A mesoporous silica hydrogen peroxide fluorescent nanoprobe with aggregation-induced emission effect and its preparation method

Abstract

The present invention discloses a mesoporous silica (MSNs) hydrogen peroxide fluorescent nanoprobe with aggregation-induced emission effect (AIE) and a preparation method, which belongs to the technical field of organic-inorganic hybrid nanomaterials. The probe includes a mesoporous silica material and a hydrogen peroxide-responsive fluorescent molecule with AIE. The CN functional molecule that responds to H2O2 is prepared by a two-step synthesis, and CN is further reacted with 3-iodopropyltrimethoxysilane to obtain a condensable silane precursor (CN-Si). Using surfactant micelles as templates, CN-Si and tetraethyl orthosilicate are used to prepare the H2O2 fluorescent nanoprobe by a one-step co-condensation method. On the one hand, the fluorescent probe based on the MSNs can ensure its luminous efficiency through the fixation of silica nanomaterials, and on the other hand, the protective effect of the material skeleton can well improve the photostability of the CN fluorescent organic molecules, thereby ensuring the effective sensing of the probe.

Description

Technical Field

[0001] The present invention relates to the technical field of organic-inorganic hybrid nanomaterials, in particular to a mesoporous silica hydrogen peroxide fluorescent nanoprobe with aggregation-induced luminescence effect and a preparation method thereof. Background Art

[0002] Fluorescent silica organic-inorganic hybrid nanomaterials effectively combine the luminescent properties of organic fluorescent dyes with the structural advantages of silica nanomaterials, attracting increasing research interest. Silica materials offer excellent biocompatibility, photochemical stability, and water dispersibility, as well as ease of functional modification, providing an excellent support for the assembly of various luminescent materials. However, conventional organic fluorescent molecules aggregate upon incorporation into the silica backbone, leading to aggregation-induced fluorescence quenching (ACQ), a phenomenon that severely impacts the performance of these fluorescent materials in sensing and biomedical applications. The discovery of aggregation-induced emission luminescent molecules (AIEgens) has opened up a new avenue for the design and synthesis of high-performance fluorescent nanomaterials. The aggregation and immobilization of AIEgens within silica nanomaterials, resulting in restricted intramolecular rotation, can in turn enhance the fluorescence of the luminophore and increase its quantum yield, thereby yielding highly efficient MSN fluorescent nanoprobes. Furthermore, the protective effect of the silica backbone significantly improves the photostability of AIEgens, providing a promising foundation for practical applications.

[0003] Hydrogen peroxide (H2O2) plays a crucial role in drug synthesis, environmental monitoring, clinical applications, and food production. It is also a product of numerous enzymatic reactions in organisms. Therefore, its detection is of great practical significance. Currently, the main methods for detecting H2O2 include spectrophotometry, chemiluminescence, electrochemistry, and fluorescence. Some of these methods suffer from long analysis times, expensive reagents, and the use of toxic reagents. Therefore, the development of simple, sensitive, and non-toxic hydrogen peroxide sensors is highly desirable. Summary of the Invention

[0004] One of the objectives of the present invention is to design a fluorescent nanoprobe that can achieve highly sensitive and selective detection of hydrogen peroxide, while overcoming the drawbacks of fluorescent dye probes, such as poor photostability and aggregation-induced quenching. This invention provides an organic fluorescent probe that exhibits aggregation-induced emission (AIE) properties and responds to hydrogen peroxide. The fluorescent nanoprobe is introduced into a MSN material via a co-condensation method. While maintaining the original phase structure of the MSN, the fluorescent efficiency and detection sensitivity are effectively improved. Furthermore, the backbone protects the fluorescent groups, preventing photobleaching.

[0005] This invention provides a method for preparing a MSN-based H2O2 fluorescent nanoprobe with an AIE effect. This material utilizes a fluorescent cyanostyrene borate siloxane organic molecule (CN-Si) with an AIE effect and tetraethyl silicate through co-assembly to synthesize the MSN material with AIE effect in a single step. This method not only improves the photostability of the CN fluorescent organic molecule, but also enhances its luminous efficiency through the immobilization of the silica nanomaterial, achieving efficient and stable H2O2 sensing performance.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] The present invention provides a method for preparing a mesoporous silica hydrogen peroxide fluorescent nanoprobe with aggregation-induced emission effect, comprising a mesoporous silica material (MSN) and a hydrogen peroxide-responsive fluorescent molecule with aggregation-induced emission effect (AIE);

[0008] The mesoporous silica material is used as a skeleton to fix hydrogen peroxide-responsive fluorescent molecules with aggregation-induced emission effect;

[0009] The hydrogen peroxide-responsive fluorescent molecules with aggregation-induced emission effect are fixed on the pore wall of the MSN through covalent bonds.

