Patent classifications
H01J49/0031
Method for mass spectrometry and mass spectrometer
In order to suppress a charge-up in an ion source configured to ionize a component contained in a sample gas, a mass spectrometer according to the present invention is provided with an ion source (3) including: an ionization chamber (30) having an ion ejection opening (301) and internally having a space substantially separated from an outside area; a repeller electrode (31), located within the ionization chamber, for creating an expelling electric field which acts on an ion generated within the ionization chamber to expel the ion through the ion ejection opening to the outside area; and a voltage generator (7) configured to selectively apply, to the repeller electrode, a first voltage for creating the expelling electric field and a second voltage for creating a charge-up-removing electric field, where the second voltage is a positive voltage having a larger absolute value than the first voltage.
Apparatus and methods for injecting ions into an electrostatic trap
A mass spectrometry method comprises: storing a first packet of ions within an ion storage apparatus; transferring the first ion packet into an electrostatic trap mass analyzer through a set of electrostatic lenses, wherein, during the transfer, either the lenses are operated in a first mode of operation or an injection voltage of a first pre-determined magnitude is applied to an electrode of the mass analyzer; mass analyzing the first ion packet using the mass analyzer; storing a second packet of ions within the ion storage apparatus; transferring the second ion packet into the mass analyzer through the set of lenses, wherein, during the transfer, either the lenses are operated in a second mode of operation or an injection voltage of a second pre-determined magnitude is applied to the electrode of the mass analyzer; and mass analyzing the second packet of ions using the electrostatic trap mass analyzer.
Method of operating a secondary-electron multiplier in the ion detector of a mass spectrometer
The disclosure relates to a method of operating a secondary-electron multiplier in the ion detector of a mass spectrometer so as to prolong the service life, wherein the secondary-electron multiplier is supplied with an operating voltage in such a way that an amplification of less than 10.sup.6 secondary electrons per impinging ion results, while the output current of the secondary-electron multiplier is amplified using an electronic preamplifier mounted close to the secondary-electron multiplier with such a low noise level that the current pulses of individual ions impinging on the ion detector are detected above the noise at the input of a digitizing unit. Further disclosed are the use of the methods for imaging mass spectrometric analysis of a thin tissue section or mass spectrometric high-throughput analysis/massive-parallel analysis, and a time-of-flight mass spectrometer whose control unit is programmed to execute such methods.
Systems and methods of ion population regulation in mass spectrometry
A method of performing mass spectrometry includes accumulating, over an accumulation time, ions produced from components eluting from a chromatography column and transferring the accumulated ions to a mass analyzer. During an acquisition, a mass spectrum of detected ions derived from the transferred ions is acquired. An elution profile is obtained from a series of acquired mass spectra including the acquired mass spectrum and a plurality of previously-acquired mass spectra. The elution profile includes a plurality of detection points representing intensity of the detected ions as a function of time. A current signal state of the elution profile is classified based on a subset of detection points included in the plurality of detection points. The accumulation time for a next acquisition of a mass spectrum is set based on the classified current signal state of the elution profile.
INTEGRATED HYBRID NEMS MASS SPECTROMETRY
A hybrid mass spectrometer comprising: an ion source for generating ions from a sample, a first mass spectral system comprising a nanoelectromechanical mass spectral (NEMS-MS) system, a second mass spectral system including at least one mass analyzer adapted to separate the charged particles according to their mass-to-charge ratios, and an integration zone coupling the first and second mass spectral systems, the integration zone including at least one directional device for controllably routing the ions to a selected one or both of the first and second mass spectral systems for analysis thereby. The second system can be an orbital electrostatic trap system. The ion beam can be electrically directed to one or the other system by ion optics. A chip with resonators can be used with cooling. Uses include analysis of large mass complexes found in biological systems, native single molecule analysis, and size and shape analysis.
TIP ENHANCED LASER ASSISTED SAMPLE TRANSFER FOR BIOMOLECULE MASS SPECTROMETRY
Disclosed are various embodiments for transferring molecules from a surface for mass spectrometry and other sample analysis methods, and the like. A laser is focused onto a tip of an atomic force microscope to remove and capture a quantity of molecules from the surface, so they can be transferred to a mass spectrometer or another instrument for analysis.
Method of Charge State Selection
A method of mass spectrometry or ion mobility spectrometry is disclosed in which analyte ions of a desired charge state are isolated. The method comprises: separating analytes according to their electrophoretic mobility; ionising the analytes; and mass filtering the resulting analyte ions, wherein the mass to charge ratios of the ions transmitted by a mass filter are varied as a function of the electrophoretic mobility and according to a predetermined relationship such that substantially only ions having said desired charge state are transmitted by the mass filter.
Rapid Scanning of Wide Quadrupole RF Windows While Toggling Fragmentation Energy
A sample is ionized using an ion source and the ion beam is received using a tandem mass spectrometer. An m/z range is divided into two or more precursor ion isolation windows. Two or more values for a fragmentation parameter are selected. A first value of the two or more values for the fragmentation parameter has a level that fragments a minimal amount of ions of the ion beam. The one or more additional values have increasingly aggressive levels that produce increasingly more fragmentation of the ions of the ion beam. For each precursor ion isolation window, the tandem mass spectrometer is instructed to perform a selection and fragmentation of the ion beam using the precursor ion isolation window and the first value and is instructed to perform one or more additional selections and fragmentations of the ion beam using the precursor ion isolation window and using the one or more additional values.
Device for Improved Detection of Ions in Mass Spectrometry
An electron multiplier is positioned relative to at least one dynode to direct a beam of secondary particles from the at least one dynode to a collector area of the electron multiplier and not to a channel area of the electron multiplier for a range of electron multiplier voltages applied by one or more voltage sources to the electron multiplier and for a dynode voltage applied by the one or more voltage sources to the at least one dynode. The electron multiplier includes an aperture with an entrance cone and walls of the entrance cone comprise the collector area and an apex of the entrance cone comprises the channel area. An electron multiplier voltage of the range of electron multiplier voltages is applied to the electron multiplier and the dynode voltage is applied to the at least one dynode using the one or more voltage sources.
Cold trap enhanced input into low-cost analyzer
Examples are directed toward systems and methods relating to collecting and analyzing samples. For example, a system includes a cold trap that directly collects a sample. The cold trap operates to serve as a collection filter while the system draws in a flow across the cold trap. A thermal heater, coupled to the cold trap, flash heats the cold trap to produce a released sample from the cold trap at a release concentration. An analyzer entrains the released sample at the release concentration into a sampling flow of the analyzer for analysis.