A fluorescent probe for detecting Mucin1 tumor marker and preparation method thereof

Abstract

The present invention belongs to the technical field of fluorescent probes, and specifically provides a fluorescent probe for detecting a Mucin1 tumor marker and a preparation method thereof, wherein the fluorescent probe comprises the following components in parts by weight: 6 to 10 parts of silver nanoclusters functionalized with a Mucin1 aptamer, 4 to 6 parts of Tb-MOFs, 4 to 6 parts of NH4Ac-HAc buffer, 2 to 3 parts of polyethyleneimine, and 40 to 60 parts of distilled water. The Mucin1 aptamer is modified on the surface of the silver nanoclusters and combined with Tb-MOFs, and fluorescence resonance energy transfer occurs, the characteristic green fluorescence of Tb is quenched, and the fluorescent probe emits the red fluorescence of the silver nanoclusters; when a target is added, the target is combined with the silver nanoclusters functionalized with the Mucin1 aptamer, the red fluorescence is quenched, and the characteristic green fluorescence of Tb is restored. The fluorescent probe has the advantages of simple operation, visualization, and high sensitivity.

Description

Technical Field

[0001] The present invention relates to the technical field of fluorescent probes, and in particular to a fluorescent probe for detecting a Mucin1 tumor marker and a preparation method thereof. Background Art

[0002] Mucin1 is a glycoprotein. Studies have shown that Mucin1 is overexpressed in a variety of adenocarcinomas and is closely related to the infiltration, malignancy, and metastasis of cancer. At the same time, Mucin1 is also a target for anticancer therapy. Therefore, high-sensitivity detection of Mucin1 is crucial for early diagnosis of malignant tumors and targeted therapy.

[0003] The current methods for detecting Mucin1 include ELISA, electrochemiluminescence, high performance liquid chromatography, and ICP-MS. Each has its own advantages, but also has limitations. For example, the HPLC instrument is expensive and time-consuming; the ELISA method is easily affected by environmental factors. Therefore, it is imperative to establish a new method for detecting Mucin1. In recent years, biosensor technology based on nucleic acid aptamers has developed rapidly and has been used to detect bacteria, cells and other fields. The analytical method constructed by combining nucleic acid aptamers with fluorescent probes to detect proteins has the advantages of good specificity and no labeling, but the sensitivity is not high enough, the pre-treatment is complicated, and the background interference is large. Summary of the invention

[0004] In view of the above situation, in order to overcome the defects of the prior art, the present invention provides a fluorescent probe for detecting the Mucin1 tumor marker and a preparation method thereof, wherein the silver nanoclusters functionalized by the Mucin1 aptamer are combined with Tb-MOFs, and fluorescence resonance energy transfer occurs between Tb-MOFs and the silver nanoclusters functionalized by the Mucin1 aptamer, the green fluorescence of the Tb-MOFs is absorbed by the silver nanoclusters, and the fluorescent probe emits the red fluorescence of the silver nanoclusters; when Mucin1 is added, Mucin1 is combined with the silver nanoclusters functionalized by the Mucin1 aptamer, the red fluorescence is quenched, and the green fluorescence of the Tb-MOFs is enhanced. The fluorescent probe has the advantages of simple operation, visualization, and high sensitivity.

[0005] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present invention is as follows: The present invention proposes a fluorescent probe for detecting the Mucin1 tumor marker, wherein the fluorescent probe comprises the following components in parts by weight: 6 to 10 parts of silver nanoclusters functionalized with Mucin1 aptamers, 4 to 6 parts of Tb-MOFs, 4 to 6 parts of NH4Ac-HAc buffer, 2 to 3 parts of polyethyleneimine, and 40 to 60 parts of distilled water.

[0006] Preferably, the method for preparing the Mucin1 aptamer-functionalized silver nanoclusters comprises the following steps:

[0007] S1. Add 0.6-1.0 mL of NH4Ac–HAc buffer, 300-500 µL of 100 μmol / L Mucin1 aptamer solution, 1.5-2 mL of distilled water, and 200-300 µL of 1 mmol / L AgNO3 to a 4 mL EP tube, mix well, and place on ice for 30 minutes to obtain a mixed reaction solution.

