Method and device for predicting interference in mass spectrometry

Abstract

Provided is a method for predicting spectral interference in a mass spectrometry method employing an inductively coupled plasma mass spectrometry device. According to the present invention: a mass spectrometry method and an associated response coefficient are selected from a database in which a plurality of mass spectrometry methods each defining a mass spectrometry condition and a response coefficient indicating a correlation between an element and the signal strength of the element for each mass spectrometry method are stored; an application is selected from an application library in which applications specifying the types and contents of elements are collected; signal strengths indicating each element specified in the selected application and a signal strength indicating an interference component for each element are estimated; and spectral interference predicted for each element is displayed.

Description

Method and apparatus for predicting interferences in mass spectrometry

[0001] The present invention relates to ICP-MS (inductively coupled plasma mass spectrometry), and more particularly to a method and apparatus that can evaluate the effect of interferences on mass spectrometry methods that can be performed in ICP-MS without actually performing measurements. The method of the present invention can be executed according to a computer program, and this computer program can be implemented in an ICP-MS device.

[0002] ICP-MS is useful for analyzing inorganic elements, especially trace amounts of metals, and is widely used in many fields, including the semiconductor, geological, and environmental industries. ICP-MS allows for virtually simultaneous multi-element analysis of most elements in the periodic table, and quantification of element concentrations at excellent sensitivity levels of parts per billion (ppb) or parts per trillion (ppt).

[0003] ICP-MS uses an atmospheric-pressure inductively coupled argon plasma as an ionization source. Ions of the analyte elements generated in the plasma are introduced as a beam by a differential pumping system into a high-vacuum mass spectrometer, where they are separated and measured according to their mass-to-charge ratio (m / z). In one example, the analyte elements are dissolved in a sample solution and pumped, along with an element added as an internal standard, into a nebulizer that generates a sample aerosol. The sample aerosol is fed into the plasma, where it is desolvated, atomized, and ionized. The resulting element ions are transported from the atmospheric-pressure plasma to the mass spectrometer through an interface with two orifices, known as the sampling cone and skimmer cone, and an ion lens.

[0004] Because of the above configuration, when detecting the weak signal of the target element, ICP-MS instruments can suffer from spectral interference from argon and other coexisting elements that make up the plasma, resulting in a decrease in signal intensity. Spectral interference occurs when components from other sources overlap with the mass of the target element. Various spectral interferences, such as isobaric interference, polyatomic ion interference, and divalent ion interference, can affect the accuracy of analytical results. Therefore, it is necessary to reduce or eliminate interferences using appropriate methods to ensure the reliability of quantitative values.

[0005] In order to eliminate the effects of spectral interference, a collision / reaction cell is often placed after the ion lens in ICP-MS devices. The collision / reaction cell introduces a reactive gas with a relatively small molecular weight, such as hydrogen, or an inert gas, such as helium, to selectively neutralize polyatomic ions in the introduced ion beam by causing them to react with the gas molecules, or to cause them to lose kinetic energy through collisions, thereby preventing interference with the measurement signal. In some cases, devices are also used in which mass spectrometers are placed in tandem before and after the collision / reaction cell in order to more selectively remove spectral interference. Summary of the Invention

[0006] To actually perform measurements using an ICP-MS device, it is necessary to create an analytical method suited to the sample by predicting interfering components for each individual sample, selecting the internal standard element to be used, setting plasma conditions, gas conditions for the collision / reaction cell, integration time for the mass spectrometer, etc. If the measurement results are not satisfactory, it is necessary to repeat the measurements to find better measurement conditions and optimize the method, but this is a time-consuming and laborious task.

[0007] Japanese Patent Laid-Open No. 2010-169412 discloses a method for identifying major component elements by semi-quantitative analysis using a basic database based on spectral data from ICP optical emission spectroscopy, extracting information related to the major component elements from an interference database to modify the basic database, calculating the amount of interference in a measurement of a sample at a predetermined measurement wavelength using the modified basic database, and displaying the amount of interference at the measurement wavelength and the lower limit of quantitation. This method involves analyzing optical emission spectral data obtained by actually measuring a sample, and does not disclose anything about evaluation without actually measuring it.

