Keel element fingerprint spectrum construction and authenticity identification method based on ICP-MS / EDXRF combination

Abstract

The invention provides a dragon bone element fingerprint construction and authenticity identification method based on ICP-MS / EDXRF combination, and belongs to the crossing field of a spectrum analysis technology and traditional Chinese medicine quality control. The method comprises the following steps: firstly, scanning all mass numbers with m / z of 7-238 on keels by utilizing ICP-MS (Inductively Coupled Plasma Mass Spectrometry), screening and quantifying 15 elements with relatively large content difference in different types of keels, and establishing element contrast fingerprints of genuine and counterfeit keels with different colors; carrying out semi-quantitative analysis on elements at different parts of the keel by combining the nondestructive testing characteristics of EDXRF, and carrying out supplementary analysis on elements which are not suitable for measurement or have relatively large interference in ICP-MS (Inductively Coupled Plasma Mass Spectrometry); by comparing the ICP-MS analysis result of the to-be-detected dragon bone with the control fingerprint spectrum and combining the EDXRF measurement result, the authenticity of the dragon bone and the identification of different counterfeit product types are realized. The method has the beneficial effects that keels with different colors and various counterfeit products can be effectively distinguished, simultaneous detection of multiple elements is realized, and a scientific and objective method is provided for keel quality control.

Description

TECHNICAL FIELD

[0001] The present application mainly relates to the technical field of spectral analysis technology and traditional Chinese medicine quality control, and particularly relates to a method for constructing an element fingerprint of dragon bone and identifying authenticity based on ICP-MS / EDXRF combination. BACKGROUND

[0002] Dragon bone Os Draconis In the Shenglong Bencaojing, it is listed as the top product, and is the fossil of large lactation animals such as three-toed horses, bovine, elephant and rhinoceros in ancient times. The quality research basis of dragon bone is relatively weak, and the clinical application is still mainly based on experience. In ancient books such as Bencaojing Jizhu, Leigong Paozhi Lun and Xinxiu Bencaojing, the quality is divided by color, and it is considered that the best is five colors, the white color is better, and the black color is the worst. The modern description of five-flower dragon bone is light yellow white, light gray white or light brown, with blue black, blue gray and red brown patterns of different depths and thicknesses. The blue black or blue gray pattern is commonly known as “dragon bone spot”, and the formation of the red brown spot on the dragon bone is due to the penetration of minerals or soil and the reaction with calcium in the bone. The quality difference of different colors of dragon bone and its element connotation still need to be further explained combined with modern research.

[0003] As a fossil of ancient organisms, dragon bone is buried in the ground for many years, and some minerals are also accompanied. At present, some scholars have determined the heavy metals and harmful elements Cu, Cr, Cd, Pb, As, Ni and trace metal elements Co, Sr, Zn in dragon bone. The determination is based on the risk of exceeding the standard of heavy metals in dragon bone and some trace elements beneficial to the human body, but the overall range is narrow and lacks pertinence. There is also a method of using X-ray diffraction to establish a fingerprint to identify the authenticity of dragon bone, which is based on the crystal structure characteristics of the main components of hydroxyapatite and calcite (CaCO3) and a small amount of quartz in dragon bone to make judgments, but it is not suitable for joint dragon bone and has a narrow application range. Near-infrared spectroscopy is used to identify dragon bone and modern animal bone pseudo-products. The organic components in dragon bone have disappeared in the process of geological movement or weathering, and the model is constructed by the vibration of crystal water and hydroxyl (-OH) in inorganic substances, which has the problems of lack of specificity and large interference.

[0004] In the published patent CN120121655A, it is proposed to use a scanning electron microscope equipped with an EDS energy spectrometer to analyze the element composition of the sample surface, combine with an isotope mass spectrometer to determine the stable isotope ratio of δ13C, δ2H, δ18O and δ15N in the sample, extract the first three principal components based on sparse partial least squares discriminant analysis, and construct a three-dimensional discriminant space containing the distribution characteristics of calcium and phosphorus elements and isotopic fingerprint to identify dragon bone. The method has good repeatability and reliable discrimination results, but the detection element range is limited, it cannot realize the simultaneous detection of multiple elements, the detection limit is high, and it is not suitable for the analysis of trace elements.

