Abstract: An in-source atmospheric pressure electron capture dissociation (AP-ECD) method and apparatus for mass spectrometric analysis of peptides and proteins. An electrified sprayer generates a multiply-charged peptide/protein ions from a sample solution, a source of electrons for negative reagents, and a flow of gas for guiding positively charged ions from the electrified sprayer to a downstream reaction region within the guide. The reaction region being at or near atmospheric pressure and substantially free of the electric field from the electrified sprayer. In another embodiment, the method uses electron transfer dissociation (ETD), in the event that anions are substituted for electrons as the negative reagents. Fragment ions exiting the reaction region are subsequently passed into a mass analyzer of a mass spectrometer for mass analysis of the ions.

Abstract: An in-source atmospheric pressure electron capture dissociation (AP-ECD) method and apparatus for mass spectrometric analysis of peptides and proteins. An electrified sprayer generates a multiply-charged peptide/protein ions from a sample solution, a source of electrons for negative reagents, and a flow of gas for guiding positively charged ions from the electrified sprayer to a downstream reaction region within the guide. The reaction region being at or near atmospheric pressure and substantially free of the electric field from the electrified sprayer. In another embodiment, the method uses electron transfer dissociation (ETD), in the event that anions are substituted for electrons as the negative reagents. Fragment ions exiting the reaction region are subsequently passed into a mass analyzer of a mass spectrometer for mass analysis of the ions.

Abstract: There is provided a method of, and apparatus for, analyzing a sample of an analyte provided as a sample solution comprising a solvent and an analyte. A dopant is provided, either separately or as the solvent of the sample solution. The sample solution is formed into a spray, for example in a nebulizer, and the solvent evaporated. The sample stream is irradiated in a region at atmospheric pressure, either in the liquid state prior to formation of a spray, or in the liquid state after formation of a droplet spray, or in the vapour state after evaporation of the sprayed droplets, to ionize the dopant. Then, subsequent collisions between the ionized dopant and the analyte, either directly or indirectly, result in ionization of the analyte. Analyte ions are passed from the atmospheric pressure ionization region into a mass analyzer for mass analysis. This technique has been found to give much enhanced ionization for some substances, as compared to atmospheric pressure chemical ionization.