Aggregation-induced emission fluorescent probe for detecting cuprous ion Cu (I) as well as preparation method and application of aggregation-induced emission fluorescent probe

Abstract

The invention discloses an aggregation-induced emission fluorescent probe for detecting cuprous ions Cu (I) as well as a preparation method and application of the aggregation-induced emission fluorescent probe. The structure of the aggregation-induced emission fluorescent probe is shown as a formula I; wherein R is selected from one of H, alkyl with the carbon atom number of C1 to C4 and COOH. The fluorescent probe provided by the invention takes a chromophore quinoline nitrile derivative as an AIE structural unit and thioether-rich bis (2-((2-(ethyl sulfide) ethyl)-sulfo) ethyl) amine as a Cu (I) recognition unit, has excellent aggregation-induced emission characteristics, shows excellent selectivity and high-sensitivity response to Cu (I), and can be used for detecting Cu (I). In addition, the process of reducing Cu (II) into Cu (I) can be detected in situ, and technical support is provided for revealing the effect of Cu ions in the physiological and pathological processes of cells in the future. # imgabs0 #

Description

Technical Field

[0001] The present invention relates to the field of fluorescent probe preparation, and more specifically, to an aggregation-induced luminescence fluorescent probe for detecting cuprous ions Cu(I), and a preparation method and application thereof. Background Art

[0002] As an indispensable coenzyme factor for a variety of enzymes and proteins, copper ions play a vital role in the field of biochemistry. They mediate multiple activities such as redox reactions in the cellular respiratory chain, defense mechanisms against oxidative stress, and neuronal functions. When copper ions are out of balance, they may be closely related to a variety of pathological conditions, including but not limited to Wilson's disease, neurodegenerative diseases (such as Parkinson's disease, Alzheimer's disease), and atherosclerosis. In the reducing environment of cells, copper ions usually exist in the form of monovalent cations Cu(I). Free Cu(I) is considered to be more biotoxic than divalent cations Cu(II) in vivo. Therefore, real-time monitoring of the dynamic changes of intracellular Cu(I) is crucial to revealing its role in cellular physiological and pathological processes.

[0003] In biological imaging and molecular probe technology, fluorescent probes have become ideal tools for studying the dynamic changes and subcellular distribution of Cu(Ⅰ) in vivo due to their high sensitivity, high selectivity and real-time monitoring capabilities. However, traditional fluorescent probes often suffer from photobleaching and are prone to severe aggregation quenching (ACQ), resulting in poor photostability and "false positive" reactions (Yanting L, Xiaoyan C, Qi W, et al. Advanced Functional Materials, 2021, 32(6)). The new AIE (Aggregation-Induced Emission) type fluorescent probe overcomes the limitations of traditional organic fluorescent probes in concentration quenching due to its "aggregation-enhanced luminescence" characteristics, and AIE type fluorescent probes are more resistant to photobleaching, so they have superior photostability and higher signal reliability. In addition, AIE type fluorescent probes have excellent biocompatibility and low cytotoxicity, which makes them show great application potential and significant technical advantages in the field of biological imaging and detection. However, there are relatively few aggregation-induced emission fluorescent probes used to detect Cu(Ⅰ). Therefore, constructing Cu(I) fluorescent probes with AIE properties is of great significance for the detection of Cu(I) in organisms and cells. Summary of the invention

[0004] The first object of the present invention is to provide an aggregation-induced emission fluorescent probe for detecting cuprous ions Cu(I). The fluorescent probe prepared by the present invention has aggregation-induced emission (AIE) characteristics, has good response and excellent selectivity to Cu(I), and the fluorescent probe can sensitively detect the process of reduction of Cu(II) to Cu(I) in situ, providing technical support for revealing the role of Cu ions in cell physiology and pathology in the future.

[0005] The second object of the present invention is to provide a method for preparing the aggregation-induced emission fluorescent probe as described above.

[0006] The third object of the present invention is to provide an application of the aggregation-induced emission fluorescent probe as described above in the preparation of a product for detecting cuprous ions Cu(I).

