A method for analyzing trace elements in urine

Abstract

The invention discloses an analysis method for trace elements in urine, and relates to the technical field of analysis of trace elements in urine; the invention comprises the following steps: S1: collecting urine samples of healthy volunteers with a clean urine collection device, adding concentrated nitric acid at a ratio of 100:1, adjusting pH value to ≤2, and freezing and storing at -18°C; S2: before experimental determination, placing the urine sample at room temperature for natural thawing, and mixing and homogenizing with a vortex mixer; the invention establishes a direct dilution -iCRC-ICP-MS method for determining 14 trace elements in human urine samples, adopts a collision reaction mode to remove polyatomic ions, effectively suppresses mass spectrum interference in the sample determination process, and adds multiple internal standard elements online to correct matrix effects for different analysis elements, so that the determination results are more accurate; due to the low content of trace elements in urine, 5% by volume of isopropanol is used as a sensitizer, which greatly improves the detection sensitivity.

Description

Technical Field

[0001] The invention relates to the technical field of analysis of trace elements in urine, and in particular to a method for analyzing trace elements in urine. Background Art

[0002] The content of trace elements in the human body is closely related to health. Excessive intake or excessive excretion will cause adverse effects or diseases to human health. Urine sampling is simple, with a large sample size and is non-destructive. Many trace elements are excreted from urine in their original or metabolite forms, which is suitable for monitoring the metabolism and secretion of trace elements in the human body. Therefore, accurate quantification of the content of trace elements in urine is of great significance for finding disease prevention or clinical treatment strategies. ICP-MS can accurately quantify multiple elements in a sample at the same time, and has the advantages of high sensitivity, low detection limit and wide dynamic linear range. It is currently preferred for the analysis of biological samples such as serum, urine and hair.

[0003] The prior art has the following problems:

[0004] Due to the low content of trace elements in urine, the existing analysis method for trace elements in urine has low detection sensitivity. At the same time, the method has a high detection limit, low sensitivity, and is not convenient to operate. It is not suitable for the detection of trace elements in large quantities of clinical urine samples. In response to the above problems, the inventors propose an analysis method for trace elements in urine to solve the above problems. Summary of the invention

[0005] In order to solve the problems that the existing analysis method for trace elements in urine has low detection sensitivity, high detection limit, low sensitivity and inconvenient operation; the purpose of the present invention is to provide an analysis method for trace elements in urine.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solution: a method for analyzing trace elements in urine, comprising the following steps:

[0007] S1: Collect urine samples from healthy volunteers using a clean urine collection device, add concentrated nitric acid at a ratio of 100:1, adjust the pH to ≤ 2, and freeze at -18°C;

[0008] S2: Before the experimental determination, the urine samples were thawed naturally at room temperature and mixed with a vortex mixer;

[0009] S3: Use the weight method to add a certain amount of urine sample to the diluent and dilute it 10 times quantitatively, and use a vortex mixer to mix it for testing;

[0010] S4: Use semi-quantitative analysis methods to conduct preliminary determination of the elements to be detected in urine;

[0011] S5: The instrument was tuned and calibrated using 1 μg / L mass spectrometer tuning solution and 10 μg / L isopropanol spiked solution, and the conditions with maximum sensitivity, minimum oxide yield and double charge yield were selected by performing orthogonal experiments on important parameters such as RF power, nebulizer flow rate and injection speed;

[0012] S6: Urine samples contain high-salt matrix, which will cause matrix effect and instrument signal drift during the analysis process, affecting the accuracy and stability of the measurement results, and the internal standard method needs to be used for correction. Commonly used internal standard elements include 45Sc, 103Rh, 115In, 185Re, 209Bi, etc. Since the urine sample contains a small amount of 45Sc and 209Bi, three mixed internal standard elements of 103Rh, 115In and 185Re are selected to calibrate the analytical elements separately. Use a Y-type three-way valve to add 50μg / L internal standard mixed solution to the sample in a 1:1 ratio online;