[0008] S2, take 100-150 μL of a newly prepared 1 mmol / L NaBH4 solution, quickly add it to the mixed reaction solution prepared in step S1, and shake it vigorously for 30 seconds to reduce the silver ions to obtain a reduction reaction solution;

[0009] S3. The reduction reaction solution prepared in step S2 is placed in a dark environment and allowed to react at 4° C. for 72 h to obtain silver nanoclusters functionalized with the Mucin1 aptamer.

[0010] Preferably, the base sequence of the Mucin1 adaptor in step S1 is TCC GAG TTT CCC TGC CCCAAC CTC CAC CTG GGG TCA ATAA.

[0011] Preferably, the pH of the NH4Ac-HAc buffer is 6.8 and the concentration is 0.2 mol / L.

[0012] Preferably, the method for preparing Tb-MOFs comprises the following steps:

[0013] ① Weigh 0.4-0.6 mmol Tb(NO3)3·6H2O and dissolve it in 15 mL of mixed solvent, add 0.4-0.6 mmol trimesic acid and 0.2-0.4 mmol o-phenanthroline, dissolve and mix evenly to obtain a reaction solution;

[0014] ② Add 40-60 µL of triethylamine to the reaction solution prepared in step ①, mix well and transfer to a 25 mL polytetrafluoroethylene-lined reactor, place it in an oven and heat it at 140 °C for 24 h. After cooling to room temperature, centrifuge at 8000 rpm to obtain a precipitate, wash it three times with distilled water, and place it in an oven and dry it at 60 °C for 12 h to obtain Tb-MOFs.

[0015] Preferably, in step ①, the mixed solvent consists of DMF and water in a mass ratio of 1 to 2:1.

[0016] Preferably, the polyethyleneimine is a hyperbranched polyethyleneimine with a molecular weight of 1200-5000 Da.

[0017] The present invention also provides a method for preparing a fluorescent probe for detecting the Mucin1 tumor marker, comprising the following steps:

[0018] i. In a 2 mL EP tube, add NH4Ac-HAc buffer and silver nanoclusters functionalized with Mucin1 aptamer by mass, mix well and add Tb-MOFs, then place the EP tube in a microplate incubator and incubate at 60°C for 2 h;

[0019] ii. Add polyethyleneimine and distilled water to the EP tube described in step i according to mass proportions, continue incubating at 60° C. for 2 to 4 hours, and mix well to obtain a fluorescent probe for detecting the Mucin1 tumor marker.

[0020] The beneficial effects achieved by the present invention are as follows:

[0021] The invention modifies the surface of silver nanoclusters with Mucin1 aptamers, provides specific recognition capability for the silver nanoclusters, adjusts the fluorescence absorption and fluorescence emission of the silver nanoclusters, and enhances the stability of the silver nanoclusters; the addition of o-phenanthroline in the synthesis of Tb-MOFs fluorescent materials can effectively enhance the intrinsic green fluorescence emission of rare earth ion Tb, and the addition of deprotonating agent triethylamine can improve the synthesis speed and yield of MOFs materials; when the silver nanoclusters functionalized with Mucin1 aptamers are mixed with Tb-MOFs, the two are in close contact, and fluorescence resonance energy transfer occurs. Under the excitation of 100 nm wavelength, the green fluorescence of Tb in Tb-MOFs disappears, and the energy is transferred to the silver nanoclusters, and the red fluorescence of the silver nanoclusters is enhanced; when the target Mucin1 is added, Mucin1 combines with the silver nanoclusters functionalized with the Mucin1 aptamer, and its red fluorescence is weakened, and the green fluorescence of Tb-MOFs is restored, with ratio fluorescence change, and through the change of the fluorescence signal, the intuitive visual detection of Mucin1 can be realized, which is convenient for rapid understanding and analysis of the results, and the addition of polyethyleneimine can make the probe more stable and the reaction more sensitive. The preparation process of the fluorescent probe of the present invention is simple and direct, does not require complex chemical modification or long pre-treatment steps, and the required reagent cost is not high. The fluorescent probe provides the possibility of low-cost Mucin1 detection, which is particularly suitable for experimental conditions with limited resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only for the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] FIG1 is a scanning electron micrograph of the silver nanoclusters functionalized with the Mucin1 aptamer prepared in Example 1 of the present invention;

