High resolution field desorption mass spectrometry—I: Nucleosides and nucleotides

Abstract

Abstract The first complete high resolution (HR) field desorption (FD) mass spectra (MS) are presented and constitute a helpful tool in the structure elucidation of biologically significant compounds. This is especially relevant for the determination of the molecular weight of substances with very low volatilities which suffer from thermal decomposition when evaporated into the ion source. An additional advantage is the very small sample consumption (in the submicrogram range). Further improvements in the ion production method are the introduction of high temperature activated emitters and a specially designed micromanipulator for optimal adjustment of the field anodes. These enabled values of mass resolution between 15000 and 25000 (10% valley definition) to be achieved when vacuum evaporated Ag Br plates were used for photographic recording.