Abstract: In some examples, an ion funnel-based collision cell may include an ion funnel entrance section formed by a plurality of adjacently disposed entrance members. Each entrance member of at least one pair of the adjacently disposed entrance members may include a successively larger opening to form a tapered or profiled entrance for ions entering the ion funnel-based collision cell. An insulation material may be disposed adjacent to or in contact with each entrance member of the at least one pair of the adjacently disposed entrance members to prevent, outside of each successively larger opening, flow of gas between each entrance member of the at least one pair of the adjacently disposed entrance members.

Abstract: In some examples, a multipole section-based ion funnel may include an ion funnel section formed by at least one pair of adjacently disposed members. A first member of the at least one pair of adjacently disposed members may include a pole structure. A second member of the at least one pair of adjacently disposed members may include a pole structure that is engageable with the pole structure of the first member to form a multipole structure.

Abstract: A quadrupole transmitting window applied by a quadrupole mass filter is characterized by a method that utilizes the noise band of a transmitted chemical noise ion signal. The mass filter may be utilized in a mass spectrometry (MS) system.

Abstract: An ion source may include an ionization chamber to be maintained at atmospheric-pressure. The ion source may further include a reduced-pressure chamber to be maintained at sub-atmospheric pressure, and an ion transfer device comprising an inlet in the ionization chamber and an outlet in the reduced-pressure chamber. The ion transfer device may define an ion path from the inlet to the outlet. The ion transfer device may be positioned to emit ions and neutral gas molecules from the outlet as an expanding beam comprising a low-gas density zone enveloped by a high-gas density region that includes a gas density that is higher than the low-gas density zone. The ion source may be utilized, for example, for ion mobility spectrometry (IMS), mass spectrometry (MS), and hybrid IM-MS.

Abstract: Electron capture dissociation (ECD) is performed by transmitting an electron beam through a cell along an electron beam axis, generating plasma in the cell by energizing a gas with the electron beam, and transmitting an ion beam through the interaction region along an ion beam axis to produce fragment ions. Generating the plasma forms an interaction region in the cell spaced from and not intersecting the electron beam, and including low-energy electrons effective for ECD. The ion beam axis may be at an angle to and offset from the ion beam axis, such that the electron beam does not intersect the ion beam.

Abstract: Electron capture dissociation (ECD) is performed by transmitting an electron beam through a cell along an electron beam axis, generating plasma in the cell by energizing a gas with the electron beam, and transmitting an ion beam through the interaction region along an ion beam axis to produce fragment ions. Generating the plasma forms an interaction region in the cell spaced from and not intersecting the electron beam, and including low-energy electrons effective for ECD. The ion beam axis may be at an angle to and offset from the ion beam axis, such that the electron beam does not intersect the ion beam.

Abstract: An ion transfer device for transferring ions from one chamber to another, reduced-pressure chamber includes an inlet section and a main capillary section. The inlet section has a lumen and the main capillary section has a bore communicating with the lumen. The inside diameter of the lumen is less than that of the bore. The inlet section may be removable from an installation site separately from the main capillary section. The ion transfer device may be utilized, for example, in an atmospheric-pressure interface of a mass spectrometer.

Abstract: An ion transfer device for transferring ions from one chamber to another, reduced-pressure chamber includes an inlet section and a main capillary section. The inlet section has a lumen and the main capillary section has a bore communicating with the lumen. The inside diameter of the lumen is less than that of the bore. The inlet section may be removable from an installation site separately from the main capillary section. The ion transfer device may be utilized, for example, in an atmospheric-pressure interface of a mass spectrometer.

Abstract: A field terminator includes a plurality of electrode plates positioned around a guide axis at a radial distance therefrom. The plates generate a quadrupole DC field such that a polarity on each plate is opposite to a polarity on the plates adjacent thereto. The plates may be positioned at an axial end of a quadrupole ion guide such as a mass filter. In addition to an RF field, the ion guide may generate a quadrupole DC field. The DC field of the plates may be opposite in polarity to that of the ion guide.