[0010] Furthermore, the hydrogen peroxide-responsive fluorescent molecule with aggregation-induced emission effect is a cyanostyrene-based borate (CN) fluorescent organic molecule.

[0011] The borate fluorescent organic molecule based on cyanostyrene of the present invention has an AIE effect, and its optical stability can be significantly improved after being modified on the interface of a porous material.

[0012] The present invention provides a method for preparing a mesoporous silica hydrogen peroxide fluorescent nanoprobe with aggregation-induced emission effect, comprising the following steps:

[0013] (1) An intermediate organic compound 1 is prepared by reacting N,N-dimethylbenzaldehyde and p-bromophenylacetonitrile. The structural formula of the intermediate organic compound 1 is as follows:

[0014]

[0015] (2) The intermediate organic compound 1 reacts with bis(pinacolato)diboron to obtain a hydrogen peroxide-responsive fluorescent molecule (CN) with aggregation-induced emission effect, the structural formula of which is as follows:

[0016]

[0017] (3) 3-chloropropyltrimethoxysilane undergoes a halogen exchange reaction with NaI to prepare 3-iodopropyltrimethoxysilane;

[0018] (4) the hydrogen peroxide-responsive fluorescent molecule with aggregation-induced emission effect in step (2) undergoes a quaternization reaction with 3-iodopropyltrimethoxysilane to prepare a cyanostyrene borate-based siloxane (CN-Si) fluorescent organic molecule;

[0019] (5) Tetraethyl orthosilicate (TEOS) and CN-Si were co-condensed to obtain the final mesoporous silica-based hydrogen peroxide fluorescent nanoprobe (CN-MSN) with aggregation-induced emission effect.

[0020] The present invention utilizes a cyanostyrene borate siloxane fluorescent organic molecule (CN-Si) exhibiting the AIE effect and tetraethyl orthosilicate through co-assembly to synthesize a MSN material exhibiting the AIE effect in a single step. A cyanostyrene-based borate fluorescent organic molecule (CN) that responds to H2O2 is first prepared through a two-step synthesis. 3-Chloropropyltrimethoxysilane is reacted with sodium iodide to prepare 3-iodopropyltrimethoxysilane; CN reacts with 3-iodopropyltrimethoxysilane to prepare a condensable silane precursor (CN-Si); this precursor is reacted with tetraethyl orthosilicate, and a surfactant is used as a template to prepare a MSN-based H2O2 fluorescent nanoprobe (CN-MSN) exhibiting the AIE effect through co-condensation. This method not only improves the photostability of the CN fluorescent organic molecule, but also increases its luminous efficiency through the immobilization of the silica nanomaterial, thereby enhancing its H2O2 sensing performance.

[0021] Furthermore, the molar ratio of N,N-dimethylbenzaldehyde to p-bromophenylacetonitrile in step (1) is 1:1.

[0022] Furthermore, in step (2), the molar ratio of the intermediate organic compound 1 to bis(pinacolato)diboron is 3:4.

[0023] Furthermore, the molar ratio of 3-chloropropyltrimethoxysilane to NaI in step (3) is 2:3.

[0024] Furthermore, the specific steps for preparing the siloxane fluorescent organic molecule based on cyanostyrene borate in step (4) are as follows: CN and 3-iodopropyltrimethoxysilane are heated in ethyl acetate at a molar ratio of 5:6, excess potassium carbonate is added as a catalyst, the mixture is refluxed for 72 hours, the catalyst is filtered to remove, and part of the solvent is removed by distillation under reduced pressure. The remaining reaction mixture is cooled to room temperature, n-hexane is added, solid CN-Si is precipitated, and after standing for half an hour, the supernatant is precipitated, n-hexane is added again, ultrasonication is performed, and the mixture is allowed to stand for half an hour. The mixture is washed repeatedly three times, the solid is filtered out, and dried to obtain a pure CN-Si solid, whose structural formula is as follows:

[0025]

