Preparation method and application of MOF material-based SERS substrate

Abstract

The application provides a preparation method of a MOF material-based SERS substrate and application thereof, and belongs to the technical field of SERS substrate preparation. The MOF material of ZIF-8 is prepared by using a hydrothermal method, then AuNPs cores are coated in the ZIF-8 shell by using an electrostatic assembly method, and a core-shell material Au@ZIF-8 is prepared as a SERS substrate. The method for preparing the SERS substrate is simple and effective, and interference of reagents except water phase on SERS detection target small molecules is avoided. The MOF surface of the MOF material-based SERS substrate prepared by the application has uniform and adjustable size pore structures, can selectively allow only the to-be-detected small molecules to pass, and realizes detection of adenosine triphosphate in urine.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of SERS substrate preparation, in particular to a preparation method of a SERS substrate based on a MOF material and application thereof. BACKGROUND

[0002] Adenine nucleotide triphosphate (ATP for short) is an unstable high-energy compound composed of one molecule of adenine, one molecule of ribose and three molecules of phosphate groups. Adenine nucleotide triphosphate is a coenzyme that has the effect of improving the metabolism of the body and participates in the metabolism of fat, protein, sugar, nucleic acid and nucleotide in the body. At the same time, adenosine triphosphate is also the main source of energy in the body. When the body needs energy for absorption, secretion, muscle contraction and biochemical synthesis reaction, adenosine triphosphate is decomposed into adenosine diphosphate and phosphate groups, and energy is released at the same time. Under normal physiological conditions, the ATP level in cells is maintained within a relatively stable range. Imbalance of ATP homeostasis, that is, the balance between ATP synthesis and decomposition is broken, which can lead to insufficient or excessive energy supply of cells, and further affect the normal physiological function of cells. ATP disorder is closely related to many diseases in clinical practice. First, during the inflammatory process, immune cells release a large amount of ATP as a signal molecule to participate in the regulation of immune response and inflammatory process. When the inflammatory process is out of control, the release and metabolism of ATP can be affected, leading to imbalance of ATP homeostasis. Secondly, symptoms such as hypoglycemia and ischemia can lead to insufficient energy supply of cells, and further affect the synthesis and supply of ATP. Under this condition, the ATP level in cells will decrease, which cannot meet the normal physiological needs, thereby causing a series of metabolic disorders and cell damage.

[0003] At present, there are many methods for detecting ATP, such as colorimetric method, bioluminescence method, electrochemical analysis method and high performance liquid chromatography method, but these methods generally have the limitations of high complexity, tedious sample processing procedure and long time-consuming. Therefore, they are not suitable for the rapid detection requirement of ATP. Therefore, it is very meaningful to find a detection method with high sensitivity and good selectivity to detect ATP.

[0004] Surface enhanced Raman scattering (SERS) technology is a highly efficient detection method, which relies on the significant enhancement of Raman scattering signals of molecules near the surface of a specific active substrate, has the advantages of high sensitivity, fast analysis speed and simple operation, and can realize the detection of molecules in trace or even ultratrace samples. Traditional SERS substrates have the disadvantages of poor stability and non-obvious Raman signal enhancement, therefore, it has become a hot issue in the field of SERS research to construct stable and accurate Raman enhancement signals.

[0005] Metal-organic frameworks (MOFs) are a new class of porous materials constructed from the exquisite combination of metal ions / clusters and organic bridging ligands, exhibiting unique structures and properties. Their unique chemical composition, precise crystal arrangement, and special pore structure endow them with numerous unique advantages. ZIFs in MOF materials have high specific surface area and adjustable pore size. The porous structure formed by van der Waals forces, electrostatic and π-π interactions can protect nanoparticles from aggregation, and they have great application potential in gas adsorption, separation, storage, and catalysis. In particular, ZIFs perform well in carbon dioxide capture and storage, hydrogen storage, and organic solvent adsorption and separation. In addition, ZIFs can be functionally modified, such as introducing specific functional groups or active sites, to enhance their performance in specific applications. Moreover, they can also adsorb analytes for enrichment, providing an effective means for the separation, analysis and detection of target substances. SUMMARY

[0006] Therefore, the purpose of the present application is to provide a preparation method of a SERS substrate based on MOF materials, which is simple, time-saving, economical and easy to obtain, and does not require complicated sample pretreatment steps, and can realize trace detection of adenosine triphosphate in urine.