[0008] Japanese Patent Laid-Open Publication No. 2008-45901 describes a technology in which conditions such as carrier gas flow rate in an aerosol and plasma RF power are automatically determined by a computer program using the correlation between the sensitivity of a specific metal ion and its oxide ion. This technology is particularly suitable for optimizing plasma conditions to avoid interference in response to high-matrix samples, but does not evaluate in advance the interferences expected in the measurement.

[0009] The present invention aims to provide an evaluation of the reliability of quantitative results obtained by a mass spectrometry method that can be performed by ICP-MS by estimating in advance the spectral interferences in the mass spectrometry method and the extent to which the spectral interferences contribute to the signal intensity of the expected measured sample, without actually performing measurements. Another aim of the present invention is to provide the evaluation thus obtained in an easy-to-understand format to the user, and further to provide information on the content / details of the evaluation as needed.

[0010] According to one embodiment of the present invention, there is provided a method for predicting spectral interferences in a mass analysis method used in an inductively coupled plasma mass spectrometer, the method comprising: selecting a mass analysis method and an associated response factor from a database storing a plurality of mass analysis methods, each of which defines mass analysis conditions, and a response factor indicating the correlation between elements and the signal intensity of each element for each mass analysis method; selecting an application from an application library that collects applications that define the type and content of elements; estimating the signal intensity indicating each element and the signal intensity indicating an interfering component for each element, as defined in the selected application; and displaying the predicted spectral interference for each element.

[0011] As described above, in order to actually perform measurements using an ICP-MS instrument, an analytical method must be created by setting various conditions. However, the present invention makes it possible to predict the type of spectral interference that will occur when a created mass analysis method is performed using an inductively coupled plasma mass spectrometer, without actually performing measurements. A database stored in a memory or hard disk contains multiple mass analysis methods and their corresponding response factors. Each mass analysis method can specify mass analysis conditions, including at least one of plasma conditions, cell conditions, and sample introduction conditions, and may also specify other conditions, such as sample uptake time, internal standard element, mass-to-charge ratio used in the mass spectrometer, and integration time.

[0012] Plasma conditions can include RF power conditions, sampling depth (i.e., the relative positions of the load coil and sampling cone), flow rate of injector gas including nebulizer gas, makeup gas, and dilution / optional gas, type of injector gas (usually argon but oxygen added for organic samples, helium gas considered for laser ablation), and / or wet / dry conditions (GC-ICP-MS or LA-ICP-MS).

[0013] The cell conditions, i.e., the conditions related to the collision / reaction cell, include whether or not a cell gas is used, the type of cell gas (He, H２ , O ２ , 10% NH ３ / He, CH ４ , and mixtures thereof), and / or interference reduction mechanisms (KED or kinetic energy discrimination, CID or collision induced dissociation, and / or reactions).

[0014] Each mass analysis method individually defines the mass analysis conditions as described above, and the database stores response factors that indicate the correlation between elements and their signal intensities for each mass analysis method. That is, when a user selects a mass analysis method, a corresponding set of response factors is selected. However, the response factors may be modified depending on the configuration of the inductively coupled plasma mass spectrometer, for example, whether the mass spectrometer is a single quadrupole or triple quadrupole, the design of the interface and ion optical system, etc.

[0015] The application library can consist of a collection of applications for different matrices, such as a drinking water application, a seawater application, and a sediment / soil extract application, each of which specifies the type and content of elements. The user selects the desired application from the library. This application library can also be stored as a database in memory or on a hard disk. Applications can also be added or the contents of existing applications can be modified as desired.

[0016] When a user selects a mass spectrometry method, a response factor specified for the method, and an application, the signal intensities of each element and interference components for each element specified in the selected application are estimated. The user can select the method via an input interface, such as a keyboard or mouse. The signal intensities of interference components can be estimated based on previously obtained interference ion information regarding the mass numbers and production rates of compound ions and multiply charged ions produced during ionization of each element. The interference ion information provides estimated signal intensities of interference components for each of the plasma conditions corresponding to the mass spectrometry method and the cell conditions used in the collision / reaction cell. This information can be stored in a database like other data. The signal intensities of each element can be determined by scanning the range of mass numbers of elements included in the application, multiplying the element concentration specified in the library by a response factor, and taking into account the abundance ratio of the isotopes.