[0005] It should be noted that the above content belongs to the technical cognition of the inventor. Due to the vast and complex technical content in the field, the above content of the present application does not necessarily constitute the prior art. SUMMARY

[0006] 1. Technical problems to be solved by the invention: The present application proposes to scan all mass numbers from m / z 7 to 238 of the coral by inductively coupled plasma mass spectrometry (ICP-MS) from the element perspective, to screen out elements with large content differences in 15 different types of corals (different color genuine products, modern skeleton counterfeits, and non-medicinal product counterfeit), to further quantify, and to establish element fingerprint of corals in a targeted manner; to screen out key elements for distinguishing different color corals and genuine and fake corals by combining with chemometrics analysis; to perform semi-quantitative analysis of elements on "coral spots", brown mottling, and white background on the same piece of genuine coral by using the non-destructive feature of energy dispersive X-ray fluorescence (EDXRF), and to perform supplementary analysis on elements (such as Si, P, etc.) that are not suitable for determination or have large interference in ICP-MS by using the advantages of rapid, efficient, and simultaneous determination of multiple elements. A method for constructing element fingerprint of corals and distinguishing genuine and fake corals based on ICP-MS / EDXRF is provided to solve the technical problems existing in the background art.

[0007] 2. Technical solutions: To achieve the above-mentioned purpose, the technical solutions provided by the present application are as follows: a method for constructing element fingerprint of corals and distinguishing genuine and fake corals based on ICP-MS / EDXRF, comprising the following steps: Step S1: Take coral samples including different color genuine corals and various types of counterfeit products, perform ICP-MS analysis, scan all mass numbers from m / z 7 to 238 of the corals, screen out elements with large content differences in 15 different types of corals and perform quantification, and respectively establish different color genuine coral control fingerprint and counterfeit product control fingerprint. The control fingerprint is a broken line box plot. Then, semi-quantitative analysis of elements in different parts of the coral is performed by EDXRF detection for distinguishing genuine and fake corals and judging different counterfeit product types; Step S2: Take the coral powder to be detected for ICP-MS analysis, compare the color of the coral powder with the corresponding genuine coral control fingerprint, and simultaneously perform EDXRF determination on the coral to be detected. The block sample is checked for "coral spots" and the contents of Mn, U, and I in the "coral spots" and other parts are detected. The powder sample is detected for Sr, U, and I contents, and the results are combined for genuine and fake identification.

[0008] Further, the ICP-MS analyzer used in the ICP-MS analysis is an Agilent ICP-MS 7900 type.

[0009] Further, the EDXRF detector used in the EDXRF detection is a Shimadzu EDX7200 type.

[0010] Further, the ICP-MS sample pretreatment step is as follows: taking the bone sample powder, passing through a No. 5 sieve, taking 0.2 g, accurately weighing, placing in a microwave digestion tank, adding nitric acid 5 mL, mixing, adding an inner cover and standing overnight, tightening the tank cover, microwave digestion, digestion program: 5 min to 90℃, keeping for 20 min, 5 min to 120℃, keeping for 10 min, 5 min to 185℃, keeping for 40 min; cooling, taking out, transferring the digestion solution and washing with water, adding hydrochloric acid 2 mL, diluting to 50 mL with water, shaking well, obtaining the test sample solution, further diluting 10 or 50 times for elements such as Fe, Mn and U out of the standard curve range; if the digestion solution is turbid, centrifuging, pouring out the supernatant, transferring the residue to the original digestion tank with 4 mL of hydrofluoric acid, heating on an electric hot plate at 150℃ until complete digestion, and then acid-chasing to near dryness, diluting to 50 mL with water, shaking well, and calculating the element content based on the total amount of the supernatant and the residue.

[0011] Further, the EDX sample pretreatment step is as follows: the bone sample is divided into blocks and powder, the block-shaped bone is directly measured, and the powder sample is loaded into a sample cup and sealed for testing with a Mylar film.

