Two-color visual hydrazine fluorescent probe as well as preparation method and application thereof

Abstract

The invention discloses a two-color visual hydrazine fluorescent probe as well as a preparation method and application thereof, and belongs to the technical field of detection. According to the present invention, the ESIPT and benzo anhydride coupled imide element molecule and the derivative thereof are adopted as the two-color visual hydrazine fluorescent probe, such that the hydrazine can be efficiently and rapidly detected through the two-color visual change in the solid-liquid-gas three states, and the accurate detection of the hydrazine content in the actual sample is achieved by using the two-color visual hydrazine fluorescent probe.

Description

Technical Field

[0001] The present application relates to a dual-color visualized hydrazine fluorescent probe and a preparation method and application thereof, belonging to the field of detection technology. Background Art

[0002] Hydrazine (N2H4) is a colorless, highly reducing, corrosive and highly toxic compound with a strong ammonia smell and is easily soluble in water. As a high-energy fuel, hydrazine is used in the propulsion systems of rockets and satellites. It is also widely used as a chemical raw material in the chemical manufacturing of foaming agents, pesticides, antioxidants, polymers, etc. It is also used in water treatment. Although hydrazine has a wide range of applications, it is a known carcinogen and poses health risks and environmental hazards. It is extremely important to timely detect the concentration of hydrazine in the workplace, industrial processes and the environment to help prevent accidents. At present, there are many different methods for detecting hydrazine. Common traditional technical means such as spectroscopy, chromatography, mass spectrometry, etc. often have the problem that the sample pretreatment during the hydrazine detection process is usually cumbersome. For example, the sample matrix is ​​complex and contains a variety of interfering substances, which affects the accuracy of the detection; hydrazine is volatile and its chemical properties are unstable. Special protective measures need to be taken during the pretreatment process to prevent the volatilization or degradation of hydrazine; traditional detection methods usually rely on large instruments and equipment, such as mass spectrometers and chromatographs, and the operation is cumbersome and time-consuming.

[0003] Compared with traditional detection methods, the fluorescent probe method for detecting hydrazine hydrate has the advantages of simple operation, small error and higher sensitivity, and can also realize fluorescent imaging for refined detection of hydrazine in vivo. At present, fluorescent probes for detecting hydrazine hydrate can be roughly divided into two categories: one is fluorescent probes created from scratch ( Tetrahedron 2024, 161 , 134006.); the second is a fluorescent probe that changes fluorescence from one luminescence to another ( Chem. Eng. J. 2021, 415 , 128975.). However, these examples only have one wavelength change and cannot accurately detect hydrazine in the presence of external interference. More importantly, the current imide-based probes do not detect hydrazine in three states: solid, liquid, and gas. Therefore, a fast, efficient, and multi-wavelength detection method for hydrazine is needed. Summary of the invention

[0004] In order to solve the problem that it is difficult to detect hydrazine quickly and efficiently in the three states of solid, liquid and gas in the existing technology of detecting hydrazine by fluorescence method, the present application provides a preparation and detection method of a two-color visualized hydrazine fluorescent probe, which uses the fluorescence method to produce obvious fluorescence changes when the probe reacts with hydrazine, and changes the range of luminescence from colorless to yellow and then to blue-green during detection, thereby realizing dual-wavelength visualized fluorescence detection of hydrazine content, thereby realizing independent of instruments and equipment, more general and convenient solid phase, gas phase and liquid phase system efficient hydrazine detection.

[0005] This application adopts the following technical solutions: According to one aspect of the present application, a dual-color visualized hydrazine fluorescent probe is provided, wherein the dual-color visualized hydrazine fluorescent probe has a structure shown in Formula I: Formula I; Wherein, R1 is selected from one of N(CH3)2, OMe, CH3, H, Br, CF3, and NO2.

[0006] The dual-color visualized hydrazine fluorescent probe package in the present application is an imide-based molecule or a derivative thereof coupled with ESIPT and benzoic anhydride.