[0024] FIG2 is a scanning electron microscope image of Tb-MOFs prepared in Example 1 of the present invention;

[0025] FIG3 is a fluorescence curve of different concentrations of Mucin1 detection solution;

[0026] FIG4 is a regression equation fitting curve of different concentrations of Mucin1 detection solution;

[0027] FIG. 5 is a fluorescence curve of the detection solution in different embodiments. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0029] Unless otherwise defined, all professional and scientific terms used herein have the same meanings as those familiar to those skilled in the art. In addition, any methods and materials similar or equivalent to those described herein may be applied to the present invention. The preferred implementation methods and materials described herein are for demonstration purposes only and are not intended to limit the content of this application.

[0030] Example 1: This example proposes a fluorescent probe for detecting the Mucin1 tumor marker, the fluorescent probe comprising the following components in parts by weight: 6 parts of silver nanoclusters functionalized with Mucin1 aptamers, 6 parts of Tb-MOFs, 4 parts of NH4Ac-HAc buffer, 2 parts of polyethyleneimine, and 40 parts of distilled water.

[0031] The method for preparing the Mucin1 aptamer-functionalized silver nanoclusters comprises the following steps:

[0032] S1. Add 0.6 mL of 0.2 mol / L NH4Ac–HAc buffer (pH 6.8), 300 µL of 100 μmol / L Mucin1 aptamer solution, 1.5 mL of distilled water, and 200 µL of 1 mmol / L AgNO3 into a 4 mL EP tube, mix well, and place on ice for 30 minutes to obtain a mixed reaction solution.

[0033] S2, take 100 μL of the newly prepared 1 mmol / L NaBH4 solution, quickly add it to the mixed reaction solution prepared in step S1, and shake it vigorously for 30 seconds to reduce the silver ions to obtain a reduction reaction solution;

[0034] S3. The reduction reaction solution prepared in step S2 is placed in a dark environment and allowed to react at 4° C. for 72 h to obtain silver nanoclusters functionalized with the Mucin1 aptamer.

[0035] The base sequence of the Mucin1 adaptor in step S1 is TCC GAG TTT CCC TGC CCC AAC CTCCAC CTG GGG TCA ATAA.

[0036] The preparation method of Tb-MOFs comprises the following steps:

[0037] ① Weigh 0.4 mmol Tb(NO3)3·6H2O and dissolve it in 15 mL of a mixed solvent consisting of DMF and water in a mass ratio of 1:1, add 0.4 mmol trimesic acid and 0.2 mmol o-phenanthroline, dissolve and mix evenly to obtain a reaction solution;

[0038] ② Add 40 µL of triethylamine to the reaction solution prepared in step ①, mix well and transfer to a 25 mL polytetrafluoroethylene-lined reactor, place it in an oven and heat it at 140 °C for 24 h. After cooling to room temperature, centrifuge at 8000 rpm to obtain a precipitate, wash it three times with distilled water, and place it in an oven and dry it at 60 °C for 12 h to obtain Tb-MOFs.

[0039] The polyethyleneimine is a hyperbranched polyethyleneimine with a molecular weight of 1200 Da.