[0013] S7: Use 1% (v / v) HNO3 solution to make up to volume, prepare 10μg / L isopropanol spiked solution with a volume fraction of 0% to 6% (v / v), and use the sensitivity enhancement coefficient (RSI) to examine its effect on the signal intensity of the measured elements. When the volume fraction is 5%, the sensitization effect of all elements reaches the strongest, and the signal value of the elements in pure water is enhanced by 1.5 to 10 times, and then it shows a downward trend. Finally, 5% (v / v) isopropanol was added to 1% HNO3 as the diluent;

[0014] S8: Under optimized instrument conditions, the diluent was used as the blank solution and the measurement was repeated 10 times independently. The detection limit and quantification limit were calculated with the concentrations corresponding to 3 times and 10 times the standard deviation of the measured value, respectively. The detection limit of each element was 0.0008-0.4418 μg / L, and the quantification limit was 0.0028-1.4727 μg / L. The 17 trace elements showed a good linear relationship within the working range of the standard curve, and the correlation coefficient R2 was greater than 0.999, which met the analysis requirements of trace elements in urine.

[0015] Preferably, the diluent in S3 is 1% HNO3-5% isopropanol solution, and the concentration ranges of the elements in S4 in the standard curve are as follows: 0.05, 0.1, 0.5, 1, 2 μg / L for Cr, Mn, Co, Ni, Cd, Cs, Ba, Tl and Pb; 0.5, 1, 2, 5, 10 μg / L for Li, Al, Fe, Cu, As and Se; 5, 10, 20, 50, 100 μg / L for Zn and Sr, and 103Rh in S6 is used to correct Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se and Sr; 115In is used to correct Cd, Cs and Ba; 185Re is used to correct Tl and Pb.

[0016] Preferably, in S1, the urine collection device includes a urine collection bottle, a sealing cover is provided on the upper movable sleeve of the urine collection bottle, an outer wall of the sealing cover is fixedly connected with an air outlet pipe connected to the interior of the sealing cover, an upper end face of the sealing cover is fixedly connected with a motor, an inner cavity of the mounting cover is fixedly connected with a sealing box, a grid plate is fixedly connected at the bottom of the inner cavity of the mounting cover, a support frame is fixedly connected to one side of the inner cavity of the mounting cover, a rotating rod is rotatably connected inside the support frame, a fan blade is fixedly connected to one end of the rotating rod, a glass stirring rod is provided inside the urine collection bottle, a first bevel gear is rotatably connected to one side of the interior of the sealing box, a second bevel gear meshing with the first bevel gear is rotatably connected to the upper part of the interior of the sealing box, and a third bevel gear meshing with the first bevel gear is rotatably connected to the lower part of the interior of the sealing box.

[0017] Preferably, a scale bar is fixedly connected to the outer wall of the urine collection bottle, a sealing flip plate is provided on the outer wall of the air outlet pipe, and a rotating shaft is fixedly connected between the sealing flip plate and the air outlet pipe.

[0018] Preferably, a feed pipe is fixedly inserted on one side of the upper end surface of the sealing cover, a threaded sleeve is fixedly connected to the upper end surface of the feed pipe, a mounting cover is rotatably connected to the outer wall of the threaded sleeve, a plug hole is penetrated through one side of the interior of the grid plate, the lower end of the feed pipe extends into the interior of the plug hole, a glass stirring blade is fixedly connected to the lower end surface of the glass stirring rod, and the fan blade is located inside the exhaust pipe.

[0019] Preferably, the output end of the motor extends to the interior of the sealed box and is fixedly connected to the second bevel gear, one end of the rotating rod extends to the interior of the sealed box and is fixedly connected to the first bevel gear, the upper end of the glass stirring rod passes through the grid plate and extends to the interior of the sealed box and is fixedly connected to the third bevel gear.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The present invention establishes a direct dilution-iCRC-ICP-MS method for determining 14 trace elements in human urine samples. The collision reaction mode is used to remove polyatomic ions, which effectively suppresses the mass spectrometry interference in the sample determination process. For different analytical elements, multiple internal standard elements are added online to correct the matrix effect, so that the determination results are more accurate. Due to the low content of trace elements in urine, 5% volume fraction of isopropanol is used as a sensitizer, which greatly improves the detection sensitivity. The detection results of elements determined by human urine standard substances are consistent with the standard reference values. The method has a low detection limit, high sensitivity, and convenient operation, and is suitable for the detection of trace elements in large quantities of clinical urine samples;

