423results about "Tube calibration apparatus" patented technology

In a method for optimizing an ion detector a control voltage, such as in a mass spectrometry system, an array of mass scan data is acquired. Based on the size of the largest peak in the array or part of the array, a determination is made as to whether the current detector gain should be changed to a new detector gain. If the current detector gain should be changed, the control voltage for the subsequent mass scan is adjusted to a new control voltage corresponding to the new detector gain. The data are scaled based on the current detector gain. In another method, a gain versus control voltage curve is generated for calibration. These methods may be implemented by hardware, software, analog or digital circuitry, and / or computer-readable or signal-bearing media.

A method for calibrating and analyzing data from a mass spectrometer, comprising the steps of acquiring raw profile mode data containing mass spectral responses of ions with or without isotopes; calculating theoretical isotope distributions for each of at least one calibration ion based on elemental composition; convoluting the theoretical isotope distributions with an initial peak shape function to obtain theoretical isotope profiles for each ion; constructing a peak component matrix including the theoretical isotope profiles for calibration ions as peak components; performing a regression analysis between the raw profile mode mass spectral data and the peak component matrix; and reporting the regression coefficients as the relative concentrations for each of the components. A mass spectrometry system operated in accordance with the method and a computer readable medium having program code thereon for performing the method.

A method of calibrating ion collision energy used in a mass spectrometer, comprises: (a) obtaining fragment ion yield data for each of a plurality of precursor ion populations having respective mass-to-charge ratios at each of a plurality of settings of a fragmentation-energy-related variable; (b) locating, for each mass-to-charge ratio, reference values of the fragmentation-energy-related variable, each reference value corresponding to a respective reference feature of the ion yield data at the mass-to-charge ratio; (c) determining, from the plurality of locating steps, the variation, with mass-to-charge-ratio, of each of the reference values of the fragmentation-energy-related variable; (d) associating each of the reference values of the fragmentation-energy related variable with respective reference values of a dimensionless useable-fragmentation-energy variable; and (e) storing parameters describing the variation of each of the reference values of the fragmentation-energy-related variable with mass-to-charge ratio, wherein the parameters comprise coefficients of at least one non-linear equation.

Accurate mass measurement is carried out for product ions of a sample. A method for accurate mass determination of ions with Trap-TOF / μs includes steps of generating ions of an analyte sample and a standard material; introducing the ions of the analyte sample and the standard material together into an ion trap to trap them; selecting a precursor ion from the ions of the analyte sample to leave the precursor ion and a standard material ion in the ion trap and eliminate other ions; exciting and dissociating the precursor ion to generate product ions; ejecting the precursor ion, its product ions, and the standard material ion trapped in the ion trap to introduce these ions into the TOF mass spectrometer; and measuring a mass spectrum with the TOF mass spectrometer, where correction for accurate masses of the product ions is carried out based on the standard material ion measured.

The invention relates to a new type of element encoded particles suitable for the attachment of bio molecules to enable massively multiplex bio-analytical methods, and to calibrate and tune the elemental flow cytometer mass spectrometer (FC-MS).

A method for calibrating and analyzing data from a mass spectrometer, comprising the steps of acquiring raw profile mode data containing mass spectral responses of ions with or without isotopes; calculating theoretical isotope distributions for each of at least one calibration ion based on elemental composition; convoluting the theoretical isotope distributions with an initial peak shape function to obtain theoretical isotope profiles for each ion; constructing a peak component matrix including the theoretical isotope profiles for calibration ions as peak components; performing a regression analysis between the raw profile mode mass spectral data and the peak component matrix; and reporting the regression coefficients as the relative concentrations for each of the components. A mass spectrometry system operated in accordance with the method and a computer readable medium having program code thereon for performing the method.

The use of a robust statistical method for self-calibration of a measuring instrument, such as a mass spectrometer, is disclosed. The method involves the use of differences in mass and complementary pairs for example, to estimate calibration parameters. Self-calibration of various mass spectra is described. Related systems and computer-readable media are also described.

A method of calibrating a TOF-MS mass spectrum, to account for temperature changes, is disclosed. Ions are introduced into a Fourier Transform Mass Spectrometer and their mass to charge ratios are determined. Ions, including calibrant ions, are also introduced into a time of flight mass spectrometer and the mass to charge ratios of the calibrant ions at least are also determined. Specific peaks representative of calibrant ions are selected and matched between the TOF MS and FTMS spectra. The relative position of matched peaks in each spectrum is then used to determine a temperature correction factor for the TOF MS data, based upon the relative independence of the FTMS spectrum with respect to temperature.

This invention relates generally to multi-reflection electrostatic systems, and more particularly to improvements in and relating to the Orbitrap electrostatic ion trap. A method of operating an electrostatic ion trapping device having an array of electrodes operable to mimic a single electrode is proposed, the method comprising determining three or more different voltages that, when applied to respective electrodes of the plurality of electrodes, generate an electrostatic trapping field that approximates the field that would be generated by applying a voltage to the single electrode, and applying the three or more so determined voltages to the respective electrodes. Further improvements lie in measuring a plurality of features from peaks with different intensities from one or more collected mass spectra to derive characteristics, and using the measured characteristics to improve the voltages to be applied to the plurality of electrodes.

A mass analysis of a standard sample having a known mass-to-charge ratio is carried out by performing a mass scan at a first-stage quadrupole (13) over a predetermined mass range, under the condition that a collision induced dissociation (CID) gas is introduced into a collision cell (14) and a voltage applied to a third-stage quadrupole (17) is set so that no substantial mass separation occurs in this quadrupole. Various kinds of product ions originating from a precursor ion selected by the first-stage quadrupole (13) arrive at and are detected by a detector (18) without being mass separated. Accordingly, based on the detection data, a data processor (25) can obtain a relationship between the voltage applied to the first-stage quadrupole (13) and the mass-to-charge ratio of the selected ions, with a time delay in the collision cell (14) reflected in that relationship. This relationship is stored in a calibration data memory (26), to be utilized in a neutral loss scan measurement or the like. By using this relationship, a mass shift due to the time delay in the collision cell (14) can be cancelled, so that the product ions can be detected with high sensitivity over the entire mass range. Furthermore, a mass spectrum having an accurate mass axis can be created.

The present invention provides methods for high throughput analysis of analytes in complex mixtures for unresolved chromatographic peaks including specific embodiment for summing intensities for each mass transition of interest over a selected chromatographic peak (50) to generate a signal corresponding to total intensity for each transition (55, 60). The intensities are deconvoluted into intensities of individual analytes (65, 70), based on branching ratios acquired from authentic standards, and a comparison to calibration curve is performed to obtain a quantitative concentration measurement of a particular analyte in a sample.

A mass analysis of a sample having a known mass-to-charge ratio is carried out by performing a scan at a first-stage quadrupole over a predetermined mass range, under the condition that a collision induced dissociation gas is introduced into a collision cell and a voltage applied to a third-stage quadrupole is set so that no substantial mass separation occurs in this quadrupole. Various product ions originating from a precursor ion selected by the first-stage quadrupole arrive at and are detected by a detector without being mass separated. Accordingly, based on the detection data, a data processor can obtain a relationship between the voltage applied to the first-stage quadrupole and the mass-to-charge ratio of the selected ions, with a time delay in the collision cell reflected in that relationship. This relationship is stored in a calibration data memory, to be utilized in a neutral loss scan measurement or the like.