[0017] The signal intensity indicating interference components can be estimated for each element specified in the application by referring to the type and generation rate of interference ions, the type and isotope ratio of isobars, and other factors. Possible interference components include isobars of other elements, polyatomic (molecular) ions resulting from other elements, and multivalent ions of other elements. Ions that interfere with singly charged ions (M+) of each mass number are typically known to include species such as M++, MO+, MH+, MAr+, MM+, and MOH+. The generation ratio of these interference ions can be obtained by calculating the ratio between the signal of a sample with a known concentration and the signal of the interference ions generated by the sample. In one embodiment, a list of the type and generation rate of interference ions and each element can be created in advance and stored as a table in computer memory for reference. Because the generation rate of interference ions can vary depending on mass analysis conditions, multiple tables showing the generation rate of interference ions can be prepared depending on plasma conditions, cell gas conditions, etc. The signal intensity of each interference ion can be estimated by multiplying the element concentration included in the application by the generation rate of the interference ion.

[0018] Furthermore, since the type of isobars and their isotopic ratios are known for each element of mass number, the signal intensities of the isobars can be estimated by multiplying the isobaric elements by the isotopic ratios. In this way, the signal intensities representing the elements and the signal intensities representing the interference components for each element can be estimated, and the predicted spectral interference for each element can be displayed based on this.

[0019] The predicted spectral interferences may be displayed as interference levels, represented by the signal intensities of each element versus the signal intensities of the components interfering with each element, and may be displayed in other formats, such as percentages, star ratings, and / or heat maps, allowing the user to understand the impact of interferences at a glance.

[0020] The display of predicted spectral interferences may be displayed together with an image of the periodic table, for example, with a heat map or coloring applied to each element in the periodic table to provide a visual and intuitive understanding of the effects of the interferences.

[0021] According to another embodiment of the present invention, a computer program for predicting spectral interferences in a mass analysis method used with an inductively coupled plasma mass spectrometer is provided. In one embodiment, the computer program causes a computer to execute the following steps: select a mass analysis method and an associated response factor from a database storing multiple mass analysis methods, each of which defines mass analysis conditions, and a response factor indicating the correlation between elements and their signal intensities for each mass analysis method; select an application from an application library containing applications that define the type and content of elements; estimate the signal intensities indicating each element and the signal intensities indicating interference components for each element specified in the selected application; and display the predicted spectral interferences for each element. The estimating means may estimate the signal intensities indicating interference components based on a table storing previously obtained interference ion information regarding the mass numbers and production rates of compound ions and multiply charged ions produced during ionization of each element. The program may further include a step of correcting the response factor depending on the configuration of the inductively coupled plasma mass spectrometer.

[0022] The computer program may be supplied as a downloadable program from a storage medium or a network, or may be executed from a network without being downloaded. The computer program may also be installed in an ICP-MS instrument and used for actual measurements after evaluating a mass spectrometry method.

[0023] In its device aspect, the present invention can be an apparatus for predicting spectral interferences in a mass spectrometry method used in an inductively coupled plasma mass spectrometer, which can be operatively connected to the inductively coupled plasma mass spectrometer, i.e., the apparatus is operatively connected in association with the inductively coupled plasma mass spectrometer, and can be either built into the inductively coupled plasma mass spectrometer itself or externally connected.

[0024] In one embodiment, the above-described apparatus includes a plurality of mass analysis methods, each of which defines the mass analysis conditions; a database storing response factors indicating the correlation between elements and their signal intensities for each mass analysis method; and an application library containing applications specifying the type and content of elements. The apparatus may include a processor such as a CPU, which is capable of selecting a mass analysis method and associated response factors from the database, selecting an application from the application library, and estimating the signal intensities indicating each element and interference components specified in the selected application. This allows spectral interferences for each element to be predicted and displayed on a display. The processor may further be capable of correcting the response factors depending on the configuration of the inductively coupled plasma mass spectrometer.

[0025] According to the present invention, users can evaluate the influence of interferences on existing or desired mass spectrometry methods in a given or desired application without actually performing measurements. Based on this evaluation, users can improve the mass spectrometry method by changing, for example, plasma conditions or collision / reaction cell tuning conditions. This saves time required to create mass spectrometry methods for ICP-MS, while also leading to the development of methods that can obtain reliable results, thereby improving the analytical accuracy and reliability of quantitative results.