[0022] 2. The first bevel gear, the second bevel gear and the third bevel gear are installed by rotating inside the sealed box. The motor drives the output end to rotate, and the rotation of the output end drives the second bevel gear inside the sealed box to rotate. Since the second bevel gear and the first bevel gear are meshed with each other, and the first bevel gear and the third bevel gear are meshed with each other, the rotation of the second bevel gear drives the first bevel gear to rotate, and the rotation of the first bevel gear drives the third bevel gear to rotate. The rotation of the third bevel gear drives the glass stirring rod and the glass stirring blade to rotate at the same time. The rotation of the glass stirring blade fully blends the urine sample with concentrated nitric acid and releases a large amount of heat at the same time. The rotation of the first bevel gear drives the rotating rod and the fan blade to rotate at the same time. The rotation of the fan blade discharges the heat and the output exhaust gas, speeds up the cooling speed, prevents high temperature from burning the staff, and greatly improves the use effect of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0025] Figure 2 The figure is a schematic diagram of the internal structure of the urine collection bottle of the present invention.

[0026] Figure 3 It is a schematic diagram of the internal structure of the sealing box of the present invention.

[0027] In the figure: 1. urine collection bottle; 2. scale bar; 3. sealing cover; 4. air outlet pipe; 5. sealing flip plate; 6. rotating shaft; 7. motor; 8. feed pipe; 9. installation cover; 10. threaded sleeve; 11. sealing box; 12. support frame; 13. rotating rod; 14. fan blade; 15. glass stirring rod; 16. glass sheet stirring blade; 17. grid plate; 18. jack; 19. first bevel gear; 20. second bevel gear; 21. third bevel gear. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] Example: Figure 1-3As shown, the present invention provides a technical solution: a method for analyzing trace elements in urine, comprising the following steps:

[0030] S1: Collect urine samples from healthy volunteers using a clean urine collection device, add concentrated nitric acid at a ratio of 100:1, adjust the pH to ≤ 2, and freeze at -18°C;

[0031] S2: Before the experimental determination, the urine samples were thawed naturally at room temperature and mixed with a vortex mixer;

[0032] S3: Use the weight method to add a certain amount of urine sample to the diluent (1% HNO3-5% isopropanol solution) and dilute it 10 times quantitatively, and use a vortex mixer to mix it for testing;

[0033] S4: A semi-quantitative analysis method was used to preliminarily determine the elements to be detected in urine. The concentration ranges of the elements in the standard curve were as follows: 0.05, 0.1, 0.5, 1, 2 μg / L for Cr, Mn, Co, Ni, Cd, Cs, Ba, Tl and Pb; 0.5, 1, 2, 5, 10 μg / L for Li, Al, Fe, Cu, As and Se; 5, 10, 20, 50, 100 μg / L for Zn and Sr;

[0034] S5: The instrument was tuned and calibrated using 1 μg / L mass spectrometer tuning solution and 10 μg / L isopropanol spiked solution, and the conditions with maximum sensitivity, minimum oxide yield and double charge yield were selected by performing orthogonal experiments on important parameters such as RF power, nebulizer flow rate and injection speed;

[0035] The polyatomic ion interference formed by the combination of Ar ions introduced by the plasma and C, H, O, N, and C1 contained in the urine sample affects the accuracy of the test results, such as 12C15N+ interfering with 27Al, 40Ar12C+ interfering with 52Cr, 40Ar16O+ interfering with 56Fe, 40Ar38Ar+ interfering with 78Se, etc. This experiment uses an integrated collision reaction cell technology, which can effectively reduce the interference of polyatomic ions by introducing collision gas He and reaction gas H2 in the interceptor cone. Fix the other working parameters of the instrument, adjust the collision reaction gas flow rate in the range of 0 to 160 mL / min with a step size of 20 mL / min, and scan the 10 μg / L standard solution and standard blank. Use background equivalent concentration (BEC) and signal-to-background ratio (S / B) as optimization evaluation indicators;

