Abstract: Systems and methods are provided for correcting uniform detector saturation. In one method, a mass analyzer analyzes N extractions of an ion beam. A nonzero amplitude from an ADC detector subsystem is counted as one ion, producing a count of one for each ion of each sub-spectrum. The ADC amplitudes and counts of the N sub-spectra are summed, producing a spectrum that includes a summed ADC amplitude and a total count for each ion of the spectrum. A probability that the total count arises from single ions hitting the detector is calculated. For each ion of the spectrum where the probability exceeds a threshold value, an amplitude response is calculated, producing amplitude responses for ions found to be single ions hitting the detector. Amplitude responses are combined, producing a combined amplitude response. The total count is dynamically corrected using the combined amplitude response and the summed ADC amplitude.

Abstract: Systems and methods are provided for calculating and storing an average amplitude response for each peak of a mass spectrum during data acquisition. A mass analyzer is instructed to analyze N extractions of an ion beam, producing N sub-spectra. For each sub-spectrum of the N sub-spectra, a nonzero amplitude from an ADC detector subsystem is counted as one ion, producing a count of one for each ion. The ADC amplitudes and counts of the N sub-spectra are summed, producing a spectrum that includes a summed ADC amplitude and a total count for each ion. For each ion of the spectrum, an estimated ion count is calculated from a Poisson distribution of the total count of each ion for the N sub-spectra. For each ion of the spectrum, an average amplitude response is calculated by dividing the summed amplitude by the estimated ion count and stored.

Abstract: In a first location of a mass spectrometer, a plurality of ionized molecules of an ion source are selected that have mass-to-charge ratios within a mass-to-charge ratio window width. The plurality of selected ionized molecules are transmitted from a first to a second location. Reagent ions are transmitted to the second location to reduce a charge state of one or more of the plurality of selected ionized molecules. A mass analyzer is used to analyze the plurality of reduced ionized molecules and produce a mass spectrum. A compound is identified from a peak of the spectrum that has a mass-to-charge ratio less than or equal to the highest mass-to-charge ratio in the window width if the noise is multiply charged and greater than the highest mass-to-charge ratio in the window width if the noise is singly charged.

Abstract: Systems and methods are provided for correcting uniform detector saturation. In one method, a mass analyzer analyzes N extractions of an ion beam. A nonzero amplitude from an ADC detector subsystem is counted as one ion, producing a count of one for each ion of each sub-spectrum. The ADC amplitudes and counts of the N sub-spectra are summed, producing a spectrum that includes a summed ADC amplitude and a total count for each ion of the spectrum. A probability that the total count arises from single ions hitting the detector is calculated. For each ion of the spectrum where the probability exceeds a threshold value, an amplitude response is calculated, producing amplitude responses for ions found to be single ions hitting the detector. Amplitude responses are combined, producing a combined amplitude response. The total count is dynamically corrected using the combined amplitude response and the summed ADC amplitude.

Abstract: Systems and methods are provided for correcting uniform detector saturation of a mass analyzer using a calibration curve. In one method, a measured spectrum is received from a mass analyzer that includes a detector and an analog-to-digital converter (ADC) detector subsystem and that analyzes a beam of ions produced by an ion source that ionizes molecules of a sample using a processor. A total ion value of the measured spectrum is calculated by summing intensities of ions in the measured spectrum using the processor. A correction factor is determined by comparing the total ion value to a stored calibration curve that provides correction factors as a function of total ion values using the processor. Intensities of the measured spectrum are multiplied by the determined correction factor producing a corrected measured spectrum using the processor.

Abstract: Systems and related methods are disclosed herein that generally involve focusing dispersed ions using one or more DC ion funnels. In some embodiments, a DC ion funnel is provided that includes a plurality of ring-shaped electrodes, each having an aperture formed therein such that the funnel defines an interior volume extending between an ion inlet and an ion outlet. A controller applies a DC potential to each of the electrodes without applying an RF potential to any of the electrodes, such that ions entering the funnel are substantially confined within said volume. The interior volume can have any of a variety of shapes, such as cylindrical, frusto-conical, and curved frusto-conical. In addition, any of a variety of DC potentials can be applied to the plurality of electrodes.