[0007] According to another aspect of the present application, a method for preparing a dual-color visualized hydrazine fluorescent probe is provided, comprising the following steps: A mixture containing benzoic anhydride, ESIPT-type materials and acetic acid is reacted to obtain the visualized hydrazine fluorescent probe.

[0008] Optionally, the benzoic anhydride is selected from at least one of the compounds of the structure shown in Formula II: Formula II; Wherein, R1 is selected from one of N(CH3)2, OMe, CH3, H, Br, CF3, and NO2.

[0009] Optionally, the ESIPT material is selected from the compound of the structure shown in Formula III: Formula III.

[0010] Optionally, the molar ratio of the benzoic anhydride and the ESIPT material is 1:1-10.

[0011] Optionally, the reaction conditions include: reaction temperature of 40-80 °C and reaction time of 4-72 h.

[0012] Optionally, after the reaction process is completed, the reaction liquid is cooled to room temperature and then extracted, dried and separated.

[0013] According to another aspect of the present application, there is also provided an application of the above-mentioned two-color visualized hydrazine fluorescent probe or the two-color visualized hydrazine fluorescent probe obtained according to the above-mentioned preparation method in hydrazine detection.

[0014] Optionally, the conditions for hydrazine detection include: hydrazine or a hydrazine-containing substance is in at least one of a solid state, a liquid state or a gaseous state.

[0015] Optionally, the application includes: contacting and reacting the dual-color visualized hydrazine fluorescent probe with hydrazine or a hydrazine-containing substance, and realizing accurate detection of the hydrazine content by acquiring the fluorescence color change and fluorescence spectrum information of hydrazine or the hydrazine-containing substance.

[0016] The beneficial effects of this application include: The dual-color visualized hydrazine fluorescent probe provided in the present application can realize efficient and rapid detection of hydrazine in three states of solid, liquid and gas through dual-color visualized changes, and can realize accurate detection of hydrazine content in actual samples by using the dual-color visualized hydrazine fluorescent probe. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is the hydrogen nuclear magnetic resonance spectrum of compound 6 in the examples of this application; Figure 2 The fluorescence spectra of the compound 6 in the test example of this application reacting with 1 equivalent and 10 equivalents of hydrazine hydrate in a mixed solvent of ethanol and water, wherein the concentration of the compound 6 is 25 μM; Figure 3 The hydrogen spectrum change of the substance in the reaction process of compound 6 and hydrazine in the liquid state in the test example of this application; Figure 4 The visualized color change of the reaction process of hydrazine with compound 6 in the vapor state in the test example of this application; Figure 5 This is the reaction process of compound 6 and hydrazine in a solid grinding state in the test example of this application, wherein Figure 5 a in the figure is the change of the visualized color. Figure 5 b in it is the fluorescence spectrum; Figure 6 This is the change in the visualized color of hydrazine in the actual sample detected by dual-color visualization in the test example of this application.

[0018] Figure 7 This is a schematic diagram of the reaction process of compound 6 in the test example of this application with hydrazine in a liquid state. DETAILED DESCRIPTION

[0019] The present application is described in detail below with reference to embodiments, but the present application is not limited to these embodiments.

[0020] Unless otherwise specified, the raw materials in the examples of this application were purchased through commercial channels.

[0021] Unless otherwise specified, conventional methods were used for testing and instrument settings were those recommended by the manufacturer.

[0022] The preparation route and product of the dual-color visualized hydrazine fluorescent probe in this application are shown in Formula-1: Formula-1; Through a one-step condensation coupling reaction, the imide compound coupled with ESIPT and benzoic anhydride, namely the dual-color visualized hydrazine fluorescent probe, can be prepared in an integrated manner. When R1 in Formula-1 takes different groups, the dual-color visualized hydrazine fluorescent probe specifically corresponds to Compounds 3 to 9.

