SU1307493A1 - Method of analyzing ions in ion-trap-type hyperboloid mass spectrometer - Google Patents

Abstract

The invention relates to the field of dynamic mass spectrometry and can be used in the development of hyperboloid mass spectrometers such as ion traps with high resolution and sensitivity. The aim of the invention is to increase the resolution and sensitivity of a given mass spectrometer, as well as to expand its functionality. The essence of the method is the simultaneous analysis and sorting of charged particles in a high-frequency electric field and a laser radiation polo. The device implementing the method consists of an electronic source 1, an analyzer formed by ring 2 and two end electrodes 3, an ion collector 4, an ion detector 5, a control unit 7 of a high-frequency generator 6, a synchronization device 8, a control unit 9, a photon detector 10 11 and 12 laser radiation, photon acquisition and collimation systems 13. The holes 14 are made in the ring electrodes, and the holes 15 in the end electrodes. The method allows a sharp increase in the resolution of mass spectrometers of this type over a number of scenarios with high sensitivity analysis, to use them to study the features of nonlinear selective interaction of ions with laser radiation. 1 znf-ly. 1 il. i (Л С оо 4 СО со

Description

The invention relates to;, iamic .iacc-ciieKTj) OMeTpHHn can be used in the development of ionomer-based mass spectrometers such as ionic; high resolution and sensitivity.

The aim of the invention is to increase the efficiency and sensitivity of the gynerboloid mass spectrometer of the three-dimensional ion trap, as well as to expand its functionality.

Analysis of ions in a hyperboloid. Mass spectrometer by specific charges, concluded in the introduction into the working volume of the analyzer of the investigated ions, sorting them out by specific charges in a high-frequency field, outputting to the measuring device and determining their number, is dried by the introduction of laser radiation into the working volume of the analyzer and their selective influence on the sorting ions.

In this case, the selective effect of laser radiation on complex molecular ions is accomplished by dissociating them, for example, through processes involving H1, two-step or photooptical mechapisms.

At the same time, for 1dissociated molecules of p1 of x ions, the value of the specific charge is significantly changed, and they are removed from the working volume of the analyzer. For this method, laser radiation is introduced into the working volume of the analyzer impulsively, and determination of the number of ions with selected specific charge is carried out by the ratio (or difference) of output signals corresponding to the presence and absence of laser radiation.

Pzbn) athe.: 1 The effect of laser radiation on P1 on simple (atomic) ions with selected Niii M el1) 1m charge is realized by selective excitation of ions, found in nm xc in the sorting process in the working volume ana. the lysator, and determine their number but measuring the number of photons by fluorescent energy, measured by ions under the action of laser radiation 1u.

The sundown of the proposed method of analysis consists in the simultaneous analysis and sorting of charged particles in a high-frequency electric field in no. i.e. laser radiation.

When using selective dissociation of molecular ions to increase the mass spectrometer, the discriminating ability of the mass spectrometer selectively affects only those ions that are difficult to separate in the high-frequency field, double the ions of the doublets. In this case, the mode is used, the magnitude of the field in the high-frequency field, but high sensitivity, and the mode of high detentions on selective exposure to laser radiation. Thus, a sensitive, high-dilution high sensitivity gp is detected. With this laser

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My radiation is injected into a pulse and the presence of a component is determined by the deviation of the output signals corresponding to the presence and absence of radiation and the known degree of dissociation of molecular ions. Under laser frequency tuning conditions, such a method without mass spectrometric separation of duplexes makes it possible to determine their intensity.

When using selective fluorescence analysis of simple ions sorted in a hyperboloid. M analyzer, their number is determined by the number of photons of fluorescence. This method of determining the number of simple ions is one of the most sensitive. Thus, in this case, parallel analysis of the composition of ions makes it possible to increase the sensitivity and resolution of the analysis being performed.

To increase the efficiency () of the interaction of laser radiation with ions, it is necessary to use the input of laser radiation along the asymptotes of the hyperbolic system (oid electrodes, because, in this case, you succeed without degrading the electrical configuration); 1 This means that the channels for the input and output of laser radiation can be performed outside the working surfaces of the analyzer and therefore make them sufficiently large (.mm) and eliminate the diaphragm of the laser radiation. students

Thus, in this method of analysis, it is possible to maintain high analytical parameters for sorting ions in high-frequency fields and to achieve high efficiency in delivering laser radiation to the ions being sorted, with a negligible background of scattered radiation from the metal surface of the analyzer electrode system, which is extremely important increase the sensitivity of the fluorescence detection method. At the same time, the operation of the analyzer and the laser must be synchronized through the control unit of the high-frequency generator with the help of a standard synchronizing unit.

When using ion-fluorescence analysis, the fluorescence photon counting channel should also be synchronized with the operation of the high-frequency generator. In this case, the signal-to-noise ratio can be improved and the sensitivity of the analysis increased.

The drawing illustrates the proposed analysis method and device for its implementation.

