Hitachi, Ltd.

Hitachi-high-technologies Corporation

Tadao Mimura

Yoshiaki Kato

Yasuaki Takada

Minoru Sakairi

Kiyomi Yoshinari

Takayuki Nabeshima

Masaru Tomioka

Masayoshi Yano

Hideaki Koizumi

Yoichi Ose

Kazumi Matsumura

Fumihiko Nakajima

Mitsuru Oonuma

Kazunori Hashimoto

Tomoyuki Miyata

Atsumu Hirabayashi

Mitsuru Ohnuma

Toyoharu Okumoto

Seiji Kamimura

Shinji Nagai

Toshihiro Ishizuka

An ion trap/time-of-flight mass spectrometer, which can perform accurate mass measurement of a product ion based on MS/MS and MShas an ion source for ionizing a sample, an ion trap capable of temporarily trapping ions, and a time-of-flight mass spectrometer. The ion source produces ions of the sample as a measurement target and ions of a reference sample each having a known mass value. A precursor ion is selected from among the ions of the measurement target sample, and the selected precursor ion is excited and fragmented in the ion trap to produce a product ion. The reference sample ions are introduced to and trapped in the ion trap. The trapped product ion and reference sample ions are expelled out of the ion trap and introduced to the time-of-flight mass spectrometer, thereby obtaining a mass spectrum.

Ion trap/time-of-flight mass spectrometer and method of measuring ion accurate mass

An ion-trap mass analyzing apparatus having means for generating ion-capture electric fields asymmetrical with respect to a reference plane containing a central point of a ring electrode and perpendicular to a central axis of the ring electrode in the inside of an ion trap to resonantly amplify ions rapidly to emit the ions from the ion trap in a short time to thereby permit high-sensitive high-accurate mass analysis stably regardless of the structural stability of ions as a subject of analysis.

Ion trap mass analyzing apparatus

An ion trap mass spectrometer and spectrometry capable of dissociating ions to be dissociated efficiently regardless of ionic species without useless time and performing high-sensitive MS/MS spectrometry, lengthens a period for applying a CID voltage in accordance with a mass number or characteristics of ions to be dissociated in proportion to a mass-to-charge ratio of ions to be dissociated to thereby optimize the application period of the supplementary AC voltage applied in superposition manner in order to dissociate specific ionic species, so that ions to be dissociated are dissociated efficiently and high-sensitive analysis of dissociated ions can be attained without useless time.

Ion trap mass spectrometer and spectrometry

A nebulized jet from a nebulizer is subjected to mechanical agitation and stirring to render the mists uniform and fine, then the droplets of the mists thus rendered uniform and fine are ionized. By accelerative collision of the resulting ions in a medium pressure chamber it is made possible to effect desolvation efficiently. Consequently, chemical noises caused by cluster ions can be greatly diminished and it is possible to attain high sensitive measurement of a sample in atmospheric pressure ionizations LC/MS.

Method and apparatus for direct coupling of liquid chromatograph and mass spectrometer, liquid chromatography&mdash;mass spectrometry, and liquid chromatograph mass spectrometer

Method and apparatus for direct coupling of liquid chromatograph and mass spectrometer, liquid chromatography-mass spectrometry, and liquid chromatograph-mass spectrometer

Disclosed is an ion trap mass spectrometer improved to obtain a high sensitivity without the lowering of resolution. By fitting a mesh electrode to an aperture (an ion sampling aperture or an ion extracting aperture) made in endcap electrodes constituting an ion trap mass analysis region, a radio frequency electric field in the mass analysis region is not disturbed even if the diameter of the aperture is set to a large value to heighten ion transmission efficiency. By fitting a shield electrode for preventing collision of ions with an insulated ring constituting an outer wall of the mass analysis region, charging up of the insulated ring is prevented to improve stability of detection signals. Furthermore, by arranging a shield member for shielding stray charged particles detouring through the circumference of the mass analysis region to approach an ion detector, generation of noises based on these stray charged particles is prevented.