[0040] This embodiment also proposes a method for preparing a fluorescent probe for detecting the Mucin1 tumor marker, comprising the following steps:

[0041] i. In a 2 mL EP tube, add NH4Ac-HAc buffer and silver nanoclusters functionalized with Mucin1 aptamer by mass, mix well and add Tb-MOFs, then place the EP tube in a microplate incubator and incubate at 60°C for 2 h;

[0042] ii. Add polyethyleneimine and distilled water to the EP tube in step i according to mass proportions, continue incubating at 60° C. for 2 h, and mix well to obtain a fluorescent probe for detecting the Mucin1 tumor marker.

[0043] Example 2: The present invention proposes a fluorescent probe for detecting the Mucin1 tumor marker, wherein the fluorescent probe comprises the following components in parts by weight: 10 parts of silver nanoclusters functionalized with Mucin1 aptamers, 4 parts of Tb-MOFs, 6 parts of NH4Ac-HAc buffer, 3 parts of polyethyleneimine, and 60 parts of distilled water.

[0044] The method for preparing the Mucin1 aptamer-functionalized silver nanoclusters comprises the following steps:

[0045] S1. Add 1.0 mL of 0.2 mol / L NH4Ac–HAc buffer (pH 6.8), 500 µL of 100 μmol / L Mucin1 aptamer solution, 2 mL of distilled water, and 300 µL of 1 mmol / L AgNO3 into a 4 mL EP tube, mix well, and place on ice for 30 minutes to obtain a mixed reaction solution.

[0046] S2, take 150 μL of the newly prepared 1 mmol / L NaBH4 solution, quickly add it to the mixed reaction solution prepared in step S1, and shake it vigorously for 30 seconds to reduce the silver ions to obtain a reduction reaction solution;

[0047] S3. The reduction reaction solution prepared in step S2 is placed in a dark environment and allowed to react at 4° C. for 72 h to obtain silver nanoclusters functionalized with the Mucin1 aptamer.

[0048] The base sequence of the Mucin1 adaptor in step S1 is TCC GAG TTT CCC TGC CCC AAC CTCCAC CTG GGG TCA ATAA.

[0049] The preparation method of Tb-MOFs comprises the following steps:

[0050] ① Weigh 0.6 mmol Tb(NO3)3·6H2O and dissolve it in 15 mL of a mixed solvent consisting of DMF and water in a mass ratio of 2:1, add 0.6 mmol trimesic acid and 0.4 mmol o-phenanthroline, dissolve and mix evenly to obtain a reaction solution;

[0051] ② Add 60 µL of triethylamine to the reaction solution prepared in step ①, mix well and transfer to a 25 mL reactor with a polytetrafluoroethylene liner, place it in an oven and heat it at 140 ° C for 24 h. After cooling to room temperature, centrifuge at 8000 rpm to obtain a precipitate, wash it three times with distilled water, and place it in an oven at 60 ° C for 12 h to obtain Tb-MOFs.

[0052] The polyethyleneimine is a hyperbranched polyethyleneimine with a molecular weight of 5000 Da.

[0053] The present invention also provides a method for preparing a fluorescent probe for detecting the Mucin1 tumor marker, comprising the following steps:

[0054] i. In a 2 mL EP tube, add NH4Ac-HAc buffer and silver nanoclusters functionalized with Mucin1 aptamer by mass, mix well and add Tb-MOFs, then place the EP tube in a microplate incubator and incubate at 60°C for 2 h;

[0055] ii. Add polyethyleneimine and distilled water to the EP tube in step i according to mass proportions, continue incubating at 60° C. for 4 h, and mix well to obtain a fluorescent probe for detecting the Mucin1 tumor marker.

[0056] Experimental Example 3: The present invention proposes a fluorescent probe for detecting the Mucin1 tumor marker, wherein the fluorescent probe comprises the following components in parts by weight: 8 parts of silver nanoclusters functionalized with Mucin1 aptamers, 5 parts of Tb-MOFs, 5 parts of NH4Ac-HAc buffer, 2.5 parts of polyethyleneimine, and 50 parts of distilled water.

