Fluorine-containing porphyrinyl covalent organic framework as well as preparation method and application thereof

Abstract

The invention discloses a fluorine-containing porphyrinyl covalent organic framework and a preparation method and application thereof, the structure of the fluorine-containing porphyrinyl covalent organic framework is # imgabs0 #, the fluorine-containing porphyrinyl covalent organic framework is prepared through a Schiff base reaction that amino and aldehyde are subjected to condensation to remove one molecule of water to obtain C = N double bonds (imine bonds), hydrolysis is not prone to happening, and the fluorine-containing porphyrinyl covalent organic framework can be used for preparing the fluorine-containing porphyrinyl covalent organic framework. The hydrogel has excellent biocompatibility and stable chemical properties; the photosensitivity is remarkably improved, and oxygen can be efficiently loaded, so that photodynamic therapy is promoted under photoresponse, and the tumor treatment effect is improved.

Description

Technical Field

[0001] The invention relates to a fluorine-containing porphyrin-based covalent organic framework, a preparation method and application thereof, and belongs to the technical field of polymer materials and biomaterials. Background Art

[0002] In recent years, tumors have become a major health problem with an increasing incidence worldwide, posing a serious threat to human life. Hypoxia is one of the main characteristics of the tumor microenvironment. Hypoxia is widespread in tumor cells due to the imbalance between insufficient oxygen supply and abnormal oxygen consumption. Tumor hypoxia can lead to reduced oxygen tension in tumor tissues, abnormal proliferation of tumor cells, and dysfunction of angiogenesis. Severe tumor hypoxia can affect tumor treatment and reduce its efficacy. Solving the problem of tumor hypoxia is an important step in conquering tumor diseases.

[0003] In this context, nanomedicine, as an emerging treatment method, has attracted widespread attention. With its unique nanoscale effect and excellent biocompatibility, nanomedicine provides new possibilities for tumor treatment.

[0004] Covalent Organic Frameworks (COFs) are a type of porous crystalline material formed by organic molecules connected by covalent bonds. Since the COFs framework structure is formed by organic building units connected by strong covalent bonds, it is not easily attacked by chemical reagents, nor is it easily dissociated by high temperatures, and has high thermal stability. The advantages of COFs lie in their unique structural characteristics and rich functionality. They not only have a high specific surface area and porosity, and can efficiently load drug molecules, but also can achieve directional release and targeted delivery of drug molecules through precise design and control. However, existing COFs are prone to hydrolysis, resulting in a limited duration of drug efficacy. Summary of the invention

[0005] The present invention provides a fluorinated porphyrin-based covalent organic framework, a preparation method thereof and an application thereof. The fluorinated porphyrin-based covalent organic framework of the present invention can effectively alleviate tumor hypoxia and improve its tumor treatment effect under light response. During the preparation of the present invention, a solvothermal method is adopted to generate a Schiff base reaction of a C=N double bond (imine bond) by condensing an amino group with an aldehyde group to remove a molecule of water, thereby generating a fluorinated porphyrin-based covalent organic framework with an imine group-connected Schiff base COFs structure having excellent biocompatibility and stable chemical properties, good regularity, and not prone to hydrolysis.

[0006] In order to solve the above technical problems, the technical solutions adopted by the present invention are as follows:

[0007] A fluorinated porphyrin-based covalent organic framework (COFs) having the structure:

[0008]

[0009] The inventors characterized the structure and microscopic morphology of the fluorinated porphyrin-based covalent organic framework by infrared spectroscopy, ultraviolet spectroscopy, SEM, and dynamic light scattering, and determined that the fluorinated porphyrin-based covalent organic framework of the present invention is stable in nature. The material was tested for its oxygen carrying capacity, which showed excellent oxygen carrying performance, and tested for photodynamic therapy at the cellular level, indicating that it has a high application potential in the treatment of tumor hypoxia.

[0010] The fluorinated porphyrin-based covalent organic framework has high photosensitivity and high oxygen carrying capacity, and generates active oxygen after 660nm laser irradiation.

[0011] The preparation method of the fluorine-containing porphyrin-based covalent organic framework is prepared by reacting tetraaldehyde phenylporphyrin and 2,5-bis((3,3,4,4,5,5,6,6,6-nonafluorohexyl)oxy)terephthaloylhydrazide.