[0026] FIG. 1 is an explanatory diagram showing an example of an apparatus capable of performing mass spectrometry contemplated by the prediction method of the present invention. FIG. 2 is a flowchart showing an exemplary algorithm according to one embodiment of the present invention. FIG. 3 is a graph showing exemplary response factors that can be used in the present invention, illustrating example response factors in helium gas mode and high-sensitivity plasma conditions. FIG. 4 is a table showing exemplary applications that can be used in the present invention. FIG. 5 is a flowchart showing an algorithm according to one embodiment of the present invention for estimating spectral interferences. FIG. 6 is an example display of prediction results shown in association with an image of the periodic table. FIG. 7 is another example display of prediction results shown in association with an image of the periodic table. FIG. 8 is another example display of prediction results shown in association with an image of the periodic table. FIG. 9 is a table showing an exemplary relationship between interference level and reliability.

[0027] 1 is an explanatory diagram showing an example of a mass spectrometer capable of performing mass analysis assumed in the prediction method according to the present invention. When the present invention is implemented, measurements are not actually performed using such an apparatus, but when a useful mass analysis method is finally obtained, actual measurements may be performed using such an apparatus.

[0028] The ICP mass spectrometer 100 shown in FIG. 1 includes an inductively coupled plasma ion source 130, an interface 140 that extracts elemental ions generated from a sample from the plasma, an ion lens 150 that accelerates the extracted ions and sends them out as an ion beam, a collision / reaction cell 160 located behind the ion lens, and a mass filter 170 and a detector 180 for separating the elemental ions based on mass.

[0029] In the sample collection unit 110, a sample 112 in a vial is sucked up by a peristaltic pump 111 and sent into a nebulizer 121 protruding from the end of a temperature-controlled spray chamber 122 provided in the sample introduction unit 120. The sample collection unit 110 can be equipped with multiple vials, each containing a sample to be measured, various standard solutions, tuning solutions, calibration solutions, rinse solutions, etc., and can be automatically switched between them. The nebulizer 121 forms a sample aerosol by atomizing it using high-pressure argon (Ar) gas. This aerosol passes through the spray chamber 122, where large droplets are removed, and is then blown into the ion source 130.

[0030] The ion source 130 comprises an ICP torch 131, which consists of a series of concentric quartz tubes through which Ar gas flows, and which are positioned inside a radio frequency (RF) coil 132. The RF magnetic field produced by the coil excites Ar atoms passing through the torch, enabling a high-energy plasma to be created and sustained. The sample aerosol is injected into the plasma, where it is desolvated, atomized, and ionized.

[0031] In the interface 140, ions are extracted from the plasma through a sampling cone 141 and a skimmer cone 142, accelerated by an ion lens 150, and sent as an ion beam into a subsequent collision / reaction cell 160. The ion lens 150 may include an extraction electrode 151, a series of focusing lenses 152, and an omega lens 153 mounted off-axis. Gases can be introduced into the collision / reaction cell 160, as indicated by 161. Such cells are well known, and remove polyatomic ions from the introduced ion beam, including elements derived from the carrier gas, plasma gas, and auxiliary gas, that may interfere with the mass spectrum, by causing charge transfer reactions due to collisions with gas molecules, a reduction in kinetic energy, etc. The cell 160 may also include a multipole electrode, such as a quadrupole mass filter 162.

[0032] Following the collision / reaction cell is a mass spectrometer, consisting of a mass filter 170 and a detector 180. The mass filter 170 illustratively comprises a quadrupole mass filter 171 made up of four parallel rods, to which radio frequency and DC voltages are applied. For any combination of applied radio frequency and DC voltages, the mass filter passes only ions of a specific mass-to-charge ratio to the detector 180. This allows the detector 180 to separate and measure ions of different elements. The detector 180 includes an electron multiplier detector 181 located immediately after the mass filter. The ion signal for each mass is amplified and then measured using a multichannel counting device. The signal strength (CPS) of an element measured over a given integration time is directly proportional to the concentration of that element in the sample solution.

