Conjoint analysis method for iron-55 and nickel-63 in urine sample

Abstract

The invention relates to a combined analysis method of iron-55 and nickel-63 in a urine sample, which comprises the following steps: adding concentrated hydrochloric acid, Fe < 3 + >, Ni < 2 + > and hydrogen peroxide into the urine sample for pretreatment, carrying out oxidation treatment on the urine sample by using hydrogen peroxide, carrying out coprecipitation by using sodium hydroxide, separating and purifying 55Fe and 63Ni in the sample by using a method of combining anion exchange resin with dimethylglyoxime precipitation, and measuring the purified 55Fe and 63Ni by using a liquid scintillation counter. According to the method, the radiochemical separation process of 55Fe and 63Ni in a group of eight urine samples only needs 5 hours, the method is a rapid and accurate combined measurement method, detection of two radioactive elements of 55Fe and 63Ni can be achieved at the same time, and the defects that in the prior art, a method for measuring 55Fe in a urine sample is long in time consumption, and 55Fe and 63Ni cannot be measured at the same time are overcome.

Description

Technical Field

[0001] The invention relates to the technical field of radioactive element detection and analysis, and in particular to a combined analysis method of iron-55 and nickel-63 in urine samples. Background Art

[0002] Radioactive iron-55( 55 Fe) and radioactive nickel-63( 63 Ni) is a common radioactive isotope in nuclear facilities, and its production process is mainly related to neutron activation. In nuclear facilities, structural materials (such as pipelines, pressure vessels, etc.) are usually made of alloys containing iron and nickel. When the reactor is running, the neutrons in the reactor interact with these structural materials. 55 Fe is produced by neutron irradiation of two stable isotopes of iron: 54 Fe(n,γ) 55 Fe and 56 Fe(n,2n) 55 Fe, 63 Ni is produced by neutron irradiation of nickel and copper: 62 Ni(n,γ) 63 Nihe 63 Cu(n,P) 63 You. 55 Fe and 63 Ni has a long half-life of 2.7 and 100.1 years respectively, which means they can persist in the environment for a long time.

[0003] During nuclear facility overhaul and decommissioning activities, activated metals are corroded into the coolant and may enter the human body through various pathways (e.g., inhalation, ingestion, or wounds). Once radioactive materials enter the body, they continue to release radiation, which may cause cell damage, increase the risk of cancer, and other health problems. Internal exposure is a special concern, especially for nuclear workers who are exposed to low levels of radioactive materials for a long time. 55 Fe and 63 Ni mainly emits β particles, and although their β radiation energy is relatively low, the long-term cumulative effect cannot be ignored.

[0004] In order to assess whether nuclear practitioners are 55 Fe and 63 To monitor the internal irradiation of Ni and estimate its effective dose, it is very important to measure biological samples. Commonly used biological monitoring methods include analyzing the radioactivity concentration in urine, feces or blood. Among them, urine is the most convenient sample type to collect.

[0005] The determination of radioactive iron-55 and nickel-63 in urine samples is a complex process. The main challenges are the low concentrations of these isotopes and the complexity of the urine matrix. Currently, only a few methods have been reported for the determination of radioactive iron-55 and nickel-63 in urine samples. 55 Fe, for urine 63 The measurement of Ni has rarely been reported. In order to pre-concentrate iron from the urine matrix, a large amount of sample needs to be evaporated to a near-dry state, and then the residue is ashed. Finally, multiple iron hydroxide precipitation, solvent extraction, and extraction chromatography are used to extract iron. Among them, the multiple iron hydroxide precipitation method utilizes the characteristic that iron ions form iron hydroxide precipitates under alkaline conditions. By adjusting the pH value of the solution, iron ions can be combined with hydroxide ions to form insoluble iron hydroxide precipitates, thereby separating iron from the complex urine matrix. The solvent extraction method is based on the complexation between iron ions and specific organic extractants, transferring iron from the aqueous phase to the organic phase to achieve separation. The extraction chromatography method uses the selective interaction between the functional groups on the stationary phase and the target element to achieve effective separation of the target element from other impurities.

