Abstract: An ion mobility spectrometer is described having an ion filter in the form of at least one ion channel having a plurality of electrodes. A time-varying electric potential applied to the conductive layers allows the filler to selectively admit ion species. The electric potential has a drive and a transverse component, and in preferred embodiments each of the electrodes is involved in generating a component of both the drive and transverse fields. The device may be used without a drift gas flow. Microfabrication techniques are described for producing microscale spectrometers, as are various uses of the spectrometer.

Abstract: A reflector for a time-of-flight mass spectrometer for reflecting ionized atoms and/or molecules, with an entry opening and with an arrangement of successively arranged ring electrodes extending away from the entry opening along a longitudinal axis of the reflector is illustrated and described, as is a time-of-flight mass spectrometer. The object of providing a reflector for a time-of-flight mass spectrometer or providing such a mass spectrometer, with improved mass resolution at a high detection probability, is achieved by virtue of the fact that the ring electrode closest to the entry opening serves as a correction electrode and is at an opposite electric potential compared to the other ring electrodes, that a screening electrode is provided on the side of the entry opening facing away from the ring electrodes and that the screening electrode lies at a potential that differs from that of the ring electrodes, more preferably at earth potential.

Abstract: A patient bed drive mechanism, under control of a processor, is capable of continuously moving a patient bed through the a TOF-PET detector array having a stationary field of view (FOV) for a distance in excess of the physical extent of an axis of the array FOV. A direct memory access (DMA) rebinner card is coupled to the detector array to receive therefrom a stream of TOF-PET coincidence event data during the extent of movement of the bed. Image projection data are generated in real time from the acquired stream of TOF-PET coincidence event data via the DMA card.

Abstract: Methods for fragmenting ions in an ion trap are described.

Abstract: A trace detector is disclosed. The trace detector comprises: a desorption chamber defining a desorption region, and the desorption chamber has a housing. The housing has a sample feeding port for introducing a substance to be detected into the desorption chamber and a gas discharge port for discharging gas entraining the sample from the desorption chamber. A controller is used for controlling the trace detector in such a manner that the sample feeding port and the gas discharge port are in fluid communication with the desorption chamber during pre-concentration process of the trace detector, thereby continuously feeding and collecting the sample. With the above manner, data collecting, processing and analyzing processes may be performed by the trace detector throughout the sample feeding process and the gas pre-concentrating process.

Abstract: This disclosure relates to a method for detecting at least one analyte in a tetrachloride sample comprising titanium, tin or silicon tetrachloride; comprising, (a) adding a mixture of water and acid, typically hydrochloric acid, to the sample under conditions effective for forming an aqueous solution of the sample; (b) introducing the aqueous solution of the sample into an inductively coupled mass spectrometer having a cell selected from the group of a reactive cell and a collision cell or both and producing an analyte ion comprising an interfering species; (c) contacting the analyte ion with a gas to produce a product which is substantially free from the interfering species; and (d) detecting and measuring at least one signal from the analyte in the solution. This disclosure further relates to a method for making an aqueous titanium, tin or silicon tetrachloride sample suitable for analysis in using inductively coupled plasma mass spectroscopy.

Abstract: An ion trap instrument working at atmospheric pressure, which alleviates requirements of bulky, power consuming vacuum pumps. Traps can accumulate selected ion species, effectively concentrating the analyte of interest and allowing laser spectroscopy to be performed. This lowers the detection threshold of this instrument compared to others and increases the selectivity.

Abstract: Devices and systems for reflecting ions are provided. In general, the devices and systems include a plurality of curved lens plates adapted for connection to at least one voltage source and having a passage therein to allow the ions to pass therethrough. The plurality of curved lens plates generates electric fields having elliptic equipotential surfaces that reflect and focus the ions as they pass through the passage. Reflectron time-of-flight (RE-TOF) spectrometers are also provided that include an ion source, ion detector, and such a reflectron as described above. Mass spectrometer systems are provided that comprise an ion source that generates ions and a reflectron TOF spectrometer such as described above.