[0012] Further, the ICP-MS conditions are as follows: He reaction mode, He flow rate 0.42 mL·min -1 ; acquisition mode skip peak, peak type 3 points, integration time 0.3 s, repeated acquisition number 3, scan number 100; sample lifting speed 0.3 r·s -1 , lifting time 20 s, stabilization time 20 s; sampling depth 10 mm, plasma flow rate 15 L·min -1 , carrier gas flow rate 1.07 L·min -1 ; radio frequency power 1550 W.

[0013] Further, the EDX conditions are as follows: atmosphere, collimator 3 mm, filter 1#, 2# and 4#, target material Rh, and the instrument parameters are as follows:

[0014] Further, the condition for determining the true product in the step S2 is that the contents of the 15 elements are basically within the box range, the broken line trend of each element is basically consistent with the control fingerprint spectrum under the color category, and the content of U is > 50 mg·kg -1EDXRF analysis was performed on block samples of keel. The results should show that the Mn content in the "keel spot" location is significantly higher than that in other parts, the U and I contents detected in different parts are relatively similar, and Sr, U, and I are detected in powder samples.

[0015] Furthermore, the criteria for determining whether a product is a modern animal bone counterfeit in step S2 are: the content of 15 elements is significantly lower than that of genuine products, and the content of other elements, except for Fe and Mn, is basically <5 mg·kg. -1 EDXRF analysis showed no "keel spot" and almost no detection of U and I. The Sr content was very low, close to the detection limit.

[0016] Furthermore, the criteria for identifying other paleontological fossils as forgeries in step S2 are: the content and trend of 15 elements are similar to those of genuine fossils, and the content of U is >50 mg·kg⁻¹. -1 EDXRF analysis showed no "dragon bone spots" and detected U, but the I content was close to the detection limit.

[0017] 3. Beneficial effects: The method for constructing and identifying genuine and counterfeit dragon bones based on ICP-MS / EDXRF combined, provided by this invention, can effectively distinguish between dragon bones of different colors, modern skeletal counterfeits, and counterfeit non-pharmaceutical varieties. It enables simultaneous detection of multiple elements, allowing ICP-MS to reflect the differences in trace, micro, and macro elements in different dragon bones, while also using non-destructive and rapid EDXRF detection to quickly assist in identifying genuine and counterfeit dragon bones. Furthermore, it allows for the analysis of elements at different locations within the same dragon bone, providing a theoretical basis for the clinical "differentiation of appearance and quality" of dragon bones. This method overcomes the problem that existing technologies cannot comprehensively and objectively reflect the elemental content of dragon bones.

[0018] It should be noted that the structures not described in this invention are not related to the design points and improvement directions of this invention, and are the same as or can be implemented using existing technologies, so they will not be elaborated here. Attached Figure Description

[0019] Figure 1 The fingerprint spectrum of different color elements of the genuine keel of this invention; Figure 2 This invention presents the elemental fingerprint spectrum of counterfeit dragon bones and a comparison chart of the elemental content of different types of counterfeit dragon bones. Figure 3 The following are the clustering results and fragmentation diagrams of the keel samples in this invention; Figure 4 This is an image of different parts of the keel, EDXRF detection number W-6, as presented in this invention. Figure 5 The present invention provides EDXRF detection spectra of different colored keel and counterfeit products. Detailed Implementation

[0020] To facilitate understanding of the present invention, a more complete description of the invention will be given below with reference to the accompanying drawings, which illustrate several embodiments of the invention. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of the invention will be more thorough and complete.

[0021] Example 1: Screening for genuine and counterfeit keel bones based on elemental fingerprinting ICP-MS conditions: He reaction mode, He flow rate 0.42 mL / min -1 The acquisition method was spectrum sampling, with three peak points, an integration time of 0.3 s, three repeated acquisitions, and 100 scans; the sample rise rate was 0.3 r / s. -1 The rise time was 20 seconds, the stabilization time was 20 seconds, the sampling depth was 10 mm, and the plasma flow rate was 15 L·min. -1 Carrier gas flow rate 1.07 L·min -1 RF power 1550W.