[0036] S6: Urine samples contain high-salt matrix, which will cause matrix effect and instrument signal drift during the analysis process, affecting the accuracy and stability of the measurement results, and the internal standard method needs to be used for correction. Commonly used internal standard elements include 45Sc, 103Rh, 115In, 185Re, 209Bi, etc. Since the urine sample contains a small amount of 45Sc and 209Bi, three mixed internal standard elements of 103Rh, 115In and 185Re are selected to calibrate the analyzed elements separately (103Rh calibrates Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se and Sr; 115In calibrates Cd, Cs and Ba; 185Re calibrates Tl and Pb). Use a Y-type three-way valve to add 50μg / L internal standard mixed solution and sample online in a 1:1 ratio;

[0037] S7: Use 1% (v / v) HNO3 solution to make up to volume, prepare 10μg / L isopropanol spiked solution with a volume fraction of 0% to 6% (v / v), and use the sensitivity enhancement coefficient (RSI) to examine its effect on the signal intensity of the measured elements. When the volume fraction is 5%, the sensitization effect of all elements reaches the strongest, and the signal value of the elements in pure water is enhanced by 1.5 to 10 times, and then it shows a downward trend. Finally, 5% (v / v) isopropanol was added to 1% HNO3 as the diluent;

[0038] S8: Under optimized instrument conditions, the diluent was used as the blank solution and the measurement was repeated 10 times independently. The detection limit and quantification limit were calculated with the concentrations corresponding to 3 times and 10 times the standard deviation of the measured value, respectively. The detection limit of each element was 0.0008-0.4418 μg / L, and the quantification limit was 0.0028-1.4727 μg / L. The 17 trace elements showed a good linear relationship within the working range of the standard curve, and the correlation coefficient R2 was greater than 0.999, which met the analysis requirements of trace elements in urine.

[0039] In S1, the urine collection device includes a urine collection bottle 1, a sealing cover 3 is provided on the upper movable sleeve of the urine collection bottle 1, an outer wall of the sealing cover 3 is fixedly connected with an air outlet pipe 4 connected to the inside of the sealing cover 3, an upper end face of the sealing cover 3 is fixedly connected with a motor 7, an inner cavity of the mounting cover 9 is fixedly connected with a sealing box 11, a mesh plate 17 is fixedly connected at the bottom of the inner cavity of the mounting cover 9, which plays a good isolation role, a support frame 12 is fixedly connected to one side of the inner cavity of the mounting cover 9, a rotating rod 13 is rotatably connected inside the support frame 12, a fan blade 14 is fixedly connected to one end of the rotating rod 13, a glass stirring rod 15 is provided inside the urine collection bottle 1, a first bevel gear 19 is rotatably connected to one side of the inside of the sealing box 11, a second bevel gear 20 meshing with the first bevel gear 19 is rotatably connected at the top of the inside of the sealing box 11, and a third bevel gear 21 meshing with the first bevel gear 19 is rotatably connected at the bottom of the inside of the sealing box 11.

[0040] A scale bar 2 is fixedly connected to the outer wall of the urine collection bottle 1, a sealing flip plate 5 is provided on the outer wall of the air outlet pipe 4, a rotating shaft 6 is fixedly connected between the sealing flip plate 5 and the air outlet pipe 4, a feed pipe 8 is fixedly inserted on one side of the upper end surface of the sealing cover 3, a threaded sleeve 10 is fixedly connected to the upper end surface of the feed pipe 8, and a mounting cover 9 is rotatably connected to the outer wall of the threaded sleeve 10.

[0041] By adopting the above technical solution, both the mounting cover 9 and the sealing flip plate 5 play a good sealing role.

[0042] A plug hole 18 is penetrated on one side of the mesh plate 17, and the lower end of the feed pipe 8 extends into the inside of the plug hole 18. The lower end face of the glass stirring rod 15 is fixedly connected to a glass sheet stirring blade 16. The fan blade 14 is located inside the air outlet pipe 4, and the output end of the motor 7 extends to the inside of the sealing box 11 and is fixedly connected to the second bevel gear 20. One end of the rotating rod 13 extends to the inside of the sealing box 11 and is fixedly connected to the first bevel gear 19. The upper end of the glass stirring rod 15 penetrates the mesh plate 17 and extends to the inside of the sealing box 11, and is fixedly connected to the third bevel gear 21.

