| Abstract: | In-beam and matrix-isolation techniques have been used in the mass spectral studies of several categories of biologically significant compounds. These include amino acids, quaternary ammonium salts, vitamins and nucleosides. Molecular ions and/or (M+H)+ions are obtained, together with useful fragmentations, all of which are valuable in structural elucidations. Spectra obtained by this version of the in-beam technique are similar but not identical with those obtained by field desorption and secondary ion mass spectrometry. Ammonium and sodium chlorides, ammonium sulfate, p-toluenesulfonic and hydrochloric acids can all be used as a room temperature matrix. The detection limits for vitamin E and 2′-deoxyguanosine have been determined as 1 ngand 5 μg, respectively. |