[0007] The fourth object of the present invention is to provide a method for detecting cuprous ions Cu(I) based on the aggregation-induced emission fluorescent probe as described above.

[0008] In order to achieve the first objective, the present invention discloses an aggregation-induced luminescence fluorescent probe for detecting cuprous ions Cu(I), wherein the structure of the aggregation-induced luminescence fluorescent probe is shown in the following formula I;

[0009]

[0010] Wherein, R is selected from one of H, an alkyl group with carbon atoms ranging from C1 to C4, and COOH.

[0011] By screening a large number of Cu(Ⅰ) recognition units and AIE structural units, the present invention constructs a fluorescent probe with AIE effect for detecting Cu(Ⅰ), which uses sulfide-rich bis(2-((2-(ethylsulfide)ethyl)-thio)ethyl)amine (NS4) as a Cu(Ⅰ) recognition unit and a chromophore quinolinenitrile derivative as an AIE structural unit. In the fluorescent probe, Cu(Ⅰ) can be combined with the fluorescent probe through coordination with NS4 to change the fluorescent signal. Therefore, the fluorescent probe provided by the present invention has good response and excellent selectivity to Cu(Ⅰ), and the fluorescent probe can sensitively detect the process of reduction of Cu(Ⅱ) to Cu(Ⅰ) in situ.

[0012] Further, the R is selected from methyl (named QM-NS4) or COOH (named QMCOOH-NS4).

[0013] In order to achieve the second objective, the present invention discloses a method for preparing the aggregation-induced emission fluorescent probe as described above, comprising the following steps:

[0014]

[0015] (1) dissolving sodium ethoxide, 4-[bis-(2-chloroethyl)amino]benzaldehyde and 2-(ethylthio)ethanethiol in anhydrous ethanol, and reacting under reflux in an inert atmosphere. After the reaction, deionized water is added to the system, and the mixture is extracted with dichloromethane. The organic phase is washed with deionized water and saturated brine in sequence, dried over anhydrous sodium sulfate, concentrated, and separated and purified by column chromatography to obtain compound 1;

[0016] (2) Compound 1, Compound 2 and a catalyst are added to a solvent, and refluxed under a nitrogen atmosphere for reaction. After the reaction is completed, the mixture is concentrated, separated and purified by column chromatography to obtain the product.

[0017] Furthermore, in step (1), the molar ratio of sodium ethoxide, 2-(ethylthio)ethanethiol, and 4-[bis-(2-chloroethyl)amino]benzaldehyde is 3:2:0.5-1.

[0018] Furthermore, the molar volume ratio of sodium ethoxide to ethanol in step (1) is 1 mmol:(1.5-2) mL.

[0019] Furthermore, the reflux reaction time in step (1) is 3-8 hours.

[0020] Furthermore, the eluent used in the silica gel column chromatography in step (1) is a mixture of petroleum ether and ethyl acetate, with a volume ratio of 100-10:1.

[0021] Furthermore, in step (2), the catalyst is piperidine and the solvent is ultra-dry acetonitrile.

[0022] Furthermore, in step (2), the molar ratio of compound 1 to compound 2 is 1:0.5-1.

[0023] Furthermore, the reflux reaction time in step (2) is 8-14 hours.

[0024] Furthermore, the eluent used in the silica gel column chromatography in step (2) is a mixture of petroleum ether and ethyl acetate, with a volume ratio of 100-1:1.

[0025] In order to achieve the third objective, the present invention discloses an application of the aggregation-induced emission fluorescent probe described above in the preparation of a product for detecting cuprous ions Cu(I).

[0026] To achieve the fourth objective, the present invention discloses a method for detecting cuprous ions Cu(I) based on the aggregation-induced emission fluorescent probe as described above, comprising the following steps:

[0027] S1. preparing a probe mother solution using the above-mentioned aggregation-induced emission fluorescent probe;

[0028] S2, adding the test solution to the probe mother solution to obtain a test solution, and diluting the probe mother solution with a solvent to obtain a probe reference solution, so that the final concentrations of the aggregation-induced emission fluorescent probe in the test solution and the probe reference solution are the same;

[0029] S3. Based on the comparison of the emission peak fluorescence intensity of the probe reference solution and the test solution, determine whether the test solution contains cuprous ions Cu(I).

