✦ LIBER ✦

H-atom transfer following analyte photoionization in matrix-assisted laser desorption/ionization processes

✍ Scribed by P. J. Calba; J. F. Muller; M. Inouye

Publisher: John Wiley and Sons
Year: 1998
Tongue: English
Weight: 72 KB
Volume: 12
Category: Article
ISSN: 0951-4198
DOI: 10.1002/(sici)1097-0231(19981130)12:22<1727::aid-rcm366>3.0.co;2-#

No coin nor oath required. For personal study only.

✦ Synopsis

As recently shown in

Fourier transform ion cyclotron resonance mass spectrometry studies (Rapid Commun. Mass Spectrom. 11, 1602, 1997), photochromic systems can be used as molecular probe for the study of matrix-assited laser desorption ionization (MALDI) processes inducing the typical formation of the triply hydrogenated molecules [M 2H H] simultaneously with the color change. In this paper, a novel photochromic system blocked in its open form allows the proposal of a possible mechanism for protonated ions. The results suggest that H-atom transfer from a matrix molecule to an analyte plays an important role in the ionization step.

The transferring H-atom may be derived from electronically excited states of matrix and analyte molecules via the triplet states. Among several ionization processes described in the literature, we observe that H-atom transfer following analyte photoionization is a possible ionization mechanism in MALDI.

📜 SIMILAR VOLUMES

Role of photoionization and photochemist

Role of photoionization and photochemistry in ionization processes of organic molecules and relevance for matrix-assisted laser desorption lonization mass spectrometry

✍ H. Ehring; M. Karas; F. Hillenkamp 📂 Article 📅 1992 🏛 John Wiley and Sons 🌐 English ⚖ 986 KB

The ionization in ultraviolet laser desorption was investigated for a large number of small polar organic molecules which have a strong resonance absorption at the laser wavelength. In many cases, both positive-and/or negative-ion mass spectra show strong signals of ion species which deviate from th

Matrix-assisted Laser Desorption/Ionizat

Matrix-assisted Laser Desorption/Ionization Mass Spectrometry: a Valid Analytical Tool in the Dairy Industry

✍ Silvia Catinella; Costante Pinelli; Evaristo Dallaturca; Pietro Traldi 📂 Article 📅 1996 🏛 John Wiley and Sons 🌐 English ⚖ 335 KB 👁 2 views

## Matrix -assisted laser desorptionhonization mass spectrometry has been employed to analyse the protein content of milk samples obtained with different pasteurization and sterilization methods. The data obtained indicate that the technique can be employed as a valid analytical tool in the dairy

The initial ion velocity and its depende

The initial ion velocity and its dependence on matrix, analyte and preparation method in ultraviolet matrix-assisted laser desorption/ionization

✍ Glückmann, Matthias; Karas, Michael 📂 Article 📅 1999 🏛 John Wiley and Sons 🌐 English ⚖ 255 KB 👁 2 views

Since the early days of matrix-assisted laser desorption/ionization (MALDI), measurements showing that MALDI ions and neutrals have high initial velocities have led to wide acceptance of the idea that a jet of released material entrains analyte ions. The initial velocity, which could previously be d

A fast atom bombardment and matrix-assis

A fast atom bombardment and matrix-assisted laser desorption/ionization mass spectrometry study of doubly charged porphyrins

✍ M. Schäfer; H. Budzikiewicz 📂 Article 📅 2001 🏛 John Wiley and Sons 🌐 English ⚖ 203 KB

## Abstract In this mass spectrometry (MS) study of doubly charged porphyrin salts, fast atom bombardment (FAB) and matrix‐assisted laser desorption/ionization (MALDI) MS techniques are utilized to examine several unique ionic species. The predominant transformation of preformed doubly charged ions

Cationization Processes in Matrix-assist

Cationization Processes in Matrix-assisted Laser Desorption/Ionization Mass Spectrometry: Attachment of Divalent and Trivalent Metal Ions

✍ Carol K. L. Wong; T.-W. Dominic Chan 📂 Article 📅 1997 🏛 John Wiley and Sons 🌐 English ⚖ 187 KB 👁 2 views

In this paper, divalent and trivalent metal ions have been used as cationization reagents in matrix-assisted laser desorption/ionization (MALDI) experiments. Analytes studied include polyethylene glycol, polyethylene oxide dimethyl ether, cyclic polyethylene oxide and α-cyclodextrin. Independent of

The angular distribution of neutral poly

The angular distribution of neutral poly-alanine molecules produced in a matrix-assisted laser desorption/ionization process

✍ Edy Ayala; César Costa Vera; Per Håkansson 📂 Article 📅 1999 🏛 John Wiley and Sons 🌐 English ⚖ 72 KB 👁 1 views

The angular distribution of desorbed neutral and ionized polyalanine molecules, initially embedded in a matrix of 2,5-dihydroxybenzoic acid, has been measured for the first time. The target was irradiated with a pulsed ultraviolet laser beam (355 nm) incident at an angle of 26 °with respect to the t