[0012] The tetraaldehyde phenylporphyrin and 2,5-bis((3,3,4,4,5,5,6,6,6-nonafluorohexyl)oxy)terephthaloylhydrazide used in the present application are both biocompatible materials.

[0013] In order to further improve the biocompatibility and stable chemical properties, the molar ratio of tetraaldehyde phenylporphyrin to 2,5-bis((3,3,4,4,5,5,6,6,6-nonafluorohexyl)oxy)terephthaloylhydrazide is 1:(1.8-2.2), more preferably 1:2.

[0014] The preparation method of the above-mentioned fluorinated porphyrin-based covalent organic framework has a synthetic route as follows:

[0015]

[0016] As a specific implementation scheme, the preparation method of the above-mentioned fluorinated porphyrin-based covalent organic framework is to mix tetraaldehyde phenylporphyrin and 2,5-bis((3,3,4,4,5,5,6,6,6-nonafluorohexyl)oxy)terephthaloylhydrazide, add 1,4-dioxane, chloroform and acetic acid with a concentration of 6M, ultrasonicate for 5 to 10 minutes at room temperature, degas with vacuum nitrogen, and then, seal the resulting mixture and react at 80-90°C for 2 to 4 days, cool naturally, wash with tetrahydrofuran, and vacuum dry to obtain the final product.

[0017] The concentration of the acetic acid is 6M (mol / L). The above method significantly improves the yield (synthesis rate).

[0018] The above method adopts a solvent thermal method to generate a fluorinated porphyrin-containing covalent organic framework by condensing the amino group with the aldehyde group to remove a molecule of water to obtain a Schiff base reaction of a C=N double bond (imine bond). The yield is greater than 90%.

[0019] The above-mentioned fluorinated porphyrin-based covalent organic framework has high photosensitivity and high oxygen carrying capacity, and generates active oxygen after laser irradiation, thereby promoting photodynamic therapy and improving its tumor treatment effect.

[0020] The above-mentioned 1,4-dioxane and chloroform are mainly used as reaction solvents, and acetic acid (AcOH) is mainly used as a catalyst.

[0021] The vacuum nitrogen degassing, i.e., degassing with nitrogen protection, allows the reaction to proceed under a nitrogen atmosphere.

[0022] In order to improve the reaction efficiency, the volume ratio of 1,4-dioxane, chloroform and acetic acid is 7:3:1.

[0023] In order to better ensure the formation of the final product, the vacuum drying temperature is 80-90°C and the time is 4-6h.

[0024] The fluorinated porphyrin-based covalent organic framework is used to prepare targeted drugs for killing cancer cells.

[0025] The fluorinated porphyrin-based covalent organic frameworks (COFs) prepared by the above method have fluorinated porphyrin groups, which are beneficial to improving photosensitivity and efficiently loading oxygen, thereby promoting photodynamic therapy under light response and improving its tumor treatment effect.

[0026] The above-mentioned fluorinated porphyrin-based covalent organic framework is preferably used to prepare a targeted drug for killing breast cancer cells.

[0027] The technologies not mentioned in the present invention are all referred to the prior art.

[0028] The fluorinated porphyrin-based covalent organic framework of the present invention is prepared by a Schiff base reaction in which an amino group and an aldehyde group are condensed to remove a molecule of water to obtain a C=N double bond (imine bond). It is not easy to be hydrolyzed, has excellent biocompatibility and stable chemical properties, and significantly improves the drug utilization rate; it significantly improves the photosensitivity, generates active oxygen under infrared light irradiation, and improves the efficacy of tumor treatment; it can efficiently load oxygen and deliver oxygen to hypoxic tumor sites, thereby increasing the content of active oxygen in tumor treatment, thereby promoting photodynamic therapy under light response and improving its tumor treatment effect; it has good biocompatibility and stable chemical properties; it is simple to prepare and has a high yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Infrared spectra of the fluorinated porphyrin-based covalent organic frameworks (COFs) of the present invention;

[0030] Figure 2 The UV spectrum of the fluorinated porphyrin-based covalent organic framework (COFs) of the present invention;

[0031] Figure 3 The morphology of the fluorinated porphyrin-based covalent organic framework (COFs) of the present invention is shown in a scanning electron microscope image;

[0032] Figure 4 Transmission electron microscopy images of the fluorinated porphyrin-based covalent organic frameworks (COFs) of the present invention;

[0033] Figure 5 EDS images of the fluorinated porphyrin-based covalent organic frameworks (COFs) of the present invention;

