Hierarchical pore hydrogen bond organic framework material as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of synthesis of porous materials, and particularly relates to a hierarchical pore hydrogen bond organic framework material, a preparation method thereof and research and application of photoelectric detection viruses. According to the invention, tetracarboxylic acid monomer molecules forming the hydrogen bond organic framework material are synthesized by organic chemical methods such as Suzuki coupling reaction and the like, and are structurally characterized in that four benzoic acid derivatives symmetrically extend outwards by taking a pyrene ring as a center; the hydrogen bond organic framework material is formed by self-assembling tetracarboxylic acid monomer molecules through a hard template method; the hydrogen bond organic framework material has large pore size, high specific surface area and excellent thermal stability and chemical stability; the hydrogen bond organic framework material can be loaded on an electrode through a dispensing method so as to determine a photoelectric signal of the electrode.

Description

Technical Field

[0001] The present invention belongs to the technical field of porous materials, and particularly relates to a hierarchical pore hydrogen-bonded organic framework material, a preparation method thereof, and an application thereof. Background Art

[0002] Safety problems caused by biological factors have been a major challenge faced by humans for a long time. In recent years, major countries in the world have successively formulated biosafety strategies, and China has also gradually strengthened its emphasis on biosafety construction. Biosafety issues mainly include threats such as newly emerging and sudden infectious diseases, misuses of biotechnology, the safety of human genetic resources, and the invasion of alien organisms. Among them, sudden infectious diseases are the earliest ones that humans have come into contact with and are also one of the main contents of current biosafety. Infectious disease pathogens include bacteria, viruses, rickettsiae, fungi, and parasites, etc. When dealing with public health emergencies involving infectious diseases, early diagnosis and early treatment are important ways to cure sudden infectious diseases. However, the pathogen content in the initial stage of positive patients is extremely low, and the early diagnosis of viruses remains a worldwide scientific and technological problem. Therefore, developing new sensing materials and detection technologies for trace pathogenic pathogens to achieve rapid, sensitive, and accurate screening and identification of pathogens has important scientific significance and application value.

[0003] Hydrogen-bonded organic framework materials are a new type of porous materials self-assembled by organic molecules through intermolecular hydrogen bonding. This material can be prepared under mild conditions and has the advantages of structural predictability, high specific surface area, good processability of materials, and renewability. Hydrogen-bonded organic framework materials can be widely used in gas storage and separation, chiral separation, chemical sensing, proton conduction, catalysis, and many other aspects. At the same time, since the porous material does not contain metals, it has good biocompatibility and has potential application value in drug loading and biological applications. As the main force constituting the hydrogen-bonded organic framework material, the bond energy of hydrogen bond is relatively small compared with coordination bond and covalent bond, resulting in poor structural stability and greatly limiting the application scope of such materials. Selecting tetracarboxylic acids with large conjugated aromatic structures as monomers and using the hard template method can construct hierarchical pore hydrogen-bonded organic framework materials. This method can form a special structure of macropores - mesopores - micropores, which has a pre-concentration effect on biological aerosols of specific sizes and can effectively improve the ability of hydrogen-bonded organic framework materials to detect viruses by photoelectricity.

[0004] After monomers are connected through complementary hydrogen bonds to form a lamellar structure with pores, the lamellae can form a two-dimensional hydrogen-bonded organic framework material with straight pores through "shape-matching" π-π stacking interactions. This stacking method can effectively improve the stability of the mesoporous hydrogen-bonded organic framework structure. At the same time, due to the inert reactivity of the rigid molecular structure and the high tolerance to solvents, acids, and bases, the chemical stability of the hydrogen-bonded organic framework material can be effectively improved. The present invention develops a hierarchical porous hydrogen-bonded organic framework material and uses it for optoelectronic detection of viruses. Summary of the Invention

[0005] The purpose of the present invention is to provide a hierarchical porous hydrogen-bonded organic framework material with ultra-high stability, its preparation method and application to fill the gaps in the existing technology.

