Eu-based rare earth complex, preparation method and application

Abstract

The invention belongs to the technical field of application of metal organic framework materials, and particularly relates to an Eu-based rare earth complex, a preparation method and application, and the Eu-based rare earth complex can be used for detecting pollutants such as TCY and ATP in water. The novel rare earth metal organic framework compound material synthesized by the invention has remarkable luminescence property, and not only can identify ATP in numerous biomolecules, but also can identify TCY molecules in multiple antibiotic molecules. The material has excellent fluorescence recognition performance on two molecules and has good standard addition recovery rate in an actual sample, on the basis, an intelligent sensing platform based on a mobile phone is constructed, rapid sensing detection on TCY and ATP molecules can be achieved, and based on the remarkable red luminescence performance of a rare earth metal organic framework compound under an ultraviolet lamp, the material can be used for detecting the TCY and ATP molecules. The manufactured portable seal box can be used for fingerprint anti-counterfeiting.

Description

Technical Field

[0001] The present invention belongs to the technical field of the application of metal-organic framework materials, and particularly relates to a Eu-based rare earth complex, a preparation method and an application thereof. Background Art

[0002] Social development and human activities all over the world have led to a serious public health problem - water pollution. Since the remaining drugs are considered to cause ecological problems and have long-term cumulative harmful effects on humans and ecosystems, they are classified as a type of water pollution. Due to abuse and improper disposal, it has been found that the broad-spectrum antibiotic tetracycline (TCY) is widely present in natural waterways. Residual TCY from the environment can enter the body in various ways, thus endangering human health. Monitoring the TCY level in the ecosystem or food is of great significance in protecting human health.

[0003] Adenosine triphosphate (ATP) is a multifunctional nucleotide that contains three negatively charged phosphate groups. It plays a variety of important roles in cell biology, mainly as a universal energy currency and signal molecule in living cells to coordinate the response to the energy state, and partly by regulating ion channels and activating signal cascades. In addition to its role in energy metabolism and signal transduction, ATP is also incorporated into nucleic acids by polymerase during DNA replication and transcription. It has been found that the concentration and dissipation rate of ATP are closely related to many diseases, such as hypoxia, hypoglycemia, ischemia, Parkinson's disease and certain malignant tumors. Therefore, realizing the detection of ATP not only has scientific research significance, but also has clinical importance.

[0004] Metal-organic framework materials are organic-inorganic hybrid crystal materials with rich active sites and adjustable structures, and have the advantages of structural diversity, performance variability and mild and operable synthesis conditions. In addition, due to the controllability and adjustability of organic ligands, metal-organic framework materials show advantages different from traditional optical materials in fluorescence sensing and show good application prospects in the detection of antibacterial drugs and biomolecules.

[0005] With the increase in pollutants, more and more detection methods and probes have been developed. Fluorescence sensing is widely used in the detection of environmental pollutants due to its advantages such as simple operation and high sensitivity.

[0006] In the prior art, patent application CN117866224A discloses a Eu-MOF ratiometric fluorescence probe material, its preparation method, and its application in detecting tetracycline. Under the excitation of ultraviolet light at 365 nm, the ratiometric fluorescence probe of this invention exhibits red light emission dominated by a wavelength of 614 nm. After adding tetracycline (TCs), it exhibits blue light emission dominated by 480 nm, achieving ratiometric fluorescence detection with a relatively low detection limit. This fluorescence probe can highly selectively identify tetracycline in aqueous solution and has the advantages of strong stability, reusability, and simple operation.

[0007] In the prior art, patent application CN114672302A relates to the preparation and application of a near-infrared MOF fluorescence probe based on silicon rhodamine for detecting adenosine triphosphate (ATP). The structure of this fluorescence probe consists of a nanoscale metal-organic framework (ZIF-90) and a near-infrared fluorophore based on silicon rhodamine encapsulated therein. This fluorescence probe is a near-infrared MOF fluorescence probe for ATP based on silicon rhodamine and can be used to detect the content of ATP in living cells.

