Plasma-based elemental analysis device

Abstract

To provide an element analyzing device using plasma capable of shortening a time from device activation to analysis start.SOLUTION: An element analyzing device (ICP-MS 10) comprises: a plasma generation unit (plasma torch 113); a specimen / rinse liquid introduction unit (auto-sampler 12) for selectively introducing any one of a specimen and a rinse liquid to plasma generated by the plasma generation unit; an element analysis unit (mass spectrometer 15) for executing element analysis by detecting ion or light generated by ionizing or atomizing elements contained in the specimen or the rinse liquid by the plasma; an analysis execution control unit 17 for controlling the specimen / rinse liquid introduction unit and the element analysis unit so as to execute element analysis of the rinse liquid by the element analysis unit after introducing the rinse liquid to the plasma before an operation for lighting out the plasma after element analysis of the specimen is executed by the element analysis unit; and an element analysis result display unit 19 for displaying the result of the element analysis executed to the rinse liquid.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an elemental analyzer using a plasma, such as an inductively coupled plasma-mass spectrometer (ICP-MS) or an inductively coupled plasma-atomic emission spectrometer (ICP-AES).

Background Art

[0002] In ICP-MS, ions generated by introducing a sample from a sample introduction system into an argon plasma generated in a plasma torch having an induction coil through which a high-frequency current flows are converged by an ion converging section such as an ion lens, and then mass-separated by a mass separator such as a quadrupole mass filter and detected by a detector, thereby performing qualitative and quantitative analysis of each element contained in the sample.

[0003] In order to perform accurate analysis in ICP-MS, it is necessary that the inside of the apparatus is not contaminated by the sample introduced in the previous analysis. In order to perform analysis on a sample in such a non-contaminated state, in the ICP-MS described in Patent Document 1, after the apparatus is started and before analyzing the sample, analysis using pure water is performed. As a result of the analysis with pure water, if no element exceeding a predetermined value is detected in any of the preset elements to be analyzed, the analysis of the sample is executed. On the other hand, if an element exceeding a predetermined value is detected in one or more of the elements to be analyzed as a result of the analysis with pure water, the analyst is notified that contamination has occurred by means of character display, lamp lighting, etc. The analyst who receives this notification stops the apparatus and performs maintenance such as cleaning the apparatus and replacing parts.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

[0005] In the ICP-MS described in Patent Document 1, analysis of pure water is performed before the analysis of the sample begins, which requires time before the analysis of the sample can start. Furthermore, if contamination is detected as a result of the analysis of the pure water, the device must be stopped and maintenance performed, and only after restarting the device can the analysis of the sample to be measured begin, thus further increasing the time required before the analysis of the sample can begin.

[0006] Up to this point, we have explained using ICP-MS with inductively coupled plasma as the ion source as an example, but similar problems arise in ICP-AES with inductively coupled plasma as the light source, and even in elemental analyzers that perform elemental analysis of liquid or powder samples using plasmas other than inductively coupled plasma as the ion source or light source.

[0007] The problem that this invention aims to solve is to provide an elemental analysis apparatus using plasma that can shorten the time from the startup of the apparatus to the start of analysis. [Means for solving the problem]

[0008] To solve the above problems, the plasma-based elemental analysis apparatus according to the present invention was developed. A plasma generation unit that generates plasma, A sample / rinse liquid introduction unit selectively introduces either a sample or a rinse liquid into the plasma generated by the plasma generation unit, An elemental analysis unit that performs elemental analysis by detecting ions or light generated when elements contained in the sample or rinse solution are ionized or atomized by the plasma, An analysis execution control unit controls the sample / rinse liquid introduction unit and the elemental analysis unit, such that after performing elemental analysis of the sample by the elemental analysis unit, before turning off the plasma, the rinse liquid is introduced into the plasma and then the elemental analysis of the rinse liquid is performed by the elemental analysis unit. The aforementioned After elemental analysis of the rinse solution has been performed and before the plasma is lit for the elemental analysis of the next sample, An elemental analysis result display unit that displays the results of elemental analysis performed on the rinse solution. It is equipped with. [Effects of the Invention]

