32results about "Accelarator mass spectrometers" patented technology

The invention provides a calibrating method for use in a method of determining the quantity of an analyte labelled with an AMS isotope in a test sample, said calibrating method comprising: (i) contacting a plurality of samples contaminated with neither said analyte nor a non-labelled counterpart analyte with a known quantity of said counterpart analyte and a quantity C of analyte to afford a plurality of calibrating samples, wherein each of said calibrating samples contains a known quantity of counterpart analyte but a different quantity of C; (ii) measuring by AMS the quantity C of analyte added to each of the plurality of samples; (iii) separating the analyte and counterpart analyte from other species in the plurality of samples to afford a plurality of purified samples; (iv) measuring a quantity A of analyte in said purified samples by AMS; and (v) measuring a quantity B of counterpart analyte in said purified samples.

This invention relates to a method and apparatus for separation of rare stable or radioactive isotopes from their atomic or molecular isobars in mass spectrometry (MS). In the present invention, the approach taken to removing atomic isobars utilizes a high transmission device for decelerating ions in combination with low energy reactions, such as ion-molecule reactions or near resonant electron transfer, in RF ion guides. The isobar is selectively depleted by electron transfer or other reactions between negative ions and gaseous targets in pressurized RF ion guides at low energies. The energy is controlled in such a way as to prevent reaction of the ion of interest while inducing reactions with the undesired isobar interference. The technique is of particular relevance to accelerator mass spectrometry (AMS) for which it allows substantial reductions in the necessary terminal voltage. The effect is to allow reductions in the size and cost of AMS installations.

The analyst previously enters the mass of a fragment that desorbs in the first dissociation with other analysis conditions, as the precursor ion selection reference for the second dissociation through the input unit 25. When the automatic analysis is started, the controller unit 21 sequentially performs the MS1 analysis, MS2 analysis and MS3 analysis. In the course of these analyses, the data processing unit 23 determines the valence of each ion species corresponding to the peaks appearing in the mass spectrum obtained by the MS1 analysis. In addition, after the MS2 analysis, the data processing unit 23 searches for the ion species in conformity with the selection reference in consideration of the determined valence, among the ion species corresponding to the peaks appearing in the mass spectrum by the MS2 analysis. The selected ion is determined as the precursor ion for the second dissociation in the MS3 analysis. In this manner, regardless of the valence of the target ion, the precursor ions to be selected and dissociated in each stage of the MSn analysis are automatically selected according to the mass of the fragment desorbed in the dissociation in the previous stage. Therefore, the analytical efficiency is improved and the highly accurate chemical structure information can be obtained.

The present invention relates to improved methods for measuring the renewable bio-source carbon content and renewable bio-content in renewable bioplastic resins produced in manufacturing plants. In particular, the present invention relates to measuring the renewable bio-source carbon content in renewable bioplastic resins produced during a production run by correlating measured δ13C values are measured by iTOC-CRDS and CM-CRDS with actual renewable bio-source carbon content measurements (AMS or LSC14C) via a linear regression.

A method of treating a particle beam is disclosed, of interest in particular for mass spectrometry for 14C. A particle beam including positive ions is passed through a charge exchange cell containing a target gas. The target gas is electrically insulating at room temperature and pressure. At least some of the positive ions of the particle beam are converted to negative ions by interaction with the target gas. The particle beam incident at the charge exchange cell includes molecules and / or molecular ions which interact with the target gas to reduce the concentration of molecules as a result of repeated collisions with particles of the target gas. A corresponding mass spectrometry system is also disclosed.

The present invention provides a method of sample preparation for use in obtaining elemental isotope ratios of a material by accelerator mass spectrometry. The method comprises forming the material into a sample without any substantial chemical alteration of the material. The invention also provides a sample for use in obtaining elemental isotope ratios of a material.

An accelerator mass spectrometry system for measuring an isotopic ratio of a chemical element in a sample. The system includes an ion source generating a beam of negative ions of the chemical element containing ions of first and second isotopes of the chemical element, a first analyzer section, comprising a first mass analyzer; a tandem accelerator comprising a first accelerating section, a charge stripping section for converting the negative ions into positive ions, and a second accelerating section behind the charge stripping section. A second analyzer section includes a second mass analyzer and an electrostatic analyzer; a particle detector; and a controller system configured to control the first mass analyzer section and the second analyzer section such that the ions of the first and second isotopes traverse the tandem accelerator and ions of only one of the first and second isotopes enter the particle detector. An additional analyzer is located in between the charge stripping section and the second accelerating section and is configured to receive positive ions that have exited the charge stripping section and to separate positive ions having a charge state corresponding to a predetermined charge-state value from positive ions having a charge state not corresponding to the predetermined charge-state value, so as to transmit ions with different charge states in mutually different directions such that only ions having a charge state corresponding to the predetermined charge-state value are transmitted towards the particle detector.