[0008] The above patent technologies can only be used for the detection of one of TCY and ATP, and none of them have achieved intelligent sensing applications for mobile phones and lack practical applications in anti-counterfeiting. However, with the increase in pollutants, there are few fluorescence probes that can simultaneously detect antibacterial drugs and biomolecules. Therefore, the present invention proposes a Eu-based rare earth complex, its preparation method, and its applications in fluorescence recognition, mobile phone intelligent sensing, and anti-counterfeiting. Summary of the Invention

[0009] The purpose of the present invention is to provide a Eu-based rare earth complex, its preparation method, and its applications. The synthesized novel rare earth metal-organic framework compound material has remarkable luminescent properties. It can not only identify ATP among numerous biomolecules but also identify TCY molecules among various antibiotic molecules. This material has excellent fluorescence recognition performance for the two molecules, has a good spike recovery rate in actual samples, and on this basis, constructs an intelligent sensing platform based on a mobile phone, which can achieve rapid sensing detection of ATP and TCY molecules. Based on the significant red luminescent properties of the rare earth metal-organic framework compound under ultraviolet light, a portable seal box can be made for fingerprint anti-counterfeiting.

[0010] The technical solutions adopted by the present invention are specifically as follows:

[0011] A Eu-based rare earth complex, the chemical formula of the Eu-based rare earth complex is [Eu2(L)3(H2O)] n , where H3L is 4-(2,4,6-tricarboxyphenyl)-3,2’:6,3”-terpyridine; the single crystal structure of this compound belongs to the orthorhombic system, the space group is C2221, and the unit cell parameters are: bond lengths Bond length Bond length Bond angles α = 90°, β = 90°, γ = 90°.

[0012] Preferably, the Eu-based rare earth complex has the molecular formula C 72 H 41 Eu2N9O 19 ; The molecular weight of the compound is 1640.06.

[0013] Preferably, for the single crystal structure, the unit cell volume The number of molecules in the unit cell Z = 4, the crystal density ρ calcd = 1.625 g / cm 3 , the linear absorption coefficient μ = 13.951 mm –1 , the number of electrons in the unit cell F(000) = 3256, the diffraction angle range of the unit cell θRange = 3.5 - 68.3 deg, the number of diffraction points collected = 34170, the independent diffraction points (R int ) = 0.064, the number of diffraction points with intensity greater than 2σ = 5532.

[0014] A preparation method of a Eu-based rare earth complex, mixing H3L, Eu(NO3)3·6H2O and water and stirring for 15 - 45 minutes, then transferring and sealing in a reactor, heating to 160 - 180 °C, with a heating rate of 7 - 13 °C / h, holding for 68 - 80 hours, cooling to room temperature, with a cooling rate of 3 - 8 °C / h; thus obtained; wherein, the molar ratio of H3L to Eu(NO3)3·6H2O is 1:1.5, and the dosage ratio of H3L to water is 0.1 mmol: 9 - 15 mL.

[0015] An application of a Eu-based rare earth complex in detecting food contaminants, the food contaminants include: antibacterial drugs and biomolecules, and the antibacterial drugs and biomolecules include TCY and ATP.

[0016] An application of a Eu-based rare earth complex in the intelligent sensing of mobile phones.

[0017] An application of a Eu-based rare earth complex in fingerprint anti-counterfeiting.

[0018] The technical effects achieved by the present invention are:

[0019] The present invention synthesizes a new Eu-based rare earth complex, which can be used for the detection of food pollutants such as TCY and ATP in water and food. The novel metal-organic framework compound material synthesized in the present invention has excellent luminescent properties. It can not only identify TCY among numerous antibiotics, but also identify the biomolecule ATP in water. It also constructs a mobile phone intelligent sensing platform to achieve rapid detection of TCY and ATP, and prepares a portable seal box for anti-counterfeiting applications. The material has a low detection limit for different molecules, demonstrating the advantages of easy preparation, low cost, simple operation, high sensitivity, and high selectivity. Description of the Drawings

[0020] Figure 1 It is the chemical structural formula of the ligand of the Eu-based rare earth complex (Sample 1) of the present invention;

[0021] Figure 2 It is the infrared (A) and thermogravimetric analysis (B) of Sample 1 of the present invention;

[0022] Figure 3 It is the X-ray diffraction pattern of the single crystal;

