Eu-based rare earth complex, preparation method and application thereof

Abstract

This invention belongs to the field of metal-organic framework (MOF) material application technology, specifically relating to an Eu-based rare-earth complex, its preparation method, and its application, which can be used for the detection of pollutants such as TCY and ATP in water. The novel rare-earth MOF compound synthesized in this invention exhibits significant luminescence properties, recognizing not only ATP among numerous biomolecules but also TCY molecules among various antibiotic molecules. This material demonstrates excellent fluorescence recognition performance for both molecules and good spiked recovery rates in actual samples. Based on this, a mobile phone-based intelligent sensing platform is constructed, enabling rapid sensing and detection of TCY and ATP molecules. Furthermore, based on the significant red luminescence properties of rare-earth MOF compounds under ultraviolet light, a portable stamp box is fabricated for fingerprint anti-counterfeiting.

Description

Technical Field

[0001] This invention belongs to the field of metal-organic framework materials application technology, specifically relating to an Eu-based rare earth complex, its preparation method, and its application. Background Technology

[0002] Global social development and human activities have led to a serious public health problem—water pollution. Residual drugs are classified as a form of water pollution because they are believed to cause ecological problems and have long-term, cumulative harmful effects on humans and ecosystems. Tetracycline (TCY), a broad-spectrum antibiotic, has been found to be widespread in natural waterways due to abuse and improper disposal. Environmentally residual TCY can enter the body in multiple ways, thus harming human health. Monitoring TCY levels in ecosystems or food is crucial for protecting human health.

[0003] Adenosine triphosphate (ATP) is a multifunctional nucleotide containing three negatively charged phosphate groups. It plays several important roles in cell biology, primarily as a universal energy currency and signaling molecule in living cells to coordinate responses to energy states, partly by regulating ion channels and activating signaling cascades. In addition to its role in energy metabolism and signal transduction, ATP is also incorporated into nucleic acids through polymerases during DNA replication and transcription. The concentration and dissipation rate of ATP have been found to be closely related to many diseases, such as hypoxia, hypoglycemia, ischemia, Parkinson's disease, and certain malignancies; therefore, the detection of ATP is not only of scientific significance but also of clinical importance.

[0004] Metal-organic frameworks (MOFs) are organic-inorganic hybrid crystalline materials rich in active sites and with tunable structures. They possess advantages such as structural diversity, variable properties, and mild and easy-to-manage synthesis conditions. Furthermore, due to the controllable and tunable nature of their organic ligands, MOFs exhibit advantages over traditional optical materials in fluorescence sensing and show promising application prospects in antibacterial drugs and biomolecular detection.

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

[0006] In the prior art, patent application CN117866224A discloses an Eu-MOF ratiometric fluorescent probe material, its preparation method, and its application in detecting tetracycline. This ratiometric fluorescent probe, under 365nm ultraviolet light excitation, exhibits red light emission dominated by a wavelength of 614nm. After the addition of tetracycline (TCs), it exhibits blue light emission dominated by 480nm, achieving ratiometric fluorescence detection with a low detection limit. This fluorescent probe can highly selectively identify tetracycline in aqueous solutions and also possesses advantages such as high stability, reusability, and simple operation.

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

[0008] The above-mentioned patented technologies can only be used for the detection of one of TCY and ATP, and none of them have been applied to intelligent sensing in mobile phones, lacking practical applications in anti-counterfeiting. However, with the increase of pollutants, there are very few fluorescent probes that can simultaneously detect antibacterial drugs and biomolecules. Therefore, this invention proposes an Eu-based rare earth complex, its preparation method, and its applications in fluorescence recognition, intelligent sensing in mobile phones, and anti-counterfeiting. Summary of the Invention

[0009] The purpose of this invention is to provide an Eu-based rare-earth complex, its preparation method, and its applications. The synthesized novel rare-earth metal-organic framework compound material exhibits significant luminescent properties, recognizing not only ATP among numerous biomolecules but also TCY molecules among various antibiotic molecules. This material demonstrates excellent fluorescence recognition performance for both molecules and exhibits good spiked recovery rates in actual samples. Based on this, a mobile phone-based intelligent sensing platform is constructed, enabling rapid sensing and detection of ATP and TCY molecules. Furthermore, based on the significant red luminescence properties of rare-earth metal-organic framework compounds under ultraviolet light, a portable stamp box is fabricated for fingerprint anti-counterfeiting.