Abstract: The present invention discloses a sampling device for an ion migration spectrometer (IMS), comprising: an inner sleeve part, inside of which an inner cavity is defined, one end of the inner sleeve part is connected with an inlet of an migration pipe via an inner-layer channel, and the other end of the inner sleeve part is configured with an inner end cap having an inner opening; and an outer sleeve part, which is configured as an eccentric sleeve that is coaxial with the inner sleeve part and able to rotate with respect to the inner sleeve part, so as to form a sleeve cavity between the inner sleeve part and the outer sleeve part, wherein one end of the outer sleeve part is configured with at least one connecting opening that is selectively connected with the inner-layer channel, and the other end of the outer sleeve part is configured with an outer end cap, on which a first outer opening selectively connected with the inner opening and a second outer opening selectively connected with the sleeve cavity are c

Abstract: A mass spectrometer is disclosed comprising an ion mobility spectrometer or separator and an ion guide arranged downstream of the ion mobility spectrometer or separator. A plurality of axial potential wells are created in the ion guide so that ions received from the ion mobility spectrometer or separator become confined in separate axial potential wells. The potential wells maintain the fidelity and/or composition of ions received from the ion mobility spectrometer or separator. The potential wells are translated along the length of the ion guide.

Abstract: An ion mobility spectrometer has an inlet for an analyte substance opening into an ionization region that produces ions of the substance. Parallel grid electrodes extend laterally across the ion flow path and apply an electric field to the ions that is switchable between a relatively low magnitude alternating field that varies in magnitude over multiple periods and an asymmetric alternating field of sufficiently high magnitude to cause differential mobility effects. A collector collects the passed ions, and an indication of the nature of the analyte substance is produced from the collected ions passed during both the low and high field intervals. Also disclosed is the application of a substantially alternating field between the electrodes, which field varies between a low value and a higher value over a time exceeding that of the alternating period.

Abstract: The field of the invention is atmospheric pressure mass spectrometry (MS), and more specifically a process and apparatus which combine infrared laser ablation with electrospray ionization (ESI).

Abstract: In a charged particle detecting apparatus 100 for which an MCP is sandwiched with an IN electrode 1 and an OUT electrode and an anode electrode and a rear cover are installed therebehind, the component members in the rear of the IN electrode 1 are arranged further inside than the IN electrode 1 when viewed from an MCP incident surface, and the charged particle detecting apparatus 100 is fixed by screwing and the like to a cabinet wall surface 330 of a TOF-MS by using a flange portion provided at a part of IN electrode 1 projected further outside than the rear component members.

Abstract: A mass spectrometric analyzer and an analysis method based on the detection of ion image current are provided. The method in one embodiment includes using electrostatic reflectors or electrostatic deflectors to enable pulsed ions to move periodically for multiple times in the analyzer, forming time focusing in a portion of the ion flight region thereof, and forming an confined ion beam in space; enabling the ion beam to pass through multiple tubular image current detectors arranged in series along an axial direction of the ion beam periodically, using a low-noise electronic amplification device to detect image currents picked up by the multiple tubular detectors differentially, and using a data conversion method, such as a least square regression, to acquire a mass spectrum.

Abstract: Disclosed is a MALDI-TOF MS plate with which mass spectrometry may be performed with high reproducibility, and mass spectrum may easily be obtained even when the sample is a macromolecular substance such as a protein or nucleic acid, as well as mass spectrometry by MALDI-TOF MS using the plate. The MALDI-TOF MS plate has nanodot regions having a surface formed of a material which easily adsorbs nucleic acids and/or proteins, to which regions a test sample is attached. The mass spectrometry of a nucleic acid or protein is carried out by performing MALDI-TOF MS using this plate and using the nucleic acid or protein as a test sample.