[0043] By adopting the above technical solution, the motor 7 drives the output end to rotate, and the rotation of the output end drives the second bevel gear 20 inside the sealing box 11 to rotate. Since the second bevel gear 20 is meshed with the first bevel gear 19, and the first bevel gear 19 is meshed with the third bevel gear 21, the rotation of the second bevel gear 20 drives the first bevel gear 19 to rotate, and the rotation of the first bevel gear 19 drives the third bevel gear 21 to rotate. The rotation of the third bevel gear 21 drives the glass stirring rod 15 and the glass sheet stirring blade 16 to rotate at the same time. The rotation of the glass sheet stirring blade 16 fully blends the urine sample with concentrated nitric acid and releases a large amount of heat. The rotation of the first bevel gear 19 drives the rotating rod 13 and the fan blade 14 to rotate at the same time. The rotation of the fan blade 14 discharges the heat and the output exhaust gas, accelerates the cooling speed, prevents high temperature from burning the staff, and greatly improves the use effect of the device.

[0044] Working principle: Use a clean urine collection bottle 1 to collect urine samples from healthy volunteers, install the sealing cover 3 on the urine collection bottle 1, pour concentrated nitric acid into the urine collection bottle 1 through the feeding pipe 8 at a ratio of 100:1, adjust the pH value to 2, start the motor 7 on the sealing cover 3, the motor 7 drives the output end to rotate, and the output end rotates to drive the second bevel gear 20 inside the sealing box 11 to rotate. Since the second bevel gear 20 is meshed with the first bevel gear 19, and the first bevel gear 19 is meshed with the third bevel gear 21, the second bevel gear 20 is meshed with the first bevel gear 19. The rotation of the gear 20 drives the first bevel gear 19 to rotate, the rotation of the first bevel gear 19 drives the third bevel gear 21 to rotate, the rotation of the third bevel gear 21 drives the glass stirring rod 15 and the glass stirring blade 16 to rotate simultaneously, the glass stirring blade 16 rotates to fully fuse the urine sample with concentrated nitric acid, and releases a large amount of heat at the same time, the rotation of the first bevel gear 19 drives the rotating rod 13 and the fan blade 14 to rotate simultaneously, the fan blade 14 rotates to discharge the heat and the produced waste gas, speeding up the cooling speed, and then the urine collection bottle 1 is frozen and stored at -18°C;

[0045] Before the experimental determination, the urine samples were thawed naturally at room temperature, mixed and homogenized using a vortex mixer, and a certain amount of urine samples were added to the diluent (1% HNO3-5% isopropanol solution) by weight method to quantitatively dilute 10 times, and mixed and homogenized using a vortex mixer. The elements to be detected in urine were preliminarily determined using a semi-quantitative analysis method. The concentration ranges of each element in the standard curve are as follows: Cr, Mn, Co, Ni, Cd, Cs, Ba, Tl and Pb are 0.05, 0.1, 0.5, 1, 2 μg / L; Li, Al, Fe, Cu, As and Se are 0.5, 1, 2, 5, 10 μg / L; Zn and Sr are 5, 10, 20, 50, 100 μg / L;

[0046] The instrument was tuned and calibrated using 1 μg / L mass spectrometer tuning solution and 10 μg / L isopropanol spiked solution, and orthogonal experiments were performed on important parameters such as RF power, nebulizer flow rate, and injection speed to select conditions that maximized sensitivity and minimized oxide and double charge yields;

[0047] The polyatomic ion interference formed by the combination of Ar ions introduced by the plasma and C, H, O, N, and C1 contained in the urine sample affects the accuracy of the test results, such as 12C15N+ interfering with 27Al, 40Ar12C+ interfering with 52Cr, 40Ar16O+ interfering with 56Fe, 40Ar38Ar+ interfering with 78Se, etc. This experiment uses an integrated collision reaction cell technology, which can effectively reduce the interference of polyatomic ions by introducing collision gas He and reaction gas H2 in the interceptor cone. Fix the other working parameters of the instrument, adjust the collision reaction gas flow rate in the range of 0 to 160 mL / min with a step size of 20 mL / min, and scan the 10 μg / L standard solution and standard blank. Use background equivalent concentration (BEC) and signal-to-background ratio (S / B) as optimization evaluation indicators;

