MATRIX-ASSISTED LASER-DESORPTION IONIZATION OF LOW-MOLECULAR-WEIGHT COMPOUNDS BY FOURIER-TRANSFORM LASER MICROPROBE MASS-SPECTROMETRY WITH EXTERNAL SOURCE
G. Kollensperger et al., MATRIX-ASSISTED LASER-DESORPTION IONIZATION OF LOW-MOLECULAR-WEIGHT COMPOUNDS BY FOURIER-TRANSFORM LASER MICROPROBE MASS-SPECTROMETRY WITH EXTERNAL SOURCE, Rapid communications in mass spectrometry, 10(5), 1996, pp. 538-550
Fourier transform laser microprobe mass spectrometry is used to perfor
m matrix-assisted laser desorption/ionization (MALDI) experiments on l
ow molecular weight compounds in the range up to 2 kDa. The optimal mo
lar ratio of analyte to matrix is determined. The use of fructose as c
o-matrix and the effect of laser irradiance on the mass spectra are st
udied. The typical power density in MALDI is compared to the laser onl
y mode. Specific experiments concerning the cationization of the analy
te are described. The observations are interpreted in terms of previou
s concepts about DI in laser mass spectrometry of solids.