Perylene bisimide photo-thermal diagnosis and treatment agent, preparation method thereof and product containing perylene bisimide photo-thermal diagnosis and treatment agent

Abstract

The invention discloses a perylene bisimide photo-thermal diagnosis and treatment agent, a preparation method thereof and a product containing the perylene bisimide photo-thermal diagnosis and treatment agent, and belongs to the technical field of organic materials. The chemical structural formula of the perylene bisimide photo-thermal diagnosis and treatment agent is # imgabs0, bay site modification is carried out on micromolecule perylene bisimide to obtain the perylene bisimide photo-thermal diagnosis and treatment agent, then the perylene bisimide photo-thermal diagnosis and treatment agent and hydrophobic molecules are self-assembled to obtain a polymer, and the polymer is further combined with aldehyde poloxamer (F127-CHO) and amino hydroxypropyl chitosan (HPCS) to obtain the perylene bisimide photo-thermal diagnosis and treatment agent. The injectable temperature-sensitive hydrogel is formed. The synthesis route is simple and efficient, the raw material perylene bisimide molecules used for synthesis are easy to metabolize and non-toxic, and the obtained hydrogel has good biocompatibility and can eliminate inflammation, promote angiogenesis and accelerate the wound healing process in cooperation with a PTT / NO treatment strategy so as to effectively resist bacterial biofilms.

Description

Technical Field

[0001] The present invention belongs to the technical field of organic materials, and in particular relates to a perylene imide photothermal diagnostic agent, a preparation method thereof, and a product containing the same. Background Art

[0002] Bacterial biofilm infection can cause serious damage to the wound surface and hinder the healing process of the wound surface, posing a great threat to public health. Biofilms in deep tissues are usually difficult for drugs to reach. To date, antibiotics are still the main treatment strategy in the clinical treatment of infected wounds, and hydrogels not only play a physical barrier role against external infections, but also regulate conditions that are conducive to wound healing. In recent years, injectable hydrogels have shown great promise in fighting biofilm infections because of their extraordinary drug loading properties and ability to conform to any irregular wound surface. Many innovative antibiotics containing hydrogels have been reported. However, due to the protective extracellular polymers, biofilms are usually difficult to penetrate and eradicate by conventional antibiotics, resulting in poor treatment effects and enhanced drug resistance. Therefore, removing biofilms and promoting wound healing remain clinical challenges. Summary of the invention

[0003] In view of the above technical problems, the present invention proposes a perylene imide photothermal diagnostic agent, a preparation method thereof, and a product containing the same. Among them, the hydrogel based on the perylene imide photothermal diagnostic agent prepared by the present invention is a thermosensitive, photothermal and gas therapy synergistic injectable antibacterial hydrogel, which effectively demonstrates the ability to eliminate inflammation, promote angiogenesis, and promote collagen deposition, thereby significantly stimulating the wound healing process. Its light-regulated NO transport characteristics, injectability and antibacterial properties provide an effective prospect for the treatment of biofilm-infected wounds.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] One of the technical solutions of the present invention:

[0006] A perylene diimide photothermal diagnostic agent (PDI-5) having the chemical structural formula:

[0007]

[0008] The second technical solution of the present invention:

[0009] A method for preparing a perylene imide photothermal diagnostic and therapeutic agent, comprising the following steps:

[0010] (1) Perylene tetracarboxylic dianhydride, I2, Br2 and concentrated sulfuric acid (mass concentration: 98%) were mixed and stirred at 95°C under N2 for 18 h, and then filtered, washed and dried in sequence to obtain red powder PDI-2; the synthesis route is as follows:

[0011]

[0012] (2) PDI-2, α-phenylethylamine and propionic acid were mixed, dissolved in 1-methyl-2-pyridone (NMP), stirred at 85°C under N2 for 6 h, and then separated, washed and dried in sequence to obtain red powder PDI-3; the synthesis route is as follows:

[0013]