[0006] The hierarchical porous hydrogen-bonded organic framework material provided by the present invention is obtained by self-assembly of tetracarboxylic acid monomer molecules with a pyrene ring as the structural center and symmetrically extending four benzoic acid derivatives outward through the hard template method; specifically, a hard template is pre-synthesized, and the tetracarboxylic acid monomer molecules are connected through complementary hydrogen bonds to form a pore structure with macropores-mesopores-micropores; the hard template is removed to obtain a hierarchical porous hydrogen-bonded organic framework material with a macropore-mesopore-micropore structure; the molecular formula of the tetracarboxylic acid monomer molecule is H4TBAPy, denoted as HOF-101, and its structural formula is:

[0007]

[0008] The hierarchical porous hydrogen-bonded organic framework material provided by the present invention, under white light excitation, generates corresponding electrical signals through changes in the optoelectrochemical structure, and the electrical signals are measured in real time using a three-electrode system to detect viruses of specific sizes.

[0009] In the present invention, first, a preparation method of the tetracarboxylic acid monomer molecule constituting the hierarchical porous hydrogen-bonded organic framework material is provided, and its synthesis route is shown in the following formula:

[0010]

[0011] The specific preparation steps are as follows:

[0012] (1) React a 2-substituted p-bromobenzoic acid derivative with an equivalent amount of oxalyl chloride in dichloromethane at 0-20 °C to form a benzoyl chloride derivative, and then react it with an equivalent amount of potassium tert-butoxide in tetrahydrofuran to form a tert-butyl benzoate derivative, denoted as compound (1);

[0013] (2) In the presence of 10 equivalents of potassium acetate, 1 equivalent of 1,3,6,8-tetrakis(pinacolato)pyrene and 6 equivalents of compound (1) are heated and reacted in a dioxane / water mixed solvent with 5-10% molar fraction of dichlorobis[1,1'-bis(diphenylphosphino)ferrocene]palladium(II) as a catalyst to form intermediate compound (2);

[0014] (3) Intermediate compound (2) reacts with 5 equivalents of trifluoroacetic acid in dry dichloromethane at room temperature, or reacts with an excess of tin powder in a 20% hydrochloric acid ethanol solution to form the target product tetracarboxylic acid monomer molecule, that is, compound (3).

[0015] The preparation method of the hierarchical porous hydrogen-bonded organic framework material provided by the present invention specifically comprises the following steps:

[0016] (1) First, a polystyrene microsphere template is pre-assembled on the interface by the natural evaporation method or the electrochemical deposition method;

[0017] (2) On the interface with the existing polystyrene microsphere template, a solution containing HOF-101 is added, and the microsphere template is fully contacted with the solution to avoid the generation of bubbles;

[0018] (3) At room temperature and normal pressure, the above system is allowed to naturally volatilize to complete the rapid crystallization of HOF-101 on the template surface and simultaneously fill the voids between the templates;

[0019] (4) After the system is stable, tetrahydrofuran is added, and the polystyrene microsphere template is removed by chemical etching to obtain a hierarchical porous hydrogen-bonded organic framework material, denoted as IO HOF-101.

[0020] Furthermore, in step (l):

[0021] (a) The natural evaporation method for pre-assembling the polystyrene microsphere template is specifically as follows: The electrode is treated under an ultraviolet cleaning lamp for 5-20 minutes, a certain amount of polystyrene microsphere colloidal suspension (mass fraction 1-5%) is drop-coated on the electrode surface, and it is placed at room temperature for 1-4 h. The suspension gradually dries to form a polystyrene microsphere template, and it is dried at 50-150 °C for 1-3 hours to cure the template;

[0022] (b) The polystyrene microsphere template is pre-assembled by the electrochemically deposition method, specifically as follows: indium tin oxide conductive glass (ITO) is used as the anode, and a stainless steel plate is used as the cathode. After cleaning with acetone, deionized water, and ethanol, the electrodes are immersed in a colloidal suspension of polystyrene microspheres (mass fraction 1-5%), and the distance between the anode and the cathode is 1-5 cm. Subsequently, a DC constant voltage of 3-6 V is applied to the two electrodes for 10-60 minutes, and the polystyrene microspheres are gradually deposited on the anode. The anode ITO is taken out of the suspension, dried at 50-200 °C for 1-3 hours, and the template is solidified.

