Enhanced analysis of poly(ethylene glycols) and peptides using thermospray mass spectrometry

A series of polyethylene glycol) (PEG) and polypropylene glycol) (PPG) samples ranging in molecular weights from 400 to 100 000 Da were characterized by time-of-flight secondary ion mass spectrometry. Molecular weight values from the oligomer distributions in the spectra were determined and compared to those obtained by conventional methods. The fragmentation patterns of the polyglycols were examined and can be explained by mechanisms involving simple chain scissions.

Section: Resultsmentioning

confidence: 99%

Investigation of Molecular Weight and Terminal Group Effects on the Time-of-Flight Secondary Ion Mass Spectra of Polyglycols

Hittle¹,

Altland²,

Proctor³

et al. 1994

“…However, due to the high pressures within the thermospray ion source, the effect the repeller has on gas-phase ion trajectories, and hence ion-extraction efficiency, is not well-defined. Studies of polyethylene glycols) and peptides show enhancements of molecular ion abundances that appears to be related to increased ion extraction efficiency (18). Observed Results.…”

Section: Methodsmentioning

confidence: 90%

Enhanced analysis of sulfonated azo dyes using liquid chromatography/thermospray mass spectrometry

McLean¹,

Freas²

1989

Self Cite

Modifications to a thermospray vaporizer probe and ion source have been made that enhance ion evaporation resulting in increased sample ion current. These modifications include restricting the thermospray vaporizer exit orifice and the addition of a needle-tip repeller electrode to the thermospray ion source. The interaction and effect of probe-tip size, repeller voltage, and flow rate on sulfonated azo dye detection are reported. An increase in signal response for sulfonated azo dyes was observed. An efficient chromatographic separation procedure for sulfonated azo dyes, which is compatible with thermospray mass spectrometric detection, is also presented. Five disulfonated azo dyes were separated and detected by using selected ion monitoring. Mass spectra of disulfonated dyes show a number of molecular ions and adduct ions that provide unequivocal molecular weight information.

“…Mass spectrometric detection has been shown to provide an extra dimension of information (mass-to-charge ratio) that is invaluable for identifying the eluting components. The most commonly used interfaces for on-line liquid chromatography-mass spectrometry (LC-MS) are thermospray (9,10) and continuous-flow fast atom bombardment (flow-FAB) (11)(12)(13). Thermospray ionization is useful for peptides as large as 2000 Da and in quantities as small as 100 pmol.…”

Section: Introductionmentioning

confidence: 99%

Characterization of the tryptic map of recombinant DNA derived tissue plasminogen activator by high-performance liquid chromatography-electrospray ionization mass spectrometry

Ling¹,

Guzzetta²,

Canova-Davis³

et al. 1991

126

A detailed tryptic map is presented for recombinant human tissue plasminogen activator (rt-PA). Electrospray ionization mass spectrometry is utilized as an on-line HPLC detector for tryptic mapping of this glycoprotein. The additional dimension provided by mass spectrometry gives considerably more detail about the complex tryptic map and significantly enhances the high-resolution chromatographic separation by distinguishing by mass any coeluting components. Through this improvement, the proline isomers of a tryptic peptide were observed eluting over a broad range of retention times. The glycopeptides of rt-PA are observed as well as any corresponding nonglycosylated peptides. In addition, the carbohydrate heterogeneity is readily observed, allowing analysis of the carbohydrate composition. The characteristic diagonal patterns formed by glycopeptides in a contour plot of the data allow rapid recognition of the glycopeptides.