[0034] Figure 6 Particle size distribution of the fluorinated porphyrin-based covalent organic frameworks (COFs) of the present invention;

[0035] Figure 7 Oxygen loading diagram of the fluorinated porphyrin-based covalent organic frameworks (COFs) of the present invention;

[0036] Figure 8 Cell viability graph of the fluorinated porphyrin-based covalent organic frameworks (COFs) of the present invention;

[0037] Fig. 9 The active oxygen generation diagram of the fluorinated porphyrin-based covalent organic frameworks (COFs) of the present invention;

[0038] Fig.10 The effect diagram of the fluorinated porphyrin-based covalent organic framework loaded with oxygen for tumor treatment under 660nm laser irradiation;

[0039] Fig.11 The fluorinated porphyrin-based covalent organic framework of the present invention generates reactive oxygen species (ROS) after laser irradiation. DETAILED DESCRIPTION

[0040] In order to better understand the present invention, the content of the present invention is further explained below in conjunction with the embodiments, but the content of the present invention is not limited to the following embodiments.

[0041] In each case, the room temperature was 15-25° C. The stirring speed, unless otherwise specified, was 60 rpm.

[0042] Example 1

[0043] Preparation of Fluorinated Porphyrin-Based Covalent Organic Frameworks:

[0044] Weigh 14.53 mg (0.02 mmol) of tetraaldehyde phenylporphyrin (TFPP) and 28.7 mg (0.04 mmol) of 2,5-bis((3,3,4,4,5,5,6,6,6-nonafluorohexyl)oxy)terephthaloylhydrazide (TH-F9), add them into a Pyrex tube, then add 0.7 ml of 1,4-dioxane and 0.3 ml of chloroform as reaction solvents, then add 0.1 ml of 6 M acetic acid (AcOH) into the solution as a catalyst, seal the tube with raw tape, and place the solution in an ultrasonic cleaner for ultrasonic (200 W) treatment for 30 minutes to make the monomers evenly distributed in the solvent. After the ultrasonication, a purple suspension was obtained. After freezing with liquid nitrogen for 3 minutes, the sealing film was removed and the Pyrex tube was connected to the vacuum tube. After three cycles of liquid nitrogen freezing-vacuuming-nitrogen filling to remove the air in the reaction system, the system was vacuumed again for 3-5 minutes. Finally, the tube mouth was sealed under a vacuum environment, and the Pyrex tube was sealed with an 80°C flame. After the temperature rose to room temperature, it was placed in a constant temperature oven at 80-90°C for reaction for 96 hours.

[0045] After the reaction is completed, cool to room temperature, break the Pyrex tube with tweezers in a fume hood, transfer the sample inside to a 10 ml container bottle with a spoon, add 10 ml of tetrahydrofuran to soak, and replace the tetrahydrofuran every 24 hours until the upper liquid is clear to obtain a soaking solution mixed with the product.

[0046] Install the sand core funnel, connect the suction pump, put a piece of filter paper on the sand core funnel, press it with the funnel bottle, turn on the suction pump, and use a straw to absorb 1ml of tetrahydrofuran to soak the filter paper. Shake the soaking solution mixed with the product to distribute the product in the solution, then pour it into the sand core funnel for suction filtration, and use tetrahydrofuran to wash off the product stuck on the funnel wall in time, and filter for 6 minutes. After completion, use a spoon to scrape the product on the filter paper and transfer it to a 25ml solvent bottle, cover the bottle stopper, plug the side branch port with cotton, put the 25ml solvent bottle together with the heating module on the heater, and vacuum dry it at 100℃ for 4 hours. After the solvent bottle has cooled down, pour it into a mortar and grind it, pick out the glass slag, grind the sample again until the particle size is less than 100 mesh, then move it out onto a weighing paper for weighing, record the weight, and obtain a fluorinated porphyrin-based covalent organic framework (synthesis rate 91%). Finally, transfer it to a 5 ml EP tube (plastic centrifuge tube) and store it in a glass bottle with a silica gel desiccant away from light.