Abstract: The present disclosure generally provides ionization methods and devices for use in mass spectrometry. In some embodiments, the ionization methods and devices employ short laser pulses (e.g., pulses having pulsewidths in a range of about 2 fs to about 1 ps) at a high intensity (e.g., an intensity in a range of about 1 TW/cm2 to about 1000 TW/cm2) to ionize an analyte an ambient pressure greater than about 10?5 Torr (e.g., an ambient pressure in a range of about 1 atmosphere to about 100 atmospheres).

Abstract: An ion source and an ion guide chamber are provided. The ion guide chamber having a gas flow, the gas flow having a longitudinal velocity and a transverse velocity. The ion guide chamber having an exit aperture and at least one ion guide. The at least one ion guide having an entrance end and an exit end with an exit cross-section wherein the exit cross-section is sized to be smaller in area than the entrance cross-section. The at least one ion guide having a plurality of elongated electrodes wherein a gap between the elongated electrodes and the shape of the elongated electrodes in the vicinity of the gap are essentially the same along the length of the at least one ion guide for confining the ions in the vicinity of the gap by a combination of the transverse velocity of the gas and the RF voltage.

Abstract: An ion source and an ion guide chamber are provided. The ion guide chamber having a gas flow, the gas flow having a longitudinal velocity and a transverse velocity. The ion guide chamber having an exit aperture and at least one ion guide. The at least one ion guide having an entrance end and an exit end with an exit cross-section wherein the exit cross-section is sized to be smaller in area than the entrance cross-section. The at least one ion guide having a plurality of elongated electrodes wherein a gap between the elongated electrodes and the shape of the elongated electrodes in the vicinity of the gap are essentially the same along the length of the at least one ion guide for confining the ions in the vicinity of the gap by a combination of the transverse velocity of the gas and the RF voltage.

Abstract: The present disclosure generally provides ionization methods and devices for use in mass spectrometry. In some embodiments, the ionization methods and devices employ short laser pulses (e.g., pulses having pulsewidths in a range of about 2 fs to about 1 ps) at a high intensity (e.g., an intensity in a range of about 1 TW/cm2 to about 1000 TW/cm2) to ionize an analyte an ambient pressure greater than about 10?5 Torr (e.g., an ambient pressure in a range of about 1 atmosphere to about 100 atmospheres).

Abstract: In a first location of a mass spectrometer, a plurality of ionized molecules of an ion source are selected that have mass-to-charge ratios within a mass-to-charge ratio window width. The plurality of selected ionized molecules are transmitted from a first to a second location. Reagent ions are transmitted to the second location to reduce a charge state of one or more of the plurality of selected ionized molecules. A mass analyzer is used to analyze the plurality of reduced ionized molecules and produce a mass spectrum. A compound is identified from a peak of the spectrum that has a mass-to-charge ratio less than or equal to the highest mass-to-charge ratio in the window width if the noise is multiply charged and greater than the highest mass-to-charge ratio in the window width if the noise is singly charged.

Abstract: Systems and related methods are disclosed herein that generally involve focusing dispersed ions using one or more DC ion funnels. In some embodiments, a DC ion funnel is provided that includes a plurality of ring-shaped electrodes, each having an aperture formed therein such that the funnel defines an interior volume extending between an ion inlet and an ion outlet. A controller applies a DC potential to each of the electrodes without applying an RF potential to any of the electrodes, such that ions entering the funnel are substantially confined within said volume. The interior volume can have any of a variety of shapes, such as cylindrical, frusto-conical, and curved frusto-conical. In addition, any of a variety of DC potentials can be applied to the plurality of electrodes.