[0022] Preparation of Standard Solutions and Internal Standard Solutions: Accurately measure appropriate amounts of mixed standard solutions of As, Cr, Cu, Fe, Mn, Ni, Pb, Se, U, and V, and single-element standard solutions of Sc, La, Y, and Ge. Dilute with 5% nitric acid solution to prepare solutions containing 0, 1, 5, 20, 50, and 100 ng·mL for each element. -1 A mixed standard solution was prepared. Simultaneously, the Hg single-element standard solution was diluted with a 5% nitric acid + 4% hydrochloric acid mixed solution to prepare mass concentrations of 0, 0.5, 1, 2, 3, and 4 ng·mL. -1 A series of standard solutions (prepare fresh before use). Separately, accurately measure appropriate amounts of In, Bi, and Rh single-element standard solutions and dilute them with 5% nitric acid solution to a concentration of 100 ng / mL for each element. -1 A mixed internal standard solution.

[0023] Preparation of the test solution: Accurately weigh 0.2 g of dragon bone sample powder (passed through a No. 5 sieve), place it in a microwave digestion vessel, add 5 mL of nitric acid, mix well, cover with the inner lid and let stand overnight. Tighten the lid and microwave digest (digestion program: 5 min to 90℃, hold for 20 min; 5 min to 120℃, hold for 10 min; 5 min to 185℃, hold for 40 min). Cool, remove, transfer the digestion solution and wash with water, add 2 mL of hydrochloric acid, dilute with water to 50 mL, shake well, and the test solution is obtained (elements outside the standard curve range, such as Fe, Mn, and U, should be further diluted 10 or 50 times before determination). If the digestion solution is turbid, centrifuge, pour off the supernatant, and transfer the residue to the original digestion vessel in portions with 4 mL of hydrofluoric acid. Heat on a hot plate at 150℃ until complete digestion, and remove the acid to near dryness. Dilute with water to 50 mL, shake well, and calculate the element content by the sum of the total amount of the supernatant and the residue. Prepare a blank solution using the same method.

[0024] Sample determination: The mixed internal standard solution and the mixed standard solution were simultaneously injected into the sample via two separate peristaltic pumps for analysis. The measured values ​​(average of three readings) were plotted on the ordinate and the concentration on the abscissa to create a standard working curve. The test sample was analyzed using the same method, and the concentrations (ng·mL) of each element in the test sample solution were read from the standard curve. -1 Because keel bones are rich in Fe and Mn, and differ significantly from other elements, the contents of these two elements were corrected to facilitate the establishment of fingerprint spectra. Specifically, the Fe content was reduced by a factor of 50, and the Mn content by a factor of 10. Each element was used as the x-axis, and the corrected content (mg·kg⁻¹) was plotted. -1 Using the y-axis as the vertical axis, draw box plots separately for genuine and counterfeit items, as shown below. Figure 1 The fingerprint patterns of different color elements shown are from genuine keel pieces. Figure 2 The image shows the elemental fingerprint spectrum of counterfeit keel bones and a comparison chart of the elemental content of different types of counterfeit keel bones.

[0025] Example 2: Identification of Genuine and Counterfeit Keel Based on EDXRF EDX conditions: atmospheric atmosphere, collimator 3mm, filters 1#, 2#, 4#, target material Rh, instrument parameters are detailed in Table 1.

[0026]

[0027] Sample preparation: Keel samples are divided into block and powder. Block keel samples are measured directly, while powder samples are placed in a sample cup and sealed with a Mylar membrane for testing.

[0028] Sample analysis: Check for the presence of "keel spots" in block samples, compare the Mn content at the "keel spot" location with other parts, and detect the U and I content in different parts. For powder samples, the main content to be detected is Sr, U, and I. Based on ICP-MS results, in genuine keel-patterned block samples, EDXRF analysis should show a significantly higher Mn content at the "keel spot" location than in other parts, with relatively similar U and I contents detected in different parts (refer to...). Figure 4 As shown), Sr, U, and I were detected in the powder sample (refer to...). Figure 5 (As shown). Modern animal skeletal artifacts showed no "keel spots" on EDXRF testing, and U and I were almost undetectable, with Sr content very low, close to the detection limit. Other paleontological fossil artifacts showed no "keel spots" on EDXRF testing, and U was detected, but I content was close to the detection limit.