[0030] Further, step S3 is specifically as follows:

[0031] The emission peak fluorescence intensity of the probe reference solution and the test solution at 615 nm is tested respectively. If the emission peak fluorescence intensity of the test solution decreases compared with that of the probe reference solution, the test solution contains cuprous ions Cu(I). If the emission peak fluorescence intensity of the test solution does not change compared with that of the probe reference solution, the test solution does not contain cuprous ions Cu(I).

[0032] Furthermore, during the detection process, the final concentration of the aggregation-induced emission fluorescent probe was guaranteed to be above 10 μM.

[0033] Based on the above application, the present invention also explored the fluorescence response test of Cu(II) with different concentration gradients after reduction, and determined that as the concentration of generated Cu(I) increased, the emission peak intensity at 615nm gradually decreased, with obvious fluorescence changes.

[0034] Based on the above application, the present invention also explores the fluorescence response changes of the aggregation-induced luminescence fluorescent probe to common metal ions and reactive oxygen species in cells, and tests the fluorescence response changes after adding metal ions and reactive oxygen species to the probe mother solution, wherein the metal ions include Na + , K + ,Mg 2+ , Ca 2+ , Mn 2+ ,Co 2+ , Ni 2+ , Cu 2+ , Zn 2+ and Cu + , reactive oxygen species include H2O2, ONOO - and ClO - Due to the specific coordination between the NS4 structural unit and Cu(Ⅰ), the fluorescence intensity changes significantly only when Cu(Ⅰ) is added. The addition of other metal ions or reactive oxygen species has no obvious effect on the fluorescence of the aggregation-induced emission fluorescent probe.

[0035] Based on the above application, the present invention further explored the in-situ detection of the reduction of Cu(II) to Cu(I) by aggregation-induced emission fluorescent probe. By real-time monitoring of the fluorescence signal of the system, a trend of gradually decreasing emission peak intensity at 615 nm of the system was shown.

[0036] The beneficial effects of the present invention are as follows:

[0037] The present invention discloses an aggregation-induced luminescence fluorescent probe for detecting cuprous ions Cu(I). The fluorescent probe uses bis(2-((2-(ethyl sulfide)ethyl)-thio)ethyl)amine (NS4) rich in thioether as a Cu(I) recognition unit and a chromophore quinoline nitrile derivative as an AIE structural unit. The fluorescent probe has the following characteristics:

[0038] 1. The fluorescence intensity of the fluorescent probe provided by the present invention increases with the increase of water content, and has an obvious AIE effect.

[0039] 2. As the concentration of Cu(I) increases, the emission peak intensity at 615 nm of the fluorescent probe provided by the present invention gradually decreases, and has obvious fluorescence changes, which can achieve high-sensitivity detection of Cu(I), and its detection limit LOD is 2.03×10 -7 M.

[0040] 3. Since the fluorescent probe of the present invention has a high basic fluorescence, it can resist photobleaching, so that the fluorescent probe can achieve long-term monitoring of Cu(I).

[0041] 4. The fluorescent probe provided by the present invention is not interfered by a variety of metal ions and reactive oxygen species, wherein the metal ions include Na + , K + ,Mg 2+ , Ca 2+ , Mn 2+ ,Co 2+ , Ni 2+ , Cu 2+ , Zn 2+ and Cu + , reactive oxygen species include H2O2, ONOO - and ClO - Only after the addition of Cu(Ⅰ), the fluorescence intensity changes significantly, so that highly selective detection of Cu(Ⅰ) can be achieved, and the process of reduction of Cu(Ⅱ) to Cu(Ⅰ) can be detected in situ.

[0042] 5. The fluorescent probe provided by the present invention emits weak light in a dispersed state, so it is expected to avoid interference from background signals when used for cell Cu(I) imaging, has a high signal-to-noise ratio, and does not require additional washing steps to remove non-aggregated fluorescent probes in cell imaging. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The specific implementation modes of the present invention are further described in detail below in conjunction with the accompanying drawings.