[0023] The present invention also provides the application of the above-mentioned hierarchical pore hydrogen-bonded organic framework material in the photoelectric detection of viruses. Specifically:

[0024] The hierarchical pore hydrogen-bonded organic framework material is loaded onto a screen-printed electrode, and white light is used for excitation. The corresponding electrical signals are measured through a three-electrode system. The specific steps are as follows:

[0025] (1) The excitation light source is a white light LED lamp (5W). The light source is guided to the electrode surface through an 8.0 mm optical fiber, and its light intensity is measured to be 180 mW / cm 2 ;

[0026] (2) The photoelectric measurement uses a three-electrode working system. A screen-printed electrode is used for testing. The working electrode and the counter electrode are carbon electrodes, and the reference electrode is a silver electrode. The three electrodes are encapsulated in the screen-printed electrode;

[0027] (3) The electrochemical tests are all completed on an electrochemical workstation. The photocurrent test environment is a phosphate buffer solution of ascorbic acid (0.1 mol L-1, pH 7.4), and the initial voltage is 0 V;

[0028] (4) The alternating current electrochemical impedance test environment is a KCl solution (0.5-2 mol / L) containing K3[Fe(CN)6] / K4[Fe(CN)6] (2-10 mmol / L, 1:1);

[0029] (5) The frequency is controlled in the range of 0.1 Hz to 100 kHz, the amplitude is 2-15 mV, and the initial potential is 1-2 V.

[0030] In the present invention, the hierarchical pore hydrogen-bonded organic framework structure has a macropore-mesopore-micropore structure. By using the size sieving effect, specific-sized biological viruses can be pre-concentrated. The hierarchical pore hydrogen-bonded organic framework structure contains a large number of rigid conjugated molecular structures, which can generate special electrical signals under light illumination. The hydrogen-bonded organic framework material is composed of organic molecules and has good processability. It can be loaded onto the electrode by a simple drop-coating method, greatly improving its practical value. Description of the Drawings

[0031] Figure 1 SEM scanning electron microscope image of the polystyrene microspheres prepared by the natural evaporation method in Example 1.

[0032] Figure 2 SEM scanning electron microscope image of the hierarchical pore hydrogen-bonded organic framework material in Example 1.

[0033] Figure 3 Cryo-transmission electron microscope image of the hierarchical pore hydrogen-bonded organic framework material in Example 1.

[0034] Figure 4 Lattice fringes of the hierarchical pore hydrogen-bonded organic framework material in Example 1.

[0035] Figure 5 Powder X-ray diffraction pattern of the hierarchical pore hydrogen-bonded organic framework material in Example 1.

[0036] Figure 6 Nitrogen adsorption isotherm of the hierarchical pore hydrogen-bonded organic framework material in Example 1.

[0037] Figure 7 Preparation process diagram of the hierarchical pore hydrogen-bonded organic framework material in Example 1.

[0038] Figure 8 Linear calibration curve of the hierarchical pore hydrogen-bonded organic framework material in Example 1 against HBV virus.

[0039] Figure 9 Photocurrent response signal of the hierarchical pore hydrogen-bonded organic framework material in Example 1 to white light.

[0040] Figure 10 Effect diagram of the hierarchical pore hydrogen-bonded organic framework material in Example 1 for screening viruses.

[0041] Figure 11 SEM scanning electron microscope image of the polystyrene microspheres prepared by the natural evaporation method in Example 2. Detailed implementation manners

[0042] The present invention will be further described below through specific examples in conjunction with the accompanying drawings. These examples are only used to illustrate the present invention and not to limit the scope of the present invention. In addition, it should be understood that those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the claims of this application.

[0043] Source of main reagents: All chemical reagents used were purchased from Shanghai Titan Scientific Co., Ltd.

[0044] Example 1: Preparation of polystyrene microsphere hard templates by the natural evaporation method and assembly of hierarchical pore hydrogen-bonded organic framework materials, and testing of virus detection performance.

[0045] (1) Preparation of polystyrene microsphere hard templates and assembly of hierarchical pore hydrogen bonds, see Figure 7 as shown:

[0046] Treat the electrode under an ultraviolet cleaning lamp for 5 minutes. Take a certain amount of polystyrene microsphere colloidal suspension (1.5 wt%) and drop it on the surface of the electrode. Place it at room temperature for 2 h. The suspension gradually dries to form a polystyrene microsphere template, and dry it at 100 °C for 1 hour to cure the template. The SEM scanning electron microscope image of the polystyrene microspheres is as Figure 1 shown.