[0026] Furthermore, the specific preparation steps of the hydrogen peroxide fluorescent nanoprobe with aggregation-induced emission effect in step (5) are as follows: using hexadecyltrimethylammonium bromide (CTAB) as a template, adjusting the pH of the aqueous solution with sodium hydroxide solution to prepare a CTAB aqueous solution, using tetraethyl orthosilicate (TEOS) as an inorganic silane precursor, and simultaneously dropping the above-synthesized CN-Si as an organic silicon precursor into the CTAB aqueous solution under stirring conditions. After the addition is complete, the mixed solution is stirred at 80° C. for 1 hour and then cooled to room temperature, filtered to obtain a CN-MSN material, and the obtained CN-MSN is refluxed in a methanol / hydrochloric acid solution for 24 hours to remove the CTAB surfactant template, filtered, and vacuum dried.

[0027] Furthermore, the molar ratio of hexadecyltrimethylammonium bromide to sodium hydroxide is 1:2.55, and the mass ratio of TEOS to CN-Si is 20:1.

[0028] The present invention also provides application of the mesoporous silica-based hydrogen peroxide fluorescent nanoprobe with aggregation-induced emission effect in detecting hydrogen peroxide.

[0029] The present invention discloses the following technical effects:

[0030] (1) The present invention utilizes a quaternization reaction to synthesize a CN-Si organosilane coupling agent precursor molecule. This molecule retains the AIE effect and hydrogen peroxide sensing performance of the CN molecule while being able to be hydrolyzed and polycondensed by trimethoxysilane to form a stable covalent bond into the silica skeleton.

[0031] (2) The present invention fixes the prepared CN-Si into the MSN material through a one-step co-condensation method. This material can not only effectively avoid ACQ, but also the protection of the MSN matrix can effectively improve the photostability of CN.

[0032] (3) The CN-MSN fluorescent nanoprobe prepared in the present invention can effectively realize the sensing of hydrogen peroxide. Its synthesis method is simple, easy to operate, and the cost of raw materials and instruments and equipment is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0034] Figure 1 The intermediate organic compound 1 prepared in Example 1 1H NMR spectrum;

[0035] Figure 2 The CN molecules prepared in Example 2 1 H NMR spectrum;

[0036] Figure 3 The CN-Si molecules prepared in Example 4 1 H NMR spectrum;

[0037] Figure 4 This is the mass spectrum (MS) of the CN-Si molecule prepared in Example 4;

[0038] Figure 5 Fluorescence emission changes of CN-Si prepared in Example 4 in different water / ethanol mixed solvents;

[0039] Figure 6 Comparison of infrared spectra of CN-MSN materials with CN, CN-Si and pure MSN;

[0040] Figure 7 TEM image of the CN-MSN material in Example 6;

[0041] Figure 8 is the nitrogen adsorption-desorption curve of the CN-MSN material in Example 6;

[0042] Figure 9 The fluorescence spectrum of hydrogen peroxide sensed by CN-MSN in Example 7;

[0043] Figure 10 Schematic diagram of the optical stability of CN-MSN and CN-Si under ultraviolet light in Example 8. DETAILED DESCRIPTION

[0044] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0045] It should be understood that the terms described herein are intended only to describe particular embodiments and are not intended to limit the present invention. In addition, for numerical ranges herein, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. The intermediate value within any stated value or stated range, and each smaller range between any other stated value or intermediate value within the stated range, is also encompassed within the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded within the scope.

[0046] Unless otherwise indicated, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein may also be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of any conflict with any incorporated document, the contents of this specification shall prevail.

[0047] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments described herein without departing from the scope or spirit of the invention. Other embodiments will be apparent to those skilled in the art from the description of the invention. The description and examples are intended to be illustrative only.

[0048] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0049] Example 1

[0050] N,N-dimethylbenzaldehyde (4.0 g, 26.80 mmol) and p-bromophenylacetonitrile (5.24 g, 26.72 mmol) were added to 60 mL of anhydrous methanol. Potassium hydroxide methanol solution (4 mL, 0.5 M) was added while stirring, causing the solution to become turbid. The turbid solution was stirred at room temperature for 3 hours. After standing for 1 hour, the solid precipitate was filtered under reduced pressure and recrystallized from ethanol to obtain a pure yellow solid intermediate organic compound 1, which was then dried under vacuum for 1 day (yield 75%). 1 H NMR (400 MHz, CDCl3) 3.07 (s, 6H, -CH3), 6.75 (d, 2H, ArH), 7.37 (s, 1H, CH), 7.49-7.58 (m, 4H, ArH) and 7.86 (d, J = 10 Hz, 2H, ArH). (Intermediate organic compound 1 prepared in Example 1 1 H NMR spectrum is shown in Figure 1 ).