[0006] Although the above methods can usually achieve a high iron recovery rate, the operation process of these methods is extremely time-consuming, and the radiochemical separation process usually takes more than two days. Therefore, there is an urgent need for a method that is easy to operate, takes less time, and can simultaneously separate, purify and accurately detect urine samples. 55 Fe and 63 Your method. Summary of the invention

[0007] The present invention discloses a combined analysis method of iron-55 and nickel-63 in urine samples, aiming to solve the problem of the existing technology in urine samples. 55 Fe and 63 The Ni detection method has the technical problems of complex operation and long detection time. 55 Fe and 63 The combined measurement method of Ni is that urine samples are oxidized with hydrogen peroxide and co-precipitated with sodium hydroxide, and then anion exchange resin and dimethylglyoxime precipitation are used to separate and purify the Ni in the sample. 55 Fe and 63 Ni, purified 55 Fe and 63 Ni was measured using a liquid scintillation counter (LSC).

[0008] The present invention adopts the following technical solutions:

[0009] The present invention provides a combined analysis method for iron-55 and nickel-63 in urine samples, comprising the following steps:

[0010] S1: Urine sample pretreatment

[0011] Add concentrated hydrochloric acid, Fe 3+ 、Ni 2+ and hydrogen peroxide, after heating, adjust the pH to alkaline with solid sodium hydroxide, stir, centrifuge the sample, discard the supernatant, wash the precipitate, and dissolve it with concentrated hydrochloric acid to obtain a sample solution;

[0012] S2: Radiochemical separation of samples

[0013] Fill the resin column with anion exchange resin, pre-treat it with hydrochloric acid, and set it aside;

[0014] The sample solution was passed through an anion exchange resin, and the effluent was collected and labeled as the Ni component;

[0015] The anion exchange resin was washed with 12 mol / L HCl and 6 mol / L HCl in sequence. After washing, the anion exchange resin was eluted with 0.1 mol / L HCl. The eluent was marked as 55 Fe test solution, measure the recovery rate of iron and 55 Fe activity;

[0016] S3: Separation and measurement of Ni components

[0017] Add citric acid and dimethylglyoxime ethanol solution to the effluent, adjust the pH to alkaline with ammonia water, generate a precipitate, centrifuge, discard the supernatant, wash the precipitate, dissolve it with concentrated hydrochloric acid, centrifuge, discard the trace insoluble matter, retain the supernatant and mark it as 63 Ni test solution, measure the nickel recovery and 63 Your activity.

[0018] Preferably, in step S1, 5‰ to 5% (v / v) 12 mol / L concentrated hydrochloric acid, 2 to 10 mg Fe 3+ , 2~5mg Ni 2+ and 1‰~1% (v / v) 30% hydrogen peroxide.

[0019] Preferably, in step S1, the heating temperature is 70-120° C. and the heating time is 8-12 min; the pH is adjusted to 8-10 with solid sodium hydroxide, and the mixture is stirred for 10-30 min before centrifugation.

[0020] Preferably, in step S1, after dissolving with 12 mol / L concentrated hydrochloric acid, high-purity water is used to adjust the system to 9 mol / L HCl.

[0021] More preferably, in step S1, the precipitate is washed with high-purity water.

[0022] In the detection process of two radioactive elements, radioactive iron-55 and radioactive nickel-63, urine, which is the most convenient to collect, is selected as a sample. However, urine contains water, electrolytes, organic acids and alkalis, proteins, sugars, amino acids and other substances, and the matrix components are complex. The complex matrix of urine may produce a matrix effect on the separation and measurement of radioactive isotopes, that is, other components in urine will affect the extraction efficiency, recovery rate and measurement accuracy of the target elements. This is also the difficulty of using urine as a sample for radioactive element detection. In view of the above problems, the present invention designs a specific urine sample pretreatment process, in which concentrated hydrochloric acid, Fe 2+ and HCl are added to the urine sample. 3+ 、Ni 2+ and hydrogen peroxide, and combined with the heating process, the extraction and separation efficiency of the target elements can be significantly improved. Concentrated hydrochloric acid (HCl) is a strong acid that can effectively destroy the complex matrix of urine samples, such as proteins, organic matter and other interfering substances. By lowering the pH value of the solution, concentrated hydrochloric acid can release metal ions from a bound state to a free state, making them easier to be captured by subsequent separation and enrichment processes. Hydrogen peroxide is a strong oxidant that can oxidize organic matter in urine samples, further destroy the complex organic matrix, and reduce the adsorption and encapsulation of metal ions by organic matter. In addition, hydrogen peroxide can also oxidize certain low-valent metal ions, making them easier to react with acids, thereby increasing the solubility of metal ions. During the heating process, the chemical reaction can be accelerated, and then the pH is adjusted to alkaline (pH 8-10) with solid sodium hydroxide to obtain iron hydroxide precipitate and nickel hydroxide precipitate, which promotes the precipitation of target metal ions. The present invention adds concentrated hydrochloric acid, Fe 3+ 、Ni 2+ and hydrogen peroxide, which can simultaneously achieve multiple functions such as matrix destruction, metal ion release, and precipitation formation, simplifying the pretreatment steps and reducing the operation time.