[0047] Use a screen-printed electrode (denoted as SPE) instead of ITO, and construct a polystyrene microsphere template by drop-coating on the surface of the electrode. Subsequently, dissolve H4TBAPy (10 mg, 0.015 mmol) in DMF (15 mL) by ultrasonic treatment. Take 10 μL of the solution and drop it onto the template. Let it stand at room temperature for 1 hour, then remove the hard template with tetrahydrofuran, and clean the surface of the electrode with methanol, acetone and PBS solution (pH 7.4) to obtain a hierarchical pore hydrogen bond organic framework material loaded on the surface of the electrode, which is denoted as IOHOF-101 / SPE.

[0048] The SEM scanning electron microscope image of the polystyrene microspheres is as Figure 1 shown.

[0049] The SEM scanning electron microscope image of the hierarchical pore hydrogen bond organic framework material is as Figure 2 shown, the cryo-transmission electron microscope image is as Figure 3 shown, the lattice fringes are as Figure 4 shown, the powder X-ray diffraction pattern is as Figure 5 shown, and the nitrogen adsorption isotherm is as Figure 6 shown.

[0050] (2) Virus detection performance test

[0051] Utilization of a multi - pore hydrogen - bonded organic framework material for the response to viruses, specifically: A white - light LED lamp (5W) is used as the excitation light source. The light source is guided to the electrode surface through an 8.0 - mm optical fiber, and its light intensity is measured to be 180 mW / cm2. Photoelectrochemical measurement uses a three - electrode working system and a screen - printed electrode for testing. The working electrode and the counter electrode are carbon electrodes, and the reference electrode is a silver electrode. The three electrodes are encapsulated in the screen - printed electrode. Electrochemical tests are all completed on an electrochemical workstation. The photocurrent test environment is a phosphate buffer solution of ascorbic acid (0.1 mol / L, pH 7.4), and the initial voltage is 0V. The alternating - current electrochemical impedance test environment is a KCl solution (0.1 mol / L) containing K3[Fe(CN)6] / K4[Fe(CN)6] (5.0 mmol / L, 1:1). The frequency is controlled in the range of 0.1 Hz to 100 kHz, the amplitude is 5 mV, and the initial potential is 0.2V.

[0052] The linear calibration curve of the multi - pore hydrogen - bonded organic framework material for the HBV virus is as Figure 8 shown. The detected photocurrent signal shows a good linear relationship with the HBV concentration, with high precision. The photocurrent response signal of the multi - pore hydrogen - bonded organic framework material to white light is as Figure 9 shown. The detected photocurrent signal still maintains a strong signal after multiple cycles, and the signal - to - noise ratio is extremely high, which can effectively ensure the detection of the target substance.

[0053] Example 2: Preparation of a polystyrene microsphere hard template by electrochemical deposition and assembly of a multi - pore hydrogen - bonded organic framework material, as well as performance testing for virus detection.

[0054] The steps of the electrochemical deposition method are as follows: Indium tin oxide conductive glass (ITO) is used as the anode, and a stainless - steel plate is used as the cathode. After cleaning with acetone, deionized water, and ethanol, the electrodes are immersed in a polystyrene microsphere colloidal suspension (1.5 wt%). The distance between the anode and the cathode is 1.5 cm. Subsequently, a 5V DC constant voltage is applied to the two electrodes for 15 minutes, and the polystyrene microspheres are gradually deposited on the anode. The anode ITO is taken out of the suspension, dried at 100°C for 1 hour, and the template is cured to obtain a polystyrene microsphere template, similar to HOF - 101. Its SEM (scanning electron microscope) image is as Figure 11 shown.

[0055] The screen-printed electrode (denoted as SPE) was used instead of ITO, and a polystyrene microsphere template was constructed on the electrode surface by electrochemical deposition. The remaining operations were the same as those in Example 1. HOF-101 was dissolved in the MDF solvent, allowed to stand at room temperature for a period of time, then tetrahydrofuran was added to remove the hard template, and the electrode surface was washed with methanol, acetone, and PBS solution (pH 7.4) to obtain an IO HOF-101 / SPE similar to that in Example 1. It can also adopt the method in Example 1 and has the same virus detection performance.