[0048] Urine samples contain high-salt matrix, which will cause matrix effect and instrument signal drift during the analysis process, affecting the accuracy and stability of the measurement results. Internal standard method must be used for correction;

[0049] Commonly used internal standard elements include 45Sc, 103Rh, 115In, 185Re, 209Bi, etc. Since urine samples contain a small amount of 45Sc and 209Bi, three mixed internal standard elements of 103Rh, 115In and 185Re are selected to calibrate the analyzed elements respectively (103Rh calibrates Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se and Sr; 115In calibrates Cd, Cs and Ba; 185Re calibrates Tl and Pb). Use a Y-type three-way valve to add 50μg / L internal standard mixed solution and sample online at a ratio of 1:1;

[0050] Use 1% (v / v) HNO3 solution to make up to volume, prepare 10μg / L isopropanol spiked solution with volume fraction of 0% to 6% (v / v), and use the sensitivity enhancement coefficient (RSI) to examine its effect on the signal intensity of the measured elements. When the volume fraction is 5%, the sensitization effect of all elements reaches the strongest, and the signal value of the elements in pure water is enhanced by 1.5 to 10 times, and then it shows a downward trend. Finally, add 5% (v / v) isopropanol to 1% HNO3 as the diluent;

[0051] Under the optimized instrument conditions, the diluent was used as the blank solution, and the measurement was repeated 10 times independently. The detection limit and quantification limit were calculated with the concentrations corresponding to 3 times and 10 times the standard deviation of the measured value, respectively. The detection limit of each element was 0.0008-0.4418μg / L, and the quantification limit was 0.0028-1.4727μg / L. The 17 trace elements showed a good linear relationship within the working range of the standard curve, and the correlation coefficient R2 was greater than 0.999, which met the analysis requirements of trace elements in urine.

[0052] Mixed urine from multiple people was collected, and a certain volume of standard solution with different concentrations was added. The test was repeated 6 times independently within one day, and the spiked recovery and relative standard deviation of the measured elements were calculated. The spiked recovery of the measured elements was between 83.6% and 110.5%, and the precision was less than 5%, indicating that this method was stable and reliable for the quantitative analysis of actual urine samples.

[0053] This method was used to determine the urine standard material Seronorm Trace Elements Urine L-1 / L-2, and the measured values ​​of each element were within the reference value range, indicating that this method can meet the requirements for accurate quantification of trace elements in urine samples.

[0054] This method was used to determine 17 trace elements in urine samples from 30 healthy volunteers. Each sample was measured three times in parallel and the average value was taken.

[0055] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for analyzing trace elements in urine, characterized in that: The following steps are involved: S1: Collect urine samples from healthy volunteers using a clean urine collection device, add concentrated nitric acid, adjust the pH to ≤ 2, and freeze at -18°C; S2: Before the experimental determination, the urine samples were thawed naturally at room temperature and mixed with a vortex mixer; S3: Use the weight method to add a certain amount of urine sample to the diluent and dilute it 10 times quantitatively, and use a vortex mixer to mix it for testing; S4: A semi-quantitative analysis method was used to preliminarily determine the elements to be detected in urine. The concentration ranges of the elements in the standard curve were as follows: 0.05, 0.1, 0.5, 1, and 2 μg / L for Cr, Mn, Co, Ni, Cd, Cs, Ba, Tl, and Pb; 0.5, 1, 2, 5, and 10 μg / L for Li, Al, Fe, Cu, As, and Se; and 5, 10, 20, 50, and 100 μg / L for Zn and Sr. S5: The instrument was tuned and calibrated using 1 μg / L mass spectrometer tuning solution and 10 μg / L isopropanol spike solution, and the conditions with maximum sensitivity, minimum oxide yield and double charge yield were selected by orthogonal experiments on RF power, nebulizer flow rate and injection speed; S6: Urine samples contain high-salt matrix, which will cause matrix effect and instrument signal drift during the analysis process, affecting the accuracy and stability of the measurement results. Internal standard method is required for correction. Therefore, three mixed internal standard elements, 103Rh, 115In and 185Re, are selected to calibrate the analyzed elements respectively. A Y-type three-way valve is used to add 50μg / L internal standard mixed solution to the sample in a 1:1 ratio online. 103Rh is used to calibrate Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se and Sr; 115In is used to calibrate Cd, Cs and Ba; 185Re is used to calibrate Tl and Pb. S7: Use 1% v / v HNO3 solution to make up to volume, prepare 10μg / L isopropanol spiked solution with a volume fraction of 0% to 6%, and use the sensitivity enhancement coefficient to examine its effect on the signal intensity of the measured elements. When the volume fraction of isopropanol added is 5%, the sensitization effect of all elements reaches the strongest, and the signal value of the elements in pure water is enhanced by 1.5 to 10 times, and then it shows a downward trend. Finally, 5% volume fraction of isopropanol is added to 1% v / v HNO3 as the diluent; S8: Under optimized instrument conditions, the diluent was used as the blank solution and the measurement was repeated 10 times independently. The detection limit and quantification limit were calculated with the concentrations corresponding to 3 times and 10 times the standard deviation of the measured value, respectively. The detection limit of each element was 0.0008~0.4418μg / L, and the quantification limit was 0.0028~1.4727μg / L. The 17 trace elements showed a good linear relationship within the working range of the standard curve, and the correlation coefficient R2 was greater than 0.999, which met the analysis requirements of trace elements in urine.