[0023] Figure 4 is the crystal structure of the single crystal. Among them, A is the coordination environment diagram of Sample 1, and B is the 3D network structure of Sample 1;

[0024] Figure 5 It is the ultraviolet absorption spectra of the main ligand, Sample 1, and different antibiotic molecules and biomolecules;

[0025] Figure 6 It is the excitation and emission spectra of Sample 1;

[0026] Figure 7 is the detection result diagram of Sample 1 against antibacterial drugs. Among them, A is the curve diagram, and B is the bar chart;

[0027] Figure 8 is the concentration titration of Sample 1 for identifying antibacterial drugs. Among them, A is the fitting diagram, and B is the curve diagram;

[0028] Figure 9 It is the anti-interference bar chart of Sample 1 for the detection of antibacterial drugs;

[0029] Figure 10 It is the fluorescence cycle data comparison diagram of Sample 1 for antibacterial drugs;

[0030] Figure 11 is the screening of biomolecules. Among them, A is the curve diagram, and B is the bar chart;

[0031] Figure 12 It is the concentration titration for identifying biomolecules. Among them, A is the fitting diagram, and B is the curve diagram;

[0032] Figure 13 It is the anti-interference bar chart for biomolecules;

[0033] Figure 14 It is a fluorescence cycle data comparison chart of biomolecules;

[0034] Figure 15 It is the comparison of XRD before and after titration;

[0035] Figure 16 It is a flowchart of mobile phone intelligent sensing;

[0036] Figure 17 It is the manufacturing process of an anti-counterfeiting seal box. Specific embodiments

[0037] In order to make the purpose and advantages of the present invention clearer, the present invention will be specifically described below in conjunction with embodiments. It should be understood that the following text is only used to describe one or several specific implementation manners of the present invention, and does not strictly limit the scope of protection of the specific requests of the present invention.

[0038] Example 1:

[0039] A Eu-based rare earth complex, the chemical formula of the Eu-based rare earth complex is [Eu2(L)3(H2O)] n , where H3L is 4-(2,4,6-tricarboxyphenyl)-3,2’:6,3”-terpyridine; the single crystal structure of this compound belongs to the orthorhombic system, the space group is C2221, and the unit cell parameters are: bond length Bond length Bond length Bond angle α = 90°, bond angle β = 90°, bond angle γ = 90°. The chemical structural formula is as Figure 1 shown.

[0040] Preferably, the molecular formula of the Eu-based rare earth complex is C 72 H 41 Eu2N9O 19 ; the molecular weight of the compound is 1640.06.

[0041] Preferably, for the single crystal structure, the unit cell volume The number of molecules in the unit cell Z = 4, the crystal density ρ calcd = 1.625 g / cm 3 , the linear absorption coefficient μ = 13.951 mm –1 , the number of electrons in the unit cell F(000) = 3256, the diffraction angle range of the unit cell θRange = 3.5 - 68.3 deg, the number of diffraction points collected = 34170, the independent diffraction points (R int ) = 0.064, the number of diffraction points with intensity greater than 2σ = 5532.

[0042] Example 2:

[0043] A preparation method of Eu-based rare earth complex, which comprises mixing H3L, Eu(NO3)3·6H2O and water and stirring for 15 - 45 minutes, then transferring and sealing in a reactor, heating to 160 - 180 °C at a heating rate of 7 - 13 °C / h, holding for 68 - 80 hours, and cooling to room temperature at a cooling rate of 3 - 8 °C / h; thus obtained; wherein, the molar ratio of H3L to Eu(NO3)3·6H2O is 1:1.5, and the dosage ratio of H3L to water is 0.1 mmol:9 - 15 mL.

[0044] In the actual synthesis process, for example: a mixture of H3L (0.1 mmol, 0.044 g), Eu(NO3)3·6H2O (0.15 mmol, 0.068 g) and 10 mL of H2O was stirred for 30 minutes, then transferred and sealed in a 25 mL reactor lined with Teflon, heated to 180 °C, held for 72 hours, and then cooled to room temperature at a rate of 5 °C / h. Calculated based on europium, colorless block crystals were obtained, denoted as sample 1, and the yield was 65%. H3L is 4-(2,4,6-tricarboxyphenyl)-3,2’:6,3”-terpyridine.