[0007] The preparation method of the SERS substrate based on MOF materials according to the present application comprises the following steps:

[0008] (1) Synthesis of ZIF-8: prepare a methanol solution of zinc nitrate hexahydrate and a methanol solution of 2-methylimidazole, respectively; mix the two solutions and stand, to produce white precipitate;

[0009] Collect the white precipitate and ultrasonically dissolve it in methanol 、 Centrifuge, then wash with methanol and distilled water alternately for 3-4 times, and dry to obtain the MOF material of ZIF-8;

[0010] (2) Synthesis of AuNPs: heat the chloroauric acid solution to boiling, quickly add the trisodium citrate solution, stop heating after 10-12 min, continue stirring the solution to room temperature, and store at 4-10℃ to obtain the AuNPs solution;

[0011] (3) Preparation of AuNPs@ZIF-8 particles: dissolve the MOF material of ZIF-8 prepared in step (1) in the AuNPs solution prepared in step (2) and stir, then centrifuge the mixed solution and repeat 2-3 times to obtain the AuNPs@ZIF-8 particle sol;

[0012] (4) Preparation of SERS substrate: add the AuNPs@ZIF-8 sol to ultrapure water and ultrasonically dissolve it as the substrate.

[0013] Preferably, the concentration of zinc nitrate hexahydrate in the methanol solution of zinc nitrate hexahydrate in step (1) is 0.08-0.1 g / mL; and the concentration of 2-methylimidazole in the methanol solution of 2-methylimidazole is 0.06-0.07 g / mL.

[0014] Preferably, the volume ratio of the methanol solution of zinc nitrate hexahydrate to the methanol solution of 2-methylimidazole in step (1) is 15-25:55-65.

[0015] Preferably, the mixing in step (1) is ultrasonic mixing, and the mixing time is 1-1.25 h; and the standing time is 18-24 h.

[0016] Preferably, the centrifugal speed in step (1) is 10000 rpm, and the centrifugal time is 5-8 min.

[0017] Preferably, the mass concentration of the chloroauric acid solution in step (2) is 0.01-0.02%, the mass concentration of the trisodium citrate solution is 1-1.5%, and the volume ratio of the chloroauric acid solution to the trisodium citrate solution is 100:1-3.

[0018] Preferably, the heating temperature in step (2) is 110-120℃; the stirring speed before heating and boiling is 100-150 rpm, the stirring speed after heating and boiling is 500-600 rpm, and the trisodium citrate solution is quickly added.

[0019] Preferably, the mass-volume ratio of the MOF material of ZIF-8 to the AuNPs solution in step (3) is 13-15 mg:10 mL.

[0020] Preferably, the stirring time in step (3) is 10-12 h; and the centrifugal speed is 5000-5500 rpm.

[0021] Another object of the present application is to provide an application of the MOF material-based SERS substrate prepared by the above method, which is used for adenosine triphosphate detection.

[0022] Compared with the prior art, the present application has the following beneficial effects:

[0023] The application provides a preparation method and application of a SERS substrate based on MOF materials. The MOF material of ZIF-8 is prepared by a hydrothermal method, and then AuNPs (nucleus) are coated in ZIF-8 (shell) by an electrostatic assembly method to prepare a core-shell material (Au@ZIF-8). The method for preparing the SERS substrate is simple and effective, and interference of reagents other than the aqueous phase on the SERS detection target small molecules is avoided. The MOF surface of the SERS substrate based on the MOF material prepared by the application has uniform and adjustable pore structure, and can selectively allow the to-be-detected small molecules to pass through, so that detection of adenosine triphosphate in urine is realized. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 Optical pictures of the Au@ZIF-8 substrate prepared in Example 1 before and after centrifugal concentration;