[0057] The method for preparing the Mucin1 aptamer-functionalized silver nanoclusters comprises the following steps:

[0058] S1. Add 0.8 mL of 0.2 mol / L NH4Ac–HAc buffer (pH 6.8), 400 µL of 100 μmol / L Mucin1 aptamer solution, 1.8 mL of distilled water, and 250 µL of 1 mmol / L AgNO3 into a 4 mL EP tube, mix well, and place on ice for 30 minutes to obtain a mixed reaction solution.

[0059] S2, take 130 μL of the newly prepared 1 mmol / L NaBH4 solution, quickly add it to the mixed reaction solution prepared in step S1, and shake it vigorously for 30 seconds to reduce the silver ions to obtain a reduction reaction solution;

[0060] S3. The reduction reaction solution prepared in step S2 is placed in a dark environment and allowed to react at 4° C. for 72 h to obtain silver nanoclusters functionalized with the Mucin1 aptamer.

[0061] The base sequence of the Mucin1 adaptor in step S1 is TCC GAG TTT CCC TGC CCC AAC CTCCAC CTG GGG TCA ATAA.

[0062] The preparation method of Tb-MOFs comprises the following steps:

[0063] ① Weigh 0.5 mmol Tb(NO3)3·6H2O and dissolve it in 15 mL of a mixed solvent consisting of DMF and water in a mass ratio of 1.5:1, add 0.5 mmol trimesic acid and 0.3 mmol o-phenanthroline, dissolve and mix evenly to obtain a reaction solution;

[0064] ② Add 50 µL of triethylamine to the reaction solution prepared in step ①, mix well and transfer to a 25 mL polytetrafluoroethylene-lined reactor, place it in an oven and heat it at 140 °C for 24 h. After cooling to room temperature, centrifuge at 8000 rpm to obtain a precipitate, wash it three times with distilled water, and place it in an oven and dry it at 60 °C for 12 h to obtain Tb-MOFs.

[0065] The polyethyleneimine is a hyperbranched polyethyleneimine with a molecular weight of 3000 Da.

[0066] This embodiment also proposes a method for preparing a fluorescent probe for detecting the Mucin1 tumor marker, comprising the following steps:

[0067] i. In a 2 mL EP tube, add NH4Ac-HAc buffer and silver nanoclusters functionalized with Mucin1 aptamer by mass, mix well and add Tb-MOFs, then place the EP tube in a microplate incubator and incubate at 60°C for 2 h;

[0068] ii. Add polyethyleneimine and distilled water to the EP tube in step i according to mass proportions, continue incubating at 60° C. for 3 h, and mix well to obtain a fluorescent probe for detecting the Mucin1 tumor marker.

[0069] Comparative Example 1: This comparative example proposes a fluorescent probe for detecting the Mucin1 tumor marker. The only difference between the comparative example and Example 1 is that Tb-MOFs is not added, and the other components, component contents, and experimental steps are the same as those in Example 1.

[0070] Comparative Example 2: This comparative example proposes a fluorescent probe, which differs from Example 1 only in that the silver nanoclusters functionalized with the Mucin1 aptamer are not added, and the remaining components, component contents, and experimental steps are the same as those in Example 1.

[0071] Experimental Example 1: The microscopic morphology of the silver nanoclusters functionalized with the Mucin1 aptamer synthesized in Example 1 was observed using a projection electron microscope, and the microscopic morphology of the Tb-MOFs synthesized in Example 1 was observed using a scanning electron microscope.

[0072] FIG1 is a scanning electron microscope image of the silver nanoclusters functionalized with the Mucin1 aptamer prepared in Example 1 of the present invention. As shown in the figure, the silver nanoclusters functionalized with the Mucin1 aptamer are evenly distributed, with a diameter of about 2 nm and a small particle size. FIG2 is a scanning electron microscope image of the Tb-MOFs prepared in Example 1 of the present invention. As shown in the figure, the particle size of the Tb-MOFs is large and is in the shape of nanorods. The above shows the successful preparation of the silver nanoclusters functionalized with the Mucin1 aptamer and Tb-MOFs proposed in the present invention.

