CN-122029423-A - Method for determining arsenic content

Abstract

A technique for quantifying As with high sensitivity in a subject sample in which Pb may coexist is provided. A method for determining the arsenic content in a subject sample in which lead may coexist is provided, which determines the arsenic content using the K alpha line intensity of arsenic in the spectrum of the subject sample measured according to an energy-dispersive fluorescent X-ray analysis method, a first standard curve for arsenic, and a first correction coefficient for correcting the overlapping of arsenic and lead. In this method, the first standard curve and the first correction coefficient are obtained using a plurality of standard samples including a first standard sample containing no arsenic.

Inventors

• NAKAO TAKAMI

Assignees

• 株式会社岛津制作所

Dates

Publication Date

20260512

Application Date

20240828

Priority Date

20231030

Claims (6)

1. 1. A method for determining the arsenic content in a subject sample in which lead may coexist, the method determining the arsenic content using the K alpha line intensity of arsenic in the spectrum of the subject sample measured by energy-dispersive fluorescent X-ray analysis, a first standard curve for arsenic, and a first correction coefficient for correcting the overlapping of arsenic and lead, The first standard curve and the first correction coefficient are obtained using a plurality of standard samples including a first standard sample containing no arsenic.
2. 2. The method of claim 1, wherein the plurality of standard samples further comprises one or more standard samples comprising arsenic and lead.
3. 3. The method of claim 1, wherein the plurality of standard samples further comprises two or more standard samples containing arsenic and lead in the same ratio.
4. 4. The method of claim 1, wherein the plurality of standard samples further comprises one or more standard samples that contain neither arsenic nor lead.
5. 5. The method of claim 1, wherein the lead content in the subject sample is further utilized in the determination of the arsenic content.
6. 6. The method of claim 5, further comprising determining a lead content in the subject sample using the L alpha line intensity of lead in the spectrum, a second standard curve for lead, and a second correction factor for correcting lead to arsenic overlap.

Description

Method for determining arsenic content Technical Field The present disclosure relates to a method of determining arsenic content, and more particularly, to a method of determining arsenic content in a subject sample in which lead may coexist. Background In the analysis by the energy-dispersive fluorescent X-ray analysis method, it has been conventionally known that the kα -ray characteristic X-ray peak energy of arsenic (As) has a value close to the lα -ray characteristic X-ray peak energy of lead (Pb). Therefore, in the fluorescent X-ray spectrum, there is a problem that one peak interferes with the other peak in the quantification of As or Pb because the kα -line peak of As overlaps with the lα -line peak of Pb. Regarding the quantification of Pb in a sample in which As and Pb coexist, japanese patent application laid-open No. 2007-003331 (patent document 1) discloses a technique for quantifying Pb by using the lβ line intensity of Pb in the case where a kβ line peak of As is detected in the spectrum of the sample. Prior art literature Patent literature Patent document 1 Japanese patent laid-open No. 2007-003331 Disclosure of Invention Technical problem to be solved by the invention In recent years, in pharmaceutical analysis or food analysis by energy-dispersive fluorescent X-ray analysis, it has been particularly desired to be able to quantify As with high sensitivity. In the sample in which As is mixed with Pb, as described above, the K.alpha.line peak of As overlaps with the L.alpha.line peak of Pb. Therefore, it is also considered to use the kβ line peak of As in the quantification of As. However, the peak intensity of the kβ line of As is about 1/5 of the peak intensity of the kα line of As, and quantification with high sensitivity cannot be expected. In addition, the peak of the kβ line of As overlaps with the peak of the lα line of Hg. Therefore, in the case where the sample contains Hg, it is difficult to quantify As even with the peak intensity of the kβ line. The present disclosure has been made in view of the above circumstances, and an object thereof is to provide a technique for quantifying As with high sensitivity in a target sample in which Pb may coexist. Solution to the above technical problems A method according to one aspect of the present disclosure is a method of determining an arsenic content rate in a subject sample in which lead may coexist, the method determining the arsenic content rate using a ka line intensity of arsenic in a spectrum of the subject sample measured according to an energy-dispersive fluorescent X-ray analysis method, a first standard curve for arsenic, and a first correction coefficient for correcting overlapping of arsenic and lead, wherein the first standard curve and the first correction coefficient are obtained using a plurality of standard samples including the first standard sample containing no arsenic. Effects of the invention According to one aspect of the present disclosure, there is provided a technique for quantifying As with high sensitivity in a subject sample in which Pb may coexist. Drawings FIG. 1 is a diagram showing an example of a standard curve of As prepared using 6 standard samples in which Pb and As are co-stored. FIG. 2 shows a spectrum measured by an energy dispersive fluorescent X-ray analysis method of a sample. Fig. 3 is a diagram showing an example of a standard curve defined by the term "bj·ij+cj" in the formula (1) prepared from a plurality of standard samples in which Pb and As coexist. Fig. 4 schematically shows the overall configuration of an analysis system including an energy-dispersive fluorescent X-ray analysis device. Fig. 5 is a diagram showing a hardware configuration of the information processing apparatus 20. Fig. 6 is a diagram showing an example of a screen displayed when creating an correction formula. Fig. 7 is a diagram showing another example of a screen displayed when creating an correction formula. Fig. 8 is a diagram showing an example of a screen displaying the created correction expression. Fig. 9 is a flowchart of the processing performed by the information processing device 20 to quantify the As concentration in an unknown sample. Detailed Description Embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. In the drawings, the same or corresponding portions are denoted by the same reference numerals, and the description thereof will not be repeated. [ Disclosure summary ] The present disclosure generally describes a method of determining the content of As in a subject sample in which Pb and As may coexist. FIG. 1 is a diagram showing an example of an As standard curve prepared using 6 standard samples in which Pb and As coexist. In fig. 1, the horizontal axis represents the standard value (As concentration in the standard sample). In fig. 1, the vertical axis represents the measured intensity ratio with respect to As. The measured intensity rati