[0033] The sampling section 110, sample introduction section 120, inductively coupled plasma ion source 130, collision / reaction cell 160, mass filter 170, etc. can all be controlled by a system controller of the ICP mass spectrometer, which in turn can be controlled by a computer such as a personal computer. The method of the present invention can be implemented as a program executed by this computer. A computer running such a program and an ICP mass spectrometer 100 including such a computer are also within the scope of the present invention.

[0034] That is, according to one example, the method according to the present invention can be executed as a computer program by a personal computer in Fig. 1 to predict spectral interferences in mass spectrometry methods that can be performed using the inductively coupled plasma mass spectrometer configuration shown in the figure. For example, multiple mass spectrometry methods, each specifying mass spectrometry conditions, may be stored in a database built into the personal computer or connected via wired or wireless communication, along with a response factor indicating the correlation between elements and the signal intensities of the elements for each mass spectrometry method.

[0035] The database may include an application library that contains applications that define the type and amount of elements, and may include multiple applications for different matrix elements, such as a drinking water application, a seawater application, a sediment / soil extract application, etc. The user can add or modify applications as desired.

[0036] A user selects a mass spectrometry method and associated response factors from a database and an application from an application library via an input interface to a computer (processor). The computer, according to the program, can execute a process to estimate the signal intensities indicating each element specified in the selected application and the signal intensities indicating components interfering with each element. The processing results, i.e., the predicted spectral interferences for each element, may be displayed on the display of the personal computer or on the monitor screen of the ICP-MS apparatus shown in FIG. 1.

[0037] 2 shows a basic flowchart of an algorithm according to one embodiment of the present invention. Once a mass spectrometry method and application, each with a predetermined response factor, is selected from the database, the signal intensity of each mass-to-charge ratio within a predetermined mass range is calculated based on the response factor. That is, the database stores response factors, which are correlations between signal sensitivity and elements, depending on cell gas conditions (e.g., no gas mode, helium gas mode, high-energy helium gas mode, and hydrogen gas mode), plasma conditions, and sample introduction conditions (e.g., lens configuration).

[0038] For example, low-temperature plasma has the advantages of suppressing carrier gas ionization, reducing background noise, and increasing sensitivity to light elements. However, it also has drawbacks, such as increased matrix effects in high-matrix samples and difficulty ionizing elements with high ionization potential. The response factor defines the relationship between elements and signal sensitivity, taking these conditions into account. The present invention obtains estimated values ​​for the signal of each element and the signal of interference components for each of these conditions. The example shown in Figure 3 shows the response factors under helium gas mode and high-sensitivity plasma conditions. The Y-axis represents signal strength (CPS) by concentration, and the X-axis represents atomic number.

[0039] The response factor of each element E is F ＳＱ (E), the response factor F for each isotope i [m / z] of element E ＳＱ (i) is calculated as follows: Note that all of the following calculations may be performed using well-known elements such as the processor, memory, latches, and registers mentioned above. where Abd(i,E) is the relative abundance of the isotope of the element, and the signal intensity I(i,E) of each isotope i [m / z] based on element E is calculated as follows: where C(E) is the concentration of element E, which can be loaded by the user from an application library of drinking water, seawater, sediment extract, soil extract, etc., or can be any value depending on the application. As an example, the seawater application library is shown in Figure 4.

[0040] From the above, the signal intensity I(M) for each mass-to-charge ratio M [m / z] is calculated as follows: For example, a mass-to-charge ratio of 50 m / z is composed of isotopes of titanium, vanadium, and chromium, and the signal intensity is calculated as follows:

[0041] Next, the intensity of each spectral interference for all mass numbers is calculated. Figure 5 shows a flowchart for calculating the signal intensity from the spectral interference for each mass number. Here, the signal intensity based on the spectral interference may be calculated using the intensities of a data set previously obtained for all mass numbers, and each element corresponding to the mass number can be identified based on its production rate. The production rate is defined for each element according to the state of the cell gas and plasma actually measured in advance, and the intensity of the spectral interference I ｎ (M) may be calculated as follows: Here, M source is the mass of the element that is the source of interference, and R(n) is the interference generation rate.