[0029] Example 3: Construction process of elemental fingerprint spectrum 1. Instruments and Materials instrument Agilent 1260HPLC and ICP-MS 7900 coupled system (Agilent Technologies, USA); EDX 7200 energy-dispersive X-ray fluorescence spectrometer (Shimadzu Corporation, Japan); CEMMARS 6 CLASSIC microwave digester (Peranton Corporation, USA); XS105DU 0.0001 g electronic balance (Mettler-Toledo, Switzerland); Thermo Scientific Heraeus Multifuge X3 centrifuge (Thermo Fisher Scientific, USA); Millipore Synergy ultrapure water system (Millipore Corporation, USA).

[0030] Material A mixed standard solution of As, Cr, Cu, Fe, Mn, Ni, Pb, Se, U, V, etc. (Agilent Technologies, lot number 51-116CRY2, mass concentration 10 μg·mL) -1 ); Sc, La, and Y single-element standard solutions (National Institute of Metrology, China, batch numbers 2301, 23081, and 24081, respectively, with a mass concentration of 1000 μg·mL). -1 ); Ge, Hg, In, Bi, Rh single-element standard solutions (National Center for Analysis and Testing of Nonferrous Metals and Electronic Materials, batch numbers 23C039-1, 241046-2, 243064, 241034-2, and 241021 respectively, with a mass concentration of 1000 μg·mL for each). -1 A mixed standard tuning solution of Ce, Co, Y, Li, and Tl (Agilent Technologies, lot number 8-224MFY2, mass concentration 10 μg·mL). -1Nitric acid was UP grade, hydrofluoric acid and hydrochloric acid were of superior purity, and ultrapure water was prepared by a Millipore Synergy ultrapure water system.

[0031] Thirty batches of keel samples were collected and numbered according to the color of the powder. Among them, F1 to F5 were counterfeit products, and FT6 to FT7 were adulterated products. Detailed information is shown in Table 2.

[0032]

[0033] 2. Methods and Results Selection of fingerprint pattern elements In preliminary research, semi-quantitative ICP-MS was used to screen 88 batches of samples for all mass numbers ranging from m / z 7 to 238. This initially revealed an intrinsic relationship between the color and elements in the keel bones, and found significant differences in the content of elements such as U, Pb, La, Y, Ge, As, Se, Ni, Cu, V, Cr, Mn, Fe, and Sc between genuine and counterfeit keel bones. Some batches showed higher levels of As, Pb, U, and Hg. The screened elements were further quantified using ICP-MS, followed by cluster analysis (HCA) and principal component analysis (PCA) to establish a targeted elemental fingerprint spectrum for the keel bones.

[0034] Choice of digestion method To reduce interference from polyatomic ions, nitric acid was initially used for digestion. However, some samples were not completely digested, possibly due to the presence of quartz and small amounts of clay minerals in some of the keel bones. Referring to the acid digestion system for element determination in soil, microwave digestion was performed on the difficult-to-digest keel bones using 5 mL nitric acid + 1 mL hydrochloric acid + 4 mL hydrofluoric acid. However, after removing the acid and bringing the volume to a constant, a white gelatinous substance was produced. This may be because the keel bones contain a large amount of Ca, which formed calcium fluoride precipitate. Additionally, rare earth elements can also produce fluoride precipitates, leading to inaccurate quantification. To reduce Ca interference, nitric acid digestion was followed by centrifugation. The incompletely digested residue was further digested with hydrofluoric acid until clear and transparent. Measurements showed that the residue still contained a high proportion of As, Fe, U, Pb, and other elements. For the difficult-to-digest samples, the data from both digestion steps were added together to obtain the content values ​​for 15 elements.