[0023] The following preparation and testing studies were performed using compound 6 as an example: Example 1 Synthesis of dual-color visualized hydrazine fluorescent probe (Compound 6): Weigh 1 equivalent of Compound 1 and 1.2 equivalents of Compound 2 in a round-bottom flask, add 20 ml of acetic acid, 55 o C for 12 h. After the reaction solution was cooled to room temperature, it was extracted with dichloromethane three times, the organic phases were combined and dried over anhydrous sodium sulfate, the solvent was removed by rotary evaporator, and then separated by column chromatography (SiO2), and the eluent was petroleum ether: ethyl acetate = 4:1. Compound 6 was obtained as a white solid with a yield of 85%.

[0024] H NMR spectrum of compound 6: 1 H NMR (DMSO- d 6): δ = 8.08-8.06 (m, 1H), 8.03(s, 8H), 8.00-7.94 (m, 4H), 7.57 (s, 2H), 7.41-7.37 (m, 3H), 2.52 (s, 3H). See the attached for the specific spectrum. Figure 1 .

[0025] A series of other imide compounds can be obtained by the above method, and the compounds can be characterized by nuclear magnetic resonance, mass spectrometry and other means.

[0026] Test Example 1 Compound 6 was prepared into a 25 μM standard solution of ethanol and water (volume ratio of 1:10), and its fluorescence spectrum was measured. Then, 1 equivalent and 10 equivalents of hydrazine hydrate were added to the solution, respectively, and the fluorescence spectrum was measured after the reaction reached thermodynamic stability. Figure 2 As shown, when 1 equivalent of hydrazine hydrate is added, a new emission peak appears at about 570 nm. When 10 equivalents of hydrazine hydrate are added, a new emission peak appears at about 460 nm. Through the test of the excitation spectrum, it is determined that both are excited by 370 nm light to test the emission spectrum.

[0027] Test Example 2 The schematic diagram of the reaction process of compound 6 in liquid state with hydrazine is shown in Figure 7 As shown: Compound 6 was prepared into a 10.0 mM deuterated DMSO standard solution, and its hydrogen spectrum was measured. Two equivalents of hydrazine hydrate were added to the standard solution, and the reaction time was tracked. The results of its hydrogen nuclear magnetic resonance spectrum were measured as follows: Figure 3 As shown, after 10 minutes, the methyl peak of compound 6 disappears, and a group of corresponding methyl peaks belonging to compound 11 are generated; after 24 hours, the methyl peak of compound 11 disappears, and a group of corresponding methyl peaks belonging to compound 12 are generated.

[0028] Test Example 3 Compound 6 was prepared into a 10.0 mM chloroform standard solution, and then the brush was placed in the standard solution for 10 minutes. NH2NH2 was further written on the filter paper with the brush and then blown dry with a hair dryer. The prepared sample was placed on top of hydrazine hydrate, and then its fluorescence color was tracked with evaporation time. The color change was recorded by taking a photo with a mobile phone under 365 nm ultraviolet light. The results are as follows: Figure 4 As shown, when compound 6 is placed on hydrazine vapor for 1 minute, the pattern turns orange under 365 nm ultraviolet light. After another ten minutes, the pattern turns white under 365 nm ultraviolet light. After another 30 minutes, the pattern turns blue under 365 nm ultraviolet light.

[0029] Test Example 4 3 mg of compound 6 was placed in a mortar, and then 1 equivalent of hydrazine hydrate was added for grinding. After grinding for 10 minutes, a mobile phone was used to take a photo to record the visual color change, and the solid was placed under a solid fluorescence tester to record the change in its fluorescence spectrum. The result is shown in a in the figure. After adding hydrazine hydrate and grinding for 10 minutes, the solid was orange-yellow under 365 nm ultraviolet light. After adding hydrazine hydrate to compound 6, it was ground and the fluorescence spectrum was measured at different times. The results are shown in Figure 5 After adding hydrazine hydrate to b and grinding for 10 minutes, a new emission peak appears at about 600 nm in its fluorescence spectrum. After adding hydrazine hydrate and grinding for 1 hour, its emission peak in the fluorescence spectrum is blue-shifted, and the solid is blue under 365 nm ultraviolet light, accompanied by a decrease in fluorescence intensity. On this basis, 9 equivalents of hydrazine hydrate are added for grinding. After grinding for 10 minutes, the visual color change is recorded by taking a photo with a mobile phone under 365 nm ultraviolet light, and the solid is placed under a solid fluorescence tester to record the change in its fluorescence spectrum. Among them, through the test of the excitation spectrum, it is determined that both are excited by 370 nm light to test the emission spectrum.