[0023] Preferably, in step S2, the anion exchange resin is loaded into a 2 mL resin column, pretreated with 9 mol / L HCl, and then set aside.

[0024] Preferably, in step S2, the sample solution passes through the anion exchange resin column at a flow rate of 0.5 to 3 mL / min.

[0025] Preferably, in step S2, the anion exchange resin column is eluted with 20 to 40 column volumes of 12 mol / L HCl at a flow rate of (0.5 to 3) mL / min and 3 to 5 column volumes of 6 mol / L HCl at a flow rate of (0.5 to 3) mL / min, respectively. After elution, Fe is eluted with 1 to 3 column volumes of 0.1 mol / L HCl at a flow rate of (0.5 to 3) mL / min.

[0026] Preferably, in step S2, the method for measuring the iron recovery rate is one of an inductively coupled plasma atomic emission spectrometer, an ultraviolet spectrophotometer or an X-ray fluorescence spectrometer; 55 The Fe activity was measured using a liquid scintillation counter.

[0027] More preferably, in step S2, the anion exchange resin is a strongly basic anion exchange resin, specifically AGMP-1 anion exchange resin.

[0028] After the urine sample is pre-treated, almost all the target metal ions to be detected are enriched to obtain a sample solution, which is convenient for subsequent separation. The present invention separates iron-55 and nickel-63 in the sample solution through anion exchange resin, thereby achieving effective separation of the two radioactive elements. Anion exchange resin has a high selectivity for metal ions and can effectively separate Fe 3+ and Ni 2+ Separate, especially for 55 Fe and 63 Ni, these two radioactive isotopes, anion exchange resin can achieve highly selective capture and elution, ensuring the effective separation of target elements and other impurities. 55 Fe remains in the anion exchange resin, 63 Ni exists in the effluent, achieving 55 Fe and 63 Effective separation of Ni. 55 Fe, the present invention gradually uses different concentrations of hydrochloric acid (12mol / L and 6mol / L) for elution, and uses 0.1mol / L hydrochloric acid for elution to obtain a high purity 55 The Fe test solution is used for subsequent testing to obtain more accurate results. The use of two different concentrations of hydrochloric acid for elution can be used to elute other interfering metal ions in stages, removing potential metal ions on the resin column that may affect 55 The multi-step elution strategy not only improves the separation efficiency but also ensures a high recovery rate. 55 Fe is resolved from the resin column and the eluted 55 Fe test solution can be used to measure the recovery rate of iron and radioactive elements 55 Activity of Fe.

[0029] Preferably, in step S3, 0.2 mL of 2% (w / v) citric acid and 2-5 mL of 1% (w / v) dimethylglyoxime ethanol solution are added to the effluent, and aqueous ammonia is added to adjust the pH to 8-10.

[0030] Preferably, in step S3, the method for measuring the nickel recovery rate is one of an inductively coupled plasma atomic emission spectrometer, an ultraviolet spectrophotometer or an X-ray fluorescence spectrometer. 63 The Ni activity was measured using a liquid scintillation counter.

[0031] At present, the existing technology for radioactive elements 63 There are few methods for detecting Ni. To address this problem, the present invention uses an anion exchange resin to obtain 55 The Fe test solution was prepared and the recovery rate and activity were tested. The effluent containing most of the nickel components was also post-treated. The present invention adds citric acid and dimethylglyoxime ethanol solution to the effluent to form a Ni precipitate, which is then acid-dissolved and centrifuged, and finally measured. 63 After adding citric acid and dimethylglyoxime ethanol solution, other interfering ions will combine with citrate to form a stable soluble complex, Ni 2+ It will quickly form an insoluble complex precipitate with diacetyl oxime. This process is very fast and can usually be completed within a few minutes. The present invention can greatly shorten the separation time while removing the potential interfering nuclides during measurement. Compared with traditional extraction, column separation, etc. 63 The purification method of Ni can achieve more efficient precipitation using diacetyl oxime, reducing the number of operation steps and time cost.