[0035] Establishment of elemental fingerprinting Because keel bones are rich in Fe and Mn, and differ significantly from other elements, the contents of these two elements were corrected to facilitate the establishment of fingerprint spectra. Specifically, the Fe content was reduced by a factor of 50, and the Mn content by a factor of 10. Each element was plotted on the x-axis, and the corrected content (mg·kg⁻¹) was plotted on the y-axis. -1Using the ordinate as the vertical axis, box plots were drawn separately for genuine and counterfeit items. Among the counterfeit items, F-2 to F-4 are modern bovine or pig bones used as substitutes, with elemental contents relatively close to those of genuine fossils. Except for Fe, Ni, Cu, and Hg, other elements are generally much lower than those in genuine fossils. FT-6 to FT-7 are adulterated, with FT-7 being even closer to the genuine item. FT-6 shows significantly lower levels of U, Se, and rare earth elements Sc, Y, and La, possibly indicating a higher proportion of adulteration. F-1 and F-5 are non-medicinal animal fossils used as substitutes, and are very close to the genuine item. For detailed fingerprint spectra of genuine and counterfeit items, please refer to [link to fingerprint analysis]. Figures 1-2 Judging from the variety of colors of genuine products, the brown keel (B-1 to B-7) has a higher content of almost all elements except Hg than other colors.

[0036] Chemometrics Analysis The test results of 30 batches of keel samples were imported into SPSS 19 software, and HCA analysis was performed using the Ward method and squared Euclidean distance. Clustering results and scree plots are detailed below. Figure 3 Brown keel (B-7) was grouped into a separate category 1; other batches, along with C-1 and C-3, were grouped into category 2; and white, cyan, and counterfeit batches were grouped into category 3. KMO and Bartlett tests were performed. The KMO value was 0.746, and Sig. was 0, indicating suitability for PCA analysis. Eigenvalues ​​>1 were extracted, resulting in four principal components. Principal component 1 (Eigenvalue 8.901, cumulative variance contribution 59.34%) contained information on Sc, V, Fe, Ni, Cu, Ge, As, Se, Y, La, and Pb; principal component 2 (Eigenvalue 2.133, cumulative variance contribution 73.56%) contained information on Cr and U; principal component 3 (Eigenvalue 1.497, cumulative variance contribution 83.54%) contained information on Mn; and principal component 4 (Eigenvalue 1.086, cumulative variance contribution 90.78%) contained information on Hg. These four principal components essentially reflect the overall information of the 15 elements in the keel. It is generally assumed that an absolute value of the loading value > 0.800 indicates a correlation between the principal component and the associated element. Principal component 1 shows a high positive correlation with Sc, V, Fe, Cu, Ge, As, Se, Y, and Pb, while principal component 2 shows a high positive correlation with Cr and U. These elements are characteristic elements of keel and key factors in distinguishing different colored keels from genuine and counterfeit keels. See Table 3 for the keel principal component factor loading matrix.

[0037]

[0038] Methodological Validation Linearity investigation: using the mass concentration of each element (ng·mL) -1A standard curve was plotted with the count ratio (CPS value) on the x-axis and the count ratio on the y-axis. The linear relationships among the elements were good, with correlation coefficients all exceeding 0.999. The limits of quantitation (LOQ) were calculated by collecting blank solutions of the samples 11 times consecutively and using 10 times the standard deviation of the CPS values. The content of all elements in the 30 batches of dragon bones was greater than the LQ.

[0039] Precision: For a mass concentration of 50 ng / mL -1 Mixed standard solution and 1 ng / mL -1 The Hg standard solution was injected six times consecutively, and the RSD of each element's mass concentration was 1.2% to 4.0%, indicating that the instrument has good precision.

[0040] Repeatability: Take sample powder numbered B-1 and prepare 6 parallel test solutions. The RSD of the mass concentration of each element is calculated to be 2.1% to 5.2%, indicating that the method has good repeatability.

[0041] Spiking recovery test: Take 0.1g of sample powder No. B-1, accurately add appropriate amounts of mixed standard solution and Hg single element standard solution, prepare and determine the test solution according to the test sample solution. The results show that the spiked recovery rate of each element is 78.8% to 119.5%.