Abstract: The invention relates to the measurement of daughter ion spectra of analyte substances that are ionized by means of matrix-assisted laser desorption. The invention shows how to record several daughter ion spectra from several parent ions per single pulse of laser light, that is per desorption event, by spatially splitting the ion beams or by temporally sequencing the spectral measurement; the various parent ions are selected one after another by switching the parent ion selector several times. Summing up corresponding individual daughter ion spectra from many pulses of laser light leads to several sum spectra being recorded practically synchronously with the same series of laser light pulses, with correspondingly reduced sample consumption and shortened data acquisition time.

Abstract: A system and method for trapping a charged particle is disclosed. A time-varying periodic multipole electric potential is generated in a trapping volume. A charged particle under the influence of the multipole electric field is confined to the trapping volume. A three electrode configuration giving rise to a 3D Paul trap and a four planar electrode configuration giving rise to a 2D Paul trap are disclosed.

Abstract: Electrodynamic on funnels confine, guide, or focus ions in gases using the Dehmelt potential of oscillatory electric field. New funnel designs operating at or close to atmospheric gas pressure are described. Effective on focusing at such pressures is enabled by fields of extreme amplitude and frequency, allowed in microscopic gaps that have much higher electrical breakdown thresholds in any gas than the macroscopic gaps of present funnels. The new microscopic-gap funnels are useful for interfacing atmospheric-pressure ionization sources to mass spectrometry (MS) and on mobility separation (IMS) stages including differential IMS or FAIMS, as well as IMS and MS stages in various configurations. In particular, “wedge” funnels comprising two planar surfaces positioned at an angle and wedge funnel traps derived therefrom can compress on beams in one dimension, producing narrow belt-shaped beams and laterally elongated cuboid packets.

Abstract: An apparatus and method for analyzing a sample containing multiple analytes that combines a separation device that separates the individual analytes by virtue of some physical and/or chemical characteristic other than the mass to charge ratio (m/z) interfaced with a mass spectrometer that detects the m/z of individual analytes. Separation is performed on the shorter timescale than signal detection with the mass spectrometer. A preferred embodiment utilizes an ion mobility spectrometer interfaced with an Orbitrap mass spectrometer.

Abstract: Analytical instruments configured to perform atmospheric pressure ionization are provided that are less than 50 kgs in total weight and/or less than 1 m3 in total volume. Mass analysis instruments are provided that can include an interface vacuum structure operatively coupled between an ionization source and a vacuum region housing a detector. Mass analysis instruments are also provided that can include an ionization source coupled to an analysis region via an interface vacuum structure, with at least two independent vacuum components.

Abstract: Analyte ions entrained in a carrier gas are analyzed by parallel flow ion mobility spectrometry prior to analysis by a mass analyzer. An extended ion funnel is located in the vacuum system of the mass analyzer and has an ion focusing section and an ion mobility analyzing section. The carrier gas together with entrained ions is introduced into the ion focusing section where the ions are focused to the axis of the funnel by applied RF voltages. In the ion mobility section, the action of an RF quadrupolar field, the movement of the carrier gas and axial DC field, separates the ions on the basis of their mobilities. The mobility separated ions are released into the mass analyzer where the ions may be further separated on the basis of mass.

Abstract: An ion mobility spectrometer comprises an electrode and two storage electrodes disposed at the two opposite sides of the electrode respectively. Ions from an intermediate part between the two storage electrodes are stored and the stored ions are released from the storage electrodes by changing electric potentials of the two storage electrodes. The present invention further discloses a detecting method using an ion mobility spectrometer.

Abstract: A novel high ion storage/ ion mobility separation mass spectrometer that provides for a high duty cycle of operation is presented herein. In particular, the example embodiments, as disclosed herein, provides for a high ion storage/ion mobility instrument that beneficially includes a two-dimensional (2D) plurality of adjacently arranged ion confinement channels to provide a high storage bank of a desired mass range of ions. Such ions, via ion mobility transport, are separated into smaller fractions of an overall mass window into desired confinement regions of the disclosed 2D confinement channels and thereafter transferred out in a manner so as to enable the aforementioned novel high-duty cycle of sequential operation.

