Improvements in electrospray ionization source design and advances in tandem mass spectrometry.

摘要

Mass spectrometry (MS) is an analytical tool that is widely used to identify the mass-to-charge ratio and abundance of components within a sample. However, without fragmentation the only information that can be garnered from a typical mass spectrum is the mass-to-charge ratio of the intact ion. Knowing only the mass-to-charge ratio of the intact ion is typically not descriptive enough for an accurate identification. To overcome the disadvantage of limited fragmentation, the intact ion can be activated through one of a number of processes to induce dissociation. The process of inducing the dissociation of a specific ion is referred to as tandem mass spectrometry (MS/MS).;The work described in this dissertation has involved the development and modification of instrumentation for the purposes of operating a multi-sprayer nESI source and for improving the amount and quality of information from MS/MS Experiments. The mass spectrometers used for the various MS/MS experiments are linear ion trap/time-of-flight (LIT/TOF) and quadrupole Fourier transform ion cyclotron resonance (Q-FTICR) instruments. The LIT/TOF and Q-FTICR instruments used for the projects described in the subsequent chapters are commercially available mass spectrometers that were modified either to perform a unique MS/MS experiment or an established MS/MS method on an instrument for the first time. Examples of unique MS/MS experiments include the implementation of iterative accumulation multiplexing (IAM) on the Q-FTICR and the development of simultaneous electron capture dissociation, collision induced dissociation, ECD+CID, on the LIT/TOF. The LIT/TOF and Q-FTICR instruments are unique in that they represent the only mass spectrometers commercially available to-date capable of performing ECD. ECD results acquired for different analytes from both instruments will be presented. Other MS/MS experiments that will be discussed include the first demonstration of electron detachment dissociation (EDD) and activated ion (AI)-ECD in the LIT/TOF.;The work described in this dissertation demonstrates improvements in the information content of MS/MS experiments. Overall, the goal was to increase the amount of information acquired about the parent ion(s) through tandem mass spectrometry.