[0073] Experimental Example 2: Fluorescence titration experiment:

[0074] In a 2 mL EP tube, 40 µL of NH4Ac-HAc buffer solution with a pH of 6.5 and 50 µL of the fluorescent probe prepared in Example 1 were added, and then different volumes of 100 μM Mucin1 solution were added to the EP tube, and the volume was adjusted to 2 mL with distilled water to obtain detection solutions with Mucin1 concentrations of 0 nM, 0.5 μM, 1.0 μM, 2.0 μM, 5.0 μM, 10 μM, 20 μM, 30 μM, and 50 μM, respectively. The reaction was allowed to proceed for 30 min; a wavelength range of 400-700 nm was scanned on a Hitachf-7000 fluorescence spectrophotometer, and the excitation wavelength Ex=330 nm, the excitation slit 5 nm and the emission slit 10 nm were set, the maximum emission wavelength Em=546 nm of Tb-MOFs, and the maximum emission wavelength Em=621 nm of the silver nanoclusters functionalized with the Mucin1 aptamer, and the fluorescence curves of the detection solutions corresponding to different Mucin1 concentrations were recorded.

[0075] Figure 3 shows the fluorescence curves of different concentrations of Mucin1 detection solution. As shown in the figure, when Mucin1 is not added, the red fluorescence of the detection solution at 621 nm is stronger and the green fluorescence at 546 nm is weaker. As the concentration of Mucin1 gradually increases, the red fluorescence gradually weakens and the green fluorescence gradually increases, showing a visualized fluorescence color change. This is because when the target Mucin1 is added, Mucin1 combines with the silver nanoclusters functionalized with the Mucin1 aptamer, which weakens the binding of the silver nanoclusters to Tb-MOFs. The silver nanoclusters reduce energy input, the red fluorescence weakens, and the green fluorescence of Tb-MOFs recovers, showing a ratio fluorescence change.

[0076] Experimental Example 3: Numerical fitting of ratio fluorescence values:

[0077] Record the fluorescence intensity values ​​at 546 nm and 621 nm corresponding to different concentrations in Experiment 2, and denote them as F 546 and F 621 , fit the regression equation: F 546 / F 621=k [Mucin1 concentration] + b, where k is the slope and b is the intercept. The detection limit LOD is further calculated as LOD = 3σ / k, where σ is the standard deviation of the blank sample measurement value.

[0078] FIG4 is a regression equation fitting curve of different concentrations of Mucin1 detection solution. As shown in the figure, F 546 / F 621 =0.07135[Mucin1 concentration]+0.09019, R 2 =0.98986, with a good fitting relationship in the Mucin1 concentration range of 0.5~10 μM, and the detection limit LOD was calculated to be 68 nM, indicating that the fluorescent probe proposed in the present invention can detect Mucin1 ratiometrically and has excellent sensitivity and detection limit.

[0079] Experimental Example 4: In 4 2 mL EP tubes, 40 µL of NH4Ac-HAc buffer solution with a pH of 6.5 was added, and 50 µL of the fluorescent probes prepared in Examples 2-3 and Comparative Examples 1-2 were added respectively, and the volume was adjusted to 2 mL with distilled water, and the reaction was allowed to proceed for 30 min; a Hitachf-7000 fluorescence spectrophotometer was used to scan in the wavelength range of 400-700 nm, and the excitation wavelength Ex=330 nm, the excitation slit 5 nm, and the emission slit 10 nm were set, and the fluorescence curves of different detection solutions were recorded.

[0080] Figure 5 is the fluorescence curves of the detection liquid in different embodiments. As shown in the figure, the fluorescence curves of Examples 2-3 are similar to those of Example 1, with stronger red fluorescence and weaker green fluorescence. The fluorescent probe prepared in Comparative Example 1 does not contain Tb-MOFs, and the silver nanoclusters functionalized with the Mucin1 aptamer have no energy source and therefore have no fluorescence; while the fluorescent substance of the fluorescent probe prepared in Comparative Example 2 is composed only of Tb-MOFs, and therefore only exhibits the characteristic emission of the rare earth ion Tb; therefore, the fluorescent probes prepared in Comparative Examples 1 and 2 are not suitable for fluorescence detection of Mucin1.