[0014] (3) PDI-3 and N-Boc-1,6-diaminohexane were dissolved in NMP and stirred at 95°C under N2 for 12 h. The resulting mixture was poured into a mixed solution of methanol / dilute hydrochloric acid (90 / 10 mL). After filtration, washing and drying, a green solid PDI-4 was obtained. The synthetic route is shown below:

[0015]

[0016] (4) PDI-4 was dissolved in CH2Cl2 under a nitrogen atmosphere; BBr3 was added to the CH2Cl2 at 0°C, and the mixture was stirred at 0°C for 30 minutes and at room temperature for 4 hours; distillation, ultrasonication, filtration and drying were then performed in sequence to obtain a green solid (PDI-5 crude product); the PDI-5 crude product was dissolved in DMSO (dimethyl sulfoxide), and CH2Cl2 was added thereto to obtain PDI-5; the synthetic route is shown below:

[0017]

[0018] Beneficial effects: The present invention replaces two methylenediamines at the bay position of small molecule perylene imide and chemically removes the amide substitute at the imine position, so that the stacking ability of the molecule is further optimized.

[0019] Optionally, the preparation method further comprises step (5), specifically: dissolving PDI-5 in DMSO, adding the mixture dropwise into a PBS solution under ultrasonic conditions, washing the mixture three times with a PBS solution, and freeze-drying the mixture to obtain J-aggregated PDI-5.

[0020] Beneficial effects: When the prepared PDI-5 is dissolved in PBS, the J-aggregated PDI-5 can grow in one-dimensional direction, which further strengthens the J aggregation. In deionized water, PDI-5 exhibits H-aggregated nanoparticles.

[0021] Optionally, the molar ratio of perylenetetracarboxylic dianhydride to Br2 in step (1) is 1:4 to 1:8.

[0022] Optionally, the molar ratio of PDI-2 to α-phenylethylamine in step (2) is 1:2 to 1:5.

[0023] Optionally, the molar ratio of PDI-3 to N-Boc-1,6-diaminohexane in step (3) is 1:2 to 1:10.

[0024] Optionally, the molar ratio of PDI-4 to boron tribromide in step (4) is 1:50 to 1:100.

[0025] The third technical solution of the present invention:

[0026] Application of the above-mentioned perylene imide photothermal diagnostic and therapeutic agent in the preparation of antibacterial medical materials.

[0027] The fourth technical solution of the present invention:

[0028] An antibacterial hydrogel, the raw materials of which include the above-mentioned perylene imide photothermal diagnostic and therapeutic agent.

[0029] Optionally, the hydrogel comprises the following raw materials:

[0030] SR formed by self-assembly of NO donor BNN6 and perylene diimide photothermal therapeutic agent (PDI-5), F127 containing formyl group (F127-CHO) and hydroxypropyl chitosan (HPCS) with amino group;

[0031] Wherein, the structural formula of BNN6 is:

[0032]

[0033] The structural formula of the F127 (F127-CHO) containing formyl group is:

[0034]

[0035] Beneficial effect: The present invention uses PD-5 as an element to regulate NO release, and BNN6 as a NO donor. NO is released under photothermal regulation and further converted into ONOO with strong bactericidal properties. - At the same time, the thermal effect is used to increase the permeability of bacterial biofilms to exogenous substances, which is used to achieve the treatment of bacterial biofilms.

[0036] Further, the synthesis process of BNN6:

[0037] The BNN6 is obtained by reacting N,N-sec-butylamino-p-phenylenediamine and NaNO2 under acidic conditions, and then centrifuging, washing and drying in sequence.

[0038] Furthermore, the molar ratio of the N,N-di-sec-butyl-p-phenylenediamine to sodium nitrite is 1:1 to 1:4.

[0039] Optionally, the synthesis process of the formyl-containing F127 (F127-CHO) is:

[0040] Polyether F127 (whose structural formula is ) and DCC (N,N'-dicyclohexylcarbodiimide) were dissolved in DMF and freeze-thawed, and then p-formylbenzaldehyde was added thereto for reaction, followed by filtering, centrifugation and drying in sequence to obtain white powder F127-CHO.