[0010] The specific technical solution adopted by this invention is as follows:

[0011] An Eu-based rare earth complex, wherein the chemical formula of the Eu-based rare earth complex is [Eu2(L)3(H2O)] n H3L is 4-(2,4,6-tricarboxylic acid phenyl)-3,2':6,3”-terpyridine; the single-crystal structure of this compound belongs to the orthorhombic crystal system, space group 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°.

[0012] Preferably, the molecular formula of the Eu-based rare earth complex is C2. 72 H 41 Eu2N9O 19 The molecular weight of the compound is 1640.06.

[0013] Preferably, the single-crystal structure has a unit cell volume of Number of molecules in unit cell Z = 4, crystal density ρ calcd =1.625g / cm 3 The linear absorption coefficient μ = 13.951 mm. –1 Number of electrons in unit cell F(000) = 3256, diffraction angle range θRange = 3.5-68.3 degrees, diffraction point collection = 3417°, independent diffraction points (R int =0.064, and the number of diffractions with an intensity greater than 2σ is 5532.

[0014] A method for preparing an Eu-based rare earth complex involves mixing H3L, Eu(NO3)3·6H2O, and water and stirring for 15–45 minutes. The mixture is then transferred to a reactor and sealed. The reactor is heated to 160–180°C at a rate of 7–13°C / h and held at that temperature for 68–80 hours. The mixture is then cooled to room temperature at a rate of 3–8°C / h. The molar ratio of H3L to Eu(NO3)3·6H2O is 1:1.5, and the volume ratio of H3L to water is 0.1 mmol: 9–15 mL.

[0015] Application of an Eu-based rare earth complex in the detection of food contaminants, said food contaminants including antimicrobial agents and biomolecules, said antimicrobial agents and biomolecules including TCY and ATP.

[0016] Application of an Eu-based rare earth complex in smart sensing in mobile phones.

[0017] Application of an Eu-based rare earth complex in fingerprint anti-counterfeiting.

[0018] The technical effects achieved by this invention are as follows:

[0019] This invention synthesizes a novel Eu-based rare-earth complex that can be used to detect food contaminants such as TCY and ATP in water and food. The novel metal-organic framework compound synthesized in this invention exhibits excellent luminescent properties, recognizing not only TCY among numerous antibiotics but also the biomolecule ATP in water. Furthermore, a mobile phone-based intelligent sensing platform has been developed for rapid detection of TCY and ATP, and a portable stamp box has been fabricated for anti-counterfeiting applications. The material exhibits low detection limits for different molecules, demonstrating its advantages of convenient preparation, low cost, simple operation, high sensitivity, and high selectivity. Attached Figure Description

[0020] Figure 1 The chemical structural formula of the ligand of the Eu-based rare earth complex (sample 1) of the present invention is shown below.

[0021] Figure 2 Infrared (A) and thermogravimetric (B) analyses of sample 1 of the present invention;

[0022] Figure 3 The X-ray diffraction pattern is for a single crystal.

[0023] Figure 4 shows the crystal structure of the single crystal, where A is the coordination environment diagram of sample 1 and B is the 3D network structure of sample 1.

[0024] Figure 5 The UV absorption spectra of the main ligand and sample 1, as well as different antibiotic molecules and biomolecules;

[0025] Figure 6 Excitation and emission spectra of sample 1;

[0026] Figure 7 shows the antimicrobial drug detection results for sample 1, where A is a curve graph and B is a bar graph.