Ion trap mass spectrometer

A method in which cutting of small droplets, neutral particles or photons through to a slit provided between a differential pumping portion and a mass analysis portion is combined with slight deflection of ions just before introduction of the ions into the mass analysis portion so that noises are greatly reduced without reduction of signals to thereby improve the signal-to-noise ratio which is an index of detecting sensitivity or lower limit.

Method and apparatus for ionizing a sample under atmospheric pressure

A mass analyzer comprising a sample preparation mechanism for preliminarily preparing an analyzing sample, an interface mechanism for preparing the sample into ions after the required preliminary preparation, an ion trapping part and analyzing part for analyzing the ions, and a controller. The ion trapping part and analyzing part is placed in a box portion of the body, while the interface mechanism is arranged on the front top of the box portion of the body. When the cover at the front top is removed, the front, top and right side of the interface mechanism are opened.

Mass analyzer

Method and apparatus for direct coupling of liquid chromatograph and

An eluant is supplied to an analyzer column, a sample solution is supplied through a sample inlet. The analyzer column separates the components of the sample solution. The separated components are eluted by the analyzer column, the eluted components are detected by an eluted component detector, the results of detection provided by the eluted component detector is processed by a data processor to produce a liquid chromatogram having peaks indicating the components of the sample. The components of the sample is supplied through a capillary pipe to an ion source and the ion source ionizes the components of the sample. A mass spectrometer subjects the ions produced by the ion source to mass analysis, an ion detector detects the ions included in a mass spectrum to produce an ion chromatogram having peaks. A time difference between the chromatograms is determined beforehand through an experiment using a standard sample, and the liquid chromatogram is shifted on its time axis by the time difference.

Liquid chromatograph mass spectrometry and liquid chromatograph mass

In a three dimensional quadrupole mass spectrometry, ions created in an ion source 1 are introduced into a three dimensional quadrupole field 7 formed in an ion introduction space and trapped therein. When one or more parameters of the three dimensional quadrupole field is scanned, the ions of which oscillation are instablized are successively discharged to the outside thereof and are detected by a detector 12. The signal representing the detected ions is processed by a data processing unit 13 to determine mass spectrum thereof. Prior to the above mass spectrometry, a preliminary measurement for the created ions is performed by detecting the ions passing through the ion introduction space as they are with no influences therefrom within a predetermined period by the detector 12 and a time interval during which the created ions are to be introduced into the ion introduction space for the mass spectrometry is determined based on the detected ion amount in the preliminary measurement. Thereby, the measurement time by the three dimensional quadrupole mass spectrometry is shortened while preventing ion saturation and space charge caused by the ions.

Three dimensional quadrupole mass spectrometry and mass spectrometer

An LC-MS is provided with a plurality of ion sources which can be quickly and selectively disposed at a fixed working position, and capable of analyzing a large variety of substances. An APCI unit (1) and an ESI unit (2) are fixedly mounted on a rotating table (11) or a sliding carriage (19). The rotating table (11) is held for rotation on a base (13) with a holding ring (12), and the sliding carriage (19) is held for linear sliding movement on a bearing (22) on a base (21) with a holding member (20) and is moved by a feed screw (23). Either the APCI unit (1) or the ESI unit (2) is selectively disposed at a fixed working position opposite to a first aperture (16), a second aperture (17) and a mass spectrometric unit (18) to ionize a substance for mass spectrometry. The plurality of ion sources can be set at the fixed working position by a simple setting operation, increases the variety of substances which can be analyzed, and enables the LC-MS to produce a plurality of mass spectra for a single substance to facilitate the analysis and the like of the molecular structure of the substance.

Automatic ionization mass spectrometer with a plurality of atmospheric

Method and apparatus for mass analysis of solution sample

A mass spectrometry apparatus which includes an ion source which ionizes a sample under atmospheric pressure and outputs the ionized sample, a differential pumping region, provided with apertures, for receiving under vacuum ions in the ionized sample from the ion source and outputting the ions and an ion accelerating and focusing region, having a plurality of ion accelerating electrodes each having applied thereto a voltage, for accelerating and focusing under vacuum the ions from the differential pumping region. The ions from the accelerating and focusing region are introduced under vacuum to a mass spectrometer which detects and analyzes the ions.

Growing community of inventors

Hitachinaka, Japan

Tadao Mimura