Organic polymer composite material based on BODIPY light-controlled CO release as well as preparation method and application of organic polymer composite material

Abstract

The invention discloses an organic polymer composite material based on BODIPY light-controlled CO release as well as a preparation method and application thereof, and belongs to the technical field of biological medicines. The preparation method comprises the following steps: dissolving tetraaldehyde BDP and 2, 2 '-bipyridine-5, 5'-diamine in an organic solvent, carrying out ultrasonic dispersion to form a suspension, carrying out circulating deoxidation, and carrying out a heating reaction in a sealed environment to obtain a powdery black solid BB-COF; the preparation method comprises the following steps: suspending BB-COF and pentacarbonyl manganese bromide in absolute ether in a protective atmosphere, and stirring at room temperature for reaction to obtain the organic polymer composite material based on BODIPY light-controlled CO release. The composite material prepared by the invention has an egg-shell-shaped spherical structure and light-controlled CO release capability, and can resist bacteria through a quadruple synergistic mechanism of photothermal therapy, photodynamic therapy, Fenton reaction and CO release, so that the composite material has better safety when being applied to organisms.

Description

Technical Field

[0001] The present invention relates to the field of biomedical technologies, and particularly to an organic polymer composite based on BODIPY light-controlled CO release, and a preparation method and application thereof. Background Art

[0002] In the past few decades, many antibiotic-free antibacterial methods that cannot induce drug resistance have been developed as alternatives to antibiotics, such as photothermal therapy (PTT) based on thermal damage, photodynamic therapy (PDT) based on reactive oxygen species (ROS), enzyme therapy, and sonodynamic therapy (SDT). However, these technologies have been challenged by various factors in practical applications. For example, the limited oxygen concentration greatly hinders the efficiency of PDT, and PTT faces challenges in treatment specificity, etc., which will inevitably cause damage to normal tissues. To solve these problems simultaneously, achieve satisfactory treatment effects and reduce side effects, complex treatment strategies can not only exert targeted treatment effects, but also effectively reshape the pathological wound microenvironment, showing unique advantages in the treatment of infectious wounds. However, such complex therapeutic drugs still face huge challenges, including low active site density, low selectivity and specificity, etc. Therefore, there is still an urgent need to develop intelligent and efficient complex therapeutic drugs.

[0003] Phototherapy mainly consists of PDT and PTT, and has the characteristics of non-invasiveness and high efficiency. In the presence of a photosensitizer (PS), PDT generates reactive oxygen species through laser irradiation, which reacts with various biomolecules of bacteria (such as lipids in the cell membrane, proteins and nucleic acids in the cell). PTT is also generated by laser irradiation in the presence of a photosensitizer (in some cases, it can also be some materials with photothermal conversion properties); however, it mainly converts light energy into heat energy to increase the local temperature; when the temperature rises to a certain extent, it will cause irreversible damage to bacteria, such as denaturing the proteins of bacteria. The Fenton reaction is an inorganic chemical reaction. Under acidic conditions (usually the pH value is about 2-4), hydrogen peroxide (H2O2) reacts with variable-valent metals to generate highly reactive hydroxyl radicals (·OH); the generated hydroxyl radicals can destroy the cell structure of bacteria and play a good role in disinfection and sterilization. Some studies have shown that CO gas can change the fluidity and permeability of the bacterial cell membrane; it may interact with certain components on the bacterial cell membrane, such as lipids or membrane proteins, resulting in changes in the structure of the bacterial cell membrane. Moreover, compared with some chemical disinfectants, the decomposition products of CO gas after sterilization are relatively simple, mainly harmless substances such as carbon dioxide. Fluoroboron dipyrrole (BODIPY) compounds are a class of important fluorescent dyes. Due to their excellent optical properties, they have been reported to be used in photothermal therapy (PTT) and photodynamic therapy (PDT) for tumors and antibacterial purposes. However, many problems still exist in the application, such as a single substance not having multiple functions such as PTT and PDT at the same time, being unable to simultaneously excite multiple photosensitizers with a single-wavelength laser, and not clearly understanding the structure-activity relationship between BODIPY and PTT / PDT, which all hinder the further development of BODIPY in the field of phototherapy. The patent with the application number CN116785433A discloses a photothermal-photodynamic driven NO release synergistic cationic antibacterial material and its application. A porous polymer BG-POP is obtained by the dehydration condensation reaction of a fluoroboron dipyrrole compound (Bodipy) and triaminoguanidine hydrochloride; the porous polymer and sodium nitroprusside are added to water and mixed to obtain a photothermal-photodynamic driven NO release synergistic cationic antibacterial material BG-SNP. However, there is currently no composite material based on BODIPY for photocontrolled release of CO for antibacterial purposes. If it can have four antibacterial modes: photothermal, photodynamic, CO, and Fenton, it is expected to obtain a more efficient and controllable broad-spectrum bactericide. Summary of the Invention

[0004] In view of the above-mentioned prior art, the object of the present invention is to provide an organic polymer composite material based on BODIPY photocontrolled CO release, its preparation method and application. The present invention polymerizes tetraaldehyde BDP and 2,2'-bipyridine-5,5'-diamine, and uses the multidentate ligand of bipyridine to load manganese pentacarbonyl bromide to obtain an organic polymer composite material; this material has an eggshell-like spherical structure and has the ability of photocontrolled CO release, and can antibacterial through the quadruple synergistic mechanism of photothermal therapy, photodynamic therapy, Fenton reaction and carbon monoxide (CO) release, making it obtain better safety for application in organisms.