[0009] In the elemental analyzer according to the present invention, after the analysis of the sample is completed, the analysis execution control unit, before turning off the plasma (without stopping the plasma), introduces a rinse solution (e.g., pure water) into the plasma from the sample / rinse solution introduction unit, and then executes control to perform elemental analysis of the rinse solution in the elemental analysis unit. After the elemental analysis of the rinse solution is performed, the plasma is turned off (stopped). If an amount of element exceeding a predetermined value is detected by the elemental analysis of the rinse solution, the result is displayed on the elemental analysis result display unit, and the analyst then performs maintenance such as cleaning the device or replacing parts. On the other hand, if an amount of element exceeding a predetermined value is not detected by the elemental analysis of the rinse solution, the operation can be terminated as is. In either case (by performing maintenance before the next device startup in the former case), it is not necessary to perform analysis of the rinse solution (pure water) when the device is started up again, and the analysis of the sample can be performed immediately, thus shortening the time until the start of sample analysis. [Brief explanation of the drawing]

[0010] [Figure 1] A schematic diagram showing an ICP-MS, which is a first embodiment of the elemental analyzer according to the present invention. [Figure 2] A flowchart illustrating the operation of the ICP-MS in the first embodiment. [Figure 3A] A diagram showing an example of an image displayed on a display in the ICP-MS of the first embodiment, where the detection intensity of ions in the sample is below the threshold. [Figure 3B] A figure showing another example of an image displayed on the display in the ICP-MS of the first embodiment, in which the detection intensity of ions in the sample is above a threshold. [Figure 4] A schematic diagram showing an ICP-AES, which is a second embodiment of the elemental analyzer according to the present invention. [Modes for carrying out the invention]

[0011] An embodiment of the elemental analysis apparatus using plasma according to the present invention will be explained with reference to Figures 1 to 4.

[0012] (1) Configuration of ICP-MS, an elemental analyzer using plasma according to the first embodiment Figure 1 shows the configuration of an ICP-MS10, an elemental analyzer using plasma according to the first embodiment. This ICP-MS10 comprises an ICP ion source 11, an autosampler 12, and a mass spectrometer (corresponding to the elemental analysis unit described above) 15. The ICP ion source 11 is housed in an ionization chamber 100 at approximately atmospheric pressure, and the mass spectrometer 15 is housed in a vacuum chamber 103 that is evacuated by a rotary pump and a turbomolecular pump (these pumps are not shown). A first intermediate vacuum chamber 101 and a second intermediate vacuum chamber 102 are provided between the ionization chamber 100 and the vacuum chamber 103.

[0013] The ICP ion source 11 includes a nebulizer 111 that atomizes the liquid sample supplied from the autosampler 12 with a carrier gas 91, a spray chamber 112 that separates and passes smaller particles of the liquid sample mist generated by the nebulizer 111, and a plasma torch (plasma generation unit) 113. The plasma torch 113 includes a sample tube through which the liquid sample mist and carrier gas that have passed through the spray chamber 112 flow, an auxiliary gas tube formed on the outer circumference of the sample tube through which an auxiliary gas passes, and a plasma tube formed on the outer circumference of the auxiliary gas tube through which plasma gas passes (these tubes are not shown). A coil 1131 is wound around the outside of the plasma tube.

[0014] The autosampler 12 has a liquid sample storage section 121 for storing a liquid sample to be analyzed and a rinse liquid storage section 122 for storing pure water as a rinse liquid, and corresponds to the sample / rinse liquid introduction section. In FIG. 1, only one liquid sample storage section 121 is shown, but a plurality of liquid sample storage sections 121 may be provided so that a plurality of types of samples can be sequentially analyzed. These liquid sample storage section 121 and rinse liquid storage section 122 are connected to the nebulizer 111 by a liquid introduction pipe 123. An arm 124 movable between the liquid sample storage section 121 and the rinse liquid storage section 122 is provided on the liquid introduction pipe 123. By moving this arm 124, only one of the liquid sample storage section 121 and the rinse liquid storage section 122 is selectively communicated with the nebulizer 111. Instead of using the arm 124, the liquid introduction pipe 123 may be branched and connected to the liquid sample storage section 121 and the rinse liquid storage section 122 respectively, and a switching valve for switching the flow path may be provided so that only one of the liquid sample storage section 121 and the rinse liquid storage section 122 is selectively communicated with the nebulizer 111.

[0015] The mass spectrometer 15 includes a quadrupole mass filter 151 including a pre-rod electrode and a main rod electrode, and an ion detector 152.

[0016] An ion lens 14 for converging ions is disposed in the second intermediate chamber 102.