[0044] Figure 1 The compound 1 of the present invention 1 HNMR spectrum.

[0045] Figure 2 The fluorescent probe QM-NS4 of the present invention 1 HNMR spectrum.

[0046] Figure 3 This is a test of the AIE property of the fluorescent probe QM-NS4 of the present invention; the inset shows the change in relative fluorescence intensity at the emission peak of 615 nm as the water content changes.

[0047] Figure 4 This is a response test of the AIE type fluorescent probe QM-NS4 of the present invention to Cu(Ⅰ).

[0048] Figure 5 This is the response curve of the AIE type fluorescent probe QM-NS4 of the present invention to different concentrations of Cu(Ⅰ).

[0049] Figure 6 This is the selectivity test result of the AIE type fluorescent probe QM-NS4 of the present invention.

[0050] Figure 7 The figure shows the stability of the AIE type fluorescent probe QM-NS4 of the present invention and the test results of in-situ detection of reduction of Cu(II) to Cu(I); the inset shows the color change of the system before and after the response to Cu(I). DETAILED DESCRIPTION

[0051] In order to more clearly illustrate the present invention, the present invention is further described below in conjunction with preferred embodiments and accompanying drawings. Similar components in the accompanying drawings are represented by the same reference numerals. It should be understood by those skilled in the art that the content specifically described below is illustrative rather than restrictive, and should not be used to limit the scope of protection of the present invention.

[0052] Unless otherwise specified, the raw materials used in the present invention can be obtained commercially. Any range recorded in the present invention includes the end value and any numerical value between the end values ​​and any sub-range formed by the end value or any numerical value between the end values.

[0053] Example 1

[0054] Synthesis of compound 1

[0055]

[0056] Sodium ethoxide (0.408 g, 6 mmol) was dissolved in anhydrous ethanol (12 mL), and 2-(ethylthio)ethanethiol (0.5 mL, 4 mmol) and 4-[bis-(2-chloroethyl)amino]benzaldehyde (0.5 g, 2 mmol) were added thereto. The mixture was stirred at reflux at 80°C for 4 h under nitrogen atmosphere. After the reaction, deionized water (20 mL) was added to the system, and then extracted with dichloromethane (20 mL×3). The organic phase was washed with deionized water (20 mL×1) and saturated brine (20 mL×1), dried with a small amount of anhydrous sodium sulfate, filtered, and concentrated. The mixture was separated and purified by silica gel column chromatography, and the eluent was petroleum ether and ethyl acetate (10 / 1, v / v) to obtain compound 1 as an orange oil. Among them, compound 1 1 HNMR spectrum Figure 1 shown.

[0057] Synthesis of AIE-type fluorescent probe QM-NS4

[0058] Piperidine (0.2 mL) and acetonitrile (12 mL) were added to compound 1 (150 mg, 0.359 mmol) and 2-(1-ethyl-2-methylquinolin-4(1H)-ylidene)malononitrile (85 mg, 0.359 mmol), and the mixture was stirred under reflux at 90°C for 10 h under nitrogen atmosphere. After the reaction, the solvent was concentrated and separated and purified by silica gel column chromatography. The eluent was petroleum ether and ethyl acetate (1 / 1, v / v) to obtain an orange-red solid compound, namely QM-NS4. 1 HNMR spectrum Figure 2 shown.

[0059] Preparation of probe stock solution

[0060] Preparation of 1 mM QM-NS4 probe stock solution: Accurately weigh 6.3 mg QM-NS4 probe molecules on an analytical balance, use a pipette to transfer 10 mL of dimethyl sulfoxide (DMSO) to dissolve the sample, prepare a 1 mM probe stock solution, wrap it in tin foil and store it in a refrigerator at 4°C away from light for later use. The following examples prepare the probe stock solution according to the same method.

