AVS 46th International Symposium
    Surface Science Division Wednesday Sessions
       Session SS-WeP

Paper SS-WeP36
An Ultra High Vacuum Compatible Matrix Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometer

Wednesday, October 27, 1999, 5:30 pm, Room 4C

Session: Poster Session
Presenter: T.L. Porter, Northern Arizona University
Authors: T.L. Porter, Northern Arizona University
S. Hermann, Northern Arizona University
Correspondent: Click to Email
The emerging technique of matrix assisted laser desorption/ionization (MALDI) time-of-flight mass spectrometry allows for the mass determination of surface bound polymeric materials that suffer from fragmentation effects using conventional MS techniques. Using MALDI, the sample to be analyzed is combined with a strong UV absorbing "matrix", such as 3-hydroxypicolinic acid or 2,5-dihydroxybenzoic acid. Short UV laser pulses desorb the matrix plus sample material from the topmost sample surface, while simultaneously gently ionizing the sample material. The ionized species are then injected into a time-of-flight analyzer for mass determination. The gentle ionization process allows polymers and bio-materials on surfaces that would normally suffer from fragmentation effects to be detected intact. In this paper, we describe an ultra-high-vacuum MALDI instrument that has been constructed from primarily off-the-shelf components at minimal cost. This instrument may be used to detect the presence of pico-mole amounts of material with atomic weights from a few hundred to over one hundred thousand.