[0017] The ICP-MS 10 further includes an analysis execution control section 17, a data analysis section 18, a data storage section 181, and an elemental analysis result display section 19.

[0018] The analysis execution control unit 17 controls the operations of the ICP ion source 11, the autosampler 12, the ion lens 14, and the mass spectrometer 15. Here, for the autosampler 12, the analysis execution control unit 17 moves the arm 124 to communicate the liquid sample storage unit 121 with the nebulizer 111 to perform the analysis of the liquid sample. After that, without stopping the plasma torch 113, the control is performed so that the arm 124 is moved to communicate the rinse liquid storage unit 122 with the nebulizer 111 to perform the analysis of the rinse liquid.

[0019] For the mass spectrometer 15, control is performed to execute qualitative analysis or quantitative analysis according to the purpose of the analysis. When the purpose is to identify the types of elements contained in the sample, the quadrupole mass filter 151 is controlled to switch the m / z of the ions reaching the ion detector 152 within a predetermined range (qualitative analysis). On the other hand, when precisely determining the content of a specific element, the quadrupole mass filter 151 is controlled to fix the m / z to the value of the element, and detection is performed by the ion detector 152 over a longer time than in qualitative analysis, and quantification is performed by applying the detection result to a calibration curve created in advance (quantitative analysis). Also, it is possible to first identify the types of elements contained in the sample by qualitative analysis and then perform quantitative analysis on the identified elements. Alternatively, when it is only necessary to roughly determine the content of the element, quantification may be performed based on the detection intensity for each m / z obtained during qualitative analysis (semi - quantitative analysis).

[0020] The data analysis unit 18 receives a detection signal from the ion detector 152 and determines the detection intensity for each m / z based on the detection signal. In the case of qualitative analysis, the elements contained in the sample are identified based on the data of the detection intensity. The obtained data of the detection intensity and the result of element identification are stored in the data storage unit 181. In the elemental analysis of the rinse liquid described later, after performing qualitative analysis, the detection intensity for each m / z obtained during the qualitative analysis is stored in the data storage unit 181.

[0021] The elemental analysis result display unit 19 comprises an elemental analysis result display control unit 191 and a display 192. Based on the data obtained by the data analysis unit 18, the elemental analysis result display control unit 191 controls the display 192 to display the quantitative results of the elements contained in the sample being analyzed obtained by quantitative analysis, and also controls the display to highlight the element name and its quantitative value for elements whose detection intensity exceeds a predetermined value. Furthermore, the elemental analysis result display unit 19 controls the display to highlight the element name and its semi-quantitative value for elements whose detection intensity obtained by semi-quantitative analysis of the rinse solution (pure water) sample exceeds a predetermined value.

[0022] The analysis execution control unit 17, the data analysis unit 18, and the elemental analysis result display control unit 191 are implemented by hardware such as a CPU and software.

[0023] In addition, the ICP-MS10 has input devices such as a keyboard, mouse, and touch panel for the analyst to input instructions for starting and ending the analysis (not shown in the diagram).

[0024] (2) Operation of the ICP-MS in the first embodiment The operation of the ICP-MS10 in the first embodiment will be explained using the flowchart in Figure 2.

[0025] First, the analyst opens the method file containing the measurement conditions by performing a predetermined operation (Step 1). However, at this point, only the hardware and software constituting the analysis execution control unit 17, the data analysis unit 18, and the elemental analysis result display unit 19 are started, and the plasma torch 113, etc., are not started.

[0026] The elemental analysis result display control unit 191 displays the results of the elemental analysis of the rinse solution (pure water) performed at the end of the previous analysis, which are stored in the data storage unit 181 along with the method file, on the display 192 (Step 2. For details regarding the elemental analysis of the rinse solution and its display, see Steps 7-9 below). The analyst confirms the analysis results of the rinse solution displayed on the display 192.

[0027] As a result, if the elemental name or semi-quantitative value (or detection intensity) indicating contamination of the device is not highlighted (details below), or if they are displayed but maintenance such as cleaning the device or replacing parts has been performed since the last analysis, then it is acceptable to proceed with the sample analysis. In these cases, the analyst will perform the prescribed operation to start the sample analysis, thereby igniting the plasma (YES in Step 3 → Step 5). On the other hand, if the above display is shown and maintenance has not been performed since the last analysis, the analyst will perform the maintenance without igniting the plasma (NO in Step 3 → Step 4). After the maintenance is completed, the analyst will perform the prescribed operation, proceeding to Step 5, and the plasma will be ignited.