[0025] Figure 2 Fourier infrared (FT-IR) characterization diagrams of ZIF-8 and Au@ZIF-8 of ZIF-8 and Au@ZIF-8;

[0026] Figure 3 SEM scanning results of Au@ZIF-8 prepared in Example 1;

[0027] Figure 4 SEM scanning results of ZIF-8 in Example 1;

[0028] Figure 5 TEM characterization analysis results of Au@ZIF-8 prepared in Example 1;

[0029] Figure 6 TEM characterization analysis results of ZIF-8 in Example 1;

[0030] Figure 7 SERS signal intensity of MG at 1373 cm -1 of the SERS substrate of Example 1 at different concentrations;

[0031] Figure 8 Corresponding relationship between the SERS substrate signal intensity and the concentration of Example 1;

[0032] Figure 9 Intensity of the characteristic peak of MG at 1373 cm -1 of the SERS substrate of Example 1 randomly sampled at 20 different test points;

[0033] Figure 10 Relative standard deviation (RSD) of the SERS substrate of Example 1 randomly sampled at 20 different test points;

[0034] Figure 11 SERS enhancement effect diagram of Au@ZIF-8 substrate of Example 1 for ATP concentration of 10 -2 mol / L;

[0035] Figure 12 SERS enhancement effect comparison diagram of Au@ZIF-8 substrate of Example 1 for different concentrations (ATP 10 -3 -10 -7 mol / L);

[0036] Figure 13 SERS enhancement effect diagram of ethyl acetate extracted urine for ATP concentration of 10 -5 mol / L;

[0037] Figure 14 SERS enhancement effect comparison diagram of ethyl acetate extracted urine for ATP concentration of 10 -3 -10 -7 mol / L;

[0038] Figure 15 SERS intensity value at 1373 cm -1 -1 of SERS substrate of Example 1 and its concentration relationship diagram of adenosine triphosphate;

[0039] Figure 16 Linear relationship diagram of SERS peak intensity value at 1373 cm -1 -1 of SERS substrate of Example 1 and adenosine triphosphate concentration;

[0040] Figure 17 Spectrum diagram of SERS active substrate of AuNPs@ZIF-8 in Example 1 for detecting ATP in urine sample;

[0041] Figure 18 Spectrum diagram of SERS active substrate of Ag@ZIF-8 in Comparative Example 2 for detecting ATP in urine sample;

[0042] Figure 19 SERS enhancement effect comparison diagram of Ag ATP 10 -7 mol / L and AuNPs@ZIF-8 ATP 10 -7 mol / L;

[0043] Figure 20 SERS enhancement effect comparison diagram of Ag@ZIF-8 ATP 10 -7 mol / L and AuNPs@ZIF-8 ATP 10 -7 mol / L. DETAILED DESCRIPTION

[0044] The application is further described below in conjunction with examples. In the specific examples of the application, the methods not specifically described are conventional methods in the art.

[0045] Example 1

[0046] A method for preparing a SERS substrate based on MOF material, the steps are as follows:

[0047] (1) Synthesis of ZIF-8: weigh 1.68 g of zinc nitrate hexahydrate and dissolve it in 20 mL of methanol, weigh 4.00 g of 2-methylimidazole and dissolve it in 60 mL of methanol, respectively, and obtain a clear solution by ultrasonic dissolution; then mix the two solutions by ultrasonic mixing at room temperature for 1 h and stand for 24 h to produce a white precipitate; collect the white precipitate, ultrasonically dissolve it in methanol, separate by centrifugation (10000 rpm, 5 min), and wash with methanol and distilled water alternately 4 times, and dry to obtain ZIF-8;