[0032] The technical solution adopted by the present invention can achieve the following beneficial effects:

[0033] (1) The present invention adds concentrated hydrochloric acid, Fe 3+ 、Ni 2+ The complex matrix of urine samples can be quickly destroyed by adding hydrogen peroxide and heating, making metal ions easier to extract. Then, solid sodium hydroxide is used to adjust the pH to alkaline to form a precipitate, which greatly simplifies the pre-treatment steps.

[0034] (2) The use of anion exchange resin columns in the present invention makes the separation of Fe and Ni more efficient, mainly because Fe 3+ It can form anion complex under high concentration hydrochloric acid conditions and be adsorbed by anion exchange resin, while Ni 2+ No anion complex will be formed and cannot be adsorbed by anion exchange resin. Therefore, the sample can be 55 Fe and 63 Specifically, the present invention uses two different concentrations of hydrochloric acid to first elute the anion exchange resin adsorbed with Fe components. This is mainly because when internal irradiation occurs in nuclear power plants, other radionuclides (such as 55 Homologous radionuclides of Fe60 Co. 137 Cs, etc.), in order to remove these effects 55 For the potential radionuclides measured by Fe liquid scintillation, the resin column needs to be eluted with hydrochloric acid of different concentrations to allow the interfering nuclides to dissociate into the eluent first, and then the Fe component in the anion exchange resin is eluted with low concentration of hydrochloric acid to ensure that the eluted Fe component has a high purity and improve the detection accuracy.

[0035] (3) In the separation process of the Ni component, the present invention adds citric acid and dimethylglyoxime ethanol solution, utilizes citric acid to form a stable soluble complex with other interfering elements, reduces the influence of interfering elements on the Ni component activity test, utilizes dimethylglyoxime to form a stable precipitated complex with Ni, and finally utilizes centrifugal operation to separate the soluble complex from the precipitated complex, thereby achieving the purification of Ni in the effluent and improving the selectivity and recovery rate of Ni.

[0036] (4) In the present invention, all steps from urine sample pretreatment to final radioactivity measurement are carefully designed, which reduces complex manual operations, reduces human errors, and ensures the reproducibility and reliability of the results.

[0037] (5) The present invention uses cross-validation through multiple means (such as inductively coupled plasma atomic emission spectrometer, ultraviolet spectrophotometer, X-ray fluorescence spectrometer, liquid scintillation counter, etc.) to ensure the reliability and accuracy of the data.

[0038] (6) The method of the present invention is used to detect the presence of 8 urine samples. 55 Fe, 63 The radiochemical separation process of Ni takes only 5 h, which is a fast and accurate combined measurement method. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments, which constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions explain the present invention and do not constitute improper limitations on the present invention. In the drawings:

[0040] Figure 1 is a process flow chart of the present invention;

[0041] Figure 2 for 55 LSC measurement spectrum of Fe;

[0042] Figure 3 for 63 LSC measurement spectrum of Ni. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. In the description of the present invention, it should be noted that the term "or" is usually used in the sense of including "and / or", unless the content clearly indicates otherwise. The described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0044] In order to solve the problems existing in the prior art, the embodiment of the present invention provides a combined analysis method of iron-55 and nickel-63 in urine samples. After the urine sample is oxidized with hydrogen peroxide and co-precipitated with sodium hydroxide, an anion exchange resin is used in combination with dimethylglyoxime precipitation to separate and purify the iron-55 and nickel-63 in the sample. 55 Fe and 63 Ni, purified 55 Fe and 63 Ni is measured using a liquid scintillation counter (LSC). 55 Fe, 63 Ni two radionuclides, a set of 8 samples can be completed within 5 hours 55 Fe and 63 The radiochemical separation process of Ni greatly improves the sample processing efficiency and reduces the time required for radiochemical separation of samples.