[0005] To achieve the above object, the present invention adopts the following technical solutions: In the first aspect of the present invention, a preparation method of an organic polymer composite material based on BODIPY photocontrolled CO release is provided, including the following steps: (1) BODIPY undergoes an iodination reaction with an iodine-containing compound to obtain iodinated BODIPY; (2) Dissolve iodinated BODIPY, 3,5-diformylphenylboronic acid and potassium carbonate in an organic solvent, add a catalyst under a protective atmosphere and react to obtain tetraaldehyde BDP; (3) Dissolve tetraaldehyde BDP and polyaminobipyridine in an organic solvent, ultrasonically disperse to form a suspension, after cyclic deoxidation, heat and react in a sealed environment to obtain a powdery black solid BB-COF; (4) Under a protective atmosphere, suspend BB-COF and manganese pentacarbonyl bromide in anhydrous diethyl ether, and stir and react at room temperature to obtain an organic polymer composite material based on BODIPY photocontrolled CO release.

[0006] Preferably, in step (1), the iodine-containing compound is N-iodosuccinimide; the molar ratio of BODIPY to N-iodosuccinimide is 1:2; the iodination reaction is that BODIPY and N-iodosuccinimide are dissolved in anhydrous dichloromethane and stirred at room temperature.

[0007] Preferably, in step (2), the molar ratio of iodinated BODIPY to 3,5-diformylphenylboronic acid is 1:2; the organic solvent is 1,4-dioxane; the catalyst is tetrakis(triphenylphosphine)palladium.

[0008] Preferably, in step (2), the reaction temperature is 120 °C and the reaction time is 12 h.

[0009] Preferably, in step (3), the polyaminobipyridine is 2,2'-bipyridine-5,5'-diamine; the organic solvent is a mixture of toluene and acetic acid solution in a volume ratio of 20:1; the concentration of the acetic acid solution is 3 M; the heating reaction temperature is 120 °C and the reaction time is 72 h.

[0010] Preferably, the molar ratio of the tetra-aldehyde BDP to 2,2'-bipyridine-5,5'-diamine is 1:2.

[0011] Preferably, in step (4), the molar ratio of the BB-COF to manganese pentacarbonyl bromide (Mn(CO)5Br) is 1:4; the time for stirring reaction at room temperature is 4 h.

[0012] In the second aspect of the present invention, there is provided an organic polymer composite material based on BODIPY photocontrolled CO release obtained by the above preparation method. The organic polymer composite material based on BODIPY photocontrolled CO release is polymerized with poly-aldehyde BDP and poly-amino bipyridine as monomers, and manganese pentacarbonyl bromide is loaded by using the multidentate ligand of bipyridine; the organic polymer composite material based on BODIPY photocontrolled CO release has an eggshell-like spherical structure and releases CO under laser irradiation.

[0013] Preferably, the poly-aldehyde BDP is tetra-aldehyde BDP; the poly-amino bipyridine is 2,2'-bipyridine-5,5'-diamine.

[0014] In the third aspect of the present invention, there is provided an application of the organic polymer composite material based on BODIPY photocontrolled CO release in the preparation of antibacterial drugs.

[0015] The organic polymer composite material based on BODIPY photocontrolled CO release has a synergistic antibacterial effect through four therapies: photothermal therapy, photodynamic therapy, Fenton reaction and carbon monoxide (CO) release.

[0016] Advantages of the present invention: (1) The organic polymer composite material based on BODIPY photocontrolled CO release (hereinafter referred to as BB-COF@Mn) prepared by the present invention can cause good photothermal conversion under 638 nm wavelength laser irradiation, and can also generate singlet oxygen, hydroxyl radicals and superoxide anions through the induced electron transfer. In addition, the manganese pentacarbonyl bromide loaded on the material can release carbon monoxide by photocontrol, so that BB-COF@Mn has a quadruple synergistic mechanism of photothermal therapy, photodynamic therapy, Fenton reaction and carbon monoxide (CO) release, realizing combined broad-spectrum antibacterial.

[0017] (2) The preparation method of the present invention is simple, and the prepared BB-COF@Mn has good biocompatibility, and its structure and performance are stable. The hemolysis rate on red blood cells is less than 1.5%, the viability of HEK293 cells and L929 cells is slightly affected, and it has no toxic and side effects on the human body, which will promote the development of a multifunctional antibacterial platform. Description of the Drawings

