Shimadzu Corporation

Hideaki Izumi

Hiroyuki Miura

Osamu Furuhashi

Kiyoshi Ogawa

Shinichi Yamaguchi

Shigeki Kajihara

Kengo Takeshita

Akiko Imazu

Yusuke Tateishi

A mass spectrometerincludes a vacuum containerdivided into a first chambercontaining an ion trapand a second chambercontaining a time-of-flight mass spectrometer. The ion trapis held within an ion-trap-holding spacesurrounded by a wall. In this wall, a cooling-gas discharge portis formed in addition to an introduction-side ion passage portand an ejection-side ion passage port. A cooling gas supplied into an ion-capturing spaceof the ion trapis discharged from the ion-trap-holding spacethrough the three ports. The provision of the cooling-gas discharge portreduces the amount of cooling gas flowing into the ejection-side ion passage portand interfering with the ejection of ions from the ion trapinto the time-of-flight mass spectrometer. Consequently, the detection intensity of the ions is improved.

Mass spectrometer

Provided is a time-of-flight mass spectrometer including: a loop-orbit defining electrode () including an outer electrode () and inner electrode () located on the outside and inside of a loop orbit, respectively; an ion inlet (); an ion outlet () provided in either the outer or inner electrode; a loop-flight voltage applier () configured to apply loop-flight voltages to the outer and inner electrodes, respectively; a set of deflecting electrodes () facing each other across a section of an n-th loop orbit, where n is a predetermined number, the deflecting electrodes including a first portion () which faces the n-th loop orbit and a second portion () which includes other portions; and a voltage applier () configured to apply deflecting voltages to the first portion so as to reverse the drifting direction of the ions flying in the n-th loop orbit, and a voltage to the second portion so as to create the loop-flight electric field.

Time-of-flight mass spectrometer

Provided is a method for mass spectrometry in which ions to be analyzed are made to come in contact with a cooling gas in a cooling section, such as an ion trap, configured to perform the cooling of ions, and kinetic energy is subsequently imparted to the ions so as to introduce the ions into a flight space of a multi-turn time-of-flight mass separatoror similar device for separating ions according to their mass-to-charge ratios. According to the present invention, when a known or estimated number of charges of an ion to be analyzed is high, the amount of supply of the cooling gas to the cooling section is set to a lower level than when the number of charges is low. This operation improves the detection sensitivity for ions having large molecular weights and high numbers of charges.

Method for mass spectrometry and mass spectrometer

To improve the reliability of mutual diagnosis in a cancer determination by machine learning, m/z values of ions originating from tumor markers or similar substances used in other related tests are stored in a particular m/z-value database. A spectrum information filtering section deletes signal intensities at the m/z values stored in the particular m/z-value database from a large number of mass spectra classified by the presence or absence of cancer. Using the data which remain after the deletion as training data, a training processor obtains training-result information and stores it in a training result database. A judgment processor similarly deletes signal intensities at the predetermined m/z values from mass spectrum data obtained for a target sample to be judged. Then, based on the training-result information stored in the training-result database, the judgment processor determines whether the target sample should be classified into a cancerous group or non-cancerous group.

Mass spectrometric data analysis device and analysis method

A time-of-flight mass spectrometer includes a flight tube, an ion introduction unit that is connected to the flight tube, an ion detector that detects an ion flown in the flight tube, and a control unit that controls the ion introduction unit and the flight tube, wherein: the control unit sequentially changes an accumulation state of the ion to be introduced into the flight tube by the ion introduction unit, for a plurality of measurement processes performed repeatedly.

Time-of-flight mass spectrometer and program

To compensate for the distortion of the loop-flight electric field with a higher level of accuracy, a multiturn time-of-flight mass spectrometerincludes: a main electrodeconfigured to generate, within a predetermined loop-flight space, a loop-flight electric field which is an electric field that makes an ion fly in a loop orbit multiple times, the main electrode having an openingorthrough which ions are introduced into or extracted from the loop-flight space; a compensating-electrode attachment partmade of an insulating material and fixed to the main electrode; and a compensating electrodeconfigured to compensate for a distortion of the loop-flight electric field which occurs in the vicinity of the opening, the compensating electrode being fixed to the compensating-electrode attachment part directly or via a substrateand located in the vicinity of the opening.

Multiturn time-of-flight mass spectrometer and method for producing the same

A microchannel plate (MCP)in an ion detection sectionmultiplies electrons. An anodedetects those electrons and produces a current signal. An amplifierconverts this signal into a voltage signal. A low-pass filterA acting as a smoothing sectionis located at the output end of the amplifier. A waveform-shaping time adjusteradjusts the time constant of the low-pass filterA beforehand according to the response time of the MCP, mass-to-charge ratio of an ion species to be subjected to the measurement, and duration of the spread of the ion species which depends on device-specific parameters. A plurality of peaks which sequentially appear in the detection signal corresponding to one ion species are thereby smoothed into a single broad peak. Thus, the distinguishability between signal waves and noise components is improved.