[0042] Interfering components may include polyatomic (molecular) ions resulting from other elements, multiply charged ions of other elements, etc. Ions that interfere with singly charged ions (M+) of each mass number are known to include species such as M++, MO+, MH+, MAr+, MM+, and MOH+. Furthermore, since the type of isobars and their isotope ratios are known for elements of each mass number, it is possible to estimate the CPS (counts per second) of the isobaric components acting as interfering components by multiplying the isobaric elements by the isotope ratio. When M [m / z] cannot be identified as an element and there are isobars, the spectral interference signals from the individual isobars can be calculated. The intensity I' (M ｉ ) may be calculated as follows: where I(M ｉ，ｊ ) is the signal intensity of an individual isobar calculated based on its isotopic abundance. E represents the set of elements that comprise that isobar; for example, a mass-to-charge ratio of 50 m / z represents the set of titanium, vanadium, and chromium.

[0043] From the above, the total intensity I of spectral interferences that may overlap with the mass-to-charge ratio M [m / z] is intfs (M) is calculated as follows: Here, I ｎ is the intensity of the individual spectral interferences. The total intensity I that is actually expected to be measured in a measurement for the mass-to-charge ratio M [m / z] meas(M) can be calculated as follows:

[0044] Next, calculate the concentrations corresponding to all mass numbers. The isotope M calculated from the reference mass number, which is the mass number representing the isotope of a certain element. ｉｓｏ The intensity of [m / z] is expressed as I(M ｉｓｏ ) M ｉｓｏ The natural isotope abundance of [m / z] is expressed as A(M ｉｓｏ ) and I(M ｂａｓｅ ) is the base mass M defined for that element ｂａｓｅ [m / z]. In this case, I(M ｉｓｏ ) is calculated as follows: where the intensity used in the calculation is the minimum count I ｍｉｎ It is necessary to exceed this.

[0045] Count the number of isotopes that satisfy the following conditions:

[0046] If the number of isotopes is 1, then the isotope M ｉｓｏ [m / z] accounts for the majority of the mass number M[m / z], and M ｉｓｏ The "element" that is the source of [m / z] is the element expected as M[m / z]. In other cases, M[m / z] cannot be identified as an element. The concentration C(M) of the mass M[m / z] that can be defined as an element is calculated as follows:

[0047] 3, the reliability of the measurement of each mass number is predicted based on possible interference. That is, based on the signal strength of the spectral interference obtained as described above, it is possible to evaluate the interference that may overlap with the signal strength of each mass number. This evaluation can be performed, for example, based on the interference level [%].

[0048] The interference level IL(M) [%] is the signal intensity I that is expected to be measured at the target mass number. ｍｅａｓ It is calculated as the total intensity of the spectral interference compared to (M).

[0049] According to the present invention, all mass numbers for which signal strengths have been calculated can be evaluated based on the interference level. Figure 9 shows an example of the relationship between the interference level and reliability, with the interference level divided into five levels.

[0050] 6 to 9 show the interference levels thus obtained along with an image of the periodic table, and further display the predicted results for the individual elements Cr, Ti, and S. Thus, according to the present invention, the reliability of the measurement for each element whose mass number has been determined can be understood at a glance, and detailed evaluation results for each element can also be understood. The evaluation results for each element can be displayed by selecting the corresponding element on the image of the periodic table with a pointer or by selecting it on a touch panel.

[0051] Figure 6 shows the reliability predictions for all elements expected to be measured in seawater applications, displayed on the periodic table in dark gray (no problem: see Cr, Mn, Fe, etc.) or diagonal lines (warning level: see Ni, Cu, Zn, etc.). This example clearly shows the degree of interference that may be present in each isotope of each element. It also displays the interference level for each isotope of Cr and information on interfering ions for the selected isotope.

[0052] Figure 7 shows predictions for drinking water applications using dark gray and hatched cells on the periodic table, similar to Figure 6. For titanium, mass numbers 47 m / z and 49 m / z are predicted, showing no overlapping interference at 47 m / z, but a large overlapping sulfur-related interference at 49 m / z. Figure 8 also shows prediction results for drinking water applications, showing a heat map with five gray levels on the periodic table, indicating that high concentrations of sulfur are predicted. Industrial Applicability

[0053] The interference prediction method and apparatus provided by the present invention can be widely used in the field of mass spectrometry, including the selection of useful mass spectrometry methods.

