THE DEVELOPMENT OF A DATA SYSTEM FOR A COMBINATION OF LIQUID-CHROMATOGRAPHY OR CAPILLARY ELECTROPHORESIS WITH AN ION-TRAP STORAGE REFLECTRON TIME-OF-FLIGHT MASS DETECTOR/

A data system based upon a 200 MHz transient recorder interface card i n a Pentium PC computer is demonstrated for on-line analysis of microb ore high-performance liquid chromatography (HPLC), capillary HPLC and capillary electrophoresis (CE) separations using a fast and sensitive ion-trap storage/reflectron time-of-flight mass spectrometric detector (IT-reTOFMS). Under the control of a user-written program, the system is capable of conducting the data acquisition and storage for a minim um of 30 min, at rates exceeding 10 Hz, of individual mass spectra con taining 16000 data points having 10 nsec resolution. The capability is mainly attributed to the use of a data reduction scheme in which only mass intensities higher than a preset threshold are saved as indexed flight-time/intensity pairs. This produces a typical reduction ratio o f 30:1 in data set size, yielding faster storage with smaller file siz e, and permits the complete set of mass spectra to be held in the comp uter's memory. In addition, the data system is capable of displaying, for real-time evaluation of the analysis, each individual mass spectru m and the total-ion chromatogram. Further, the selected-ion chromatogr ams of given masses and a 3-dimensional topographic map describing a s eparation process can be rapidly generated from the collected data for the unambiguous and high fidelity identification of target analytes i n a complex mixture.