[0045] The characterization data of the Eu-based rare earth complex in the present invention: the elemental analysis results of sample 1 are shown in Table 1; the crystal data are shown in Table 2; the selected bond lengths and bond angles are shown in Table 3; the selected hydrogen bond distances and angles are shown in Table 4.

[0046] Table 1. Elemental analysis results

[0047]

[0048] Table 2. Crystal data

[0049]

[0050]

[0051] *R = ∑(F o –F c ) / ∑(F o ), **wR2 = {∑[w(F O(2) –F c 2 ) 2 / ∑(F O(2) ) 2} 1 / 2 .

[0052] Table 3: Selected bond lengths and bond angles

[0053]

[0054]

[0055]

[0056] Symmetry Codes: #1=2-x,y,1 / 2-z; #2=1 / 2+x,1 / 2+y,z; #3=3 / 2-x,3 / 2-y,-1 / 2+z; #4=1 / 2+x,3 / 2 -y,1-z; #5=3 / 2-x,1 / 2+y,1 / 2-z; #6=1-x,1-y,1 / 2+z; #7=x,1-y,1-z; #8=1-x,y,1 / 2-z.

[0057] Table 4: Selected hydrogen bond distances and bond angles

[0058]

[0059] Crystal structure analysis of Eu-based rare earth complexes in the present invention:

[0060] The analysis of the X-ray single crystal structure shows that sample 1 is composed of the orthorhombic system C2221 space group, presenting a three-dimensional stacked shale structure. Analysis of the coordination environment of the central ion shows that sample 1 has good symmetry and stability. According to the coordination environment diagram of sample 1, Figure 1 As shown, the asymmetric coordination environment unit contains two Eu 3+ , three oxygen-containing L 3- Ligand anion and 1 coordinated water molecule. Eu01 in sample 1 is combined with 5 L 3- The 10 oxygen atoms of the ligand (O3, O3', O4, O4', O5, O5', O6, O6', O9 and O9') form a 10-coordinated double-capped tetragonal anti-trigonal prism. 3- O3 and O9 of the ligand are located at the equatorial position, while O4, O5, and O6 are located at the axial position. 3- The 10 oxygen atoms of the ligand and water molecules (O1, O1', O2, O2', O7, O7', O10, O10', O11, O11') also form a 10-coordinated double-capped tetragonal anti-trigonal prism. In this double-capped tetragonal anti-trigonal prism, L 3- The O1, O10, and O11 of the ligand are in axial positions, and the remaining atoms are in equatorial positions.

[0061] Metal Eu 3+ With L 3- The oxygen-containing carboxylic acid coordinated anion adopts bidentate bridging coordination (coordination mode is μ3-η 2 :η 2 :η 2 ). The Eu-O bond length in the structure is inside. The bond angle of O-Eu-O is in the range of 47.2(6) - 166.8(3)°. In the structure of Sample 1, due to Eu 3+ center and L 3- The oxygen-containing ligand anions have two different coordinations. In its structure, L 3- forms a fence-like grid 1D chain structure by "holding hands" along the a-axis direction through Eu01, and continues to stack along the b-axis on the basis of Eu01 to form a 2D structure, and then forms a 3D structure by laminating along the c-axis through Eu02.

[0062] Figure 2 In A and B, they are respectively the infrared and thermogravimetric analyses of the single crystal, Figure 3 is the X-ray diffraction pattern of the single crystal powder, and Figure 4 is the crystal structure of the single crystal.

[0063] See Figure 2 In B, the sample has the first weight loss in the range of 85.9 - 182.9 °C, which is due to the free moisture in the sample. At 481.9 °C, the skeleton of the organic ligand molecules in the sample begins to collapse until the sample finally decomposes into oxides.

[0064] See Figure 3 , and the results show that in the range of 5 - 50 (2θ), the theoretical data graph and the experimental measured graph of the sample are consistent in both the peak shape of XRD and the 2θ position where the peaks are located, indicating that the sample is a pure phase. The main characteristic peaks are 5.50, 7.06, 7.96, 9.10, 11.04, 12.00, 12.76, 15.26, 16.32, 17.40, 20.28, 20.62, 24.20.