[0027] Figure 8 shows the titration of antibacterial drug concentration for sample 1, where A is the fitting graph and B is the curve graph.

[0028] Figure 9 This is an anti-interference bar chart of sample 1 for antimicrobial drug detection;

[0029] Figure 10 This is a comparison graph of fluorescence cycling data of sample 1 against antibacterial drugs;

[0030] Figure 11 shows the screening of biomolecules, where A is a curve graph and B is a bar graph;

[0031] Figure 12 To identify biomolecule concentration titrations, A is a fitted graph and B is a curve graph;

[0032] Figure 13 This is a bar chart showing the resistance to interference from biomolecules.

[0033] Figure 14 A comparison graph of fluorescence cycling data for biomolecules;

[0034] Figure 15 For XRD comparison before and after titration;

[0035] Figure 16 Flowchart of mobile phone intelligent sensing;

[0036] Figure 17 The manufacturing process of anti-counterfeiting stamp boxes. Detailed Implementation

[0037] To make the objectives and advantages of this invention clearer, the invention will be specifically described below with reference to embodiments. It should be understood that the following text is merely used to describe one or more specific embodiments of the invention and does not strictly limit the scope of protection specifically claimed by the invention.

[0038] Example 1:

[0039] An Eu-based rare earth complex, wherein the chemical formula of the Eu-based rare earth complex is [Eu2(L)3(H2O)] n H3L is 4-(2,4,6-tricarboxylic acid phenyl)-3,2':6,3”-terpyridine; the single-crystal structure of this compound belongs to the orthorhombic crystal system, space group 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°. Chemical structural formula as follows: Figure 1 As shown.

[0040] Preferably, the molecular formula of the Eu-based rare earth complex is C2. 72 H 41 Eu2N9O 19 The molecular weight of the compound is 1640.06.

[0041] Preferably, the single-crystal structure has a unit cell volume of Number of molecules in unit cell Z = 4, crystal density ρ calcd =1.625g / cm 3 The linear absorption coefficient μ = 13.951 mm. –1 Number of electrons in unit cell F(000) = 3256, diffraction angle range θRange = 3.5-68.3 degrees, diffraction point collection = 3417°, independent diffraction points (R int =0.064, and the number of diffractions with an intensity greater than 2σ is 5532.

[0042] Example 2:

[0043] A method for preparing an Eu-based rare earth complex involves mixing H3L, Eu(NO3)3·6H2O, and water and stirring for 15–45 minutes. The mixture is then transferred to a reactor and sealed. The reactor is heated to 160–180°C at a rate of 7–13°C / h and held at that temperature for 68–80 hours. The mixture is then cooled to room temperature at a rate of 3–8°C / h. The molar ratio of H3L to Eu(NO3)3·6H2O is 1:1.5, and the volume ratio of H3L to water is 0.1 mmol: 9–15 mL.

[0044] In the actual synthesis, 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 Teflon-lined reactor, heated to 180 °C, held at that temperature for 72 hours, and then cooled to room temperature at a rate of 5 °C / h. Colorless bulk crystals, calculated based on europium, were obtained, designated as Sample 1, with a yield of 65%. H3L was 4-(2,4,6-tricarboxylic acid phenyl)-3,2':6,3”-terpyridine.

[0045] Characterization data of Eu-based rare earth complexes in this invention: elemental analysis results of sample 1 are shown in Table 1; crystal data are shown in Table 2; selected bond lengths and bond angles are shown in Table 3; 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 this invention:

[0060] X-ray single-crystal structure analysis revealed that Sample 1 is composed of an orthorhombic crystal system, space group C2221, exhibiting a three-dimensional layered shale structure. Analysis of the central ion coordination environment showed that Sample 1 possesses good symmetry and stability. Based on the coordination environment diagram of Sample 1, as shown... Figure 1 As shown, the asymmetric coordination environment unit contains two Eu atoms. 3+ Three oxygen-containing L 3- The sample contains a ligand anion and one coordinated water molecule. EuO1 in sample 1 is associated with five 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 antitrigonal prism, in which L 3- The ligands O3 and O9 are located at the equator, while O4, O5, and O6 are located along the axis. EuO2 and four L... 3- The ligands and the 10 oxygen atoms of the water molecule (O1, O1', O2, O2', O7, O7', O10, O10', O11, O11') also form a 10-coordinated double-capped tetragonal antitrigonal prism, in which L 3- The ligands O1, O10, and O11 are located in the axial position, while the remaining atoms are located in the equatorial position.