Ion analyzer

A gate electrode (A) used as a shutter gate includes a pair of conductive fixture members () made of metal and identical in size attached to the inside of a rectangular opening () of a ceramic base (), along with insulating fixture members () made of ceramic attached to the inner sides of the conductive fixture members. Two comb electrodes () as one pair have connecting portions () adhered to the conductive fixture members () as well as thin-wire electrodes whose distal ends are adhered to the insulating fixture members (). By setting length L of the opening () and width D of the conductive fixture members () to appropriate values according to the coefficient of thermal expansion of each of those members, the elongation of the electrodes which accompanies an increase in temperature can be balanced by the increase in the distance between the adhered positions of the electrodes to prevent the electrodes from being excessively taut or slack. Therefore, the drift region can be heated to a higher temperature than conventional levels to perform a high-accuracy, high-resolution analysis free from the influence of residual water vapor or similar particles.

Gate electrode and ion mobility spectrometer

Used as an ion beam guiding unit for introducing primary ions to the surface of the sample is an ion optical system of reflectron TOFMS for achieving time focusing including an orthogonal acceleration unit for accelerating the ions in the orthogonal direction, a flight space of a non-electric field, and an ion reflector for forming a reflecting electric field. A dual stage type is used as the ion reflector to superimpose the correction potential showing a predetermined non-linear potential distribution on the potential having a linear gradient of a uniform electric field at the side deeper than the second order focusing position that fulfills the Mamyrin solution, thereby correcting the temporal spread of ion packets emitted from the orthogonal acceleration unit until the deviation of third or higher order in energy, achieving high time focusing.

Ion radiation device and surface analyzer using said device

A first mass analysis is executed in a condition that gas is not introduced into a loop-flight chamber (), and a time-of-flight spectrum obtained in a data processor () is stored in a storage unit (). Next, a second mass analysis is executed on the same sample as the one used in the first mass analysis in a condition that a valve () is opened and helium gas (He) is introduced into the loop-flight chamber (), and the time-of-flight spectrum is obtained in the data processor (). If different kinds of ions having the same m/z value exit, these ions form a single peak in the first time-of-flight spectrum, while these ions appear as separate peaks in the second time-of-flight spectrum even though they have the same m/z value. This is because, in the second mass analysis, the ions collide with the gas and have different times of flight depending on their difference in size. A spectrum comparator () judges a change in the position or shape of the peak by comparing the two spectra, and outputs information relating to the difference in the size of the ions (the molecular structure, charge state, or molecular class of the ions), and the like. Accordingly, a wider variety of information than ever before can be provided.

Time-of-flight mass spectrometer for conducting high resolution mass analysis

In an ion detector, power supplies (through) generating independently controllable voltages are provided to respectively apply voltages to first to fifth dynodes (through), a final dynode (), and an anode () in a secondary electron multiplier (). Furthermore, the signal from the anode () is extracted, and the signal from the fifth dynode (), which has a low electron multiplication rate, is extracted. These two signals are concurrently converted into digital values, taken in by a data processing unit (), and stored in a data storage unit (). When a mass spectrum is created in the data processing unit (), the two detected data for the same time are read out and the presence or absence of signal saturation or waveform deformation is determined from the values of one of the detection data. If there is a high probability of signal saturation, the detection data based on the signals in the intermediate stages are selected, and the level of the selected data is corrected. The application of independent voltages to the secondary electron multiplier () makes the signal saturation less likely to occur. Even if saturation temporarily occurs, an unsaturated signal can be reflected in the mass spectrum.

The main voltage generator () applies a rectangular-wave radio-frequency voltage to the ring electrode () in order to capture ions inside the ion trap (). In the case where the TOFMS () is operated in the reflectron mode, the radio-frequency voltage is changed into a constant voltage value when the phase thereof is 1.5&#x3c0;, and a voltage for expelling ions is applied to the end cap electrodes () to expel the ions from the exit aperture () and introduce them into the TOFMS (). In this case, since the velocity spread of the ions inside the ion trap () 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 () is operated in the linear mode, the radio-frequency voltage is changed into a constant voltage value when the phase thereof is 0.5&#x3c0;, and then the ions are expelled. In this case, a high mass resolution and mass accuracy can be achieved since the variation of the ions' acceleration, which cannot be converged in the linear mode, can be suppressed.

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Kyoto, Japan

Hideaki Izumi