[0042] Sample Measurement Thirty batches of dragon bone samples were tested, and the solutions were prepared according to the law. The results of the content of 15 elements are shown in Table 4. Among the counterfeit samples, F-2 to F-4 were modern bovine or pig bones used as substitutes. Their elemental content was relatively close to that of genuine dragon bone, except for Fe, Ni, Cu, and Hg, the content of other elements was significantly lower than that of genuine dragon bone. FT-6 to FT-7 were adulterated. FT-7 was even closer to genuine dragon bone. FT-6 showed significantly lower levels of U, Se, and rare earth elements Sc, Y, and La, possibly indicating a higher proportion of adulterant. F-1 and F-5 were non-medicinal animal fossils used as substitutes, and were very close to genuine dragon bone. For detailed fingerprint spectra of genuine and counterfeit samples, see [link to table]. Figures 1-2 Judging from the variety of colors of genuine products, the brown keel (B-1 to B-7) has a higher content of almost all elements except Hg than other colors.

[0043]

[0044] In summary, the method for constructing and identifying genuine and counterfeit keel based on ICP-MS / EDXRF combined with the present invention can be effectively used to control the quality of keel. Compared with traditional empirical identification methods, it is more comprehensive and objective. With its advantages of speed, efficiency and simultaneous determination of multiple elements, it reveals the quality differences of different colors of keel and the elemental composition of counterfeit products.

[0045] The above-described embodiments are merely illustrative of certain implementations of the present invention, and are described in a relatively specific and detailed manner. However, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements are all within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A method for constructing and verifying the authenticity of keel elemental fingerprint spectra based on ICP-MS / EDXRF, characterized in that, Includes the following steps: Step S1: Take keel samples, including genuine keel of different colors and various types of counterfeit products, and perform ICP-MS analysis. Scan all mass numbers of the keel with m / z from 7 to 238 to screen out the elements with large differences in content in 15 different types of keel and quantify them. Establish fingerprint spectra for genuine keel of different colors and for counterfeit products. The fingerprint spectra are broken-line box plots. Then, use EDXRF detection to perform semi-quantitative analysis of elements in different parts of the keel for identifying the authenticity of the keel and judging different types of counterfeit products. Step S2: Take the keel powder to be tested and perform ICP-MS analysis. Compare the color of the keel powder with the corresponding fingerprint spectrum of the genuine keel. At the same time, perform EDXRF determination on the keel to be tested. During the determination, check whether there are "keel spots" on the block sample and detect the Mn, U, and I content of the "keel spots" and other parts. Detect the Sr, U, and I content of the powder sample. Combine the results of both to identify the authenticity.

2. The method for constructing and verifying the authenticity of keel elemental fingerprints based on ICP-MS / EDXRF as described in claim 1, characterized in that: The inductively coupled plasma mass spectrometer used for the ICP-MS analysis was an Agilent ICP-MS7900.

3. The method for constructing and verifying the authenticity of keel elemental fingerprints based on ICP-MS / EDXRF as described in claim 1, characterized in that: The energy-dispersive X-ray fluorescence spectrometer used for the EDXRF detection was a Shimadzu EDX7200 model.

4. The method for constructing and verifying the authenticity of keel elemental fingerprints based on ICP-MS / EDXRF as described in claim 1, characterized in that: The ICP-MS sample pretreatment steps are as follows: Take keel bone sample powder, pass it through a No. 5 sieve, weigh 0.2 g precisely, place it in a microwave digestion vessel, add 5 mL of nitric acid, mix well, cover with the inner lid and let stand overnight, tighten the lid, and microwave digest. The digestion program is: 5 min to 90℃, hold for 20 min, 5 min to 120℃, hold for 10 min, 5 min to 185℃, hold for 40 min; cool, remove, transfer the digestion solution and wash with water. Dilute with 2 mL of hydrochloric acid, dilute with water to 50 mL, and shake well to obtain the test solution. For elements exceeding the standard curve range, such as Fe, Mn, and U, further dilute by 10 or 50 times before determination. If the digestion solution is turbid, centrifuge, pour off the supernatant, and transfer the residue to the original digestion vessel in portions with 4 mL of hydrofluoric acid. Heat on a hot plate at 150°C until complete digestion, and remove the acid until nearly dry. Dilute with water to 50 mL, shake well, and calculate the element content as the sum of the total amount of the supernatant and the residue.