[0048] (2) Synthesis of AuNPs: heat and stir (100 rpm) 100 mL of 0.01% chloroauric acid solution, set the heating temperature to 120°C; after boiling the solution, adjust the stirrer to vigorous stirring (500 rpm), and at the same time quickly add 1 mL of 1% trisodium citrate solution, 10 s later the color of the solution changes in turn to gray, black, blue, and finally gradually stabilizes at purple red, turn off the heat source after 10 min, continue to stir the solution to room temperature, and store in the refrigerator to obtain AuNPs;

[0049] As the reduction reaction proceeds, gold atoms gradually form small AuNPs. The size and shape of these AuNPs will affect the SPR properties, resulting in changes in the color of the solution. The solution first turns gray, then black, and then blue. These color changes reflect the different size and shape distribution of gold nanoparticles during the formation process. Finally, as the reaction continues and the particle size homogenizes, the color of the solution gradually stabilizes at purple red. Turn off the heat source after the color is stable for 10 minutes, continue to stir to room temperature, and store in the refrigerator at 4°C.

[0050] (3) Preparation of AuNPs@ZIF-8 particles: dissolve ZIF-8 (13.6 mg) in 10 mL of AuNPs (0.1 nM) and stir for 12 h; then collect the mixed solution three times by centrifugation (5000 rpm) to remove excess AuNPs, and obtain AuNPs@ZIF-8 particle sol, which is stored at 4°C for use;

[0051] (4) Preparation of SERS substrate: add the AuNPs@ZIF-8 sol to 10 mL of ultrapure water, ultrasonically dissolve it, and use it as a substrate.

[0052] Comparative Example 1

[0053] A method for preparing a SERS substrate, the steps are as follows:

[0054] (1) 2 mL of AgNO3 (0.1 mol / L) solution and 198 mL of ultrapure water were added to a clean 250 mL three-necked flask, stirred on a temperature-controlled magnetic stirrer, and heated with an oil bath (150°C) to reflux; when the solution boiled, 8 mL of tannic acid (0.1 mol / L) was quickly added, and the color of the solution gradually changed from colorless to light yellow, then to khaki, and finally to gray-green; after 1 h, the heating was stopped, and after cooling, a sealed three-necked flask was used to obtain a silver nanosol, which was stored in the dark for later use.

[0055] (2) The silver nanosol was placed in a centrifuge tube and centrifuged at 25°C and 10,000 r / min for 10 min. The supernatant was removed, and the concentrated silver nanosol was obtained. The centrifuged silver nanosol was mixed together, and an equal amount of KI (0.1 mol / L) solution was added to remove the influence of impurities on the surface of the silver nanoparticles. After mixing and standing for 20 min, AgATP was obtained and stored at 4°C for use.

[0056] (4) Preparation of a SERS substrate: the AgATP was added to 10 mL of ultrapure water, and after ultrasonic dissolution, it was used as a substrate.

[0057] Comparative Example 2

[0058] A method for preparing a SERS substrate, the steps are as follows:

[0059] First, ZIF-8 was synthesized according to the method in Example 1, and 400 mg of dried ZIF-8 was added to a beaker containing 200 ml of methanol to prepare a uniform ZIF-8 suspension. Then 5 ml of AgNO3 with a concentration of 14 mg / ml was added to the ZIF-8 suspension, and stirring was continued at room temperature for about 24 h. After stirring, the suspension was poured into a 10 ml centrifuge tube, ultrasonic dispersion was performed, and the Ag-Zn-MOF product was collected by centrifugation (10000 rpm for 5 min). The obtained Ag-Zn-MOF gray powder was then poured into a beaker containing 200 ml of methanol, and 80 mg of sodium borohydride was added. After stirring, the liquid was placed in a polytetrafluoroethylene liner, and the drying oven was adjusted to 120°C for 1 h. After the reaction was completed, the yellow-green solid particles were collected by ultrasonic dispersion and centrifugation (10000 rpm, 5 min) in a 10 ml centrifuge tube, and Ag@ZIF-8 was obtained.