[0061] metal Eu 3+ With L 3- The oxycarboxylic acid coordination anion adopts a bidentate bridging coordination (coordination mode μ3-η). 2 :η 2 :η 2 The Eu-O bonds in the structure have advantages in... The O-Eu-O bond angle is in the range of 47.2(6) to 166.8(3)°. In the structure of sample 1, due to Eu... 3+ Center and L 3- The oxygen-containing ligand anion has two different coordination sites, in its structure, L 3- A 1D chain structure of grid is formed by "hand in hand" along the a-axis using Eu01, and a 2D structure is formed by stacking Eu01 along the b-axis. A 3D structure is then formed by stacking Eu02 along the c-axis.

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

[0063] See Figure 2 In sample B, there is a first-step weight loss in the range of 85.9-182.9℃. This is because when the free water in the sample reaches 481.9℃, the backbone of the organic ligand molecules in the sample begins to collapse until the sample finally decomposes into oxides.

[0064] See Figure 3 The results show that within the range of 5-50 (2θ), the theoretical data plot and the experimentally measured plot of the sample show consistent peak shapes and 2θ positions in XRD, 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, and 24.20.

[0065] Example 3:

[0066] Application of an Eu-based rare earth complex in the detection of food contaminants, said food contaminants including antimicrobial agents and biomolecules, said antimicrobial agents and biomolecules including TCY and ATP.

[0067] In this invention, Eu-based rare earth complexes were used in antibacterial drug recognition experiments.

[0068] In experiments involving Sample 1 and the antibacterial drugs chloramphenicol (CAP), sulfadiazine (SDZ), sulfamethoxazole (SMT), thiamphenicol (THI), sulfadiazine (SMZ), ibuprofen (IPF), amoxicillin (AMXL), imipenem nucleus (IMP), cefixime (CEF), indomethacin (IMC), and tetracycline (TCY), it was found that Sample 1 exhibits sensing properties against the TCY antibacterial drug. For the sensing experiment, Sample 1 (1 mg / mL) was prepared by suspending 5 mg of powder in 5 mL of water and then ultrasonically stirring the mixture for 30 minutes before testing. -1The sample was a dispersion of 1 sample. Titration experiments were performed by stepwise addition of the antibacterial drug aqueous solution to the aqueous dispersion of sample 1. All experiments were repeated for four cycles. The quenching efficiency was calculated as [(I0-I) / I0]×100%, where I0 and I are the fluorescence intensities before and after the addition of the analyte. These competitive experiments were performed by adding 2.5 mL of TCY aqueous solution (1×10⁻⁶) to the sample. -3 M) was added to 2.5 mL of the other molecular aqueous solution (1 × 10⁻⁶). -3 It was carried out in M).

[0069] In this invention, Eu-based rare earth complexes are used in biomolecular recognition experiments:

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

[0071] The results of the aforementioned experiments are shown in Table 5 below:

[0072] 1. Antibacterial drug experiment:

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

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

[0075] 2. Biomolecular experiments:

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

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

[0078] Table 5. Identification of antimicrobial agents, cations, and anions in Sample 1

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

[0080] The present invention further identifies TCY and ATP in samples 1 of different foods, and the results are shown in Tables 6 and 7.

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

[0082]

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

[0084]

[0085] Figure 5 The ultraviolet absorption spectra of ligand compounds and antibacterial drugs show that the ultraviolet absorption peaks are mainly concentrated in the 200-300 nm range.