The proposed device consists of an electronic source 1, an analyzer formed by annular 2 and two end electrodes 3 electrically connected, an electron collector 4, an ion detector 5, B1) 1 frequency generator 6, the output of which is connected to the analyzer electrodes, control unit 7 of a high frequency generator The outputs of which are connected to the electronic source 1, the ion detector 5, the input of the high-frequency generator 6, the input of the synchronizing device 8 and the input of the control unit 9, the detector of 10 photons, siphro iziruyui1.ego devices 8, the outputs of which are connected with the blocks 11 and trigger source 12 of laser radiation collection system 13 and the collimation of the fluorescence photons, the detector 10 of photons, which is controlled by the control unit 9, whose output is connected to the detector 10 of photons. Holes are made in the ring electrodes

14, and in the end electrodes - holes

15. Channels 16 are made at the electrodes 2. The optical matching system is indicated by 17.

The operation of the device implementing the method for analyzing ions by specific charges in a hyperboloid mass spectrometer is carried out as follows.

The input of the analyzed ions into the working volume of the analyzer of the three-dimensional trap type is depleted by ionizing the atoms or gas molecules by the electron flow formed by the electronic source 1. The ionizing electron flow, the passage through the holes 14 of the ring electrode 2, is captured by the collector 4. The ions formed as a result of ionization are sorted into the volume of the analyzer bounded by an annular electrode 2 and end electrodes 3, connected electrically, in a high-frequency field, arising due to the delivery to these electric ktrody in. with a constant voltage component of the high-frequency generator 6, from which the electronic source and the ion detector 5 are controlled via control unit 7 c. h. generator The sorted ions are led toward the detector 5 ions through holes 15, made in the end electrodes.

During the sorting of ions into the working volume of the analyzer, through the channels 16, laser radiation is introduced (and outputted) and selectively affects the particles to be sorted. Radiation is introduced through the optical matching system 17 of the excitation units 11 and 12, whose operation is controlled by the synchronization unit 8, the input of which is connected to the output of the control unit 7. generator 6 for matching the input time of the radiation with the phases of the operating cycle of the mass spectrometer, and the output is connected to the laser start input. Laser radiation is introduced along the asymptotes of the analyzer electrode system.

Having tuned the laser radiation to the absorption line of a certain type of ions held by the analyzer, they are detected by either the photodissociation or the fluorescence method. When selective fluorescence is detected, the resulting photons pass through the holes 15 in the end electrode 3, are collected and

are collimated by system 13 and captured by a 10 photon detector, whose operation is controlled by control unit 9, an output that is connected to a 10 photon detector, and an input to control unit 7. generator hours 6.

For example, to separate dunlet 28 a. e. m. (CO and N2) you can use the fluorescence method of analysis. For this, it is necessary to excite either nitrogen ions N2 at wavelength /. 392.7 nm, or CO + ions at a wavelength of A. 482.3 nm emitted by a dye laser pumped by an N2 laser (on a 337 nm). When the pulse power of the Dye laser is P-SCHOKW and the duration of the generation pulse 10, not all nitrogen ions (or CO +) will fluoresce and by the number of photons emitted by them during the laser radiation, one can judge their number. Estimated Resolution

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- 7 6000. At the same time feel / Mso PMG /

The analysis is higher due to the fluorescence method of recording the number of ions retained.

To separate the doublet 118 a. E. m. (CCl3 and FC1O4) you can use the photodissociation method of analysis. For this, it is necessary to produce a multiphoton dissociation of the molecular ion CClI in the powerful IR radiation field of the TEA CO2 laser, tuned to the frequency of absorption of the CC1 ion.)

Ez 1037, lying in the range of frequencies generated by CO2 laser.

The required parameters of CO2 laser radiation are the following: pulsed power P = 1 MW, duration of generation pulses 100-500 NS. The number of molecular ions CC1 3 can be determined by comparing the number of ions retained without and in the presence of laser radiation, meaning the degree of multiphoton dissociation. The resolution in this case reaches the values of p 1500, and the sensitivity increases by an order of magnitude due to the use of the operation of the hyperboloid mass spectrometer in the low resolution mode and high sensitivity.

Thus, the use of the proposed method and device for its implementation allows a sharp (as can be seen from the above calculations up to 6000) increase in the resolution of the ability of hyperboloid mass spectrometers on a number of substances with high sensitivity of the analysis; expand the possibilities of using hyperboloid mass spectrometers to study the features of nonlinear selective interaction

ions with laser radiation; to expand the possibilities of using analyzers of hyperboloid mass spectrometers to study the dissociation of molecules with the formation of ions and the influence of high-power laser radiation on these processes.

Claims (2)

1. A method of analyzing ions in a hyperboloid mass spectrometer of the ion trap type, according to which the analyzed ions in the working volume of the analyzer are sorted by specific charges in high-frequency the field is derived from the analyzer volume and is detected, characterized in that, in order to increase the sensitivity and resolution, the ions being sorted selectively act with laser radiation and measure the ratio of output signals corresponding to the presence and absence of laser radiation, or measure the number of fluorescence photons . 2. The method according to claim 1, characterized in that laser radiation is introduced into the analyzer volume according to the asymptotes of the electrode system.