[0045] Example 1

[0046] Add 200mL of urine sample 55 Fe standard solution 39.6Bq, 63 Ni standard solution 35.3Bq, the urine is used as the test solution, the sample is pre-treated and radiochemically separated by the method of the present invention, and the separated 55 Fe and 63 Ni was measured by LSC and the method was validated for 55 Fe and 63 Separation effect of Ni, measurement of detection limit and recovery rate.

[0047] like Figure 1 As shown, a combined analysis method for iron-55 and nickel-63 in urine samples comprises the following steps:

[0048] S1: Urine sample pretreatment

[0049] Add 2 mL of 12 mol / L concentrated hydrochloric acid, 5 mg Fe 3+ and 2mgNi 2+, 0.2mL of 30% H2O2, heated at 100℃ for 10min, added sodium hydroxide (NaOH) solid particles to adjust the sample pH to 8-10, stirred for 20min, Fe(OH)3-Ni(OH)2 co-precipitate was generated, centrifuged, the supernatant was discarded, the precipitate was washed with high-purity water, dissolved with 10.0mL of 12mol / L HCl, and high-purity water was added to a total volume of 13.3mL, the system was adjusted to 9mol / L HCl, marked as sample dissolving solution.

[0050] S2: Radiochemical separation and measurement of samples

[0051] 2 mL of resin column was filled with AGMP-1 anion exchange resin, and pretreated with 9 mol / L HCl before use;

[0052] The sample solution was passed through the AGMP-1 anion exchange resin column at a flow rate of 2 mL / min, and the effluent was collected and marked as the Ni component. Then, the anion exchange resin column was eluted with 60 mL 12 mol / L HCl at a flow rate of 2 mL / min and 8 mL 6 mol / L HCl at a flow rate of 1 mL / min. After the elution was completed, Fe was eluted with 3 mL 0.1 mol / L HCl at a flow rate of 2 mL / min, and the retained eluent was marked as 55 Fe test solution, iron recovery rate was measured by X-ray fluorescence spectrometer (XRF), and iron recovery rate was measured by liquid scintillation counter (LSC) 55 Fe activity.

[0053] S3: Separation and measurement of Ni components

[0054] Add 0.2 mL of 2% (w / v) citric acid and 2.5 mL of 1% (w / v) dimethylglyoxime (DMG) ethanol solution to the Ni component, add ammonia water to adjust the pH to 8-10, generate bright red DMG-Ni precipitate, centrifuge, discard the supernatant, wash the precipitate with high-purity water, add 0.3 mL of 12 mol / L HCl, let stand for 10 min, centrifuge, discard the trace insoluble matter, retain the supernatant, and mark it as 63 Ni test solution, nickel recovery rate measured by XRF, LSC measurement 63 Your activity.

[0055] S4: Measurement results

[0056] The method in this embodiment is used to separate and purify the 55 Fe and 63 The measurement results of Ni, recovery rate (R) and minimum detection limit (MDC) are shown in Table 1. MDC is calculated according to formula (1):

[0057]

[0058] Where k is the coverage factor, which is 1.645 (95% confidence level); B is the blank sample measured by LSC. 55 Fe or 63 Ni is the counts in the corresponding energy range; ε is the LSC measurement efficiency; R is the recovery rate of iron or nickel; t is the measurement time; v is the sample volume.

[0059] The internal radiation dose calculation software GenmodPC was used to simulate and calculate that in emergency situations, when the accumulated effective dose is 1mSv, 55 Fe inhalation was 21 Bq / g in urine after 2 days and 3.62 Bq / g in urine after 1 month. 63 After inhalation of Ni, the urine level was 7937 Bq / L after 2 days and 298 Bq / L after 1 month.

[0060] The detection limit of the combined process analysis method of the present invention meets the requirements of human urine excretion in emergency situations. 55 Fe and 63 Your measurement needs. 55 Fe and 63 The LSC measurement spectrum of Ni is as follows Figure 2 , Figure 3 As shown in the spectrum, after the combined separation process, 55 Fe and 63 Ni achieved a very good separation effect.

[0061] Table 1 55 Fe and 63 Recovery rate and minimum detection limit of Ni

[0062] Nuclide R(％) MDC(Bq / L) <![CDATA[ 55 Fe]]> 98.3 1.5 <![CDATA[ 63 In]]> 73.5 0.5

[0063] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation modes, which are merely illustrative rather than restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the present invention and the claims, all of which are within the protection of the present invention.