[0018] Figure 1: Characterization and analysis diagrams of BB-COF@Mn; among them, (a) is the infrared spectrum of BB-COF@Mn; (b) is the solid-state carbon spectrum of BB-COF@Mn 13 C NMR; (c) is the pore size distribution curve of BB-COF@Mn; (d) is the low-temperature N2 absorption isotherm of BB-COF@Mn at 77 K; (e) is the thermogravimetric curve of BB-COF@Mn; (f) is the particle size distribution diagram of BB-COF@Mn; Figure 2 : SEM and TEM images of BB-COF@Mn; among them, (a) is the SEM of BB-COF at a scale of 5 µm; (b) is the SEM of BB-COF at a scale of 2 µm; (c) is the SEM of BB-COF@Mn at a scale of 5 µm; (d) is the SEM of BB-COF@Mn at a scale of 2 µm; (e) is the TEM of BB-COF at a scale of 1 µm; (f) is the TEM of BB-COF at a scale of 500 nm; (g) is the TEM of BB-COF at a scale of 50 nm; (h) is the TEM of BB-COF at a scale of 10 nm; (i) is the TEM of BB-COF@Mn at a scale of 1 µm; (j) is the TEM of BB-COF@Mn at a scale of 500 nm; (k) is the TEM of BB-COF@Mn at a scale of 50 nm; (l) is the TEM of BB-COF@Mn at a scale of 10 nm; (m) is the mapping image of BB-COF@Mn; (n) is the distribution of B element in BB-COF@Mn; (o) is the distribution of C element in BB-COF@Mn; (p) is the distribution of N element in BB-COF@Mn; (q) is the distribution of O element in BB-COF@Mn; (r) is the distribution of F element in BB-COF@Mn; (s) is the distribution of Mn element in BB-COF@Mn; (t) is the distribution of Br element in BB-COF@Mn; Figure 3 : EDS diagrams of BB-COF@Mn; Figure 4 : Photothermal properties of BB-COF@Mn; among them, (a) is the concentration-dependent photothermal effect of BB-COF@Mn under 638 nm laser irradiation at 1.5 W / cm 2 ; (b) is the laser power-dependent photothermal effect of BB-COF@Mn under 638 nm laser irradiation at 0.3, 0.7, 1.0, 1.3, and 1.5 W / cm 2 respectively; (c) is the thermal imaging pictures of the heating process of different concentrations of BB-COF@Mn within 15 min; Figure 5: Photothermal stability of BB-COF@Mn; where (a) is the temperature change curve of three cycles of light irradiation and cooling of BB-COF@Mn (200 μg / mL) under a 638 nm laser at 1.5 W / cm 2 ; (b) is the temperature change curve of a continuous heating-cooling process of the aqueous dispersion of BB-COF@Mn (200 μg / mL) by controlling the on-off of a 638 nm laser (1.5 W / cm 2 ); (c) is the curve of the negative natural logarithm of the ratio of the difference between the temperature at each moment and the corresponding temperature and the ambient temperature to the difference between the highest temperature and the ambient temperature during the cooling cycle of BB-COF@Mn; Figure 6 : Electron paramagnetic resonance spectrum of BB-COF@Mn; Figure 7 : Photodynamic performance of BB-COF@Mn, where (a) is the ultraviolet-visible spectrum of DPBF under red light (638 nm, 1.5 W / cm 2 ) irradiation; (b) is the ultraviolet-visible spectrum of DPBF + B-COF@Mn under red light (638 nm, 1.5 W / cm 2 ) irradiation; Figure 8 : Light-controlled CO release ability and Fenton reaction of BB-COF@Mn; where (a) is the ultraviolet-visible spectra of Deoxy-Mb and BB-COF@Mn; (b) is the ultraviolet-visible spectra of Deoxy-Mb and BB-COF@Mn under 638 nm laser irradiation; (c) is the ultraviolet-visible spectra of four groups (A: TMB, B: TMB + H2O2, C: TMB + H2O2 + BB-COF, D: TMB + H2O2 + BB-COF@Mn); (d) is the ultraviolet-visible spectra of different concentrations of BB-COF@Mn (50, 100, 125, 150, and 200 μg / mL) + TMB + H2O2, experimental conditions: 1.5 mmol / L TMB, 20 mmol / L hydrogen peroxide, triggered in an aqueous environment at pH = 4.5; Figure 9 : Antibacterial ability of different concentrations of BB-COF@Mn; where (a) is the culture images of Staphylococcus aureus and Escherichia coli after treatment with different concentrations of BB-COF@Mn; (b) is the statistical chart of the bacterial survival rate of Staphylococcus aureus and Escherichia coli determined by the plate counting method; Figure 10 : Antibacterial ability under different treatment methods; where (a) is the culture images of Staphylococcus aureus and Escherichia coli after different treatment methods; (b) is the statistical chart of the bacterial survival rate of Staphylococcus aureus and Escherichia coli determined by the plate counting method; Figure 11:Transmission electron micrographs of Staphylococcus aureus and Escherichia coli under different treatment methods, with a scale bar of 2.0 μm; Figure 12 :Biocompatibility experiment of BB-COF@Mn; among them, (a) is the hemolysis rate of BB-COF@Mn at different concentrations; (b) is the cell viability after incubation of BB-COF@Mn at different concentrations with L929 cells or HEK293 cells. Detailed implementation manners

[0019] It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs.

[0020] As introduced in the background art section, there are currently reports on the use of BODIPY for photothermal therapy (PTT) and photodynamic therapy (PDT) of tumors and antibacterial. However, there are still many problems in the application, such as a single substance not having multiple functions such as PTT and PDT at the same time, being unable to simultaneously excite multiple photosensitizers with a single-wavelength laser, and not clearly understanding the structure-activity relationship between BODIPY and PTT / PDT, which all hinder the further development of BODIPY in the field of phototherapy. There is a need to develop a multi-mode synergistic antibacterial material based on BODIPY.

[0021] Based on this, the purpose of the present invention is to provide an organic polymer composite material based on BODIPY photocontrolled CO release, its preparation method and application. The present invention first prepares tetraaldehyde BODIPY, namely tetraaldehyde BDP, by iodination reaction and suzuki coupling of BODIPY; tetraaldehyde BDP is then polymerized with polyaminobipyridine (2,2'-bipyridine-5,5'-diamine) to obtain BB-COF. BB-COF only has two antibacterial modes of photothermal and photodynamic, so the multidentate ligand of bipyridine on BB-COF is used to combine with Mn(CO)5Br to obtain BB-COF@Mn. Mn(CO)5Br in BB-COF@Mn can release CO under infrared light irradiation, and Mn has a Fenton effect, so that BB-COF@Mn has four antibacterial modes of photothermal therapy, photodynamic therapy, Fenton reaction and carbon monoxide (CO) release. In addition, the BB-COF@Mn prepared by the present invention has an eggshell-like spherical structure, which is beneficial to drug loading and can provide an excellent carrier for the development of PTT / PDT anti-tumor drugs in the future.

[0022] In order to enable those skilled in the art to more clearly understand the technical solution of the present application, the technical solution of the present application will be described in detail below in conjunction with specific embodiments.

[0023] The test materials used in the embodiments of the present invention are all conventional test materials in the art and can be obtained through commercial channels.