[0051] Example 2

[0052] The yellow intermediate organic compound 1 (1 g, 3.04 mmol) was dissolved in 30 mL of anhydrous toluene. Under nitrogen, bistriphenylphosphine palladium dichloride (0.04 g, 0.082 mmol), triphenylphosphine (0.04 g, 0.152 mmol), and potassium acetate (0.40 g, 4.17 mmol) were added as catalysts. An excess of bis(pinacolato)diboron (1.03 g, 4.05 mmol) was then added. The molar ratio of 1 to bis(pinacolato)diboron was 3:4. The mixed solution was heated to 110°C and reacted for 8 h. After the reaction, the toluene was removed under reduced pressure, and the product was extracted with dichloromethane. The dichloromethane extract was washed with water, and the organic layer was separated and dried over anhydrous sodium sulfate for 4 h. The anhydrous sodium sulfate was filtered, and the resulting solution was distilled under reduced pressure to remove the solvent. The crude product was purified by column chromatography to obtain a CN molecule with an AIE effect (yield 60%). 1 H NMR (400 MHz, CDCl3) 1.29 (s, 12H, CH3), 3.05 (s, 6H, CH3), 6.68 (d, 2H, ArH), 7.48 (s, 1H, CH), 7.68 (d, 2H, ArH) and 7.75-7.85 (m, 4H, ArH). (CN molecules prepared in Example 2 1 H NMR spectrum is shown in Figure 2 ).

[0053] Example 3

[0054] 3-Chloropropyltrimethoxysilane (30.0 g, 151.0 mmol) and excess NaI (34.0 g, 226.6 mmol) were heated under reflux in 200 mL of acetone for 72 h to undergo a halogen exchange reaction. The excess solvent was removed by distillation under reduced pressure, pentane was added, the sodium salt was removed by filtration, and the solvent was removed by distillation under reduced pressure to obtain colorless oily 3-iodopropyltrimethoxysilane (yield 73%).

[0055] Example 4

[0056] CN (1.00 g, 2.67 mmol) and an excess of 3-iodopropyltrimethoxysilane (0.93 g, 3.21 mmol) were added to ethyl acetate, and potassium carbonate catalyst was added to cause quaternization reaction. The reaction was refluxed for 3 days, cooled to room temperature, filtered to remove the catalyst, and the excess solvent was distilled off under reduced pressure. Then, n-hexane was added to precipitate solid CN-Si. After standing for half an hour, the supernatant was precipitated, and n-hexane was added again. Ultrasonication was performed, and the reaction was allowed to stand for half an hour. The reaction was washed repeatedly three times, and the solid was filtered out and dried to obtain pure CN-Si solid (yield 50%). 1H NMR (400 MHz, CDCl3) 1.36 (s, 12H, CH3), 2.925-3.118 (s, 6H, CH3), 3.238 (s, 1H, OCH3), 6.575-6.667 (m, 1H, ArH), 6.777-6.860 (m, 1H, ArH), 7.083 (d, 1H, ArH), 7.398-7.506 (m, 2H, CH and ArH), 7.607-7.674 (m, 1H, ArH) and 7.765–7.928 (m, 3H, ArH), (the CN-Si molecule prepared in Example 4) 1 H NMR spectrum is shown in Figure 3 ). ESI+HR-MS calcd for CNSB-Si[M+H] + 537.56, found: 537.3, (The mass spectrum (MS) of the CN-Si molecule prepared in Example 4 is shown in Figure 4 Note: During the NMR characterization process, the methoxy group (-OCH3) hydrolyzed, resulting in only one H in the methoxy group at 3.238 ppm.

[0057] Example 5

[0058] The aggregation-induced emission enhancement effect of CN-Si is demonstrated by the fluorescence emission spectra and luminescence photos of CN-Si molecules in water / ethanol mixed solutions with different ratios. CN-Si molecules can be well dissolved in anhydrous ethanol solution, but with the addition of poor solvent water, the CN-Si solution gradually becomes turbid and aggregates. At this time, the fluorescence intensity of the aggregated CN-Si also shows an increasing trend as the turbidity of the solution increases, which further proves that CN-Si molecules have the AIE effect (the fluorescence emission changes of CN-Si prepared in Example 4 in different water / ethanol mixed solvents are detailed in Figure 5 ).