Abstract: In a tandem mass spectrometer using a collision cell for ion fragmentation, the upper limit of the collision energy required for collision induced dissociation (CID) can be extended without reaching or going beyond the upper electrical discharge limit of the system components. The present teachings describe a method of lifting the potential energy of ions to a predetermined level sufficient for CID fragmentation while satisfying a discharge free condition. The present teaching also describes a method of lifting the potential energy of the fragment ions after CID fragmentation so that the product ions have sufficient energy for mass analysis.

Abstract: A mass spectrometer system and a method of operating a mass spectrometer are provided. An RF field is produced between the plurality of rods to radially confine the ions in the rod set. The RF field has a resolving DC component field. The resolving DC component field is varied along at least a portion of a length of the rod set to provide a DC axial force acting on the ions.

Abstract: In a tandem mass spectrometer using a collision cell for ion fragmentation, the upper limit of the collision energy required for collision induced dissociation (CID) can be extended without reaching or going beyond the upper electrical discharge limit of the system components. The present teachings describe a method of lifting the potential energy of ions to a predetermined level sufficient for CID fragmentation while satisfying a discharge free condition. The present teaching also describes a method of lifting the potential energy of the fragment ions after CID fragmentation so that the product ions have sufficient energy for mass analysis.

Abstract: An ion guide 24 for a mass spectrometer 30 including means for ejecting ions of different mass-to-charge ratios from the ion guide towards a detector or other object or device. The ejecting means causes the ions to be ejected in a desired sequence. The ions travel at different rates according to their mass-to-charge ratios, so that they arrive at a desired point in space in a desired sequence, for example in a detector 56 of a mass spectrometer at substantially the same time.

Abstract: A multi-device interface for use in mass spectrometry for interfacing one or more ion sources to one or more downstream devices. The multi-device interface comprises three or more multipole rod sets configured as either an input rod set or an output rod set depending on potentials applied to the multipole rod sets. The multipole rod sets configured as an input rod set are connectable to the one or more ion sources for receiving generated ions therefrom and sending the ions to at least one multipole rod set configured as an output multipole rod set. The output multipole rod sets are connectable to a downstream device for sending the generated ions thereto. At least two of the multipole rod sets are configured as input rod sets or at least two of the multipole rod sets are configured as output rod sets.

Abstract: There is provided a linear ion trap having an ion guide and a method of operating same. The ion guide has a first end and a second end. The method involves a) providing a first group of ions within the ion guide; b) providing a second group of ions within the ion guide, the second group of ions being opposite in polarity to the first group of ions; c) providing an RF drive voltage to the ion guide to radially confine the first group of ions and the second group of ions in the ion guide; d) providing a gas flow of an inert gas in a first axial direction away from the first end of the ion guide and toward a middle of the ion guide to repel both the first group of ions and the second group of ions from the first end of the ion guide; and, e) providing a trapping region barrier for repelling both the first group of ions and the second group of ions away from the second end of the ion guide.

Abstract: In a mass spectrometer, ions from an ion source pass through an inlet aperture into a vacuum chamber for transmitting prior to mass analysis by the mass analyzer. The configuration of the inlet aperture forms a sonic orifice or sonic nozzle and with a predetermined vacuum chamber pressure, a supersonic free jet expansion is created in the vacuum chamber that entrains the ions within the barrel shock and Mach disc. Once formed, at least one ion guide with a predetermined cross-section to essentially radially confine the supersonic free jet expansion can focus the ions for transmission through the vacuum chamber. This effectively improves the ion transmission between the ion source and the mass analyzer.

Abstract: In a mass spectrometer, ions from an ion source pass through an inlet aperture into a vacuum chamber for transmitting prior to mass analysis by the mass analyzer. The configuration of the inlet aperture forms a sonic orifice or sonic nozzle and with a predetermined vacuum chamber pressure, a supersonic free jet expansion is created in the vacuum chamber that entrains the ions within the barrel shock and Mach disc. Once formed, an ion guide with a predetermined cross-section to essentially radially confine the supersonic free jet expansion can focus the ions for transmission through the vacuum chamber. This effectively improves the ion transmission between the ion source and the mass analyzer.