2. The method for analyzing trace elements in urine according to claim 1, characterized in that: In S1, the urine collection device comprises a urine collection bottle (1), the upper movable sleeve of the urine collection bottle (1) is provided with a sealing cover (3), the outer wall of the sealing cover (3) is fixedly connected to an air outlet pipe (4) which is connected to the inside of the sealing cover (3), the upper end surface of the sealing cover (3) is fixedly connected to a motor (7), a feed pipe (8) is fixedly plugged into one side of the upper end surface of the sealing cover (3), the upper end surface of the feed pipe (8) is fixedly connected to a threaded sleeve (10), the outer wall of the threaded sleeve (10) is rotatably connected to a mounting cover (9), the inner cavity of the mounting cover (9) is fixedly connected to a sealing box (11), and the lower part of the inner cavity of the mounting cover (9) is fixedly connected to a mesh. A grid plate (17), one side of the inner cavity of the mounting cover (9) is fixedly connected to a support frame (12), the interior of the support frame (12) is rotatably connected to a rotating rod (13), one end of the rotating rod (13) is fixedly connected to a fan blade (14), a glass stirring rod (15) is provided inside the urine collection bottle (1), one side of the interior of the sealing box (11) is rotatably connected to a first bevel gear (19), the upper part of the interior of the sealing box (11) is rotatably connected to a second bevel gear (20) meshing with the first bevel gear (19), and the lower part of the interior of the sealing box (11) is rotatably connected to a third bevel gear (21) meshing with the first bevel gear (19).

3. The method for analyzing trace elements in urine according to claim 2, characterized in that: The outer wall of the urine collection bottle (1) is fixedly connected to a scale bar (2), the outer wall of the air outlet pipe (4) is provided with a sealing flip plate (5), and a rotating shaft (6) is fixedly connected between the sealing flip plate (5) and the air outlet pipe (4).

4. The method for analyzing trace elements in urine according to claim 2, characterized in that: An insertion hole (18) is provided through one side of the mesh plate (17), and the lower end of the feed pipe (8) extends into the insertion hole (18).

5. The method for analyzing trace elements in urine according to claim 2, characterized in that: The lower end surface of the glass stirring rod (15) is fixedly connected to a glass sheet stirring blade (16), and the fan blade (14) is located inside the air outlet pipe (4).

6. The method for analyzing trace elements in urine according to claim 2, characterized in that: The output end of the motor (7) extends into the interior of the sealed box (11) and is fixedly connected to the second bevel gear (20); one end of the rotating rod (13) extends into the interior of the sealed box (11) and is fixedly connected to the first bevel gear (19); the upper end of the glass stirring rod (15) passes through the grid plate (17) and extends into the interior of the sealed box (11) and is fixedly connected to the third bevel gear (21).

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