[0061] Example 2

[0062] Synthesis of compound 1

[0063] Sodium ethoxide (0.408 g, 6 mmol) was dissolved in anhydrous ethanol (12 mL), and 2-(ethylthio)ethanethiol (0.5 mL, 4 mmol) and 4-[bis-(2-chloroethyl)amino]benzaldehyde (0.5 g, 2 mmol) were added thereto. The mixture was refluxed at 80 °C with stirring for 6 h under nitrogen atmosphere. After the reaction, deionized water (20 mL) was added to the system, followed by extraction with dichloromethane (20 mL×3). The organic phase was washed with deionized water (20 mL×1) and saturated brine (20 mL×1), respectively, and dried over a small amount of anhydrous sodium sulfate, filtered, and concentrated. The mixture was separated and purified by silica gel column chromatography with petroleum ether and ethyl acetate (10 / 1, v / v) as the eluent to obtain compound 1 as an orange oil.

[0064] Synthesis of AIE-type fluorescent probe QM-NS4

[0065] To compound 1 (150 mg, 0.359 mmol) and 2-(1-ethyl-2-methylquinolin-4(1H)-ylidene)malononitrile (85 mg, 0.359 mmol) were added catalyst piperidine (0.2 mL) and solvent ultra-dry acetonitrile (12 mL), and the mixture was refluxed at 90 °C for 12 h under a nitrogen atmosphere. After the reaction, the solvent was concentrated and the mixture was separated and purified by silica gel column chromatography with petroleum ether and ethyl acetate (1 / 1, v / v) as the eluent to obtain an orange-red solid compound, QM-NS4.

[0066] Determination of the AIE properties of the probe

[0067] Preparation of blank solution: In a 50mL conical flask, add 50mL, 45mL, 40mL, 35mL, 30mL, 25mL, 20mL, 15mL, 10mL, 5mL, and 0mL of anhydrous ethanol, and then add ultrapure water to make the total volume 50mL to prepare a series of C2H5OH / H2O mixed solvents with a water volume fraction of f w They are 0 (pure C2H5OH), 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% and 100% respectively, and are prepared for use.

[0068] Test of the AIE property of the probe: 1.98 mL of the blank solution prepared in advance was added to a 10 mm cuvette, and 20 μL of 1 mM QM-NS4 probe mother solution was added thereto to obtain a C2H5OH / H2O mixed solution of QM-NS4 with a water content ranging from 0% to 99%. The fluorescence spectra of the fluorescent probe in solutions with different water contents were tested using a fluorescence spectrometer. The changes in the fluorescence emission spectrum are shown in Figure 3 The inset shows the relative fluorescence intensity change at the emission peak of 615 nm as the water content changes. Figure 3As can be seen from the figure and its illustration, the AIE-type fluorescent probe QM-NS4 has obvious aggregation fluorescence enhancement performance with the increase of water content.

[0069] In order to ensure the dispersibility of the fluorescent probe in the solution, the volume fraction of water f was selected in subsequent experiments. w =70% was tested as the test solution.

[0070] Example 3

[0071] Synthesis of compound 1

[0072] Sodium ethoxide (0.408 g, 6 mmol) was dissolved in anhydrous ethanol (12 mL), and 2-(ethylthio)ethanethiol (0.5 mL, 4 mmol) and 4-[bis-(2-chloroethyl)amino]benzaldehyde (0.5 g, 2 mmol) were added thereto. The mixture was refluxed at 80 °C with stirring for 8 h under nitrogen atmosphere. After the reaction, deionized water (20 mL) was added to the system, followed by extraction with dichloromethane (20 mL×3). The organic phase was washed with deionized water (20 mL×1) and saturated brine (20 mL×1), respectively, and dried over a small amount of anhydrous sodium sulfate, filtered, and concentrated. The mixture was separated and purified by silica gel column chromatography with petroleum ether and ethyl acetate (10 / 1, v / v) as the eluent to obtain compound 3 as an orange oil.