[0047] (I) IR and UV spectra of fluorinated porphyrin-based covalent organic frameworks:

[0048] The Fourier transform infrared absorption spectrum test was used to analyze and verify whether the fluorinated porphyrin-based covalent organic framework (TT-COF) was successfully synthesized. Figure 1The analysis showed that the infrared spectra of tetraaldehyde phenylporphyrin (TFPP), 2,5-bis((3,3,4,4,5,5,6,6,6-nonafluorohexyl)oxy)terephthaloylhydrazide (TH-F9) and TT-COF showed a strong peak at 3400 cm in the infrared spectrum of TT-COF. -1 The NH stretching vibration absorption peak of the amino group disappears, and the C=O stretching vibration signal of the aldehyde group is at 1700cm -1 The peak at 1676cm -1 The characteristic stretching vibration peak of C=N bond appeared at . The results showed that tetraaldehyde phenylporphyrin (TFPP) reacted with the aldehyde group and amino group in 2,5-bis((3,3,4,4,5,5,6,6,6-nonafluorohexyl)oxy)terephthaloylhydrazide (TH-F9) to generate a product connected by an imine bond, namely, porphyrin-based covalent organic framework (TT-COF) was successfully synthesized. The UV spectrum was measured as follows Figure 2 , which are the UV spectra of TH-F9, TFPP and TT-COF respectively.

[0049] (II) Morphological characterization of fluorinated porphyrin-based covalent organic frameworks:

[0050] 1 mg of the product was dissolved in 1 ml of deionized water, and dissolved by ultrasound. A drop was placed on an organic copper mesh, and its morphology was observed using a scanning electron microscope after the water evaporated. Figure 3 The morphology of the fluorinated porphyrin-based covalent organic framework is shown in the scanning electron microscope image. Figure 3 It can be seen that the size of the fluorinated porphyrin-based covalent organic framework is about 100 nm and is spherical under the microscopic view. Figure 4 Transmission electron microscopy (TEM) image of the nanoparticles shows clear lattice fringes, further demonstrating the synthesis of TT-COF materials. Figure 5 This is the EDS image of nanoparticles, from which we can see the distribution of C, O, N, and F in the material.

[0051] (III) Particle size distribution of fluorinated porphyrin-based covalent organic frameworks:

[0052] 1 mg of the product was dissolved in 1 ml of deionized water, sonicated to dissolve it, 1 ml of the supernatant was placed in a four-sided light-transmitting cuvette, and its particle size distribution was measured using a Malvern laser particle size analyzer. Figure 6 is the particle size distribution of the fluorinated porphyrin-based covalent organic framework, Figure 6 It can be seen that the particle size distribution of the fluorinated porphyrin-based covalent organic framework is consistent with the scanning electron microscopy observation.

[0053] (IV) Stability evaluation test of fluorinated porphyrin-based covalent organic frameworks:

[0054] 1 mg of the product was dissolved in 1 ml of deionized water and dissolved by ultrasound. 1 ml of the supernatant was placed in a cuvette with four sides transparent to light. The particle size distribution was measured using a Malvern laser particle size analyzer for six consecutive days. The particle size of the fluorinated porphyrin-based covalent organic framework remained relatively stable, proving that it is not easy to hydrolyze and has stable properties. Figure 7 Stability evaluation of covalent organic frameworks containing fluorinated porphyrin groups.

[0055] (V) Oxygen-carrying test of fluorinated porphyrin-based covalent organic frameworks:

[0056] 10 mg of the fluorinated porphyrin-based covalent organic framework prepared in Example 1 was dissolved in 10 ml of water, and then nitrogen was introduced for 15 minutes to remove the pre-dissolved gas in the water, and then oxygen was introduced for 15 minutes to allow the material to be fully loaded with oxygen. The oxygen concentration was measured using a portable dissolved oxygen meter, and the amount of dissolved oxygen far exceeded the amount of dissolved oxygen in the control group water. Figure 8 is the oxygen loading capacity of the fluorinated porphyrin-based covalent organic framework.

[0057] Example 2

[0058] Cell Viability:

[0059] The fluorinated porphyrin-based covalent organic framework obtained in Example 1 was prepared into a 10 mg / mL stock solution with PBS (phosphate buffered saline), and diluted to 1000 μg / mL and 100 μg / mL before use.