[0060] (4) Preparation of SERS substrate: The Ag@ZIF-8 was added into 10 mL ultrapure water and dissolved by ultrasonic to be used as substrate.

[0061] The SERS substrate prepared in Example 1 and Comparative Examples 1-2 was tested as follows:

[0062] 1. Characterization of SERS substrate of AuNPs@ZIF-8

[0063] The AuNPs@ZIF-8 particle sol prepared in Example 1 was dissolved in 10 mL ultrapure water to obtain a SERS substrate, which was characterized. The optical pictures of the Au@ZIF-8 substrate before (A) and after (B) centrifugal concentration are as follows: Figure 1 .

[0064] The infrared spectrum of AuNPs@ZIF-8 and ZIF-8 prepared in Example 1 was detected to obtain the FT-IR spectra of ZIF-8 and Au@ZIF-8 as follows: Figure 2 ;

[0065] The SEM scanning results of Au@ZIF-8 prepared in Example 1 are as follows: Figure 3 , the SEM scanning results of ZIF-8 are as follows: Figure 4 , the transmission electron microscope (TEM) results of Au@ZIF-8 prepared in Example 1 are as follows: Figure 5 , and the TEM characterization analysis results of ZIF-8 are as follows: Figure 6 ; it can be seen from Figures 3-6 that the synthesized Au@ZIF-8 core-shell structure generally presents a single core morphology, which is in the form of rhombic dodecahedron. The morphology of the samples of Au@ZIF-8 and ZIF-8 was characterized by TEM, and it can be observed that the AuNPs in the Au@ZIF-8 substrate are well dispersed, and the size of the nanoparticles used to construct the Au@ZIF-8 core-shell structure is relatively uniform.

[0066] 2. Sensitivity detection of Au@ZIF-8: Using malachite green as a SERS molecular probe, the SERS sensitivity and reproducibility of the synthesized Au@ZIF-8 substrate were detected, and the SERS signal intensity results of MG at 1373 cm -1 at different concentrations are as follows: Figure 7 ; the corresponding relationship between the substrate signal intensity and its concentration is as follows: Figure 8 . Figure 7 and Figure 8 show the SERS detection spectrum of MG molecules with a concentration from 1×10 -6 to 1×10 -8 mol / L, and it can be clearly observed from Figure 7 that the SERS spectrum of MG at 1373 cm-1 There is a significant Raman peak, which is caused by the C—H in-plane bending vibration on the aromatic ring. As the concentration of malachite green decreases, we can observe that the intensity of the characteristic peak at 1373 cm -1 also gradually decreases. Even when the concentration of MG is 1×10 -8 mol / L, the characteristic peak can still be clearly seen.

[0067] 3. Reproducibility test of Au@ZIF-8: In order to evaluate the reproducibility of Au@ZIF-8, we used SERS technology to test the solution of 1×10 -6 mol / L MG, randomly selected 20 different positions for data collection, and obtained the intensity of the characteristic peak of MG at 1373 cm -1 as shown in Figure 9 , and the relative standard deviation (RSD) of MG as shown in Figure 10 . The RSD value is 11.73%, and the synthesized Au@ZIF-8 substrate has good reproducibility.

[0068] 4. Evaluate the feasibility of directly detecting adenosine triphosphate in urine by SERS substrate

[0069] In order to verify whether the MOF SERS substrate prepared in Example 1 can be used for direct detection of adenosine triphosphate in urine, the present application compares the SERS spectra of ATP at different concentrations, taking 1×10 -2 mol / L ATP as the standard solution, and SERS detection of ATP molecules with concentrations from 1×10 -3 ×10 -7 mol / L. The SERS enhancement effect of the Au@ZIF-8 substrate of Example 1 on ATP with a concentration of 10 -2 mol / L is shown in Figure 11 ; and the comparison chart of SERS enhancement effect on different concentrations (ATP 10 -3 -10 -7 mol / L) is shown in Figure 12 . Figure 11 and Figure 12 The ATP fingerprint characteristic peak can be clearly seen, and the peak value is at 1373 cm -1 , which belongs to the breathing vibration of the adenine ring; the existence and clarity of the characteristic peak prove that the Au@ZIF-8 substrate can effectively enhance the Raman signal of ATP molecules, making it possible to detect ATP.

