Field desorption mass spectrometry with high temperature activated emitters

Abstract The use of emitters which have been activated at high temperature in Field Ionization and Field Desorption mass spectrometry offers some important advantages over the usual emitter type activated at room‐temperature. Higher thermal stability of the microneedles is achieved and the emitters are extremely resistant to chemical attack. It becomes possible to induce a thermal fragmentation of solid compounds adsorbed on the emitter surface between room‐temperature and approximately 2000°C. The field anodes may be re‐used many times without loss of quality. The problem of mass references is solved in Field Ionization/Field Desorption‐Mass Spectrometry when high temperature emitters are used. The Field Ionization mass spectra of perfluorokerosene (PFK) and perfluorotributylamine display peaks in the mass range between m/e 50 to 800, with a resolution of up to 30000 (10% valley definition). A short description of a rapid and easy activation to produce high temperature microneedles is given. The following abbreviations are used throughout this paper:— HT High Temperature RT Room‐Temperature BAT Best Anode Temperature HR High Resolution MS Mass Spectrometry/Spectrum/Spectra EI Electron Impact FI Field Ionization CI Chemical Ionization FD Field Desorption