Claims

1. A hierarchical porous hydrogen-bonded organic framework material, characterized in that, It is obtained by self-assembling tetracarboxylic acid monomer molecules with a pyrene ring as the structural center and symmetrically extending four benzoic acid derivatives outward. Specifically, a hard template is pre-synthesized, and the tetracarboxylic acid monomer molecules are connected by complementary hydrogen bonds to form a pore structure with macropores-mesopores-micropores. After removing the hard template, a hierarchical pore hydrogen-bonded organic framework material with a macropore-mesopore-micropore structure is obtained. The molecular formula of the tetracarboxylic acid monomer molecule is H4TBAPy, denoted as HOF-101, and its structural formula is:

2. A preparation method of the hierarchical porous hydrogen-bonded organic framework material as described in claim 1, characterized in that, Its synthetic route is shown as follows: The specific preparation steps are as follows: (1) Pre-assemble a polystyrene microsphere template on the interface by the natural evaporation method or the electrochemical deposition method; (2) On the interface with the existing polystyrene microsphere template, add a solution containing HOF-101, and make the microsphere template fully contact with the solution to avoid the generation of bubbles; (3) Under room temperature and atmospheric pressure conditions, let the above system naturally volatilize to complete the rapid crystallization of HOF-101 on the template surface and simultaneously fill the voids between the microspheres; (4) After the system is stable, add tetrahydrofuran, and use the chemical etching method to remove the polystyrene microsphere template to obtain a stable HOF-101 material with a hierarchical pore structure, denoted as IO HOF-101.

3. The preparation method of the hierarchical porous hydrogen-bonded organic framework material according to claim 2, wherein, In step (1): For the natural evaporation method to pre-assemble the polystyrene microsphere template, specifically: Treat the electrode under an ultraviolet cleaning lamp for 5-20 minutes, take a 1-5% mass fraction polystyrene microsphere colloidal suspension and drop it on the electrode surface, place it at room temperature for 1-4 h, the suspension gradually dries to form a polystyrene microsphere template, and dry it at 50-150 °C for 1-3 hours to cure the template; For the electrochemical deposition method to pre-assemble the polystyrene microsphere template, specifically: Use indium tin oxide conductive glass (ITO) as the anode and a stainless steel plate as the cathode. After cleaning with acetone, deionized water and ethanol, immerse the electrodes in a 1-5% mass fraction polystyrene microsphere colloidal suspension, and the distance between the anode and the cathode is 1-5 cm; Subsequently, apply a 3-6 V DC constant voltage to the two electrodes for 10-60 minutes, and the polystyrene microspheres are gradually deposited on the anode; Take out the anode ITO from the suspension and dry it at 50-200 °C for 1-3 hours to cure the template.

4. The application of the hierarchical pore hydrogen-bonded organic framework material according to claim 1 in the photoelectric detection of viruses.

5. According to the application described in claim 4, load the hierarchical pore hydrogen-bonded organic framework material onto a screen-printed electrode, use white light excitation, and test the corresponding electrical signals through a three-electrode system. The specific steps are as follows: (1) The excitation light source is a white LED lamp. The light source is guided to the electrode surface through an 8.0 mm optical fiber, and its light intensity is measured to be 180 mW / cm 2 ; (2) The photoelectric measurement uses a three-electrode working system and is tested using a screen-printed electrode. The working electrode and the counter electrode are carbon electrodes, and the reference electrode is a silver electrode. The three electrodes are encapsulated in the screen-printed electrode; (3) The electrochemical tests are all completed on an electrochemical workstation. The photocurrent test environment is a phosphate buffer solution of ascorbic acid, and the initial voltage is 0 V; (4) The test environment for alternating current electrochemical impedance is: a 0.5 - 2 mol / L KCl solution containing 2 - 10 mmol / L of K3[Fe(CN)6] / K4[Fe(CN)6]; (5) The frequency is controlled within the range of 0.1 Hz to 100 kHz, the amplitude is 2 - 15 mV, and the initial potential is 1 - 2 V.

Images