[0073] Synthesis of AIE-type fluorescent probe QM-NS4

[0074] To compound 1 (150 mg, 0.359 mmol) and 2-(1-ethyl-2-methylquinolin-4(1H)-ylidene)malononitrile (85 mg, 0.359 mmol) were added catalyst piperidine (0.2 mL) and solvent ultra-dry acetonitrile (12 mL), and the mixture was refluxed at 90 °C under nitrogen atmosphere for 14 h. After the reaction, the solvent was concentrated and the mixture was separated and purified by silica gel column chromatography with petroleum ether and ethyl acetate (1 / 1, v / v) as the eluent to obtain an orange-red solid compound, QM-NS4.

[0075] Determination of the fluorescence emission spectrum changes of the probe in response to Cu(Ⅰ)

[0076] Preparation of stock buffer: Accurately pipette 3.75 mL of 4-hydroxyethylpiperazineethanesulfonic acid (HEPES, 1 M), 45 mL of anhydrous ethanol, and 101.25 mL of ultrapure water into a 250 mL conical flask to prepare a stock buffer containing 25 mM HEPES, and the volume fraction of water is f w =70%.

[0077] Use the stock buffer to accurately prepare a concentration of 100mM Na + , K + ,Mg 2+ , Ca2+ , AANa, H2O2 aqueous solution, Mn with a concentration of 1mM 2+ ,Co 2+ , Ni 2+ , Cu 2+ , Zn 2+ aqueous solution and 10 mM ClO - 、ONOO - of aqueous solution.

[0078] Probe response test to Cu(Ⅰ): 20 μL QM-NS4 probe stock solution was added to a 10 mm cuvette, and a certain amount of reserve buffer solution was added thereto, and 20 μL Cu(Ⅱ) solution, 20 μL AANa solution, 20 μL Cu(Ⅱ) and 20 μL sodium ascorbate (AANa) solution were added thereto to make the final volume 2 mL. The fluorescence spectra of the probe response to Cu(Ⅱ), AANa and Cu(Ⅰ) were tested using a fluorescence spectrometer. The changes in the fluorescence emission spectra are shown in Figure 4 .

[0079] Probe response test to different concentrations of Cu(Ⅰ): Add 20μL QM-NS4 probe stock solution to a 10mm cuvette, add a certain amount of reserve buffer solution and 20μL AANa solution, and add 0-20μL Cu(Ⅱ) solution to make the final volume 2mL. Use a fluorescence spectrometer to test the fluorescence spectrum of the probe in response to different concentrations of Cu(Ⅰ) solution. The changes in the fluorescence emission spectrum are shown in Figure 5 .

[0080] from Figure 4 and Figure 5 It can be seen that the fluorescent probe has a good response to Cu(Ⅰ), and with the increase of Cu(Ⅰ) concentration, the fluorescence intensity of the fluorescent probe at 615nm gradually decreases, and its detection limit LOD is 2.03×10 -7 M.

[0081] Selectivity test of the probe for Cu(Ⅰ): 20 μL QM-NS4 probe stock solution was added to a 10 mm cuvette, and a certain amount of reserve buffer solution and 20 μL of the interfering substance to be tested were added thereto to make the final volume 2 mL. The interfering substance to be tested was selected from Na + , K + ,Mg 2+ , Ca 2+ , Mn 2+ ,Co 2+ , Ni 2+ , Cu 2+ , Zn 2+ , AANa, H2O2, ClO - ,ONOO -or Cu(Ⅰ), the fluorescence spectrum of the fluorescent probe to each interfering substance was tested by fluorescence spectrometer, and the fluorescence intensity at the emission peak of 615nm was shown in Figure 6 .from Figure 6 It can be seen that only after the addition of Cu(Ⅰ), the fluorescence intensity changes significantly, indicating that the fluorescent probe has very good selectivity for Cu(Ⅰ).