[0028] After the plasma is lit, the analysis execution control unit 17 moves the arm 124 of the autosampler 12 so that the liquid sample storage unit 121 and the nebulizer 111 are in communication. As a result, the analysis of the sample contained in the liquid stored in the liquid sample storage unit 121 is performed as follows (step 6).

[0029] The liquid containing the sample in the liquid sample storage unit 121 is atomized through the nebulizer 111 and spray chamber 112 and introduced into the plasma torch 113, where the sample is ionized by the plasma generated in the plasma torch 113. The ionized sample passes through the first intermediate vacuum chamber 101 and the second intermediate vacuum chamber 102 and is introduced into the mass spectrometer 15 in the vacuum chamber 103. In the mass spectrometer 15, by changing the voltage applied to the quadrupole mass filter 151 over time, ions with different m / z values ​​at each time are detected by the ion detector 152. The data analysis unit 18 identifies the elements contained in the sample based on the timing (m / z) and detection intensity of these ions. The detection intensity for each m / z and the identified elements are stored in the data storage unit 181. In this step, further (or instead of the above operation), quantitative analysis is performed on the sample to be analyzed by fixing the m / z to a specific value and detecting ions.

[0030] After performing the analysis of one sample in this manner, if there are other samples to be analyzed (No in step 7), the system returns to step 6 to perform the analysis of the other samples. On the other hand, if there are no other samples to be analyzed (Yes in step 7), the system performs the analysis of the rinse solution while the plasma remains lit (step 8). For the analysis of the rinse solution, the analysis execution control unit 17 first moves the arm 124 of the autosampler 12 so that the rinse solution reservoir 122 and the nebulizer 111 are in communication. This introduces a mist of rinse solution (pure water) stored in the rinse solution reservoir 122 into the plasma torch 113. The rinse solution serves to clean the inside of the plasma torch 113 and the flow path leading to it, as well as to detect whether or not there is contamination by the sample. That is, if the inside of the plasma torch 113 and the flow path leading to it are not contaminated with the sample, the ion detector 152 will not detect ions originating from the sample, whereas if contamination occurs, ions originating from the sample will be detected by the ion detector 152 through the same process as when analyzing the sample.

[0031] The data analysis unit 18 identifies the detected elements and their semi-quantitative values ​​based on the detection intensity for each m / z obtained from the analysis of the rinse solution, and analyzes whether the semi-quantitative value (or detection intensity) for each identified element exceeds a predetermined threshold. The elements to be detected here may be limited to elements that can be contained in the sample being measured, or other elements may be included. If the elements to be detected are limited to elements that can be contained in the sample being measured, the elements to be limited and the thresholds corresponding to those elements may be stored in a method file in advance, and the data analysis unit 18 may refer to them. Alternatively, the software may determine the threshold corresponding to the element based on the concentration range set in the calibration curve used for the quantification of the elements to be detected, which is registered in the method file. The elemental analysis result display control unit 191 acquires the analysis result data from the data analysis unit 18, displays the identified elements and their semi-quantitative values ​​(same as above), and further controls the display 192 to highlight the elements whose semi-quantitative values ​​(same as above) exceed the threshold and the semi-quantitative values ​​(same as above) (step 9). The analyst checks the analysis results of the rinse solution displayed on display 192, and if there is a highlight indicating that the device is contaminated, they perform maintenance on the device immediately or before starting the next analysis.

[0032] After confirming the display on display 192, the analyst performs a predetermined operation to turn off the plasma (step 10), thereby completing the series of operations.

[0033] Figures 3A and 3B show examples of elemental analysis results for the rinse solution displayed on the display 192 in steps 2 and 9. Both Figures 3A and 3B display on the display 192 a table of semi-quantitative values ​​obtained based on the identified elements and their detection intensities. In the example in Figure 3A, none of the multiple elements to be analyzed were detected, so they are not highlighted. On the other hand, in the example in Figure 3B, two of the multiple elements to be analyzed (Fe and Ni) have semi-quantitative values ​​above the threshold, which are thought to be due to contamination by the sample. Therefore, these two elements are highlighted by displaying their element names and semi-quantitative values ​​in bolder letters than the other elements, and by displaying them with a different background color, so that the analyst can notice the presence of contamination. Note that the method of highlighting is not limited to this example; for example, the element names and semi-quantitative values ​​may be displayed in a different color than other elements, or symbols such as arrows or warning text may be displayed. Alternatively, the detection intensity may be displayed instead of the semi-quantitative value.

