Matrix-assisted laser desorptionhonization (MALDI) mass spectrometry was applied to the characterization of the protein content of wines. It has been established that this technique is applicable for this purpose even without sophisticated sample preparation. Direct structural information-presence o
Investigation of the dynamics of matrix-assisted laser desorption/ionization ion formation using an electrostatic analyzer/time-of-flight mass spectrometer
โ Scribed by Kinsel, Gary R.; Gimon-Kinsel, Mary E.; Gillig, Kent J.; Russell, David H.
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 133 KB
- Volume
- 34
- Category
- Article
- ISSN
- 1076-5174
No coin nor oath required. For personal study only.
โฆ Synopsis
A hybrid electrostatic analyzer/time-of-flight mass spectrometer was used to examine the matrix-assisted laser desorption/ionization (MALDI) ion kinetic energy distributions for Na Y , protonated 7-hydroxy-4methylcoumarin matrix ions and protonated bradykinin under a variety of source region accelerating electric field conditions. Broad kinetic energy distributions are observed for the three targeted ions with the ions having both positive and negative kinetic energies relative to the full acceleration potential. The positive kinetic energy ions are shown to have flight times in good agreement with flight times calculated from first principles while the flight times of the negative kinetic energy ions diverge positively from the calculated values. Analysis of the flight time shifts for the negative kinetic energy ions allows an entrainment velocity of โผ550 m s -1 for the material to be calculated. A composite picture of the dynamics of MALDI ion formation is presented which combines promptly formed protonated matrix and analyte ions with ions formed/accelerated at delayed times in an expanding, constant velocity plume of laser desorbed material.
๐ SIMILAR VOLUMES
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used to structurally investigate a synthetic model of lignin, obtained by polymerization of coniferyl alcohol in the presence of horseradish peroxidase and hydrogen peroxide. In contrast to the widespread understanding
Two electrostatic mirrors, mounted symmetrically on the same optical axis facing each other, are used to increase the time-of-flight of molecular ions produced in matrix-assisted laser desorption/ionization (MALDI). The mirrors, which are used in the non-compensating mode, are located between a MALD
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) was used to study a series of synthetic cationic porphyrins as the perchlorate and bromide salts. This work presents the analytical results for the porphyrins obtained using 2,5-dihydroxybenzoic acid (DHB) and
Chemical degradation methods combined with matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) and post-source decay (PSD)-MALDI reflex TOF mass spectrometry (MS) were used to determine the sequence of a peptide branched on to a known peptide backbone. This study was applied to a
Fine metal or metal oxide powder as an alternative to conventional organic matrices in matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) has been utilized successfully for lower molecular mass analytes, poly(ethylene glycol) 200 (PEG 200) and methyl stearate.