[0024] Example 1 Preparation of BB-COF@Mn (1)Preparation of BODIPY: Under nitrogen protection, freshly distilled benzaldehyde (2.1 mL, 20 mmol) and 2,4-dimethylpyrrole (5 mL, 48 mmol) were dissolved in dry dichloromethane (80 mL), and trifluoroacetic acid (TFA, 3 drops) was added dropwise. Subsequently, 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ, 5.54 g, 20 mmol) was added. After stirring at room temperature for 10 minutes, triethylamine (20 mL) and boron trifluoride-ether complex (BF3·OEt2, 20 mL) were slowly added in sequence, and stirring was continued for 1 hour. The reaction solution was quenched with water and extracted three times with dichloromethane. The combined organic phases were washed with saturated brine, dried over anhydrous sodium sulfate, concentrated under reduced pressure, and purified by column chromatography (silica gel, volume ratio of petroleum ether to ethyl acetate = 10:1) to obtain a dark red solid BODIPY.

[0025] 。

[0026] (2)Preparation of iodinated BODIPY (Diiodo-BDP): BODIPY (200 mg, 0.31 mmol) and an excess of N-iodosuccinimide (140 mg, 0.62 mmol) were dissolved in anhydrous dichloromethane (15 mL), and stirred at room temperature for 30 minutes. After the reaction was completed, the reaction solution was extracted three times with dichloromethane, and the combined organic phases were concentrated under reduced pressure and purified by column chromatography (silica gel, volume ratio of dichloromethane to petroleum ether = 2:1) to obtain a dark red solid Diiodo-BDP. The synthetic route is as follows: 。

[0027] (3)Preparation of tetraformyl BDP: Diiodo-BDP (85.0 mg, 0.148 mmol), 3,5-diformylphenylboronic acid (52.7 mg, 0.296 mmol) and potassium carbonate (40.9 mg, 0.296 mmol) were dissolved in anhydrous 1,4-dioxane (15 mL). Under argon protection, tetrakis(triphenylphosphine)palladium (12.0 mg, 0.296 mmol) was added, and the mixture was stirred at 120 °C for 12 hours. Then it was extracted with dichloromethane, concentrated under reduced pressure, and purified by column chromatography (silica gel, volume ratio of dichloromethane to ethyl acetate = 10:1) to obtain a red solid tetraformyl BDP. The synthetic route is as follows: 。

[0028] (4) Preparation of BB-COF: Dissolve tetraaldehyde BDP (29.4 mg, 0.05 mmol) and 2,2'-bipyridine-5,5'-diamine (18.6 mg, 0.1 mmol) in toluene (4 mL) and 3 M acetic acid solution (0.2 mL), and disperse them by ultrasonic (power 100 w) for 10 minutes to form a uniform suspension. After three freeze-pump-thaw cycles for deoxygenation, seal the pressure-resistant glass tube and react at 120 °C for 72 hours to form a brown precipitate. The product was washed three times with deionized water, methanol, ethanol, tetrahydrofuran, acetone and dichloromethane respectively, and vacuum dried at 60 °C for 8 hours to obtain a powdery black solid BB-COF. The synthetic route is as follows: 。

[0029] (5) Preparation of BB-COF@Mn: Under argon protection, suspend BB-COF (34.72 mg, 0.05 mmol) and manganese pentacarbonyl bromide (Mn(CO)5Br, 55.2 mg, 0.2 mmol) in anhydrous ether (20 mL), and stir at room temperature for 4 hours. Filter and collect the precipitate, wash it with anhydrous ether, and vacuum dry it at 60 °C for 8 hours to obtain the material BB-COF@Mn loaded with manganese pentacarbonyl bromide. The synthetic route is as follows: 。

[0030] Example 2: Characterization (1) Figure 1 (a) is the infrared spectrum of BB-COF@Mn, verifying the successful construction of BB-COF@Mn. From the Fourier transform infrared spectrum of BB-COF@Mn, strong peak signals belonging to the newly formed C=N bond (1603 cm -1 ) can be observed simultaneously. In addition, the N-H stretching vibration peaks belonging to 2,2'-bipyridine-5,5'-diamine disappear at 3205 cm -1 and 3332 cm -1 , and at the same time, the characteristic stretching band of C=O of 3,5-diformylphenylboronic acid (1704 cm -1 ) is greatly weakened, indicating that the free aldehyde is exhausted after polymerization. All these results imply the successful synthesis of the COF framework. In addition, it can also be found that the characteristic vibrations of the ketone carbonyl belonging to Mn(CO)5Br have two prominent strong infrared absorption peaks at 2065 cm -1 and 1988 cm -1 , showing obvious typical carbonyl characteristic peaks, which also proves the successful introduction of Mn(CO)5Br into BB-COF@Mn.

[0031] (2) Figure 1(b) is the solid-state carbon spectrum of BB-COF@Mn, which is further confirmed by solid-state 13 C - NMR for the framework structure of BB-COF@Mn. The methyl signal of the pyrrole ring at 12.52 ppm, the aromatic carbon peaks at 129.64 - 135.49 ppm, and the characteristic peak of the imine bond at 151.9 ppm can be observed simultaneously to form the framework core signals, while the new peaks at 57.57 ppm and 65.48 ppm are due to the coordination of Mn(CO)5Br. These results together demonstrate the successful synthesis of BB-COF@Mn.

[0032] (3) Figure 1 (c) shows the pore size distribution curve plotted according to the non-local density functional theory (NLDFT) model, and the porosity can be visually observed. It can be seen that BB-COF@Mn shows a wide PSD from 0 nm to 40 nm, and the main pore size is distributed at 1.5454 nm. After calculation, the BET surface area of BB-COF@Mn is 195.51 m 2 g -1 , and the total pore volume is 0.1459 cm 3 g -1 . Figure 1 (d) is the low-temperature N2 adsorption isotherm of BB-COF@Mn at 77 K, and the porosity characteristics of the synthesized material BB-COF@Mn are measured by low-temperature nitrogen adsorption. BB-COF@Mn shows a typical curve, conforming to the characteristics of type III adsorption isotherm, that is, the adsorption amount increases slowly at the low-pressure stage, and as the pressure increases, the adsorption amount gradually increases, but the slope of the curve is always positive, indicating that its pore structure is mainly composed of micropores.