Abstract: This invention relates to a mass spectrometer including a reaction cell and to a method of using such a mass spectrometer. In particular, although not exclusively, this invention relates to a tandem mass spectrometer and to tandem mass spectrometry. The invention provides a method of mass spectrometry using a mass spectrometer having a longitudinal axis, comprising guiding ions to travel along the longitudinal axis of the mass spectrometer in a forwards direction to pass through an intermediate ion store and then to enter a reaction cell, to process the ions within the reaction cell, to eject the processed ions to travel back along the longitudinal axis to enter the intermediate ion store once more, and to eject one or more pulses of the processed ions in an off-axis direction to a mass analyser.

Abstract: Used is a sample holder for MALDI mass spectrometry, which has a CuO secondary particle as a laser-beam-absorbing matrix and in which the secondary particle comprises an aggregate of CuO primary particles having an average particle diameter of 100 nm or smaller and has an uneven surface arising from the shape formed by the primary particles constituting the outermost surface of the secondary particle. As the CuO secondary particle, usable is one derived from a CuO powder produced by baking basic copper carbonate in air at 200 to 300° C., and the basic copper carbonate is produced in a process of mixing an aqueous ammonium hydrogencarbonate solution and an aqueous copper nitrate solution. The CuO secondary particle has an average particle diameter of, for example, from 0.3 to 10 ?m.

Abstract: A method of imaging mass spectroscopy and a corresponding apparatus are provided, wherein the m/z-ratio of ions as well as the location of said ions on a sample surface are detected simultaneously in a time of flight mass spectrometer. The detector is a semiconductor array detector comprising pixels, that each can be arranged to measure a signal intensity of a signal induced by the ions or their time of arrival. A four-dimensional image consisting of the two lateral dimensions on the sample surface, the m/z-ratio representing the ion type and the abundance of an ion type on the surface can be reconstructed from repeated measurements for which a correspondingly adapted computer program product can be involved.

Abstract: The invention relates to spatially resolved mass spectrometric measurement and visualization of the distribution of small molecules in a mass range from approximately 150 to 500 Daltons, for example drugs and their metabolites, in thin sections or other two-dimensional samples, preferably with ionization of the molecules by matrix-assisted laser desorption. The invention includes the steps measuring a daughter ion produced by forced decomposition of the molecular ion instead of the ionized analyte molecule itself, the daughter ion having a much better signal-to-noise ratio. The daughter ions are detected in a relatively simple reflector time-of-flight mass spectrometer instead of using an expensive time-of-flight tandem mass spectrometers for the measurement of the daughter ions.

Abstract: Provided is a mass spectroscope employing electron capture dissociation wherein the peak number of detectable fragment ions is increased. The mass spectroscope comprises an ion source (2) for generating ions from a sample, an ion trap (3) for storing and selecting ions, an ion dissociation section (4) performing electron capture dissociation on ions, and a time-of-flight mass spectrometry section (7) performing mass spectrometry on ions, wherein the reaction time of electron capture dissociation is variable depending on the valence of ions subjected to mass spectrometry.

Abstract: The present invention provides a device for measuring a mean free path capable of measuring directly the mean free path of a charged particle, a vacuum gauge, and a method for measuring a mean free path. The device for measuring a mean free path according to one embodiment of the invention includes an ion source for generating an ion, a collector (24a) for detecting the number of first charged particles being charged particles having a first flight distance L1 that is a flight distance of zero or more from the ion source, and a collector (24b) for detecting the number of second charged particles having a second flight distance longer than the first flight distance. The control part of the device calculates the mean free path from a ratio between the numbers of the first and second charged particles.