[0070] 5. SERS detection of adenosine triphosphate at different concentrations in urine

[0071] After the urine is extracted with ethyl acetate, the concentration of ATP in the urine is 1×10 -5mol / L ATP through SERS technology, and the concentration of ATP in urine after ethyl acetate extraction is 10 -5 mol / L ATP, as shown in the SERS enhancement effect comparison chart of Figure 13 ; the SERS enhancement effect of 10 -3 -10 -7 mol / L ATP, as shown in the SERS enhancement effect comparison chart of Figure 14 ; the SERS intensity value of AuNPs@ZIF-8 SERS substrate to adenosine triphosphate at 1373cm -1 , as shown in the SERS intensity value of AuNPs@ZIF-8 SERS substrate to adenosine triphosphate at 1373cm Figure 15 . It can be clearly seen from Figures 13-15 that the fingerprint peak of ATP. Further, the SERS spectrum of ATP molecules in urine from high concentration (1x10 -2 mol / L) to low concentration 1x10 -7 mol / L is presented. It is found that the characteristic peak intensity at 1373cm -1 also decreases as the concentration gradually decreases, and when the ATP concentration decreases to 1x10 -7 mol / L, the characteristic peak can still be detected. This result shows that the use of Au@ZIF-8 substrate on the Raman spectrometer for the detection of ATP in urine can obtain ideal detection effect. The SERS intensity at 1373cm -1 gradually increases, and the SERS peak intensity at 1373cm -1 is related to the concentration of adenosine triphosphate, and it is found that they present a good linear relationship Figure 16 , the linear regression equation is y=36.288x-37.677, and the correlation coefficient R 2 is 0.999.

[0072] The Au@ZIF-8 SERS substrate is successfully prepared, and its good performance in ATP detection is verified. When the ATP molecule contacts with Au@ZIF-8, the phosphate group in ATP will coordinate with Zn 2+ in ZIF-8, thereby shortening the distance between ATP molecules and AuNPs, and enhancing the SERS signal. The obtained signal is processed, and the linear regression equation is y=36.288x-37.677 (R 2 =0.999).

[0073] ATP standard solution and ATP in urine are detected, and malachite green (MG) is used as a probe molecule, and the RSD is calculated to be 11.43%, which proves that the Au@ZIF-8 SERS substrate has good sensitivity and reproducibility. For ATP standard solution, the detection limit reaches 10-7 mol / L, which shows that the SERS technology combined with the Au@ZIF-8 substrate has a very high sensitivity for the detection of ATP. For ATP in urine, the detection limit is 10 -5 mol / L, which proves the effectiveness of this method in actual sample detection.

[0074] 6. The silver nanoparticles obtained in Comparative Example 1 were used as SERS active substrates to detect ATP in the same urine sample as in Example 1. The specific detection method, steps, and parameters were the same as in Example 1. The spectrum of the ATP detection in the urine sample by the SERS active substrate of AuNPs@ZIF-8 in Example 1 is shown in FIG. Figure 17 , AgATP 10 in Comparative Example 1 - 7 mol / L and AuNPs@ZIF-8ATP10 in Example 1 -7 mol / L SERS enhancement effect comparison chart as shown Figure 19 shown.

[0075] Depend on Figure 19 It can be seen that 1380cm -1 A concentration of 10 -7 The characteristic peak intensity of ATP at 1380 cm-1 of Example 1 is only about 90, while the characteristic peak intensity of ATP at 1380 cm-1 in Example 1 is about 1000. This shows that the AuNPs@ZIF-8 SERS substrate used in Example 1 has better SERS performance than the silver nanoparticle-based SERS substrate in Comparative Example 1.