[0033] (4) Figure 1 (e) is the thermogravimetric curve of BB-COF and BB-COF@Mn, and the thermogravimetric analysis shows the thermal stability of BB-COF@Mn. When comparing the thermogravimetric analysis of BB-COF and BB-COF@Mn, it can be clearly seen that before the temperature reaches 100 °C, due to the volatilization of strongly adsorbed water in the porous framework and the release of CO from the loaded Mn(CO)5Br, the material loss rate of BB-COF@Mn is significantly higher. However, after the release of CO, the stability of the BB-COF@Mn structure is improved compared to BB-COF, and the material loss rate also decreases.

[0034] (5) Figure 1 (f) is the particle size analysis diagram of BB-COF@Mn. The results show that the particle size of BB-COF@Mn is concentrated in the range of 900 nm to 1500 nm (accounting for 90% of the total), showing an overall normal distribution, indicating that the particle size of BB-COF@Mn is relatively stable.

[0035] (6) From Figure 2 (a) to Figure 2 (l), it can be seen that the prepared BB-COF@Mn has an eggshell-like spherical structure, and the lattice fringes are clearly distinguishable. The difference in light and dark contrast confirms its highly ordered crystal arrangement. In addition, there are abundant microporous structures inside BB-COF@Mn. TEM comparative analysis shows that the loading of Mn(CO)5Br significantly changes the surface morphology of the material. According to Figure 2 (e) to Figure 2 (h), it can be seen that the surface of BB-COF without loaded Mn(CO)5Br is smooth, while Figure 2 (i) to Figure 2 (l) shows that the surface of BB-COF@Mn presents uniformly distributed rough textures, indicating the successful anchoring of manganese pentacarbonyl bromide.

[0036] (7) Figure 2 (m) - Figure 2 (t) are the transmission electron microscopy mapping diagrams of BB-COF@Mn and the distribution of elements such as C, N, O, etc. in BB-COF@Mn. It can be seen that C (56.78%), N (8.39%), O (8.82%), Mn (10.36%), Br (10.37%), and F (1.5%) are uniformly distributed in BB-COF@Mn, indicating a certain uniformity in the structural construction of the material. Figure 3 is the EDS diagram of BB-COF@Mn. It can be found from the X-ray energy spectrum (EDX) that elements C, N, O, Mn, Br, and F are widely present.

[0037] (8) The photothermal effect of BB-COF@Mn was measured by irradiating it with a 638 nm laser for 900 seconds. Different concentrations of BB-COF@Mn aqueous dispersions (0, 50, 100, and 200 μg / mL) were prepared with deionized water and BB-COF@Mn in a 2 mL centrifuge tube, and the final total volume of each concentration of BB-COF@Mn aqueous dispersion was 1 mL. Figure 4 (a) is the concentration-dependent photothermal effect of BB-COF@Mn under irradiation with a 638 nm laser of 1.5 W / cm 2 . When the power is 1.5 W / cm 2 , as the concentration of BB-COF@Mn increases, the temperature change caused by the temperature rise of its suspension becomes larger and larger. Figure 4 (b) is the laser power-dependent photothermal effect of BB-COF@Mn under irradiation with a 638 nm laser of 0.4, 0.7, 1.0, 1.3, and 1.5 W / cm 2 . Figure 4(c) is the thermal imaging pictures of BB-COF@Mn (0, 50, 100, and 200 μg / mL) during the heating process within 15 min. These results indicate that BB-COF@Mn has a high photothermal conversion efficiency and concentration-dependent photothermal properties.

[0038] (9) Figure 5 (a) is the temperature change curve of BB-COF@Mn (200 μg / mL) under 638 nm laser irradiation at 1.5 W / cm 2 ² for 3 times of light irradiation and cooling. The temperature change of BB-COF@Mn was recorded through the ON / OFF cycle irradiation experiment. The results show that BB-COF@MnF exhibits good photothermal stability after 3 cycles (638 nm, 1.5 W / cm 2 ²). The highest temperature of the 3 cycles can reach about 62 °C, and there is no obvious change in the rising and cooling trends of the temperature. The above results indicate that BB-COF@Mn has good photothermal effects and photothermal stability, making it a potential photothermal antibacterial agent. In addition, the photothermal conversion efficiency of BB-COF@Mn was also investigated. Figure 5 (b) is the photothermal effect of the aqueous dispersion of BB-COF@Mn (200 μg / mL) under 638 nm laser irradiation (1.5 W / cm 2 ²). When BB-COF@Mn (200 μg / mL) is irradiated at 638 nm (1.5 W / cm 2 ²), the temperature increases to 62.8 °C. After stopping the laser irradiation, the temperature decreases to room temperature. Therefore, the calculated photothermal conversion efficiency is 59.8% (the specific calculation formula refers to the photothermal conversion efficiency formula disclosed in the patent with the application number CN116333336A, a ferrocene-based metal-organic framework material and its preparation method and application).

