1 cells. Extracted mass spectrum and extracted MS/MS spectrum of precursor ion m/z 662.3 promoted using an orifice voltage of 120V. Reproduced from Z. Wang S. Larocque E. Vinogradov J.-R. Brisson A. Dacanay M. Greenwell L. L. Brown J. Li E. Altman, Eur. J. Biochem. 2004, 271, 4507. Blackwell Publishing Ltd.

MS measurements were performed on a Sciex API I Plus single quadruple mass spectrometer equipped with an electrospray ionisation source. The mass spectrometer was operated in negative or positive-ion mode. Ion spray voltage/orifice voltages were selected at - 4 KV/- 70 V and + 5 KV/+ 60 V, respectively. 

Under conventional MS experimental conditions, no ions associated with the 0-chain were detected in the spectra. When the orifice voltage of the mass spectrometer was increased to 4-400 V, the characteristic fragment ions corresponding to the composition and sequence of the biopolymer were clearly detected. In the spectrum. 

Figure 7 IS-CID-MS analysis of O-PS (1.0 pg pr ) from Salmonella riogrande 0 40. The experiments were performed using a 4000 Q-Trap mass spectrometer (Applied Biosystems/Sciex, Concord, Ontario, Canada) via a CE-MS interface. A sheath solution (isopropanol-methanol, 2 1) was delivered at a flow rate of 1 plmin The orifice voltage was set at +400 V. Separations were obtained on approximately 90 cm length of bare fused-silica capillary using 15 mmol ammonium acetate...

Detector UV 254 MS, Sciex API III triple quadrupole, lonSpray interface, ionizing voltage 5 kV, nebulizing gas air at 40 psi, orifice voltage 60 V, target gas argon 26 eV, post-column splitter to decrease flow to 20 p,L/min... 

Explain the concept of the stepped-orifice voltage-scanning technique for selective identification of glycopeptides. 

Detector UV 254 MS, Fisons Quattro II quadrupole, column effluent passed throu a splitter and 40 p.Li/min passed throu a 150 cm X 75 fjim fiised-silica capillary to the electrospray probe, nebulizing gas nitrogen at 12 L/h, drying gas nitrogen at 280 Uh, interface 60", capillary voltage 4 kV, con (orifice) voltage 30-80 V, photomultiplier 550 V,... 

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