An object of the present invention is to provide a mass spectrometer and a mass separator whose design and performance are less restricted by problems arising from the principle of operation, and which have in principle no limitation on the mass-to-charge ratio range to be able to deal with and are each capable of repeatedly analyzing or extracting plural ionic species of different mass-to-charge ratios in a short time.A mass spectrometer (10) is configured from an ion source (1), an ion introduction unit (2), a mass analyzer (3), an ion detection unit (4), and the like. Crude ions are introduced into a separation space (5) at a predetermined acceleration voltage as a pulse synchronized with the phase of a one-dimensional high-frequency electric field. In the separation space (5), each ion travels in an incident direction by inertia, and besides they are displaced by force received from the one-dimensional high-frequency electric field which acts in the y-direction crossing the incident direction. Ionic species having different mass-to-charge ratios with each other are separated by the difference in displacement magnitude. At this time, the acceleration voltage and the period of the one-dimensional high-frequency electric field are set in order that the measured ionic species may exit from the separation space (5) having received the action of the electric field for one period.

An isotope mass spectrometer including: an electron cyclotron resonance ion source, a front-end analysis device, a back-end analysis device and an ion detector; where the electron cyclotron resonance ion source is connected with the front-end analysis device, and is used for generating ion beams of multivalent charge states; the front-end analysis device is connected with the back-end analysis device, selects and separates the ion beams, and receives ion beams of constant, microscale and trace levels; the back-end analysis device is connected with the ion detector, and is used for eliminating a background of an isotope to be measured at an ultratrace level; and the ion detector is used for receiving ion beams of the ultratrace level, and carrying out energy measurement and separation on the ion beams of the ultratrace level, so as to obtain the isotope to be measured at the ultratrace level.

A method of treating a particle beam is disclosed, of interest in particular for mass spectrometry for 14C. A particle beam including positive ions is passed through a charge exchange cell containing a target gas. The target gas is electrically insulating at room temperature and pressure. At least some of the positive ions of the particle beam are converted to negative ions by interaction with the target gas. The particle beam incident at the charge exchange cell includes molecules and / or molecular ions which interact with the target gas to reduce the concentration of molecules as a result of repeated collisions with particles of the target gas. A corresponding mass spectrometry system is also disclosed.

The present invention relates to improved methods for measuring the renewable bio-source carbon content and renewable bio-content in renewable bioplastic resins produced in manufacturing plants. In particular, the present invention relates to measuring the renewable bio-source carbon content in renewable bioplastic resins produced during a production run by correlating measured δ13C values are measured by iTOC-CRDS and CM-CRDS with actual renewable bio-source carbon content measurements (AMS or LSC 14C) via a linear regression.

An accelerator mass spectrometry system for measuring an isotopic ratio of a chemical element in a sample. The system includes an ion source generating a beam of negative ions of the chemical element containing ions of first and second isotopes of the chemical element, a first analyzer section, comprising a first mass analyzer; a tandem accelerator comprising a first accelerating section, a charge stripping section for converting the negative ions into positive ions, and a second accelerating section behind the charge stripping section. A second analyzer section includes a second mass analyzer and an electrostatic analyzer; a particle detector; and a controller system configured to control the first mass analyzer section and the second analyzer section such that the ions of the first and second isotopes traverse the tandem accelerator and ions of only one of the first and second isotopes enter the particle detector. An additional analyzer is located in between the charge stripping section and the second accelerating section and is configured to receive positive ions that have exited the charge stripping section and to separate positive ions having a charge state corresponding to a predetermined charge-state value from positive ions having a charge state not corresponding to the predetermined charge-state value, so as to transmit ions with different charge states in mutually different directions such that only ions having a charge state corresponding to the predetermined charge-state value are transmitted towards the particle detector.

The double-injection tadem accelerator mass spectrometer is characterized by that its injection system comprises double-focussing speed analzer, static quadrupole lens and mass recombiner. On the premise of no changing detected nuclide species and accuracy said inventino can reduce its cost, and possesses the advantages of simpe structure and operation, and is applicable to detection analysis of various long-life radionuclides.

A shielding plate 6 having a forward-side slit opening 61 and return-side slit opening 62 is placed in a free flight space 3 with no electric field. Ions which significantly deviate from a reference path are removed by the shielding plate 6 on both the forward-side and return-side paths. The opening width of the forward-side slit opening 61 is smaller than that of the return-side slit opening 62. Those opening widths and the placement position of the shielding plate 6 are determined based on the result of an ion trajectory calculation by accurate simulation. As compared to a conventional device with a shielding plate placed only on the return side, the present configuration allows for an increase in the opening width of the return-side slit opening while achieving the same level of resolving power. The ion transmission ratio is thereby improved, and the analytical sensitivity is enhanced.

Disclosed herein is a method for evaluating and measuring the performance, efficacy and safety of candidate new chemical entities. This method comprises employing a target compound having one or more 12C atoms in the molecule wherein at least one of the 12C atoms is substituted with a 13C atom, The stable labelled target compound is then administered to a test subject following which the target compound and / or one or more of its metabolites are recovered using conventional separation techniques and purified. The resulting isolated material of interest is then combusted in the presence of a petrochemical based carrier, the 12C content of such carrier with respect to naturally occurring 13C being in excess of 99.9 percent. The CO2 resulting from such combustion is then graphitized and the graphitized material is analyzed employing techniques, such as Accelerator Mass Spectrometry (“AMS”), capable of differentiating and counting the carbon atom isotopes (13C vs. 12C), thus allowing quantification of the compound / metabolite of interest.