[0086] from Figure 6 The excitation-emission diagram shows that the optimal excitation for sample 1 is 333 nm, and the main emission peak is located at 617 nm, which belongs to Eu. 3+ of 5 D0→ 7 The F2 transition produces the peaks, while the other four characteristic peaks appear at 579nm, 592nm, 650nm, and 686nm, respectively, and are generated by Eu. 3+ of 5 D0→ 7 F0、 5 D0→ 7 F1 5 D0→ 7 F3 5 D0→ 7 The F4 transition occurs.

[0087] As shown in Figure 7, the fluorescence screening diagram of sample 1 against antibacterial drugs shows that the fluorescence intensity of CEF, SMZ, and CAP is significantly reduced, while TCY is quenched, indicating that sample 1 can be used as a potential fluorescent probe to selectively identify TCY.

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

[0089] The relationship between the percentage of fluorescence quenching and the concentration of TCY was analyzed in the fluorescence concentration titration of the sample using the Stern-Volmer equation, as shown in Figure 8A. The linear formula I0 / I = 1 + K was then used. sv [Q], where K sv The constant represents the fluorescence quenching constant of the sample, Q represents different sample quenching concentrations, I0 represents the fluorescence intensity of the blank sample, and I represents the fluorescence intensity of the sample at a certain concentration. The quenching of sample fluorescence intensity is related to the concentration of TCY (from 0 to 9.09 × 10⁻⁶). -5 The fluorescence quenching constant (K mol / L) is an ideal linear relationship. Calculations using the Stern-Volmer linear equation show that the fluorescence quenching constant (K mol / L) is... sv The limit of fluorescence detection (LOD) was 1.04 × 10⁻⁶, and the limit of fluorescence detection (LOD) was 13308.07. -5 mol / L. Therefore, sample 1 can be used to detect TCY molecules.

[0090] Comparing the effects of different antibacterial drugs in the presence of... Figure 9 As can be seen, under different antibacterial drugs or combinations of antibacterial drugs, the recognition of TCY by Sample 1 is not affected by other antibacterial drugs. Its anti-interference fluorescence cycling data... Figure 10 As shown, sample 1 has no adsorption effect on antibacterial drugs and has good recyclability.

[0091] As shown in Figure 11 of the screening test of biomolecules in Sample 1, a slight quenching of fluorescence intensity occurred for common biomolecules such as Ure, Ser, Met, Phe, Cys, AA, and Citn. Among them, the fluorescence quenching of DA and Lys was slightly obvious, while ATP showed a very obvious decrease in fluorescence intensity.

[0092] In titration experiments to identify the concentration of ATP, such as Figure 12 As shown, it can be seen that with ATP (in the range of 0-9.09×10), -4 As the concentration of ATP molecules increases within the range of mol / L, the fluorescence intensity gradually decreases. The quenching of the intensity shows a strong linear relationship with the ATP molecule concentration, with a quenching constant of 2479.16 and a LOD of 5.57 × 10⁻⁶. -5 mol / L.

[0093] Anti-interference experiments on cations, such as Figure 13 As shown, other common biomolecules do not interfere with the detection of ATP in sample 1, while cyclic assays, such as... Figure 14As shown, it can be seen that sample 1 has a certain degree of recyclability and its performance remains almost unchanged.

[0094] Different substances have different interfering factors. The applicant compared the detection effects of sample 1 on TCY and ATP in deionized water and different food samples, such as tap water, eggs, milk and honey. By comparing with the theoretical values, the results were consistent with the spiked recovery rate (80%-120%).

[0095] After titration experiments with TCY and ATP, XRD analysis was performed on sample 1. The results showed that the elution peaks were consistent with the theoretical peak values ​​for sample 1, indicating that sample 1 did not adsorb the analyte during the titration process and no structural changes occurred. Figure 15 As shown.