Claims

1. A combined analysis method for iron-55 and nickel-63 in urine samples, characterized in that: The following steps are involved: S1: Urine sample pretreatment Add concentrated hydrochloric acid, Fe 3+ 、Ni 2+ and hydrogen peroxide, after heating, adjust the pH to alkaline with solid sodium hydroxide, stir, centrifuge the sample, discard the supernatant, wash the precipitate, and dissolve it with concentrated hydrochloric acid to obtain a sample solution; S2: Radiochemical separation of samples Fill the resin column with anion exchange resin, pre-treat it with hydrochloric acid, and set it aside; The sample solution was passed through an anion exchange resin, and the effluent was collected and labeled as the Ni component; The anion exchange resin was washed with 12 mol / L HCl and 6 mol / L HCl in sequence. After washing, the anion exchange resin was eluted with 0.1 mol / L HCl. The eluent was marked as 55 Fe test solution, measure the recovery rate of iron and 55 Fe activity; S3: Separation and measurement of Ni components Add citric acid and dimethylglyoxime ethanol solution to the effluent, adjust the pH to alkaline with ammonia water, generate a precipitate, centrifuge, discard the supernatant, wash the precipitate, dissolve it with concentrated hydrochloric acid, centrifuge, discard the trace insoluble matter, retain the supernatant and mark it as 63 Ni test solution, measure the nickel recovery and 63 Your activity.

2. The combined analysis method of iron-55 and nickel-63 in urine samples according to claim 1, characterized in that: In step S1, 5‰ to 5% (v / v) 12 mol / L concentrated hydrochloric acid, 2 to 10 mg Fe 3+ , 2~5mg Ni 2+ and 1‰~1% (v / v) 30% hydrogen peroxide.

3. The combined analysis method of iron-55 and nickel-63 in urine samples according to claim 1, characterized in that: In step S1, the heating temperature is 70-120° C. and the heating time is 8-12 min. The pH is adjusted to 8-10 with solid sodium hydroxide, and the mixture is stirred for 10-30 min before centrifugation.

4. The combined analysis method of iron-55 and nickel-63 in urine according to claim 1, characterized in that: In step S1, after dissolving with 12 mol / L concentrated hydrochloric acid, the system is adjusted to 9 mol / L HCl with high-purity water.

5. The combined analysis method of iron-55 and nickel-63 in urine samples according to claim 1, characterized in that: In step S2, an anion exchange resin is loaded into a 2 mL resin column, pretreated with 9 mol / L HCl, and then set aside.

6. The combined analysis method of iron-55 and nickel-63 in urine samples according to claim 1, characterized in that: In step S2, the sample solution is passed through an anion exchange resin column at a flow rate of 0.5 to 3 mL / min.

7. The combined analysis method of iron-55 and nickel-63 in urine samples according to claim 1, characterized in that: In step S2, the anion exchange resin column is eluted with 20 to 40 column volumes of 12 mol / L HCl at a flow rate of (0.5 to 3) mL / min and 3 to 5 column volumes of 6 mol / L HCl at a flow rate of (0.5 to 3) mL / min, respectively. After elution, it is eluted with 1 to 3 column volumes of 0.1 mol / L HCl at a flow rate of (0.5 to 3) mL / min.

8. The combined analysis method of iron-55 and nickel-63 in urine samples according to claim 1, characterized in that: In step S2, the method for measuring the iron recovery rate is one of an inductively coupled plasma atomic emission spectrometer, an ultraviolet spectrophotometer or an X-ray fluorescence spectrometer; 55 The Fe activity was measured using a liquid scintillation counter.

9. The combined analysis method of iron-55 and nickel-63 in urine samples according to claim 1, characterized in that: In step S3, 0.2 mL of 2% (w / v) citric acid and 2-5 mL of 1% (w / v) dimethylglyoxime ethanol solution are added to the effluent, and aqueous ammonia is added to adjust the pH to 8-10.

10. The combined analysis method of iron-55 and nickel-63 in urine samples according to claim 1, characterized in that: In step S3, the method for measuring the nickel recovery rate is one of an inductively coupled plasma atomic emission spectrometer, an ultraviolet spectrophotometer or an X-ray fluorescence spectrometer. 63 The Ni activity was measured using a liquid scintillation counter.

Images