[0081] The present invention and its implementation methods are described above, and such description is not restrictive, and the actual application is not limited thereto. In short, if ordinary technicians in the field are inspired by it, without departing from the purpose of the invention, they can design methods and embodiments similar to the technical solution without creativity, which should all fall within the protection scope of the present invention.

Claims

1. A fluorescent probe for detecting Mucin1 tumor marker, characterized in that: The fluorescent probe comprises the following components in parts by weight: 6-10 parts of silver nanoclusters functionalized with Mucin1 aptamers, 4-6 parts of Tb-MOFs, 4-6 parts of NH4Ac-HAc buffer, 2-3 parts of polyethyleneimine, and 40-60 parts of distilled water; The method for preparing the Mucin1 aptamer-functionalized silver nanoclusters comprises the following steps: S1. Add 0.6-1.0 mL of NH4Ac-HAc buffer, 300-500 µL of 100 μmol / L Mucin1 aptamer solution, 1.5-2 mL of distilled water, and 200-300 µL of 1 mmol / L AgNO3 to a 4 mL EP tube, mix well, and place on ice for 30 minutes to obtain a mixed reaction solution. S2, take 100-150 μL of a newly prepared 1 mmol / L NaBH4 solution, quickly add it to the mixed reaction solution prepared in step S1, and shake it vigorously for 30 seconds to reduce the silver ions to obtain a reduction reaction solution; S3, placing the reduction reaction solution prepared in step S2 in a dark environment, and allowing it to react at 4°C for 72 h to obtain silver nanoclusters functionalized with the Mucin1 aptamer; The base sequence of the Mucin1 aptamer in step S1 is TCC GAG TTT CCC TGC CCC AAC CTC CACCTG GGG TCA ATAA; The preparation method of Tb-MOFs comprises the following steps: ① Weigh 0.4-0.6 mmol Tb(NO3)3·6H2O and dissolve it in 15 mL of mixed solvent, add 0.4-0.6 mmol trimesic acid and 0.2-0.4 mmol o-phenanthroline, dissolve and mix evenly to obtain a reaction solution; ② Add 40-60 µL of triethylamine to the reaction solution prepared in step ①, mix well and transfer to a 25 mL polytetrafluoroethylene-lined reactor, place it in an oven and heat it at 140 ° C for 24 h. After cooling to room temperature, centrifuge at 8000 rpm to obtain a precipitate, wash it three times with distilled water, and place it in an oven at 60 ° C for 12 h to obtain Tb-MOFs.

2. A fluorescent probe for detecting Mucin1 tumor marker according to claim 1, characterized in that: The pH of the NH4Ac–HAc buffer is 6.8 and the concentration is 0.2 mol / L.

3. A fluorescent probe for detecting Mucin1 tumor marker according to claim 2, characterized in that: In the step ①, the mixed solvent consists of DMF and water in a mass ratio of 1-2:

1.

4. A fluorescent probe for detecting Mucin1 tumor marker according to claim 3, characterized in that: The polyethyleneimine is a hyperbranched polyethyleneimine with a molecular weight of 1200-5000 Da.

5. A method for preparing a fluorescent probe for detecting a Mucin1 tumor marker according to any one of claims 1 to 4, characterized in that: The following steps are involved: i. In a 2 mL EP tube, add NH4Ac-HAc buffer and silver nanoclusters functionalized with Mucin1 aptamer by mass, mix well and add Tb-MOFs, then place the EP tube in a microplate incubator and incubate at 60°C for 2 h; ii. Add polyethyleneimine and distilled water to the EP tube described in step i according to mass proportions, continue incubating at 60° C. for 2 to 4 h, and mix well to obtain a fluorescent probe for detecting the Mucin1 tumor marker.

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