Abstract: The present invention provides novel radiation associated markers. The radiation associated markers may be one or more of albumin, LTGF-?, or any protein or peptide listed in any one of Tables 1, 2, 3, 4, 5, and 6 provided herein. The present invention also provides methods of assessing exposure to ionizing radiation by determining the presence of one or more radiation associated markers. The methods may optionally include quantifying one or more of the radiation associated markers. The methods may further include comparing the amount of one or more radiation associated markers in the sample determined to be present in the sample with either (i) the amount determined for temporally matched, normal samples or (ii) the amount determined for samples obtained from individuals or subjects that have not been exposed to an elevated level of ionizing radiation. The present invention further provides a method of predicting outcome in a subject after exposure to elevated levels of ionizing radiation.

Abstract: The present invention provides compositions and processes for preparing the same wherein the compositions are useful for monitoring breast cancer treatment.

Abstract: A variety of ions generated in an ion source are made to fly while bypassing a loop orbit and mass analyzed to create a mass spectrum. Among the peaks appearing on the mass spectrum, peaks complying with predetermined conditions are extracted to determine a plurality of mass ranges to be measured (S1 through S3). Next, the ion selection conditions for the timing when ions should be injected into the loop orbit and on the loop orbit are determined for each mass range. In addition, deviation conditions under which selected ions will not be mixed are determined (S4 and S5). When the second measurement is performed for the same sample, ions are put into the loop orbit and unnecessary ions are removed from the loop orbit in accordance with the ion selection conditions (S6 and S7). Thus, only the ions to be measured are left on the loop orbit with a high mass resolving power.

Abstract: A differential ion mobility spectrometry or field asymmetric waveform ion mobility spectrometry (FAIMS) platform is disclosed that utilizes both gas flow and electric field, consecutively or simultaneously, to move ions through the analytical gap. The consecutive combination of flow and field enables rapid and flexible switching of the FAIMS stage “on” (for ion separation) and “off” (for high non-selective transmission) with no hardware modifications. This capability is needed for effective use of multidimensional instrument systems that couple FAIMS to mass spectrometry and/or conventional ion mobility spectrometry. The joint application of flow and field allows controlling the discrimination against high-mobility ions, maximizing it to remove the chemical noise or minimizing it to make the analyses of complex samples more predictable and uniform.

Abstract: In a time-of-flight spectrum obtained when the overtaking of ions of different kinds has occurred, mass-to-charge ratios M1, M2, and M3 are computed with a predetermined conversion formula by using a plurality of assumed numbers of turns for one peak. Then, the flight times Tf1, Tf2, and Tf3 for an overtakingless measurement are computed by using an inverse conversion formula. If peaks respectively corresponding to the flight times Tf1, Tf2, and Tf3 for an overtakingless measurement exist on an overtakingless time-of-flight spectrum, their intensities i1, i2, and i3 are obtained. Then, the intensity Ia of the original peak is distributed to the mass-to-charge ratios M1, M2, and M3 in accordance with the intensity ratio. The same intensity distribution processing is performed for all or selected plural peaks. The intensities assigned to the same mass-to-charge ratio are integrated.

Abstract: A mass spectrometry apparatus configured to allow a user to designate an upper limit value UL together with a lower limit value, as a peak sorting condition. A data processing section is operable to determine whether respective peak intensities of a plurality of peaks appearing on a mass spectrum fall within an intensity range Ath defined by upper and lower limit values UL, LL, and exclude any peak out of the intensity range Ath. The remaining ions are selected as precursor ions, for example, in descending or ascending order of peak intensity so as to perform an MS2 analysis. The upper limit UL is adequately set to allow the MS2 analysis for a sample component with a low concentration, by priority, while avoiding a sample component exhibiting a high intensity and having no need for the MS2 analysis.

Abstract: A smart FAIMS sensor system and method includes a 2/2-electrode filter that pumps the ions through the system and separates the ionic species, a detector for collecting the separated ions and generating a detector signal in response to the collected ions, and a controller configured to change the operating parameters of the system in response to changes in the sensor's environment detected by the sensor. The ability to dynamically change the operating parameters of the sensor enables the sensor to maintain high sensitivity to environmental threats while decreasing the incidences of false positive events.