[0034] In conventional ICP-MS systems, when the instrument is started, the plasma is lit and pure water is analyzed. If elements indicating instrument contamination are detected, the plasma torch is turned off for instrument maintenance, and then the plasma is turned on again before starting the sample analysis. Thus, analysis of pure water is required before starting the sample analysis, and if the instrument is contaminated, the plasma torch has to be turned on and off repeatedly, which results in a long waiting period before the sample analysis can begin. In contrast, with the ICP-MS10 of this embodiment, it is not necessary to analyze the rinse solution (pure water) when the instrument is started, and once the plasma is lit, the sample can be analyzed without turning it off, thus shortening the time from instrument startup to the start of analysis.

[0035] (3) Configuration of the ICP-AES, an elemental analyzer using plasma according to the second embodiment. Figure 4 shows the configuration of the ICP-AES20, an elemental analyzer using plasma according to the second embodiment. The ICP-AES20 includes an ICP ion source 21, an autosampler 22, a focusing lens 23, a slit 24, a diffraction grating 25, and a multi-channel detector 26.

[0036] The ICP ion source 21 has the same configuration as the ICP ion source 11 in the ICP-MS10 of the first embodiment. The autosampler 22 has the same configuration as the autosampler 12 in the ICP-MS10 of the first embodiment, and includes a liquid sample reservoir 221, a rinse liquid reservoir 222, a liquid introduction tube 223, and an arm 224. By moving the arm 224, either the liquid sample or the rinse liquid is introduced into the nebulizer 211 of the ICP ion source 21. In the ICP ion source 21, the introduced liquid sample or rinse liquid is atomized in the nebulizer 211, introduced into the plasma torch 213 via the spray chamber 212, and then excited by the plasma flame. As a result, light having a specific wavelength corresponding to the elements contained in the liquid sample or rinse liquid is emitted.

[0037] The focusing lens 23 is a lens that focuses the light emitted by the plasma torch 213. The slit 24 allows a portion of the light focused by the focusing lens 23 to pass through. The diffraction grating 25 disperses the light that has passed through the slit 24 by wavelength. The multi-channel detector 26 detects the intensity of the light dispersed by the diffraction grating 25 at each wavelength. The intensity of the light at each wavelength detected here corresponds to the amount of elements corresponding to each wavelength contained in the liquid sample or rinsing solution. The diffraction grating 25 and the multi-channel detector 26 having the above functions correspond to the elemental analysis unit in the present invention.

[0038] The ICP-AES20 further comprises an analysis execution control unit 27, a data analysis unit 28, a data storage unit 281, and an elemental analysis result display unit 29. The elemental analysis result display unit 29 includes an elemental analysis result display control unit 291 and a display 292.

[0039] The analysis execution control unit 27 controls the plasma torch 213 and the autosampler 22. Here, with respect to the autosampler 22, the analysis execution control unit 27 controls it to move the arm 224 so that it connects the liquid sample storage unit 221 and the nebulizer 211 to perform analysis of the liquid sample, and then, without stopping the plasma torch 213, move the arm 224 so that it connects the rinse solution storage unit 222 and the nebulizer 211 to perform analysis of the rinse solution.

[0040] The data analysis unit 28 receives detection signals from the multi-channel detector 26 that correspond to the intensity of light at each wavelength detected by the multi-channel detector 26, and identifies and quantifies the elements contained in the sample based on these detection signals. The results of element identification and quantification are stored in the data storage unit 281.

[0041] The elemental analysis result display control unit 291 controls the display 292 to display the results of identifying and quantifying the elements contained in the sample, which were obtained by the data analysis unit 28. The display 192 displays the results based on the control of the elemental analysis result display control unit 291.

[0042] In addition, the ICP-AES20 has input devices such as a keyboard, mouse, and touch panel for the analyst to input instructions to start and end the analysis (not shown in the diagram).

[0043] (4) Operation of ICP-AES in the second embodiment The operation flow for analysis using ICP-AES20 is basically the same as that for ICP-MS. Therefore, we will explain the operation while referring to Figure 2.

[0044] First, the analyst turns on the power to the ICP-AES20 by performing a predetermined operation. At this point, only the hardware and software constituting the analysis execution control unit 27, the data analysis unit 28, and the elemental analysis result display unit 29 are started, and the plasma torch 213, etc., are not started.

