A New Approach to Accurate Mass Measurement by Field Desorption Peak Matching

Despite the standard ionization techniqus. EI, CI, FAB, etc., there is still a continuing analytical utility for Field Desorption (FD) for certain classes of compounds. Therefore, the method of accurate mass measurement by FD Peak Matching was investigated. Recent advances in instrument control and data acquisition/processing (post-acquisition data processing) with the engineering workstation have enabled accurate mass measurement to become a viable option for routine analysis. Molecular masses of thirteen standard compounds were measured by the FD Peak Matching to illustrate the applicability of this method. Generally, both sample and reference, PEG400 or PEG600, were loaded onto the same emitter. The possibility of using separate emitters for sample and reference was also explored. The accuracy obtained was comparable to other routine methods (e.g., EI, FAB). Six important factors which enable accurate mass measurement to be done on a routine basis were elucidated by this investigation.