[0039] (10) Detection of the photodynamic performance of BB-COF@Mn. Figure 6 The electron paramagnetic resonance spectrum shows that BB-COF@Mn can exert the ability to catalyze the generation of singlet oxygen. Figure 7 (a)~ Figure 7(b) shows the ability of BB-COF@Mn to generate singlet oxygen. Using DPBF as a probe and an 808 nm laser as the light source, the photodynamic properties of BB-COF@Mn were detected by ultraviolet-visible spectroscopy. The ability of BB-COF@Mn to generate singlet oxygen was evaluated by controlling the laser irradiation time and monitoring the absorption intensity of DPBF (1 mg / mL, 30 μL taken, DMSO as the solvent) at a wavelength of 418 nm in the mixture (DPBF + BB-COF@Mn + light irradiation). The results showed that, compared with the blank control (DPBF + light irradiation), BB-COF@Mn + DPBF + light irradiation (200 μg / ml, 1.5 W / cm 2 ) could generate a large amount of singlet oxygen in the first minute, the peak value of DPBF decreased significantly and rapidly, and the subsequent peak value decreased more slowly. DPBF was consumed by 99% under 15 minutes of light irradiation, which means that BB-COF@Mn generated a large amount of singlet oxygen under light irradiation.

[0040] (11) Detection of the light-controlled CO release ability and Fenton reaction of BB-COF@Mn. To study the CO release characteristics of BB-COF@Mn, a myoglobin (Mb) experiment was conducted.

[0041] Mb in horse skeletal muscle was first reduced to deoxymyoglobin (Deoxy-Mb) by sodium dithionite, and then BB-COF@Mn was added. Carbon monoxy myoglobin (MbCO) was generated by the reaction of Deoxy-Mb with CO. The amount of CO released was measured based on the ultraviolet-visible (UV-vis) absorbance difference between Deoxy-Mb (557 nm) and MbCO (540 and 577 nm).

[0042] From Figure 8 (a) and Figure 8 (b), it can be clearly observed that in the absence of BB-COF@Mn and light irradiation, the absorbance of Deoxy-Mb hardly changed. This indicates that under these conditions, no significant reaction occurred. However, when BB-COF@Mn was added and under laser irradiation, both the position and intensity of the absorption peak changed. This result fully demonstrates that BB-COF@Mn can effectively control CO release under laser irradiation.

[0043] In addition, the presence of Mn(CO)5Br endows BB-COF@Mn with peroxidase-like activity. Therefore, a dual-substrate system, namely H2O2 and 3,3',5,5'-tetramethylbenzidine (TMB), was used, where TMB serves as an indicator for the decomposition of H2O2 to generate •OH catalyzed by BB-COF@Mn. The experiment was divided into four groups: TMB, TMB + H2O2, TMB + H2O2 + BB-COF, and TMB + H2O2 + BB-COF@Mn. As can be seen from Figure 8 Figure (c), neither the TMB group nor the H2O2 + TMB group showed visible blue changes or detectable ultraviolet-visible absorption at a wavelength of 650 nm. In contrast, the BB-COF@Mn + H2O2 + TMB group exhibited obvious ultraviolet-visible absorption at 650 nm. By comparison, even in the presence of H2O2 and TMB, the BB-COF solution (i.e., the TMB + H2O2 + BB-COF group) did not show a blue change or detectable ultraviolet-visible absorption at a wavelength of 650 nm. This result indicates that the peroxidase-like catalytic activity of BB-COF@Mn is attributed to the presence of Mn(CO)5Br. As shown in Figure 8 Figure (d), under the experimental conditions of 1.5 mmol / L TMB, 20 mmol / L H2O2, triggered in an aqueous environment with pH = 4.5, as the concentration of BB-COF@Mn increased (50, 100, 125, 150, and 200 μg / mL), the generation of •OH in the system was significantly enhanced, and its ultraviolet absorption at 650 nm also increased. The results show that BB-COF@Mn has the ability to generate hydroxyl radicals.

[0044] Test Example 1: In vitro Bacterial Growth Inhibition Test 5 mL of LB liquid medium was added to a shaking flask. A single colony was picked from the uniformly spread LB solid medium containing Staphylococcus aureus or Escherichia coli using an inoculation loop and placed in the above 5 mL of LB liquid medium. The shaking flask was placed in a shaker and cultured at 37 °C for 8 - 12 hours until the OD value of the final bacterial solution at 600 nm was 0.1 (equivalent to a bacterial concentration of approximately 1×10 8 CFU / mL), and Staphylococcus aureus bacterial solution and Escherichia coli bacterial solution were obtained respectively.

[0045] (1) To verify the effect of BB-COF@Mn on bacterial activity, different concentrations of BB-COF@Mn dispersion (0, 50, 100, and 200 μg / mL) were prepared with PBS at pH 7 and BB-COF@Mn. 20 μL of H2O2 (20 mmol) was added, and they were respectively mixed with 100 μL of Staphylococcus aureus bacterial solution (1×10 8 CFU / mL) or Escherichia coli bacterial solution (1×10 8Mix with (××× CPU / mL), then make up to 1 mL with PBS at pH 7. After treatment with 638 nm laser irradiation for 15 min, incubate in a shaker at 37 °C for 8 h, and different numbers of colony counts were shown in the bacterial culture dishes. Figure 9 (a) are the culture diagrams of Staphylococcus aureus and Escherichia coli after treatment with different concentrations of BB-COF@Mn; Figure 9 (b) is the determination of the bacterial survival rate of Staphylococcus aureus and Escherichia coli by the plate counting method; it was found that the colony numbers of Staphylococcus aureus and Escherichia coli gradually decreased with the increase in the concentration of BB-COF@Mn. When the concentration of BB-COF@Mn reached 200 μg / mL, after irradiation for 15 min, the survival rates of Staphylococcus aureus and Escherichia coli were only 0.41% and 0.84%, respectively.

[0046] (2) To compare the antibacterial activities of the combined antibacterial modes of thermotherapy, photodynamic therapy, Fenton reaction and CO release, Staphylococcus aureus and Escherichia coli were treated with different groups, divided into 8 groups: PBS group (Group I), H2O2 (Group II), PBS + laser group (Group III), BB-COF group (Group IV), BB-COF + laser group (Group V), BB-COF@Mn group (Group VI), BB-COF@Mn + laser group (Group VII), BB-COF@Mn + H2O2 + laser group (Group VIII).