[0076] 7. The Ag@ZIF-8 obtained in Comparative Example 2 was used as the SERS active substrate to detect ATP in the urine sample same as in Example 1. The specific detection method, steps, and parameters were the same as in Example 1. The spectrum of the Ag@ZIF-8 SERS active substrate detecting ATP in the urine sample is shown in FIG. Figure 18 , Ag@ZIF-8ATP 10 -7 mol / L and AuNPs@ZIF-8ATP10 -7 mol / L SERS enhancement effect comparison chart as shown Figure 20 shown.

[0077] Depend on Figure 20 It can be seen that the concentration of 10 -7The characteristic peak of ATP in Example 1 is about 1000 intensity at 1380 cm-1, while the characteristic peak of ATP in Comparative Example 2 is only about 233 intensity. It is shown that the AuNPs@ZIF-8 used in Example 1 has better SERS substrate enhancement performance than the Ag@ZIF-8 substrate in Comparative Example 2.

[0078] The above only describes the preferred embodiments of the present application, and it should be noted that those skilled in the art can make several improvements and refinements without departing from the principles of the present application, and these improvements and refinements should also be considered within the scope of protection of the present application.

Claims

1. A method for preparing a SERS substrate based on MOF material, characterized in that: The following steps are involved: (1) Synthesis of ZIF-8: Prepare a methanol solution of zinc nitrate hexahydrate and a methanol solution of 2-methylimidazole respectively; mix the two solutions and let them stand to produce a white precipitate; The white precipitate was collected, dissolved in methanol by ultrasonication, centrifuged, and then washed alternately with methanol and distilled water 3 to 4 times and dried to obtain the MOF material of ZIF-8; (2) Synthesis of AuNPs: Heat the chloroauric acid solution to a boil, quickly add the trisodium citrate solution, stop heating after 10-12 minutes, continue stirring the solution to room temperature, and refrigerate at 4-10°C to obtain the AuNPs solution; (3) Preparation of AuNPs@ZIF-8 particles: The ZIF-8 MOF material prepared in step (1) was dissolved in the AuNPs solution prepared in step (2) and stirred, and then the mixed solution was collected by centrifugation. This was repeated 2 to 3 times to obtain AuNPs@ZIF-8 particle sol; (4) Preparation of SERS substrate: The AuNPs@ZIF-8 sol was added to ultrapure water and dissolved by ultrasonication to serve as the substrate; The concentration of zinc nitrate hexahydrate in the methanol solution of zinc nitrate hexahydrate in step (1) is 0.08-0.1 g / mL; the concentration of 2-methylimidazole in the methanol solution of 2-methylimidazole is 0.06-0.07 g / mL; The volume ratio of the methanol solution of zinc nitrate hexahydrate to the methanol solution of 2-methylimidazole in step (1) is 15-25:55-65; The mixing in step (1) is carried out by ultrasonic mixing for 1 to 1.25 hours; the standing time is 18 to 24 hours; The centrifugal speed in step (1) is 10,000 rpm, and the centrifugation time is 5 to 8 minutes; The mass concentration of the chloroauric acid solution in step (2) is 0.01-0.02%; the mass concentration of the trisodium citrate solution is 1-1.5%; the volume ratio of the chloroauric acid solution to the trisodium citrate solution is 100:1-3; The heating temperature in step (2) is 110-120° C.; the stirring speed before heating and boiling is 100-150 rpm, and the stirring speed after heating and boiling is 500-600 rpm, and trisodium citrate solution is added simultaneously and rapidly; The mass volume ratio of the ZIF-8 MOF material to the AuNPs solution in step (3) is 13-15 mg:10 mL; The stirring time in step (3) is 10-12 hours; the centrifugal speed is 5000-5500 rpm.

2. The SERS substrate material based on MOF material prepared by the preparation method according to claim 1, characterized in that: The SERS substrate based on MOF material is used for adenosine triphosphate detection.

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