[0045] The elemental analysis result display control unit 291 displays the results of the elemental analysis of the rinse solution (pure water) performed at the end of the previous analysis, which are stored in the data storage unit 281, on the display 292 (Step 2). The analyst checks the analysis results of the rinse solution displayed on the display 292. If no indication that the device is contaminated is displayed, or if such indications are displayed but maintenance has been performed since the end of the previous analysis, the plasma is turned on by performing a predetermined operation to start the analysis of the sample (YES in Step 3 → Step 5). On the other hand, if the above indications are displayed but maintenance has not been performed since the end of the previous analysis, maintenance is performed without turning on the plasma, and the plasma is turned on after the maintenance is completed (Step 5).

[0046] After the plasma is lit, the analysis execution control unit 27 moves the arm 224 of the autosampler 22 so that the liquid sample storage unit 221 and the nebulizer 211 are in communication. This performs analysis on the liquid sample (step 6). Specifically, the liquid containing the sample in the liquid sample storage unit 221 is atomized by the nebulizer 211, introduced into the plasma torch 213 via the spray chamber 212, and then excited by the plasma flame, causing light with a specific wavelength corresponding to the elements contained in the liquid sample to be emitted. The emitted light passes through the focusing lens 23 and slit 24 and is wavelength-dispersed by the diffraction grating 25, and the intensity for each wavelength is detected by the multi-channel detector 26. The detection signal from the multi-channel detector 26 is transmitted to the data analysis unit 28, where the elements contained in the sample are identified and quantified.

[0047] After performing the analysis on the liquid samples described above for all liquid samples to be analyzed (YES in step 7), the analysis on the rinse solution is performed with the plasma torch 213 still lit (step 8). Specifically, the analysis execution control unit 27 moves the arm 224 of the autosampler 22 so that the rinse solution reservoir 222 and the nebulizer 211 are in communication, thereby introducing a mist of rinse solution (pure water) into the plasma torch 213. The light emitted by the plasma torch 211 is then wavelength-dispersed by the diffraction grating 25, and the intensity for each wavelength is detected by the multi-channel detector 26.

[0048] The data analysis unit 28 performs element identification and quantification based on the detection signal from the multi-channel detector 26. If the plasma torch 213 and the flow path leading to it are not contaminated with the sample during liquid sample analysis, no ions originating from the sample will be detected during rinse solution analysis. However, if the above-mentioned area is contaminated with the sample during liquid sample analysis, light originating from the sample will be detected during rinse solution analysis. The elemental analysis result display control unit 291 acquires the analysis result data from the data analysis unit 28 and displays the analysis result on the display 292 (step 9). The analysis result data displayed here, as in the first embodiment, represents the identified elements and semi-quantitative values ​​(or detection intensity), and elements with semi-quantitative values ​​(or detection intensity) above a threshold can be highlighted.

[0049] The analyst checks the analysis results of the rinse solution displayed on display 292. If peaks in the spectrum indicating contamination of the device or characters indicating the presence of contamination are displayed, the analyst performs maintenance on the device immediately or before starting the next analysis. After checking the display on display 292, the analyst performs the prescribed operation to turn off the plasma (step 10), thereby completing the series of operations.

[0050] According to the ICP-AES20 of this embodiment, similar to the ICP-MS10, it is not necessary to analyze the rinse solution (pure water) when starting the device, and once the plasma torch is turned on, the sample can be analyzed without turning it off, thus shortening the time from device startup to the start of analysis. Furthermore, the analysis of the rinse solution (pure water) can be performed after the sample analysis without turning off the plasma torch, which also shortens the working time.

[0051] (5) Variations The present invention is not limited to the embodiments described above, and various modifications are possible.

[0052] In the above embodiment, pure water was used as the rinsing solution, but other rinsing solutions may be used. For example, a solvent used to dissolve solid samples when preparing liquid samples may be used as the rinsing solution.

[0053] The configurations of the ICP-MS and ICP-AES shown in the above embodiments are examples, and various configurations used in conventional ICP-MS and ICP-AES can be applied to the present invention. For example, in the ICP-MS, a collision cell / reaction cell may be provided in addition to the configuration of the above embodiments. In the ICP-AES, the optical system between the plasma torch 211 and the spectroscopic crystal 25 is not limited to that shown in the above embodiments, and various types can be used. Also, in the ICP-AES, instead of detecting light of different wavelengths with a multi-channel detector 26, a sequential configuration may be adopted in which the wavelength detected by the detector is changed by rotating the diffraction grating. The plasma generation unit is not limited to a plasma torch, and other means for generating plasma may be used.