[0030] Test Example 5 Taking compound 6 as an example, the efficacy of visual fluorescent probe 6 in detecting hydrazine in actual samples was further studied. Rice was soaked in different concentrations of hydrazine (1 mM and 10 mM) for 30 minutes, and then the solution was filtered to remove it. The rice was further dried with a hair dryer to obtain rice contaminated with hydrazine. The solution of compound 6 was then sprayed on rice contaminated with different concentrations of hydrazine, and the visual color changes were recorded by taking photos with a mobile phone under 365 nm ultraviolet light. The results are shown in Figure 2. Figure 6 As shown in the figure, after spraying the compound 6 solution, the rice contaminated with hydrazine showed obvious fluorescence signals under 365 nm ultraviolet light, and different visualization colors (from orange to blue) were shown for rice with different hydrazine contents. In contrast, no changes were observed in the rice contaminated with hydrazine or the compound 6 solution under ultraviolet light. Therefore, fluorescent probe 6 can effectively detect hydrazine in food samples.

[0031] The above are only a few embodiments of the present application and do not constitute any form of limitation to the present application. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Any technician familiar with the profession, without departing from the scope of the technical solution of the present application, using the technical content disclosed above to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A dual-color visualized hydrazine fluorescent probe, characterized in that: The dual-color visualized hydrazine fluorescent probe has a structure shown in Formula I: Formula I; Wherein, R1 is selected from one of N(CH3)2, OMe, CH3, H, Br, CF3, and NO2.

2. The method for preparing the dual-color visualized hydrazine fluorescent probe according to claim 1, characterized in that: The steps include: A mixture containing benzoic anhydride, ESIPT-type materials and acetic acid is reacted to obtain the visualized hydrazine fluorescent probe.

3. The preparation method according to claim 2, characterized in that: The benzoic anhydride is selected from at least one of the compounds of the structure shown in Formula II: Formula II; Wherein, R1 is selected from one of N(CH3)2, OMe, CH3, H, Br, CF3, and NO2.

4. The preparation method according to claim 2, characterized in that: ESIPT materials are selected from compounds of the structure shown in formula III: Formula III.

5. The preparation method according to claim 2, characterized in that: The molar ratio of the benzoic anhydride to the ESIPT material is 1:1-10.

6. The preparation method according to claim 2, characterized in that: The reaction conditions include: reaction temperature of 40-80° C., and reaction time of 4-72 h.

7. The preparation method according to claim 2, characterized in that: After the reaction process is completed, the reaction liquid is cooled to room temperature and then extracted, dried and separated.

8. Use of the dual-color visualized hydrazine fluorescent probe according to claim 1 or the dual-color visualized hydrazine fluorescent probe obtained according to the preparation method according to any one of claims 2 to 7 in hydrazine detection.

9. The use according to claim 8, characterized in that: The conditions for hydrazine detection include: hydrazine or a substance containing hydrazine is in at least one of a solid state, a liquid state or a gaseous state.

10. The use according to claim 8, characterized in that: The application includes: contacting and reacting a dual-color visualized hydrazine fluorescent probe with hydrazine or a hydrazine-containing substance, and realizing accurate detection of the hydrazine content by acquiring the fluorescence color change and fluorescence spectrum information of hydrazine or the hydrazine-containing substance.

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