Flow injection Thermospray® mass spectrometry for the automated analysis of potential agricultural chemicals

Abstract

Flow injection Thermospray mass spectrometry (TSP‐MS) has been developed and utilized for molecular weight and structural confirmation for thousands of potential new agricultural chemicals. Initially, it was necessary to find TSP conditions which provide an optimal compromise between providing reproducible, informative mass spectra and being sufficiently universal and rugged for a wide variety of compound types. By acquiring both positive‐ and negative‐ion spectra for each sample, the range of compounds that can be analyzed successfully is greatly expanded. The method developed is sufficiently universal that flow injection TSP‐MS now provides the required information in approximately 70% of the mass spectrometric structural confirmations performed at the Agricultural Research Division of American Cyanamid. The success in using flow injection TSP‐MS led to the development of instrumentation to fully automate these analyses. An IBM PC/AT® compatible computer is used to control sample delivery, data acquisition and data output. The PC performs the functions of both terminal and operator for a Finnigan® TSQ 46 triple quadrupole mass spectrometer and its Data General Nova® 4X data system, while simultaneously controlling a Micromeritics® 725 (Alcott®) autosampler and its Reodyne® 8126 pneumatically actuated 6‐port sampling valve. Furthermore, the need to document analyses in a manner that is consistent with Good Laboratory Practices has led to automated documentation for the instrument analysis log, as well as for the headers of the electronic data files and the printed spectral output. The new automated flow injection TSP‐MS system described here was constructed using only commercially available equipment and has notably improved efficiency by reducing the instrument time required to record spectra and by minimizing analyst intervention.

Networking Mass Spectrometer Data Systems for Improved Productivity and Electronic Archiving of Data

“…(1) to electronically archive mass spectrometry data at a central location on a high-capacity, fast-access device that allows rapid retrieval of archived data from any computer on the network, and (2) to allow access to mass spectrometry data and data processing and printing functions from remote locations without affecting simultaneous data acquisition at the instruments. It is somewhat difficult to quantify the improvements gained by networking our mass spectrometer data systems in light of considerable improvements in efficiency made recently by automating sample intro-duction and data acquisition [10]. Nevertheless, by successfully completing these links, we noted a substantial improvement in productivity through greatly increased access to all required information when and where it is needed.…”

Mass spectrometry analysis of new chemical entities for pharmaceutical discovery

“…The open‐access approach was pioneered by Hayward, Snodgrass, and Thomson (1993) and optimized by Pullen and coworkers at Pfizer Central Research (Pullen et al, 1995a,b). Initially, an automated column‐bypass thermospray MS system was used but later this was reconfigured into an ESI–MS system.…”

Determination of polycyclic aromatic hydrocarbons by high-performance liquid chromatography-particle beam-mass spectrometry

“…The percent relative standard deviations for the determination of 0.5 ng chrysene, 1.0 ng dibcnzola.hlanthracenc, 1.0 ng benzo[g,h,i]perylene, and 2.5 ng coronene were 20%, 2.5%, 13.7%, and 6%, respectively. The detection limits at signal/noise~3 were 0.2 ng for chrysene, 1.0 ng for dibenzola.hjanthra-Address reprint requests to introduction (DLI) [14], thermospray [15][16][17][18][19], electrospray [20][21][22], ion evaporation [13], nebulization into an atmospheric pressure chemical ionization (APCI) source [23-28], and particle-beam (PB) interfaces [29][30][31]. The particle-beam interface allows separation of the analytes from the HPLC eluent and delivers them to a conventional electron-impact (EO source, thus generating library-searchable EI spectra of the analytes.…”