[0065] Example 3:

[0066] An application of a Eu-based rare earth complex in detecting food contaminants, wherein the food contaminants include: antibacterial drugs and biomolecules, and the antibacterial drugs and biomolecules include TCY and ATP.

[0067] In the antibacterial drug recognition experiment of the Eu-based rare earth complex in the present invention:

[0068] In the experiment of Sample 1 with antibacterial drugs chloramphenicol (CAP), sulfadiazine (SDZ), sulfamethoxazole (SMT), thiamphenicol (THI), sulfamethoxazole (SMZ), ibuprofen (IPF), amoxicillin (AMXL), imipenem nucleus (IMP), cefixime (CEF), indomethacin (IMC), tetracycline (TCY), it is found that it has sensing characteristics for the TCY antibacterial drug. For the sensing experiment, a powder of Sample 1 (5 mg) is suspended in 5 mL of water, and then the mixture is ultrasonically stirred for 30 minutes before testing to prepare Sample 1 (1 mg·mL -1) dispersion. The titration experiment was carried out by gradually adding an aqueous solution of the antibacterial drug to the aqueous dispersion of Sample 1. All experiments were repeated in four cycles. The quenching efficiency was calculated as [(I0 - I) / I0]×100%, where I0 and I are the fluorescence intensities before and after adding the analyte. These competitive experiments were carried out by adding 2.5 mL of an aqueous solution of TCY (1×10 -3 M) to 2.5 mL of an aqueous solution of other molecules (1×10 -3 M).

[0069] In the biomolecular recognition experiment of the Eu-based rare earth complex in the present invention:

[0070] In the experiment of Sample 1 with biomolecules, it was found to have sensing characteristics for ATP. The biomolecular experiments included: dopamine (DA), L-serine, L-cysteine (Cys), L-citrulline (Citn), L-tryptophan (Trp), phenylalanine (Phe), methionine (Met), glutamic acid (Glu), ascorbic acid (AA), lysine (Lys), urea (Urea), glucose (Gl), aspartic acid (Asp), histidine (His), ATP (adenosine triphosphate). For the sensing experiment, a dispersion of Sample 1 (1 mg·mL -1 ) was prepared by suspending the powder of Sample 1 (5 mg) in 5 mL of water and then ultrasonically stirring the mixture for 30 minutes before testing. The titration experiment was carried out by gradually adding an aqueous solution of biomolecules to the aqueous dispersion of Sample 1. All experiments were repeated in four cycles. The quenching efficiency was calculated as [(I0 - I) / I0]×100%, where I0 and I are the fluorescence intensities before and after adding the analyte. These competitive experiments were carried out by adding 2.5 mL of an aqueous solution of ATP (1×10 -2 M) to 2.5 mL of an aqueous solution of molecules (1×10 -2 M).

[0071] The above experimental results are shown in Table 5 below:

[0072] 1. Antibacterial drug experiment:

[0073] Crystal 1: Titration (using water as the solvent): 0.001 mol / L TCY, σ is 0.046062, K sv = 13308.07

[0074] The LOD is (3×0.046062) / 13308.07 = 1.04×10 -5 mol / L

[0075] 2. Biomolecular experiment:

[0076] Crystal 1: Titration with water as the solvent: 0.01 mol / L ATP, σ is 0.046062, K sv = 2479.16

[0077] The LOD is (3×0.046062) / 2479.16 = 5.57×10 -5 mol / L

[0078] Table 5. Recognition of antibacterial drugs, cations, and anions by Sample 1

[0079] Titration Ksv <![CDATA[R 2 > LOD / (mol / L) 0.01mol / L ATP 2479.16 0.99503 <![CDATA[5.57×10 -5 > 0.001mol / L TCY 13308.07 0.98771 <![CDATA[1.04×10 -5 >

[0080] The present invention further investigated the recognition of TCY and ATP by Sample 1 in different foods, and the results are shown in Table 6 and Table 7.