[0054] 100 Inductively coupled plasma mass spectrometer 110 Sample collection section 120 Sample introduction section 130 Inductively coupled plasma ion source 140 Interface 150 Ion lens 160 Collision / reaction cell 170 Mass filter 180 Detector

Claims

1. A method for predicting spectral interferences in mass analysis methods used in an inductively coupled plasma mass spectrometer, comprising: selecting a mass analysis method and an associated response factor from a database storing a plurality of mass analysis methods, each of which specifies the mass analysis conditions, and a response factor indicating the correlation between elements and their signal intensities for each mass analysis method; selecting an application from an application library that collects applications specifying the type and amount of elements; estimating the signal intensities indicating each element and the signal intensities indicating interference components for each element, as specified in the selected application; and displaying the predicted spectral interferences for each element.

2. The method of claim 1, wherein the mass analysis conditions include at least one of plasma conditions, cell conditions, and sample introduction conditions.

3. The method of claim 2, wherein the plasma conditions include radio frequency power conditions, sampling depth, injector gas flow rate, injector gas species, and / or wet / dry conditions.

4. The method of claim 2, wherein the cell conditions include the presence or absence of a cell gas, the type of cell gas, and / or an interference reduction mechanism.

5. The method of claim 1, wherein the response factor is corrected according to the instrument configuration of the inductively coupled plasma mass spectrometer.

6. The method of claim 1, wherein the application library includes a plurality of applications with different matrix elements.

7. The method of claim 6, wherein the plurality of applications includes a drinking water application, a seawater application, and a sediment / soil extract application.

8. The method of claim 1, wherein the predicted spectral interference is an indication of interference levels indicated by the signal intensity representing each element versus the signal intensity representing the interfering component for each element.

9. The method of claim 8, wherein the display of the interference level includes a percentage display, a star rating display, and / or a heat map.

10. The method of claim 1, wherein the display of predicted spectral interferences is displayed along with an image of the periodic table.

11. The method of claim 1, wherein the signal intensity indicating the interfering component is estimated based on previously obtained interfering ion information regarding the mass number and production rate of compound ions and multiply charged ions produced during ionization of each element.

12. The method of claim 11, wherein the interfering ion information is obtained for each of the plasma conditions and measurement conditions used in the collision / reaction cell.

13. A computer program for predicting spectral interferences in mass analysis methods used in an inductively coupled plasma mass spectrometer, the computer program causing a computer to execute the following steps: selecting a mass analysis method and an associated response factor from a database storing multiple mass analysis methods, each specifying mass analysis conditions, and response factors indicating the correlation between elements and their signal intensities for each mass analysis method; selecting an application from an application library containing applications specifying the type and content of elements; estimating the signal intensities indicating each element specified in the selected application and the signal intensities indicating interference components for each element; and displaying the predicted spectral interferences for each element.

14. The computer program of claim 13, wherein the estimation step estimates the signal intensity indicating the interference component based on a table storing previously obtained information on interference ions related to the mass numbers and production rates of compound ions and multiply charged ions produced during the ionization of each element.

15. The computer program of claim 13, further comprising the step of correcting the response factor according to the configuration of the inductively coupled plasma mass spectrometer.

16. An apparatus for predicting spectral interferences in mass analysis methods used in an inductively coupled plasma mass spectrometer, comprising: a database storing a plurality of mass analysis methods, each of which defines mass analysis conditions, and a response factor indicating the correlation between elements and their signal intensities for each mass analysis method; an application library collecting applications that define the type and amount of elements; a processor capable of selecting a mass analysis method and an associated response factor from the database, selecting an application from the application library, and estimating the signal intensities indicating each element and the signal intensities indicating interference components for each element, as defined in the selected application; and a display that displays the predicted spectral interferences for each element.

17. The apparatus according to claim 16, further comprising a table storing previously obtained information on interference ions relating to the mass numbers and production rates of compound ions and multiply charged ions produced during ionization of each element.

18. The apparatus of claim 16, wherein the processor is capable of performing processing to correct the response factor depending on the configuration of the inductively coupled plasma mass spectrometer.

19. The apparatus of claim 16 operatively connected to an inductively coupled plasma mass spectrometry apparatus.

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