Abstract: Provided herein is a bladed ion slicer for blocking ions in an ion beam that have significant distance from the beam axis. In certain embodiments, the bladed ion slicer comprises a body; a first elongated blade; and a second elongated blade; wherein the ion slicer comprises a slit that extends through the body through which ions pass and wherein the edges of the first and second elongated blades define the entrance of the slit and are pointing towards the ion beam. A mass spectrometer system and method for removing unwanted ions are also provided.

Abstract: Described herein is an ion slicer that: a) accelerates an ion beam towards a first electrode comprising an ion entrance slit, where the first electrode blocks a portion of ions with high displacement from the axis of the ion beam, thereby slicing the ion beam; and then b) decelerates the ion beam after it is sliced.

Abstract: There is provided a time-of-flight mass spectrometer of a simple configuration and low cost that prevents temperature drift and provides stable mass spectrum without the use of expensive Invar material for the flight tube which nevertheless is not easily affected by external vibrations and does not deflect under its own weight when held as a cantilever. The flight-tube is made of a CFRP pipe 17a whose inner and outer surfaces are provided with an electroless nickel-plated layer 17b as an electroconductive treatment. Electroconductive adhesive 21 is used for joining to flight-tube holding member 18. Unlike previous flight-tubes made of metal, flight-tubes made of CFRP pipe 17a do not deform even when no temperature adjustment and control system is used. Also, since the specific gravity of CFRP is only about one-fifth of that of stainless steel, the flight-tube does not easily deflect even when it is held as a cantilever.

Abstract: The main voltage generator (5) applies a rectangular-wave radio-frequency voltage to the ring electrode (21) in order to capture ions inside the ion trap (2). In the case where the TOFMS (3) is operated in the reflectron mode, the radio-frequency voltage is changed into a constant voltage value when the phase thereof is 1.5?, and a voltage for expelling ions is applied to the end cap electrodes (22, 23) to expel the ions from the exit aperture (25) and introduce them into the TOFMS (3). In this case, since the velocity spread of the ions inside the ion trap (2) is small and so is the spatial spread thereof, a high mass resolution and accuracy can be achieved while assuring a high detection sensitivity. In the case where the TOFMS (3) is operated in the linear mode, the radio-frequency voltage is changed into a constant voltage value when the phase thereof is 0.5?, and then the ions are expelled.

Abstract: The present invention pertains to a method and apparatus which increases the efficiency with which ions are transported from a first ion trap to a second ion trap, and subsequently trapped in the second ion trap. In one aspect the invention, increased efficiency takes the form or enabling ions of both high and low mass to charge ratios to be trapped in the second ion trap at substantially the same time, or at least within a relatively small window of time. This can be achieved by minimizing the undesirable time-of-flight separation by the high and low mass to charge ratio ions as they are transported from a first ion trap to the second ion trap. This minimization can be realized by adjusting the potential energy applied to ion transfer optics disposed between the two ion traps.

Abstract: The present invention involves a series of shifting reagents that selectively interact with a targeted functional group of biological molecules, pharmaceutical drugs, small molecules, chemicals, chemical agents, or explosives resulting in a structure selective based drift time shift in the IMS. The invention allows detecting and confirming samples using one or more ion mobility based spectrometers.

Abstract: A micro-reflectron for a time-of-flight mass spectrometer including a substrate and integrated with the volume of the substrate, means for application of a potential gradient in a volume suitable for constituting a flight zone of the ions. The means of application includes at least two polarization electrodes and a wall of at least one resistive material that can be polarized between these electrodes so as to generate a continuous potential gradient, itself providing the function of reflectron, this flight zone, these electrodes and this wall being obtained by the technology of microelectromechanical systems (MEMS) and this micro-reflectron having a thickness of less than 5 millimetres while its other dimensions are less than 10 times this thickness.