[0082] Stability of the probe and the process of in-situ detection of reduction of Cu(Ⅱ) to Cu(Ⅰ): 20μL QM-NS4 probe stock solution was added to a 10mm cuvette, a certain amount of reserve buffer solution and 20μL AANa solution were added thereto, and 0 and 20μL Cu(Ⅱ) solution were added thereto respectively, so that the final volume was 2mL. The fluorescence spectra of the probe and the response of the probe to the Cu(Ⅰ) solution over time were tested by fluorescence spectrometer. The changes in the fluorescence emission spectrum are shown in Fig. Figure 7 The inset shows the color change of the system before and after the probe responds to Cu(Ⅰ). Figure 7 As can be seen from the illustration, the fluorescent probe has good stability and can be used to test the reduction of Cu(Ⅱ) to Cu(Ⅰ) in situ. During this process, the fluorescence intensity of the fluorescent probe at 615 nm gradually weakens, and the color of the system changes from orange to yellow.

[0083] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not limitations on the implementation methods of the present invention. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the implementation methods here. All obvious changes or modifications derived from the technical solution of the present invention are still within the protection scope of the present invention.

Claims

1. An aggregation-induced luminescence fluorescent probe for detecting cuprous ions Cu(I), characterized in that: The structure of the aggregation-induced emission fluorescent probe is shown in Formula I below; Wherein, R is selected from one of H, an alkyl group with carbon atoms ranging from C1 to C4, and COOH.

2. The aggregation-induced emission fluorescent probe according to claim 1, characterized in that: The R is selected from methyl or COOH.

3. The method for preparing the aggregation-induced emission fluorescent probe according to claim 1 or 2, characterized in that: The steps include: (1) dissolving sodium ethoxide, 4-[bis-(2-chloroethyl)amino]benzaldehyde and 2-(ethylthio)ethanethiol in anhydrous ethanol, and reacting under reflux in an inert atmosphere. After the reaction, deionized water is added to the system, and the mixture is extracted with dichloromethane. The organic phase is washed with deionized water and saturated brine in sequence, dried over anhydrous sodium sulfate, concentrated, and separated and purified by column chromatography to obtain compound 1; (2) Compound 1, Compound 2 and a catalyst are added to a solvent, and refluxed under a nitrogen atmosphere for reaction. After the reaction is completed, the mixture is concentrated, separated and purified by column chromatography to obtain the product.

4. The preparation method according to claim 3, characterized in that: The molar ratio of sodium ethoxide, 2-(ethylthio)ethanethiol, and 4-[bis-(2-chloroethyl)amino]benzaldehyde in step (1) is 3:2:0.5-1; The molar volume ratio of the sodium ethoxide to ethanol is 1 mmol:(1.5-2) mL.

5. The preparation method according to claim 3, characterized in that: The reflux reaction time in step (1) is 3-8h; The reflux reaction time in step (2) is 8-14h.

6. The preparation method according to claim 3, characterized in that: The catalyst in step (2) is piperidine and the solvent is ultra-dry acetonitrile.

7. The preparation method according to claim 3, characterized in that: The molar ratio of compound 1 to compound 2 in step (2) is 1:0.5-1.

8. Use of the aggregation-induced emission fluorescent probe as claimed in claim 1 or 2 in the preparation of a product for detecting cuprous ions Cu(I).

9. A method for detecting cuprous ions Cu(I) based on aggregation-induced emission fluorescent probe, characterized in that: The steps include: S1. preparing a probe mother solution using the aggregation-induced emission fluorescent probe according to claim 1 or 2; S2, adding the test solution to the probe mother solution to obtain a test solution, and diluting the probe mother solution with a solvent to obtain a probe reference solution, so that the final concentrations of the aggregation-induced emission fluorescent probe in the test solution and the probe reference solution are the same; S3. Based on the comparison of the emission peak fluorescence intensity of the probe reference solution and the test solution, determine whether the test solution contains cuprous ions Cu(I).

10. The detection method according to claim 9, characterized in that: Step S3 is specifically as follows: The emission peak fluorescence intensity of the probe reference solution and the test solution at 615 nm is tested respectively. If the emission peak fluorescence intensity of the test solution decreases compared with that of the probe reference solution, the test solution contains cuprous ions Cu(I). If the emission peak fluorescence intensity of the test solution does not change compared with that of the probe reference solution, the test solution does not contain cuprous ions Cu(I).

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