ELECTROSPRAY TIME-OF-FLIGHT MASS SPECTROMETRY WITH PRC

AN ELECTROSPRAY (ES) ION SOURCE WILL BE INTERFACED TO A TIME-OF-FLIGHT (TOF) MASS SPECTROMETER INCORPORATING A PSEUDO-RANDOM-CHOPPING TECHNIQUE. THE TOF MASS SPECTROMETERWILL ALLOW RAPID SCAN RATES AND HIGH-MASS ANALYSIS FOR MULTIPLE AND SINGLY CHARGED IONS DELIVERED FROM THE ES ION SOURCE. USING A PSEUDO-RANDOM-CHOPPING APPROACH FOR OSCILLATING THE ES ION BEAM ACROSS AN ORIFICE INSTEAD OF THE STANDARD PERIODIC CHOPPING PATTERN CAN INCREASE THE DUTY CYCLE POTENTIALLY BY A FACTOR OF 10. THIS INCREASED DUTY CYCLE INCREASES SENSITIVITY PROPORTIONALLY WITHOUT SACRIFICING RESOLUTION. ASSEMBLY OF THE ES-TOF INSTRUMENT AND TESTING OF THE PSEUDO-RANDOM-CHOPPING TECHNIQUE WILL BE CONDUCTED IN PHASE I. THIS INSTRUMENT WILL ALLOW VERY HIGH-MASS ANALYSIS AND ON-LINE LIQUID FEED SYSTEM DETECTION WITH EXTREMELY GOOD SENSITIVITY. WITH ES AS THE INTERFACE, THIS ES-TOF INSTRUMENT CAN BE USED AS A LC/MS OR A CZE/MS ANALYZER. MORE SENSITIVE MS/MS APPLICATIONS COULD BE ACHIEVED WITH THIS ES-TOF INSTRUMENT IN PART DUE TO THE MULTIPLE CHARGING POSSIBLE IN ES.