[0059] Example 6

[0060] CTAB (200 mg) and sodium hydroxide (350 μL, 4 M) were dissolved in 100 mL of deionized water and heated to 80°C with stirring for 1 h. 1 g of TEOS and 0.1 g of CN-Si were added to the CTAB aqueous solution while stirring. The mixed solution was stirred at 80°C for 2 h and then cooled to room temperature. The CN-MSN material was obtained by filtration. The infrared spectrum showed that CN was successfully connected to MSN (see the infrared spectrum comparison of CN-MSN material and CN, CN-Si and pure MSN for details). Figure 6The resulting CN-MSN material was refluxed in a methanol / hydrochloric acid (16:1 v / v) solution for 24 hours, the surfactant template CTAB was removed, the material was filtered, and vacuum dried. The infrared spectrum of the resulting CN-MSN material was compared with the spectra of CN, CN-Si, and MSN. The infrared spectrum of the CN-MSN material showed that the infrared spectrum of the CN-MSN material had the stretching and bending vibration peaks of the intramolecular chemical bond of CN, and also had the stretching and bending vibration peaks of the Si-O-Si of the MSN material.

[0061] The transmission electron microscope (TEM) image of the CN-MSN material prepared in Example 6 of the present invention is shown in FIG. Figure 7 It can be seen that the above hybrid mesoporous materials exhibit good pore structure.

[0062] The nitrogen adsorption-desorption curve of the CN-MSN material prepared in Example 6 of the present invention is shown in FIG. Figure 8 It can be seen that the above hybrid mesoporous materials have good specific surface area and pore structure.

[0063] Example 7

[0064] CN-MSNs were dispersed in PBS aqueous solution (PBS / ethanol = 99 / 1), and different amounts of hydrogen peroxide (1-2×10 -4 After standing at room temperature for 1 hour, the CN-MSN solution was compared before and after the addition of hydrogen peroxide. It was found that the nanoprobe exhibited good hydrogen peroxide fluorescence response properties (see Example 7 for details of the CN-MSN sensing hydrogen peroxide fluorescence spectrum). Figure 9 ).

[0065] Example 8

[0066] Comparing the photostability of CN-MSN and CN-Si, the PBS aqueous solution (PBS / ethanol = 99 / 1, volume ratio) of the above materials and molecules was illuminated under ultraviolet light and the changes in their fluorescence over time were observed. A 90-minute tracking experiment found that CN-MSN could still retain more than 80% of its fluorescence intensity after 90 minutes of continuous ultraviolet light irradiation, while CN-Si lacked the protective effect of the silica skeleton and its fluorescence dropped to 60% (see the schematic diagram of the optical stability of CN-MSN and CN-Si under ultraviolet light irradiation in Example 8 for details). Figure 10 The above results prove that the protective effect of the CN-MSN material skeleton effectively improves the stability of the probe.

[0067] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. Application of a mesoporous silica hydrogen peroxide fluorescent nanoprobe with aggregation-induced emission effect in the detection of hydrogen peroxide, characterized in that: The mesoporous silica hydrogen peroxide fluorescent nanoprobe with aggregation-induced emission effect comprises a mesoporous silica material and a hydrogen peroxide-responsive fluorescent molecule with aggregation-induced emission effect; The mesoporous silica material is used as a skeleton to fix hydrogen peroxide-responsive fluorescent molecules with aggregation-induced emission effect; The hydrogen peroxide-responsive fluorescent molecules with aggregation-induced emission effect are fixed to the pore walls of the mesoporous silica material by chemical bonds through a co-condensation method; The hydrogen peroxide-responsive fluorescent molecule with aggregation-induced emission effect is a cyanostyrene-based borate fluorescent organic molecule; The method for preparing the mesoporous silica hydrogen peroxide fluorescent nanoprobe with aggregation-induced emission effect comprises the following steps: (1) An intermediate organic compound 1 is prepared by reacting N,N-dimethylbenzaldehyde and p-bromophenylacetonitrile. The structural formula of the intermediate organic compound 1 is as follows: ； (2) The intermediate organic compound 1 reacts with bis(pinacolato)diboron to obtain a hydrogen peroxide-responsive fluorescent molecule with aggregation-induced emission effect, the structural formula of which is as follows: ； (3) 3-Chloropropyltrimethoxysilane undergoes a halogen exchange reaction with NaI to prepare 3-iodopropyltrimethoxysilane; (4) The hydrogen peroxide-responsive fluorescent molecule with aggregation-induced emission effect in step (2) undergoes a quaternization reaction with 3-iodopropyltrimethoxysilane to prepare a siloxane fluorescent organic molecule based on cyanostyrene borate, the structural formula of which is as follows: ； (5) Tetraethyl orthosilicate was co-condensed with a siloxane fluorescent organic molecule based on cyanostyrene borate to obtain the final aggregation-induced emission effect of mesoporous silica hydrogen peroxide fluorescent nanoprobe.