[0041] Furthermore, the molar ratio of the polyether F127 to p-formylbenzoic acid is 1:1 to 1:8.

[0042] Furthermore, the hydrogel comprises the following raw materials in terms of mass ratio:

[0043] The mass ratio of F127-CHO, HPCS and SR is 50:20:1.

[0044] Optionally, the preparation process of the SR is: mixing BNN6 and perylene imide photothermal therapeutic agent in a mass ratio of 2:5, and then self-assembling at 25° C. for 6 hours to form SR.

[0045] The fifth technical solution of the present invention:

[0046] A method for preparing an antibacterial hydrogel comprises the following steps:

[0047] SR is added to a PBS solution of HPCS to obtain a mixed solution, and then the mixed solution is mixed with a PBS solution of F127-CHO, and vortex and ultrasonic treatment are performed in sequence to obtain the antibacterial hydrogel.

[0048] Optionally, the concentration of the HPCS PBS solution is 4% (w / v);

[0049] The concentration of the F127-CHO in PBS solution is 10% (w / v).

[0050] Optionally, the vortex time is 10s;

[0051] The ultrasonic time is 2 minutes.

[0052] Compared with the prior art, the present invention has the following advantages and technical effects:

[0053] 1. The present invention is to modify the bay site of small molecule perylene imide, and then self-assemble the obtained product with a hydrophobic molecule (NO donor BNN6) to obtain the polymer, which is further combined with aldehyde poloxamer (F127-CHO) and amino-containing hydroxypropyl chitosan (HPCS) to form an injectable thermosensitive hydrogel.

[0054] The specific mechanism of the hydrogel of the present invention is as follows: the PDI-5 obtained by modifying perylene imide in the present invention has significant J aggregation characteristics, and under the joint action of F127-CHO, the J aggregation of PDI-5 is further enhanced, so that it has good hydrophobic carrier characteristics and good drug carrying capacity. By making full use of the hydrophobic skeleton of PDI-5, the drug (NO donor BNN6) encapsulation rate can reach 83.5%; and PDI-5 can absorb near-infrared zone II light, so the gel can be used for biofilm treatment deep in the tissue, and gas synergistic treatment provides further guarantee for the killing of deep tissue biofilm; further, the PDI-5 prepared by the present invention itself has good photothermal conversion efficiency, and at the same time has good NO regulation and release ability, and the construction of its J-polymer can significantly improve the photothermal conversion efficiency of the hydrogel, reaching 72%, further enhancing the regulation and release of NO.

[0055] In addition, the present invention utilizes F127-CHO and HPCS to combine through Schiff base reaction, which has high mechanical strength and photothermal stability. At the same time, the Schiff base bond gives the hydrogel an outstanding self-repairing ability during the formation and breaking process.

[0056] 2. The synthesis route of the present invention is simple and efficient, the raw material perylene imide molecules used in the synthesis are easy to metabolize and non-toxic, and the obtained hydrogel has good biocompatibility, and cooperates with the PTT (photothermal therapy) / NO treatment strategy to eliminate inflammation, promote angiogenesis, and accelerate the wound healing process to effectively fight bacterial biofilm. That is, the hydrogel based on super J-polymer prepared by the present invention can provide a solution for precise antibacterial applications.

[0057] In summary, the present invention effectively enhances the penetration ability of reactive oxygen molecules and the ability of gel to kill bacterial biofilms through the synergy of photothermal and gas therapy. The damage rate to common bacterial biofilms exceeds 88%, and the killing rate to common free bacteria exceeds 99.5%. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0059] Figure 1 The synthetic route for synthesizing the perylene imide photothermal diagnostic and therapeutic agent in Example 1 is shown in FIG.