[0096] Example 4:

[0097] Application of an Eu-based rare earth complex in smart sensing in mobile phones.

[0098] like Figure 16 As shown, based on the recognition performance of Sample 1 for TCY and ATP, a colorimetric sensing platform was constructed. When the actual sample is added to Sample 1, a solution with changing fluorescence intensity can be obtained. The solution is placed under a UV lamp, and a photo is taken with a mobile phone and uploaded to an APP to obtain the corresponding RGB values. Substituting the obtained RGB values ​​into a function, the concentrations of TCY and ATP within the detection range can be obtained.

[0099] Example 5:

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

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

[0102] In summary, this invention synthesizes a novel Eu-based rare-earth complex that can be used to detect food contaminants such as ATP and TCY in water and food. The novel metal-organic framework compound synthesized in this invention exhibits excellent luminescent properties, capable of recognizing not only TCY among numerous antibiotics but also the biomolecule ATP in water. Furthermore, a mobile phone-based intelligent sensing platform has been developed for rapid detection of TCY and ATP, and a portable stamp box has been fabricated for anti-counterfeiting applications. The material demonstrates low detection limits for different molecules, highlighting its advantages of convenient preparation, low cost, simple operation, high sensitivity, and high selectivity.

[0103] The above description is merely a preferred embodiment of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention. Structures, devices, and operating methods not specifically described or explained in this invention are implemented according to conventional methods in the art unless otherwise specified or limited.

Claims

1. An Eu-based rare earth complex, characterized in that: The chemical formula of the Eu-based rare earth complex is [Eu2(L)3(H2O)]. n H3L is 4-(2,4,6-tricarboxylic acid phenyl)-3,2':6,3''-terpyridine; the single-crystal structure of this complex belongs to the orthorhombic crystal system, space group 1. C222 1 The unit cell parameters are: bond length a =13.6037(2) Å, bond length b =32.0561(4) Å, bond length c =15.3740(2)Å, bond angle α =90°, bond angle β =90°, bond angle γ =90°; The molecular formula of the Eu-based rare earth complex is C 72 H 41 Eu2N9O 19 The molecular weight of the complex is 1640.

06.

2. The Eu-based rare earth complex according to claim 1, characterized in that: The single crystal structure, unit cell volume V =6704.32(16) Å 3 Number of molecules in a unit cell Z =4, crystal density ρ calcd =1.625g / cm 3 The linear absorption coefficient µ = 13.951 mm –1 Number of electrons in a unit cell F (000) = 3256, cell diffraction angle range θ Range = 3.5-68.3deg, diffraction point collection = 34170, independent diffraction points ( R int =0.064, the number of diffractions with intensity greater than 2σ = 5532.

3. A method for preparing an Eu-based rare earth complex according to any one of claims 1-2, characterized in that: Mix H3L, Eu(NO3)3·6H2O and water and stir for 15–45 minutes. Then transfer and seal the mixture in a reactor, heat to 160–180 °C, keep at that temperature for 68–80 hours, and cool to room temperature to obtain the final product. The molar ratio of H3L to Eu(NO3)3·6H2O is 1:1.5, and the volume ratio of H3L to water is 0.1 mmol: 9–15 mL.

4. The method for preparing an Eu-based rare earth complex according to claim 3, characterized in that: The heating rate is 7–13℃ / h, and the cooling rate is 3–8℃ / h.

5. The application of an Eu-based rare earth complex according to any one of claims 1-2 in the detection of food contaminants.

6. The application according to claim 5, characterized in that, The food contaminants include: antimicrobial agents and biomolecules, wherein the antimicrobial agents include tetracycline (TCY); and the biomolecules include adenosine triphosphate (ATP).

7. The application of an Eu-based rare earth complex as described in any one of claims 1-2 in the intelligent sensing of a mobile phone.

8. The application of an Eu-based rare earth complex as described in any one of claims 1-2 in fingerprint anti-counterfeiting.

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