[0047] The specific treatment procedures for Group I and Group III are as follows: Take 80 μL of PBS at pH 7, mix it with 100 μL of Staphylococcus aureus bacterial solution (1×10 8 CPU / mL) or Escherichia coli bacterial solution (1×10 8 CPU / mL), then make up to 1 mL with PBS at pH 7 to obtain Group I; after further treatment with 638 nm laser irradiation for 15 min, Group V is obtained.

[0048] The specific treatment procedure for Group II is as follows: Take 80 μL of PBS at pH 7, mix it with 100 μL of Staphylococcus aureus bacterial solution (1×10 8 CPU / mL) or Escherichia coli bacterial solution (1×10 8 CPU / mL), add 20 μL of H2O2 (20 mmol), then make up to 1 mL with PBS at pH 7 to obtain Group II.

[0049] The specific treatment procedures for Group IV and V are as follows: Mix the BB-COF prepared in step (4) of Example 1 with PBS at pH 7 to obtain a BB-COF solution; Take 200 μL of the BB-COF solution (1 mg / mL) and 100 μL of Staphylococcus aureus bacterial solution (1×10 8CPU / mL) or Escherichia coli suspension (1×10 8 CPU / mL) were mixed, and then supplemented to 1 mL with PBS at pH 7 to obtain Group IV; after 15 min of laser irradiation at 638 nm, Group V was obtained.

[0050] The specific treatment processes of Groups VI, VII, and VIII were as follows: BB-COF@Mn prepared in Example 1 was mixed with PBS at pH 7 to obtain a BB-COF@Mn solution; 200 μL of the BB-COF@Mn solution (1 mg / mL) was taken and mixed with 100 μL of Staphylococcus aureus suspension (1×10 8 CPU / mL) or Escherichia coli suspension (1×10 8 CPU / mL), and then supplemented to 1 mL with PBS at pH 7 to obtain Group VI; after 15 min of laser irradiation at 638 nm, Group VII was obtained; then 20 μL of H2O2 (20 mmol) was added to obtain Group VIII.

[0051] The above 8 groups were cultured in a shaker at 37 °C for 8 h, and different numbers of colony counts were shown in the bacterial culture dishes. Then, the bacterial numbers of each group were estimated by the plate counting method. As Figure 10 shown, taking the PBS group (Group I) as the control group, it was found that a considerable number of colonies were observed in Groups II, III, IV, and VI. That is, there was no significant difference in the bacterial colony counts of the PBS treatment groups with or without laser irradiation, H2O2, BB-COF, and BB-COF@Mn groups. The BB-COF + laser group (Group V) showed a certain bactericidal effect, with the number of Staphylococcus aureus reduced to 54.6% and Escherichia coli reduced to 65.8%. This means that BB-COF caused the death of a certain number of bacteria through photothermal and photodynamic effects. The BB-COF@Mn + laser group (Group VII) also showed a similar bactericidal effect, with the number of Staphylococcus aureus reduced to 32.1% and Escherichia coli reduced to 39.5%. After treatment with the BB-COF@Mn + H2O2 + laser group (Group VIII), the numbers of Staphylococcus aureus and Escherichia coli were reduced to 0.41% and 0.83%, respectively. This indicates that the photothermal and photodynamic effects and the CO-releasing performance of BB-COF@Mn played a significant bactericidal role. This presented the significant broad-spectrum antibacterial performance of BB-COF@Mn by the combined action of four strategies.

[0052] Test Example 2: Observation of the morphology of bacteria by transmission electron microscopy To further understand the above antibacterial effect, the morphological structure changes of Escherichia coli and Staphylococcus aureus were studied by TEM ( Figure 11), grouped in the same way as in (2) of Test Example 1, into 8 groups: PBS group (Group I), H2O2 (Group II), PBS + laser group (Group III), BB-COF group (Group IV), BB-COF + laser group (Group V), BB-COF@Mn group (Group VI), BB-COF@Mn + laser group (Group VII), BB-COF@Mn + H2O2 + laser group (Group VIII). In the PBS group (I), H2O2 group (II) and PBS + laser group (III), the bacterial cell walls were intact and smooth, and the flagellar structures of Escherichia coli were clearly visible, indicating that PBS, light irradiation and H2O2 treatment had no antibacterial effect on Staphylococcus aureus and Escherichia coli; the BB-COF group (IV) only caused local membrane wrinkling, while the BB-COF + laser group (V) led to an increase in membrane permeability; BB-COF@Mn (VI) also only caused local membrane wrinkling, indicating that in the absence of laser irradiation and without CO release, there was only a limited antibacterial effect; while in the BB-COF@Mn + laser group (VII), under the synergistic action of the photothermal effect and CO release, the bacterial membrane structure and cell matrix were damaged; in the BB-COF@Mn + H2O2 + laser group (VIII), the hydroxyl radicals (•OH) generated by the Fenton reaction and CO acted together, resulting in the destruction of the bacterial membrane structure and the denaturation and leakage of the cell matrix. Therefore, it can be concluded that based on the photothermal, photodynamic and Fenton reactions induced by 638 nm laser and CO release, BB-COF@Mn can achieve rapid and efficient killing of Staphylococcus aureus and Escherichia coli through the combined application of four strategies.