[0081] Table 6. Recognition performance of TCY by Sample 1 in different foods

[0082]

[0083] Table 7. Recognition performance of ATP by Sample 1 in different foods

[0084]

[0085] Figure 5 It can be seen from the ultraviolet absorption spectra of the ligand compound and the antibacterial drug that the ultraviolet absorption peaks are mainly concentrated in the 200 - 300 nm range.

[0086] From Figure 6 the excitation - emission spectrum, it can be seen that the optimal excitation of Sample 1 is 333 nm, and the main emission peak is located at 617 nm, which belongs to the 3+ D0→ 5 F2 transition of Eu 7 The other four characteristic peaks appear at 579 nm, 592 nm, 650 nm, and 686 nm, which are respectively generated by the 3+ D0→ 5 F0, 7 D0→ 5 F1, 7 D0→ 5 F3, 7 D0→ 5 F4 transitions of Eu 7 respectively.

[0087] As shown in Figure 7, it can be seen from the fluorescence screening diagram of Sample 1 against antibacterial drugs that the fluorescence intensities of CEF, SMZ, and CAP are significantly weakened, while quenching occurs for TCY, indicating that Sample 1 can be used as a potential fluorescent probe for selective recognition of TCY.

[0088] As shown in Figure 8, the quenching of TCY by the sample was studied using a concentration titration experiment. It was found that the luminescence intensity decreased while the fluorescence intensity gradually weakened with the increase in the concentration of TCY.

[0089] The fluorescence concentration titration of the sample was processed using the Stern-Volmer equation to study the relationship between the percentage of luminescence concentration quenching of the sample and the concentration of TCY, as shown in A of Figure 8. Using the linear formula I0 / I = 1 + K sv [Q], where K sv represents the fluorescence quenching constant of the sample, Q is the quenching concentration of different samples, I0 is the fluorescence intensity of the sample blank, and I is the fluorescence intensity at a certain concentration of the sample. The quenching of the fluorescence emission intensity of the sample and the concentration of TCY (from 0 to 9.09×10 -5 mol / L) showed an ideal linear relationship. Through the calculation of the Stern-Volmer linear equation, the fluorescence quenching constant (K sv ) was 13308.07, and the fluorescence detection limit (LOD) was 1.04×10 -5 mol / L. Therefore, sample 1 can be used to detect TCY molecules.

[0090] Comparing in the presence of different antibacterial drugs, it can be seen from Figure 9 that in the case of different antibacterial drugs or antibacterial drug combinations, the recognition of TCY by sample 1 is not interfered by other antibacterial drugs. Its anti-interference fluorescence cycling data Figure 10 showed that sample 1 has no adsorption effect on antibacterial drugs and has good recyclability.

[0091] In the screening test of sample 1 for biomolecules in Figure 11, it can be seen that slight fluorescence intensity quenching occurred for common biomolecules such as Ure, Ser, Met, Phe, Cys, AA, Citn, etc. Among them, the fluorescence quenching of DA and Lys was slightly more obvious, while that of ATP showed a very significant decrease in fluorescence intensity.

[0092] In the concentration titration experiment for the recognition of ATP, as Figure 12 shown, it can be seen that as the concentration of ATP (in the range of 0 - 9.09×10 -4 mol / L) increased, the fluorescence intensity gradually decreased. The quenching of its intensity and the concentration of ATP molecules showed a good linear relationship. The quenching constant was 2479.16, and the LOD was 5.57×10 -5 mol / L.

[0093] In the anti-interference experiment for cations, as Figure 13 shown, it can be seen that other common biomolecules cannot interfere with the detection of ATP by sample 1, and the cycling test, as Figure 14As shown, it can be seen that Sample 1 has certain recyclability and shows little change.

[0094] The interfering factors are different in different substances. The applicant compared the detection effects of Sample 1 for TCY and ATP in deionized water and different food samples, such as tap water, eggs, milk, and honey. Through comparison with the theoretical values, the spiked recoveries (80%-120%) are met.

[0095] After the experiments of titrating TCY and ATP, XRD tests were carried out on Sample 1, and it was found that the peaks were consistent with the theoretical peaks of Sample 1, indicating that during the titration detection process, Sample 1 did not adsorb the analytes and no structural changes occurred. As Figure 15 shown.

