1166 results about "Mass" patented technology

A new geometry ion trap and its use as a mass spectrometer is described. The ion traps can be combined linearly and in parallel to form systems for mass storage, analysis, fragmentation, separation, etc. of ions. The ion trap has a simple rectilinear geometry with a high trapping capacity. It can be operated to provide mass analysis in the mass-selective instability mode as well as the mass-selective stability mode. Arrays of multiple ion traps allow combinations of multiple gas-phase processes to be applied to the trapped ions to achieve high sensitivity, high selectivity and / or higher throughput in the analysis of ions.

A system and method for analyzing and imaging a sample containing molecules of interest combines modified MALDI mass spectrometer and SNOM devices and techniques, and includes: (A) an atmospheric-pressure or near-atmospheric-pressure ionization region; (B) a sample holder for holding the sample; (C) a laser for illuminating said sample; (D) a mass spectrometer having at least one evacuated vacuum chamber; (E) an atmospheric pressure interface connecting said ionization region and said mass spectrometer; (F) a scanning near-field optical microscopy instrument comprising a near-field probe for scanning the sample; a vacuum capillary nozzle for sucking in particles which are desorbed by said laser, the nozzle being connected to an inlet orifice of said atmospheric pressure interface; a scanner platform connected to the sample holder, the platform being movable to a distance within a near-field distance of the probe; and a controller for maintaining distance information about a current distance between said probe and said sample; (G) a recording device for recording topography and mass spectrum measurements made during scanning of the sample with the near-field probe; (H) a plotting device for plotting said topography and mass spectrum measurements as separate x-y mappings; and (I) an imaging device for providing images of the x-y mappings.

The present invention discloses methods for deconvolving and converting 1D mass spectra to 2D mass spectrum in order to obtain migration time centers and total intensities of the neutral mass envelopes of 2D spectra. The present invention also discloses devices that include a preparation / separation unit coupled to a mass spectrometer unit, and a computer unit capable of deconvolving mass spectra and calculating neutral mass envelopes.

In a tandem mass spectrometer ions are created only once and stored in an ion reservoir. A particular ion species to be analyzed is then exported from the reservoir through a mass selective ion gate without damaging the other ion species remaining in the reservoir. All subsequent analyses are conducted on these stored ions, without adding further ions so that no changes in the concentrations of the stored ion species occur. The exported ions are fragmented, and a fragment ion mass spectrum is measured in a mass analyzer, preferably in a time-of-flight mass analyzer with orthogonal ion injection. The processes of exporting a selected ion species with subsequent fragmentation and the acquisition of the fragment ion spectrum can be repeated for any number of ion species stored in the reservoir.

A method and apparatus are provided for effecting multiple mass selection or analysis steps. Fundamentally, the technique is based on moving ions in different directions through separate components of a mass spectrometer apparatus. To effect different steps, a precursor ion is selected in a first mass selector, and then passed into a collision cell, to effect fragmentation or reaction with a gas, to generate fragment or product ions. The generated product ions are then passed back into the first mass selector, and preferably back into an upstream ion trap. The product ions then pass through the first mass selector again, to select a desired product ion, for further fragmentation and analysis. These steps can be repeated a number of times. A final mass analysis step can be effected in either a time-of-flight section or other mass analyzer. The invention enables conventional triple quadrupole mass spectrometers and QqTOF mass spectrometers to effect multiple MS steps.

A method for reproducibly analyzing mass spectra from different sample sources is provided. The method deconvolutes the complex spectra by collapsing multiple peaks of different molecular mass that originate from the same molecular fragment into a single peak. The differences in molecular mass are apparent differences caused by different charge states of the fragment and / or different metal ion adducts and / or reactant products of one or more of the charge states. The deconvoluted spectrum is compared to a library of mass spectra acquired from samples of known identity to unambiguously determine the identity of one or more components of the sample undergoing analysis.

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.

An MALDI mass spectrometer for the composition analysis of large batch sizes of samples includes a mass spectrometer having an ionization chamber and a sample chamber coupled to the ionization chamber. A transport cart is positioned in the sample chamber with a sample cassette removably coupled thereto. A method of operating a MALDI mass spectrometer is also disclosed.

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.