[0054] [Aspect] It will be obvious to those skilled in the art that the exemplary embodiments described above are specific examples of the following embodiments.

[0055] (Section 1) The elemental analysis apparatus using plasma as described in paragraph 1 is A plasma generation unit that generates plasma, A sample / rinse liquid introduction unit selectively introduces either a sample or a rinse liquid into the plasma generated by the plasma generation unit, An elemental analysis unit that performs elemental analysis by detecting ions or light generated when elements contained in the sample or rinse solution are ionized or atomized by the plasma, An analysis execution control unit controls the sample / rinse liquid introduction unit and the elemental analysis unit, such that after performing elemental analysis of the sample by the elemental analysis unit, before turning off the plasma, the rinse liquid is introduced into the plasma and then the elemental analysis of the rinse liquid is performed by the elemental analysis unit. An elemental analysis result display unit that displays the results of elemental analysis performed on the rinse solution. It is equipped with.

[0056] In the elemental analyzer described in paragraph 1, after the analysis of the sample is completed, the analysis execution control unit, before turning off the lights (without stopping the plasma), introduces a rinse solution (e.g., pure water) into the plasma from the sample / rinse solution introduction unit, and then executes a control to perform elemental analysis of the rinse solution in the elemental analysis unit. After the elemental analysis of the rinse solution is performed, the plasma is turned off (stopped). If an amount of element exceeding a predetermined value is detected by the elemental analysis of the rinse solution, the result is displayed on the elemental analysis result display unit, and the analyst then performs maintenance such as cleaning the device or replacing parts. On the other hand, if an amount of element exceeding a predetermined value is not detected by the elemental analysis of the rinse solution, the operation can be terminated as is. In either case (by performing maintenance before the next device startup in the former case), it is not necessary to perform analysis of the rinse solution (pure water) when the device is started up again, and the analysis of the sample can be performed immediately, thus shortening the time until the start of sample analysis.

[0057] The timing at which the elemental analysis result display unit displays the results of the elemental analysis of the rinse solution may be after the elemental analysis of the rinse solution has been performed but before a predetermined termination operation (e.g., turning off the plasma) has been performed, or it may be after the termination operation has been performed. Alternatively, the results of the elemental analysis of the rinse solution may be displayed after a predetermined start operation (e.g., opening the measurement method) has been performed for the analysis of the next sample.

[0058] (Section 2) The elemental analysis apparatus using plasma according to paragraph 2 is an elemental analysis apparatus using plasma according to paragraph 1, wherein the elemental analysis result display unit displays the elements identified as being contained in the rinse liquid as a result of elemental analysis performed on the rinse liquid, and the quantitative value (including the semi-quantitative value) or detection intensity of the elements, and displays elements whose quantitative value or detection intensity is above a predetermined threshold, distinguishing them from other elements.

[0059] According to the elemental analyzer described in paragraph 2, as a result of elemental analysis of the rinse solution, elements with a quantitative value or detection intensity above a predetermined threshold on the spectrum that are highly likely to originate from contamination of the instrument are displayed separately from other elements, allowing the analyst to easily recognize contamination of the instrument. Here, the quantitative value or detection intensity can be obtained by mass spectrometry if the elemental analyzer is ICP-MS, or by wavelength spectrometry if the elemental analyzer is ICP-AES.

[0060] As stipulated in Section 4 below, when the results of elemental analysis of the rinse solution are displayed twice, the possibility of the user overlooking an element can be further reduced by distinguishing it from other elements in both displays if the quantitative value or detection intensity is above a predetermined threshold.

[0061] (Section 3) In the plasma-based elemental analyzer described in paragraph 3, the threshold is set for an element selected based on the information of the element to be measured, which is set when a predetermined start operation is performed to initiate elemental analysis of the sample, as in the plasma-based elemental analyzer described in paragraph 2.

[0062] According to the elemental analyzer described in paragraph 3, the threshold is set for the element selected based on the information of the element to be measured (which may be contained in the sample) that is set when the start operation is performed (for example, registered in the method file). Therefore, it is possible to accurately detect whether the element to be measured is mixed in the rinse solution, that is, whether the device is contaminated by the sample to be measured.

