No abstract

A new laser desorption mass spectrometer has been Interfaced to a liquid chromatograph using a moving stainless steel belt. Samples are sprayed on-line onto the belt under partial vacuum with a thermospray vaporizer. These samples are transported through a differentially pumped vacuum lock and ionized In the source of the mass spectrometer with 45 ns, 10s W/cm2 laser pulses from a Q-swltched Nd:YAG laser. Data on the performance of this new LC/LDMS are presented for several classes of nonvolatile, thermally labile blomolecules.An area of great analytical importance to organic and biomedical research is the development of mass spectrometric techniques for determination of high molecular weight (>1000 daltons), nonvolatile, thermally labile biomolecules (see reviews in ref 1-3). Some of the most successful approaches to this problem involve the use of desorption-ionization (DI) techniques where energetic beams of fission fragments, ions, atoms, or photons are used to desorb molecular ions from solid samples present in the source of a mass spectrometer. These DI techniques include plasma desorption mass spectrometry (PDMS) (4), secondary ion mass spectrometry (SIMS) (5,6), fast atom bombardment (FAB) (7, 8), and laser desorption mass spectrometry (LDMS) (9-19).