5. The method for constructing and verifying the authenticity of keel elemental fingerprints based on ICP-MS / EDXRF as described in claim 1, characterized in that: The EDX sample pretreatment steps are as follows: the keel samples are divided into block and powder. The block keel samples are directly measured, and the powder samples are put into sample cups and sealed with Mylar membrane for testing.

6. The method for constructing and verifying the authenticity of keel elemental fingerprint spectrum based on ICP-MS / EDXRF as described in claim 1, characterized in that: The ICP-MS conditions were: He reaction mode, He flow rate 0.42 mL / min. -1 The acquisition method involved peak skipping, with three peak points sampled. The integration time was 0.3 s, and the acquisition was repeated three times, with a total of 100 scans. The sample lift rate was 0.3 r / s. -1 The boost time is 20 seconds, and the stabilization time is 20 seconds. Sampling depth 10 mm, plasma flow rate 15 L·min -1 Carrier gas flow rate 1.07 L·min -1 RF power 1550W.

7. The method for constructing and verifying the authenticity of keel elemental fingerprint spectrum based on ICP-MS / EDXRF as described in claim 1, characterized in that: The EDX conditions are: atmospheric atmosphere, 3mm collimator, filters #1, #2, and #4, and target material Rh; wherein: For the Na-Sc element group, the tube voltage was 15kV, the tube current was 1000-Auto, no filter was used, the acquisition energy was 0-20keV, the analysis energy was 0.00-4.40keV, and the acquisition time was 30s. For Zn-As and Pb element groups, the tube voltage is 50kV, the tube current is 1000-Auto, the filter is #4, the acquisition energy is 0-40keV, the analysis energy is 8.50-14.50keV, and the acquisition time is 100s. For the Al-U element group, the tube voltage was 50kV, the tube current was 984-Auto, no filter was used, the energy collected was 0-40keV, the energy analyzed was 0.00-40.00keV, and the acquisition time was 30s. For the Rh-Cd element group, the tube voltage was 50kV, the tube current was 1000-Auto, the filter was #1, the acquisition energy was 0-40keV, the analysis energy was 19.20-23.50keV, and the acquisition time was 100s. For the Sc-K element group, the tube voltage was 15kV, the tube current was 1000-Auto, the filter was #2, the energy collected was 0-20keV, the energy analyzed was 2.10-3.40keV, and the acquisition time was 30s.

8. The method for constructing and verifying the authenticity of keel elemental fingerprints based on ICP-MS / EDXRF as described in claim 1, characterized in that: The conditions for determining authenticity in step S2 are as follows: the content of 15 elements is basically within the box curve range, the trend of each element's line is basically consistent with the fingerprint spectrum of the corresponding color category, and the quantitative result shows that the content of U is >50 mg·kg. -1 EDXRF analysis was performed on block samples of keel. The results should show that the Mn content in the "keel spot" location is significantly higher than that in other parts, the U and I contents detected in different parts are relatively similar, and Sr, U, and I are detected in powder samples.

9. The method for constructing and verifying the authenticity of keel elemental fingerprint spectrum based on ICP-MS / EDXRF as described in claim 1, characterized in that: The criteria for identifying modern animal bone as a counterfeit in step S2 are: the content of 15 elements is significantly lower than that of genuine products, and the content of other elements except Fe and Mn is basically <5 mg·kg. -1 EDXRF analysis showed no "keel spot" and almost no detection of U and I. The Sr content was very low, close to the detection limit.

10. The method for constructing and verifying the authenticity of keel elemental fingerprints based on ICP-MS / EDXRF as described in claim 1, characterized in that: The criteria for identifying other paleontological fossils as forgeries in step S2 are: the content and trend of 15 elements are similar to those of genuine fossils, and the content of U is >50 mg·kg⁻¹. -1 EDXRF analysis showed no "dragon bone spots" and detected U, but the I content was close to the detection limit.

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