[0063] (Section 4) The elemental analyzer using plasma described in paragraph 4 is an elemental analyzer using plasma described in any one of paragraphs 1 to 3, The elemental analysis result display unit is, After elemental analysis of the rinse solution has been performed and before the predetermined start operation for starting the elemental analysis of the next sample is carried out, the results of the elemental analysis of the rinse solution are displayed. From the time the start operation for the elemental analysis of the next sample is performed until the elemental analysis of the next sample begins, the results of the elemental analysis of the rinse solution performed after the completion of the elemental analysis of the previous sample will be displayed.

[0064] According to the elemental analyzer described in paragraph 4, the results of the elemental analysis of the rinse solution are displayed twice: once after performing the elemental analysis on the rinse solution and before starting the elemental analysis of the next sample, and again after starting the elemental analysis of the next sample. This reduces the possibility that the user may overlook the detection of an amount of element exceeding a predetermined value in the rinse solution. [Explanation of Symbols]

[0065] 10…ICP-MS 100... Ionization chamber 101...First intermediate vacuum chamber 102...Second Intermediate Vacuum Chamber 103...Vacuum chamber 11…ICP ion source 111, 211... Nebulizer 112, 212… spray chamber 113, 213... Plasma torch 12, 22... Autosampler 121, 221... Liquid sample storage section 122, 222... Rinse liquid storage section 123, 223...Liquid introduction pipe 124, 224...arm 14…Ion lens 151... Quadrupole Mass Filter 152... Ion detector 17, 27…Analysis Execution Control Unit 18, 28…Data Analysis Department 181, 281…Data storage unit 19, 29...Elemental analysis result display section 191, 291... Elemental Analysis Result Display Control Unit 192, 292… displays 20…ICP-AES 23… Focusing lens 24... Slit 25...Diffraction grating 26…Multi-channel detector

Claims

1. A plasma generation unit that generates plasma, A sample / rinse liquid introduction unit selectively introduces either a sample or a rinse liquid into the plasma generated by the plasma generation unit, An elemental analysis unit that performs elemental analysis by detecting ions or light generated when elements contained in the sample or rinse solution are ionized or atomized by the plasma, An analysis execution control unit controls the sample / rinse liquid introduction unit and the elemental analysis unit, such that after performing elemental analysis of the sample by the elemental analysis unit, before turning off the plasma, the rinse liquid is introduced into the plasma and then the elemental analysis of the rinse liquid is performed by the elemental analysis unit. An elemental analysis result display unit that displays the results of the elemental analysis performed on the rinse solution after the elemental analysis of the rinse solution has been performed and before the plasma is turned on for the elemental analysis of the next sample. A plasma-based elemental analyzer equipped with the necessary features.

2. The elemental analysis result display unit displays the elements identified as being contained in the rinse liquid as a result of elemental analysis performed on the rinse liquid, and the quantitative value or detection intensity of those elements, and displays elements whose quantitative value or detection intensity is above a predetermined threshold, distinguishing them from other elements, as described in claim 1.

3. The elemental analyzer using plasma according to claim 2, wherein the threshold is set for an element selected based on information of the element to be measured, which is set when a predetermined start operation is performed to start elemental analysis of the sample.

4. A plasma generation unit that generates plasma, A sample / rinse liquid introduction unit selectively introduces either a sample or a rinse liquid into the plasma generated by the plasma generation unit, An elemental analysis unit that performs elemental analysis by detecting ions or light generated when elements contained in the sample or rinse solution are ionized or atomized by the plasma, An analysis execution control unit controls the sample / rinse liquid introduction unit and the elemental analysis unit, such that after performing elemental analysis of the sample by the elemental analysis unit, before turning off the plasma, the rinse liquid is introduced into the plasma and then the elemental analysis of the rinse liquid is performed by the elemental analysis unit. An elemental analysis result display unit that displays the results of elemental analysis performed on the rinse solution. Equipped with, The elemental analysis result display unit, After elemental analysis of the rinse solution has been performed and before the predetermined start operation for starting the elemental analysis of the next sample is carried out, the results of the elemental analysis of the rinse solution are displayed. From the time the aforementioned start operation for the elemental analysis of the next sample is performed until the elemental analysis of the next sample begins, the results of the elemental analysis of the rinse solution performed after the completion of the elemental analysis of the previous sample are displayed. A plasma-based elemental analysis device.

Images