[0096] Example 4:

[0097] Application of a Eu-based rare earth complex in the intelligent sensing of mobile phones.

[0098] As Figure 16 shown, based on the recognition performance of Sample 1 for TCY and ATP, a colorimetric sensing platform was constructed. When the actual sample was added to Sample 1, a solution with a change in fluorescence intensity could be obtained. Placing it under an ultraviolet lamp, taking a photo with a mobile phone and uploading it to the APP, the corresponding RGB values could be obtained. Substituting the obtained RGB values into the function, the concentrations of TCY and ATP within the detection range could be obtained.

[0099] Example 5:

[0100] Application of a Eu-based rare earth complex in fingerprint anti-counterfeiting.

[0101] As Figure 17 shown, to increase the practical application of Sample 1, the applicant added Sample 1 and colorless stamp ink to a blank stamp box to make a fluorescent stamp box that can be applied to fingerprint anti-counterfeiting.

[0102] In summary, the present invention synthesized a new Eu-based rare earth complex, which can be used for the detection of food pollutants such as ATP and TCY in water and food. The novel metal-organic framework compound material synthesized in the present invention has excellent luminescent properties. It can not only identify TCY among many antibiotics, but also identify the biomolecule ATP in water. It also built a mobile phone intelligent sensing platform to achieve rapid detection of TCY and ATP, and prepared a portable stamp box for anti-counterfeiting applications. The detection limit of this material for different molecules is low, which reflects the advantages of easy preparation, low cost, simple operation, high sensitivity, and high selectivity of this material.

[0103] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention. The structures, devices, and operation methods not specifically described and explained in the present invention are implemented according to the conventional means in the art without special explanation and limitation.

Claims

1. A Eu-based rare earth complex, characterized in that: The chemical formula of the Eu-based rare earth complex is [Eu2(L)3(H2O)] n , where H3L is 4-(2,4,6-tricarboxyphenyl)-3,2’:6,3”-terpyridine; the single crystal structure of this compound belongs to the orthorhombic system, the space group is C2221, and the unit cell parameters are: bond length Bond length Bond length Bond angle α = 90°, bond angle β = 90°, bond angle γ = 90°.

2. The Eu-based rare earth complex according to claim 1, characterized in that: The molecular formula of the Eu-based rare earth complex is C 72 H 41 Eu2N9O 19 ; the molecular weight of the compound is 1640.

06.

3. The Eu-based rare earth complex according to claim 2, characterized in that: The single crystal structure, unit cell volume The number of molecules Z = 4 in the unit cell, crystal density ρ calcd = 1.625 g / cm 3 , linear absorption coefficient μ = 13.951 mm –1 , the number of electrons F(000) = 3256 in the unit cell, unit cell diffraction angle range θRange = 3.5 - 68.3 deg, diffraction points collected = 34170, independent diffraction points (R int ) = 0.064, the number of diffractions with intensity greater than 2σ = 5532.

4. The preparation method of a Eu-based rare earth complex according to any one of claims 1-3, characterized in that: Mix H3L, Eu(NO3)3·6H2O and water, and stir for 15 - 45 minutes. Then transfer and seal in a reactor, heat to 160 - 180 °C, keep warm for 68 - 80 hours, and cool to room temperature to obtain the product; wherein, the molar ratio of H3L to Eu(NO3)3·6H2O is 1:1.5, and the dosage ratio of H3L to water is 0.1 mmol: 9 - 15 mL.

5. The preparation method of a Eu-based rare earth complex according to claim 4, characterized in that: The heating rate is 7 - 13 °C / h, and the cooling rate is 3 - 8 °C / h.

6. Use of a Eu-based rare earth complex according to any one of claims 1 - 3 in detecting food contaminants.

7. The application according to claim 6, wherein The food contaminants include: antibacterial drugs and biomolecules, and the antibacterial drugs and biomolecules include TCY and ATP.

8. Use of a Eu-based rare earth complex according to any one of claims 1 - 3 in the intelligent sensing of mobile phones.

9. Use of a Eu-based rare earth complex according to any one of claims 1 - 3 in fingerprint anti-counterfeiting.

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