[0060] Experimental steps: 4T1 cells (provided by Hebei University of Technology) were cultured at 5×10 3 / mL was inoculated in a 96-well plate with a volume of 90μL per well and cultured in a CO2 incubator for 24h. After the cells adhered to the wall, 10μL of PBS solution of fluorinated porphyrin-based covalent organic framework was added to form different concentrations of fluorinated porphyrin-based covalent organic framework TT-COF. After 48h of culture, 10μL of MTT (3-(4,5-dimethylthiazole-2)-2,5-diphenyltetrazolium bromide) solution (5mg / mL) was added to each well and continued to incubate in the incubator for 4h. After pouring off the supernatant, 100μL of DMSO (dimethyl sulfoxide) was added to each well. After shaking, the absorbance value of each well was measured at 570nm with an enzyme marker. At the same time, a blank group (same volume of PBS) was set up to calculate the cell viability (Cell viability) = (OD value of the extract group / OD value of the blank group) × 100%. The results are shown as follows. Fig. 9 Without 660nm laser irradiation, the cell survival rate exceeded 98% after incubation with different concentrations of TT-COF for 24h, confirming that TT-COF has good biocompatibility. In contrast, 4T1 cells treated with TT-COF irradiated with 660nm laser showed obvious cytotoxicity. Fig. 9It can be seen that TT-COF itself is non-toxic to cells, but becomes cytotoxic after laser irradiation and can be used for targeted drug therapy; Fig. 9 TT-COF in the figure means no laser irradiation, and TT-COF+L means laser irradiation; at the same concentration in the figure, the left side is TT-COF, and the right side is TT-COF+L. At the same time, the fluoroporphyrin-based covalent organic framework TT-COF was loaded with oxygen (nitrogen was introduced and stirred for 15 minutes to remove the pre-dissolved gas in the water, and then oxygen was introduced and stirred for 15 minutes to allow the material to be fully loaded with oxygen). The above operation was carried out in two groups: 660nm laser irradiation and no 660nm laser irradiation. Fig.10 It can be seen that the fluorinated porphyrin-based covalent organic framework TT-COF loaded with oxygen is more effective in tumor treatment under 660nm laser irradiation. Fig.11 The fluorinated porphyrin-based covalent organic framework generates reactive oxygen species (ROS) after laser irradiation, which can effectively kill cancer cells.

Claims

1. A photosensitive high oxygen-loaded fluorinated porphyrin-based covalent organic framework, characterized in that: Its structure is:

2. A method for preparing a fluorinated porphyrin-based covalent organic framework according to claim 1, characterized in that: It is prepared by the reaction of tetraaldehyde phenylporphyrin and 2,5-bis((3,3,4,4,5,5,6,6,6-nonafluorohexyl)oxy)terephthaloylhydrazide.

3. The method for preparing a fluorinated porphyrin-based covalent organic framework according to claim 2, wherein: The molar ratio of tetraaldehyde phenylporphyrin to 2,5-bis((3,3,4,4,5,5,6,6,6-nonafluorohexyl)oxy)terephthaloylhydrazide is 1:(1.8-2.2).

4. The method for preparing a fluorinated porphyrin-based covalent organic framework according to claim 2 or 3, characterized in that: The synthesis path is:

5. The method for preparing a fluorinated porphyrin-based covalent organic framework according to claim 2 or 3, characterized in that: Tetraaldehyde phenylporphyrin and 2,5-bis((3,3,4,4,5,5,6,6,6-nonafluorohexyl)oxy)terephthaloylhydrazide are mixed, 1,4-dioxane, chloroform and acetic acid are added, ultrasonication is performed at room temperature for 5 to 10 minutes, and vacuum nitrogen is degassed. Then, the resulting mixture is sealed and reacted at 80 to 90° C. for 2 to 4 days, naturally cooled, washed with tetrahydrofuran, and vacuum dried to obtain a fluorinated porphyrin-based covalent organic framework.

6. The method for preparing a fluorinated porphyrin-based covalent organic framework according to claim 2 or 3, characterized in that: The volume ratio of 1,4-dioxane, chloroform and acetic acid is 7:3:

1.

7. The method for preparing a fluorinated porphyrin-based covalent organic framework according to claim 2 or 3, characterized in that: The vacuum drying temperature is 80-90°C and the time is 4-6h.

8. An application of the fluorinated porphyrin-based covalent organic framework according to claim 1, characterized in that: Used to prepare targeted drugs to kill cancer cells.

9. The use of the fluorinated porphyrin-based covalent organic framework as claimed in claim 8, characterized in that: Used to carry oxygen.

10. Use of the fluorinated porphyrin-based covalent organic framework according to claim 8 or 9, characterized in that: After the fluorinated porphyrin-based covalent organic framework carries oxygen, it acts as a targeted drug to kill cancer cells and produces reactive oxygen species after 660nm laser irradiation.

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