Abstract: An ion guide or ion trap is disclosed having an entrance electrode and an exit electrode. The potential of the exit electrode is periodically dropped for a relatively short period of time allowing some ions to escape from the ion guide or ion trap via an aperture in the exit electrode. The period of time that the potential of the exit electrode is dropped for is progressively increased and ions emerge from the ion guide or ion trap in a mass to charge ratio dependent manner. The ion guide or ion trap may be operated as a mass separator or low resolution mass analyser.

Abstract: A multi-reflecting ion optical device includes electrostatic field generating means configured to generate electrostatic field defined by a superposition of first and second distributions of electrostatic potential ?EF, ?LS. The first distribution ?EF subjects ions to energy focusing in a flight direction and the second distribution ?LS subjects ions to stability in one lateral direction, to stability in another lateral direction for the duration of at least a finite number of oscillations in the one lateral direction and to subject ions to energy focusing in the one lateral direction for a predetermined energy range.

Abstract: A method and apparatus for time-of-flight (TOF) mass spectrometry. The apparatus improves the ion focusing properties in an orthogonal direction and permits connection with an orthogonal-acceleration ion source for improvement of sensitivity. The apparatus comprises an ion source for emitting ions in a pulsed manner, an analyzer for realizing a helical trajectory, and a detector for detecting the ions. The analyzer is composed of plural laminated toroidal electric fields to realize the helical trajectory.

Abstract: Methods for fragmenting ions retained in an ion trap are described. In various embodiments, a non-steady-state pressure of a neutral collision gas of less than about 5×10?4 Torr and an excitation amplitude of less than about 500 mV (peak to ground) is used to fragment ions with greater than about 80% fragmentation efficiency. In various embodiments, duration of ion excitation is greater than about 25 ms.

Abstract: A device and associated methods of operations are disclosed for interfacing on ion trap to a mass analyzer, such as a TOF mass analyzer. The device includes a plurality of sequentially arranged confinement cells having fixed locations. A group of ions, e.g., ions within a relatively narrow window of mass-to-charge ratio, is received by the device from the ion trap, undergoes fragmentation, and is transported through the device from a first to final confinement cell by a series of transfers between adjacent cells. The ion group is confined in each cell for a prescribed cooling period. By providing a suitable aggregate ion confinement time and by enabling concurrent transport and cooling of successively ejected ion groups, the ions are cooled sufficiently to enable the acquisition of mass spectra at high resolution, without having to substantially delay the ejection of a subsequent group of ions from the ion trap until cooling of the previous group is completed.

Abstract: Prior work on differential mobility analysis (DMA) combined with mass spectrometry (MS) has shown how to couple the output of a planar DMA with the atmospheric pressure inlet of an atmospheric pressure ionization mass spectrometer (APCI-MS). However, because the ion inlet to APCI-MS instruments is a round orifice, while conventional DMA geometries make use of elongated slits, the coupling of both has attained less resolving power or tolerated a smaller sample flow rate than a DMA alone. The present invention overcomes these limitations with an axial DMA of cylindrical symmetry using more than two electrodes. The configuration is related to that previously proposed by Labowsky and Fernández de la Mora (2004, 2006), where ions with a critical electrical mobility are brought into the symmetry axis of the DMA. Ions with this critical mobility are now optimally transmitted into the MS, with much higher resolution than possible in planar DMAs.

Abstract: An ion injection spray apparatus and method are provided for coupling a liquid chromatograph or other liquid flow device to a mass spectrometer. The ion injection spray assembly is composed in part of a chamber for voltage and gas input, a metal union for a liquid voltage junction, a gas distribution assembly, a vacuum seal and an ion spray needle. The position of the ion spray needle within this assembly is directly coupled to the outlet of the upstream liquid flow device through the metal union. The vacuum of the mass spectrometer pulls gas at atmospheric pressure though the gas distribution assembly to focus the sample liquid at the spray needle outlet and create a centrifugal gas funnel which helps to desolvate the sample ions and sweep them into the mass spectrometer over a wide range of flow rates.