Abstract: An ion guide generates a first RF field of Nth order where N is an integer equal to or greater than 2, and a second RF field of 2Nth order superimposed on the first RF field. The first and second RF fields may be generated by respective first and second sets of electrodes. Another ion guide may include a converging entrance section followed by an exit section. The converging section may have a hyperbolic profile. A hyperbolic profile may be presented by electrodes having a twisted configuration relative to an ion guide axis.

Abstract: An ion guide generates a first RF field of Nth order where N is an integer equal to or greater than 2, and a second RF field of 2Nth order superimposed on the first RF field. The first and second RF fields may be generated by respective first and second sets of electrodes. Another ion guide may include a converging entrance section followed by an exit section. The converging section may have a hyperbolic profile. A hyperbolic profile may be presented by electrodes having a twisted configuration relative to an ion guide axis.

Abstract: An electron capture dissociation (ECD) apparatus includes a plasma source for generating plasma. Analyte ions are exposed to the plasma in an ECD interaction region, either inside or outside the plasma source. The apparatus may include one or more devices for refining the plasma in preparation for interaction with the analyte ions. Refining may entail removing unwanted species from the plasma, such as photons, metastable particles, neutral particles, and/or high-energy electrons unsuitable for ECD, and/or controlling a density of low-energy electrons in the plasma.

Abstract: An electron capture dissociation (ECD) apparatus includes a plasma source for generating plasma. Analyte ions are exposed to the plasma in an ECD interaction region, either inside or outside the plasma source. The apparatus may include one or more devices for refining the plasma in preparation for interaction with the analyte ions. Refining may entail removing unwanted species from the plasma, such as photons, metastable particles, neutral particles, and/or high-energy electrons unsuitable for ECD, and/or controlling a density of low-energy electrons in the plasma.

Abstract: A mass spectrum is acquired by accumulating parent ions in an ion trap, ejecting parent ions of a selected m/z ratio into a collision cell, producing fragment ions from the parent ions, and analyzing the fragment ions in a mass analyzer. The other parent ions remain stored in the ion trap, and thus the process may be repeated by mass-selectively scanning parent ions from the ion trap. In this manner, the full mass range of parent ions or any desired subset of the full mass range may be analyzed without significant ion loss or undue time expenditure. The collision cell may provide a large ion acceptance aperture and relatively smaller ion emission aperture. The collision cell may pulse ions out to the mass analyzer. The mass analyzer may be a time-of-flight analyzer. The timing of pulsing of ions out from the collision cell may be matched with the timing of pulsing of ions into the time-of-flight analyzer.

Abstract: A mass spectrum is acquired by accumulating parent ions in an ion trap, ejecting parent ions of a selected m/z ratio into a collision cell, producing fragment ions from the parent ions, and analyzing the fragment ions in a mass analyzer. The other parent ions remain stored in the ion trap, and thus the process may be repeated by mass-selectively scanning parent ions from the ion trap. In this manner, the full mass range of parent ions or any desired subset of the full mass range may be analyzed without significant ion loss or undue time expenditure. The collision cell may provide a large ion acceptance aperture and relatively smaller ion emission aperture. The collision cell may pulse ions out to the mass analyzer. The mass analyzer may be a time-of-flight analyzer. The timing of pulsing of ions out from the collision cell may be matched with the timing of pulsing of ions into the time-of-flight analyzer.

Abstract: In some embodiments, a method of optimizing operating parameters of an analytical instrument (e.g. lens voltages of a mass spectrometer) includes steps taken to minimize the method duration in the presence of substantial instrument noise and/or drift. Some methods include selecting a best point between a default instrument parameter set (vector) and a most-recent optimum parameter set; building a starting simplex at the selected best point location in parameter-space; and advancing the simplex to find an optimal parameter vector. The best simplex points are periodically re-measured, and the resulting readings are used to replace and/or average previous readings. The algorithm convergence speed may be adjusted by reducing simplex contractions gradually. The method may operate using all-integer parameter values, recognize parameter values that are out of an instrument range, and operate under the control of the instrument itself rather than an associated control computer.