2. A method for preparing the mesoporous silica hydrogen peroxide fluorescent nanoprobe with aggregation-induced emission effect as claimed in claim 1, characterized in that: The steps include: (1) An intermediate organic compound 1 is prepared by reacting N,N-dimethylbenzaldehyde and p-bromophenylacetonitrile. The structural formula of the intermediate organic compound 1 is as follows: ； (2) The intermediate organic compound 1 reacts with bis(pinacolato)diboron to obtain a hydrogen peroxide-responsive fluorescent molecule with aggregation-induced emission effect, the structural formula of which is as follows: ； (3) 3-Chloropropyltrimethoxysilane undergoes a halogen exchange reaction with NaI to prepare 3-iodopropyltrimethoxysilane; (4) The hydrogen peroxide-responsive fluorescent molecule with aggregation-induced emission effect in step (2) undergoes a quaternization reaction with 3-iodopropyltrimethoxysilane to prepare a siloxane fluorescent organic molecule based on cyanostyrene borate, the structural formula of which is as follows: ； (5) Tetraethyl orthosilicate was co-condensed with a siloxane fluorescent organic molecule based on cyanostyrene borate to obtain the final aggregation-induced emission effect of mesoporous silica hydrogen peroxide fluorescent nanoprobe.

3. The preparation method according to claim 2, characterized in that: The molar ratio of the N,N-dimethylbenzaldehyde to the p-bromophenylacetonitrile in step (1) is 1:

1.

4. The preparation method according to claim 2, characterized in that The molar ratio of the intermediate organic compound 1 to the bis(pinacolato)diboron in step (2) is 3:

4.

5. The preparation method according to claim 2, characterized in that: The molar ratio of the 3-chloropropyltrimethoxysilane to the NaI in step (3) is 2:

3.

6. The preparation method according to claim 2, characterized in that: The specific steps for preparing the cyanostyrene borate-based siloxane fluorescent organic molecule described in step (4) are as follows: a hydrogen peroxide-responsive fluorescent molecule having an aggregation-induced emission effect and 3-iodopropyltrimethoxysilane are heated in ethyl acetate at a molar ratio of 5:6, an excess of potassium carbonate is added as a catalyst, the mixture is refluxed for 72 hours, the catalyst is removed by filtration, and excess solvent is removed by distillation under reduced pressure. The remaining reaction mixture is cooled to room temperature, n-hexane is added, and a solid cyanostyrene borate-based siloxane fluorescent organic molecule is precipitated. After standing for half an hour, the supernatant is precipitated, n-hexane is added, ultrasonication is performed, and the reaction is allowed to stand for half an hour. The supernatant is washed three times, the solid is filtered out, and the reaction is dried to obtain a cyanostyrene borate-based siloxane fluorescent organic molecule.

7. The preparation method according to claim 2, characterized in that: The specific preparation steps of the hydrogen peroxide fluorescent nanoprobe with aggregation-induced emission effect in step (5) are as follows: dissolving hexadecyltrimethylammonium bromide and sodium hydroxide in deionized water to obtain an aqueous solution of hexadecyltrimethylammonium bromide, and then adding tetraethyl orthosilicate and a siloxane fluorescent organic molecule based on cyanostyrene borate to the aqueous solution of hexadecyltrimethylammonium bromide under stirring, and the mixed solution is stirred at 80° C. for 1 hour and then cooled to room temperature.

8. The preparation method according to claim 7, characterized in that: The molar ratio of the hexadecyltrimethylammonium bromide to sodium hydroxide is 1:2.55; the mass ratio of the tetraethyl orthosilicate to the cyanostyrene borate-based siloxane fluorescent organic molecule is 10:0.2-0.5.

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