The invention covers a method for detecting ions in high resolution time-of-flight mass spectrometers which operate with secondary electron multiplier multichannel plates and in which many single spectra are acquired and added to produce a sum spectrum. The invention involves (a) using an analog digital converter (ADC) for converting electron currents from secondary electron multipliers, instead of a time-to-digital converter (TDC) which was previously used for highest possible signal resolution, (b) performing a separate rapid peak recognition procedure for the ion signals of each spectrum by a fast calculation method, thereby collecting flight time and intensity value pairs for the ion peaks, and (c) constructing a time-of-flight / intensity histogram, which is further processed as a composite time-of-flight spectrum. The invention retains the significantly higher measurement dynamics of an ADC and achieves the improved resolution capability of a TDC, but without showing the latter's known signal distortion due to dead times.

A mass spectrometer has an atmospheric pressure chemical ionization source that includes a first ionization portion including a needle electrode, for generating a primary ion by discharge of the needle electrode a primary ion introduction aperture, and a second ionization portion including an introduction aperture, for generating a sample ion by the reaction between the primary ion and the sample gas introduced from an end of a column of gas chromatography, a sample ion movement aperture; and a mass analysis portion; wherein the end is arranged at a position satisfying the relation r≦2R where R is a radius of an inner diameter of the aperture and r is a distance between an axis connecting the center of the aperture and the center of the aperture, and the end.

A mass spectrometer includes an ion source, an extraction device, a TOF mass analyzer, an ion trap mass analyzer, and an ion guiding optical element which guides at least one of extracted ions from the ion source and extracted ion fragments into the TOF mass analyzer in a normal mode of operation and into the IT mass analyzer in a tandem mode of operation. The apparatus operates by producing ions from a sample, extracting the ions from the ion source, selecting between the TOF mass analyzer and the IT mass analyzer, directing extracted ions to the selected mass analyzer, mass-separating the directed ions and fragments of the directed ions according to a mass-to-charge ratio, detecting mass-separated ions with the selected mass analyzer, and producing at least one of a normal mass spectrum and a tandem mass spectrum.

A new ionization source named Surface Activated Chemical Ionization (SACI) has been discovered and used to improve the sensitivity of the mass spectrometer. According to this invention the ionization chamber of a mass spectrometer is heated and contains a physical new surface to improve the ionization process. The analyte neutral molecules that are present in gas phase are ionized on this surface. The surface can be made of various materials and may also chemically modified so to bind different molecules. This new ionization source is able to generate ions with high molecular weight and low charge, an essential new key feature of the invention so to improve sensitivity and reduce noise. The new device can be especially used for the analysis of proteins, peptides and other macromolecules. The new invention overcomes some of the well known and critical limitations of the Electrospray (ESI) and Matrix Assisted Laser Desorption Ionization (MALDI) mass spectrometric techniques.

A mass spectrometry method is disclosed in which a voltage signal from an ion detector is analyzed. The second order differential of each voltage signal was obtained and the onset and end times of the observed voltage peaks were determined. The intensity and average time of each voltage peak are then determined and the intensity and time values ​​are stored. An intermediate composite mass spectrum was then formed by combining the intensity and time values ​​associated with each voltage peak observed from multiple experimental runs. Each time and intensity data pair is then integrated to produce a smooth continuum. The continuum can then be further processed by determining the second differential of the continuum. The start and end times of mass peaks observed in a continuum mass spectrum can be determined. The intensity and mass-to-charge ratio of each mass peak observed in the continuum can then be determined. A final discrete mass spectrum including only the intensity values ​​and mass-to-charge ratios for each ion can then be displayed or output.

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 for analyzing analytes from a sample introduced into a Spectrometer by generating a pseudo random sequence of a modulation bins, organizing each modulation bin as a series of submodulation bins, thereby forming an extended pseudo random sequence of submodulation bins, releasing the analytes in a series of analyte packets into a Spectrometer, thereby generating an unknown original ion signal vector, detecting the analytes at a detector, and characterizing the sample using the plurality of analyte signal subvectors. The method is advantageously applied to an Ion Mobility Spectrometer, and an Ion Mobility Spectrometer interfaced with a Time of Flight Mass Spectrometer.

A method, apparatus and algorithms are disclosed for operating an open electrostatic trap (E-trap) or a multi-pass TOF mass spectrometer with an extended flight path. A string of start pulses with non equal time intervals is employed for triggering ion packet injection into the analyzer, a long spectrum is acquired to accept ions from the entire string and a true spectrum is reconstructed by eliminating or accounting overlapping signals at the data analysis stage while using logical analysis of peak groups. The method is particularly useful for tandem mass spectrometry wherein spectra are sparse. The method improves the duty cycle, the dynamic range and the space charge throughput of the analyzer and of the detector, so as the response time of the E-trap analyzer. It allows flight extension without degrading E-trap sensitivity.