[0053] Test Example 3: Hemolysis test Fresh blood was taken from BALB / c female mice (purchased from Beijing Vital River Laboratory Animal Technology Co., Ltd.), and the red blood cells were collected by centrifugation at 1500 rpm for 20 min and washed 3 times with PBS. The red blood cells (4% w / w) were mixed with PBS solutions of different concentrations of BB-COF@Mn (50, 100, 150, 200 and 250 μg / mL) at a ratio of 1:9 (v / v) and incubated in a shaker at 37 °C for 3 h, and then centrifuged at 12000 rpm for 20 min. The hemolytic effect of BB-COF@Mn was detected by measuring the absorbance at 540 nm of the supernatant after centrifugation of the erythrocyte solutions incubated with BB-COF@Mn solutions of different concentrations by ultraviolet-visible spectroscopy. Distilled water was used as the positive control (+), and PBS was used as the negative control (-). Figure 12 (a) shows the hemolysis rates of different concentrations of BB-COF@Mn on erythrocytes. It was found that as the concentration of BB-COF@Mn increased from 50 μg / mL to 250 μg / mL, the hemolysis rate remained below 1.5%, indicating that the material had good biocompatibility.

[0054] Test Example 4: Cytotoxicity test Cytotoxicity is also an important indicator for evaluating the biocompatibility of materials. Human embryonic kidney cells (HEK293 cells) and mouse fibroblasts (L929 cells) were selected for testing.

[0055] In a 96-well plate, HEK293 cells or L929 cells were inoculated at a density of 8×10 3 cells per well, with 100 µL of cell suspension per well. 100 µL of PBS was added to the surrounding wells for liquid sealing to prevent excessive evaporation. After 24 h of incubation, PBS (control group) and PBS solutions of different concentrations of BB-COF@Mn (50, 100, 150, and 200 µg / mL) were added for treatment. After 24 h of treatment, the supernatant was discarded, and then a medium containing 10 µL of MTT (5 mg / mL) and the same volume of PBS (pH = 7.4) solution was added to each well. After 4 h, the supernatant was aspirated, and 100 µL of DMSO was added to each well to dissolve the MTT-formazan crystals. After 5 min, the absorbance was measured at a wavelength of 490 nm in an enzyme-linked immunosorbent assay (ELISA) reader. Figure 12 Figure (b) shows the changes in cell viability after incubation of HEK293 cells or L929 cells with different concentrations of BB-COF@Mn. It can be seen that as the concentration of BB-COF@Mn increases, the survival rates of HEK293 cells and L929 cells slowly decrease after 24 h. When the concentration is 200 µg / mL, the survival rates of HEK293 cells and L929 cells still remain above 85%. This further demonstrates that BB-COF@Mn has good biocompatibility.

[0056] The above are only the preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. Preparation method of an organic polymer composite based on BODIPY photocontrolled CO release, characterized in that, It includes the following steps: (1) BODIPY undergoes an iodination reaction with an iodine-containing compound to obtain iodinated BODIPY; (2) The iodinated BODIPY, 3,5-diformylphenylboronic acid and potassium carbonate are dissolved in an organic solvent, a catalyst is added under a protective atmosphere and the reaction is carried out to obtain tetra-aldehyde BDP; (3) The tetra-aldehyde BDP and polyaminobipyridine are dissolved in an organic solvent, ultrasonically dispersed to form a suspension, and after cyclic deoxidation, the reaction is carried out by heating in a sealed environment to obtain a powdery black solid BB-COF; (4) Under a protective atmosphere, BB-COF and manganese pentacarbonyl bromide are suspended in anhydrous diethyl ether, and the reaction is stirred at room temperature to obtain an organic polymer composite material for BODIPY photo-controlled CO release.

2. The preparation method according to claim 1, characterized in that, In step (1), the iodine-containing compound is N-iodosuccinimide; the molar ratio of BODIPY to N-iodosuccinimide is 1:2; the iodination reaction is that BODIPY and N-iodosuccinimide are dissolved in anhydrous dichloromethane and stirred at room temperature for reaction.

3. The preparation method according to claim 1, characterized in that, In step (2), the molar ratio of iodinated BODIPY to 3,5-diformylphenylboronic acid is 1:2; the organic solvent is 1,4-dioxane; the catalyst is tetrakis(triphenylphosphine)palladium.

4. The preparation method according to claim 1, characterized in that, In step (2), the temperature of the reaction is 120 °C and the reaction time is 12 h.

5. The preparation method according to claim 1, characterized in that, In step (3), the polyaminobipyridine is 2,2'-bipyridine-5,5'-diamine; the organic solvent is a mixture of toluene and acetic acid solution in a volume ratio of 20:1; the concentration of the acetic acid solution is 3 M; the temperature of the heating reaction is 120 °C and the reaction time is 72 h.

6. The preparation method according to claim 5, characterized in that, The molar ratio of the tetra-aldehyde BDP to 2,2'-bipyridine-5,5'-diamine is 1:

2.

7. The preparation method according to claim 1, characterized in that, In step (4), the molar ratio of BB-COF to manganese pentacarbonyl bromide is 1:4; the reaction time of the room temperature stirring reaction is 4 h.

8. The organic polymer composite based on BODIPY photocontrolled CO release obtained by the preparation method according to any one of claims 1 to 7, characterized in that, The organic polymer composite material for BODIPY photo-controlled CO release is polymerized with poly-aldehyde BDP and polyaminobipyridine as monomers, and manganese pentacarbonyl bromide is loaded by using the multidentate ligand of bipyridine; the organic polymer composite material for BODIPY photo-controlled CO release has an eggshell-like spherical structure and releases CO under laser irradiation.

9. The organic polymer composite material based on BODIPY light-controlled CO release according to claim 8, wherein, The poly-aldehyde BDP is tetra-aldehyde BDP; the polyaminobipyridine is 2,2'-bipyridine-5,5'-diamine.

10. Use of the organic polymer composite material for BODIPY photo-controlled CO release according to claim 8 or 9 in the preparation of antibacterial drugs.

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