[0060] Figure 2 The PDI-3 prepared in Example 1 1 H NMR spectrum;

[0061] Figure 3 The PDI-4 prepared in Example 1 1 H NMR spectrum;

[0062] Figure 4 The PDI-5 prepared in step 14) of Example 1 1 H NMR spectrum;

[0063] Figure 5 The BNN6 prepared in Example 1 1 H NMR spectrum;

[0064] Figure 6 The F127-CHO prepared in Example 1 1 H NMR spectrum;

[0065] Figure 7 This is a SEM scanning photograph of the J-aggregated PDI-5 prepared in step 15) of Example 1;

[0066] Figure 8 The heating and cooling curves of PDI-5monomer, J fibers and J NPs (left) and the corresponding thermal infrared imaging photos (right);

[0067] Fig. 9 The graph showing the modulus change during the gelation process of the hydrogel prepared in Example 1 (left) and the self-healing performance characterization graph (right);

[0068] Fig.10 This is a SEM scanning photograph of the hydrogel prepared in Example 1;

[0069] Fig.11 This is a thermal infrared photograph of the photothermal effect of the hydrogel prepared in Example 1;

[0070] Fig.12 The photothermal conversion efficiency statistics of the hydrogel SRH and PDI-5monomer, J fibers and J NPs prepared in Example 1 are shown in FIG.

[0071] Fig.13 NO release diagram of the hydrogel SRH prepared in Example 1 under and without laser irradiation;

[0072] Fig.14 This is a diagram showing the antibacterial effect of the hydrogel SRH prepared in Example 1 with and without laser irradiation. DETAILED DESCRIPTION

[0073] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0074] It should be understood that the terms described in the present invention are only for describing special embodiments and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0075] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0076] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to those skilled in the art. The present invention description and examples are exemplary only.

[0077] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0078] The embodiment of the present invention discloses a perylene imide photothermal diagnostic and therapeutic agent, which has significant J aggregation characteristics and good photothermal effect after conventional perylene imide compounds are polymerized and modified. The structural formula is:

[0079]

[0080] Also disclosed is a method for synthesizing a perylene imide photothermal diagnostic and therapeutic agent, comprising the following steps:

[0081] (1) Perylene tetracarboxylic dianhydride, I2, Br2 and concentrated sulfuric acid were mixed and stirred at 95°C under N2 for 18 days, cooled and placed in water, and the red precipitate was separated by suction filtration and washed with deionized water. Thus, the residue PDI-2 was dried under vacuum to obtain red powder PDI-2;

[0082]

[0083] (2) PDI-2, α-phenylethylamine and propionic acid were mixed in 1-methyl-2-pyridone (NMP), stirred at 85°C under N2 for 6 h, cooled and poured into water, filtered to obtain a red precipitate, washed with deionized water, and then dried under vacuum to obtain a red powder. The crude product was purified by silica gel column chromatography to obtain PDI-3;

[0084]

[0085] (3) PDI-3 was mixed with N-Boc-1,6-diaminohexane in NMP, stirred at 95°C under N2 for 12 h, and the hot reaction mixture was poured into a mixed solution of methanol / dilute hydrochloric acid (90 / 10 mL). The precipitate was collected by filtration, washed with methanol three times, and dried under vacuum at room temperature overnight to obtain a green solid; the crude product was purified by silica gel column chromatography to obtain PDI-4;

[0086]

[0087] (4) PDI-4 was dissolved in CH2Cl2 under nitrogen atmosphere; BBr3 solution was added to the CH2Cl2 at 0°C within 10 minutes; the color of the reaction mixture immediately changed from green to red after the addition of BBr3; the solution was stirred at 0°C for 30 minutes and then stirred at room temperature for another 4 hours; the solvent and excess BBr3 were distilled out under vacuum, and the residue was cooled to 0°C; a mixture of methanol / PBS (methanol to PBS volume ratio of 1:4) was then added to the solid, and the suspension was treated in an ultrasonic bath at 50°C for 30 minutes; it was filtered and dried under vacuum to obtain a green solid; the green solid was dissolved in DMSO (dimethyl sulfoxide), and PDI-5 was obtained by adding CH2Cl2 to DMSO;

[0088] (5) PDI-5 was dissolved in DMSO, added dropwise into a PBS solution under ultrasonic conditions, washed three times with PBS solution, and freeze-dried to obtain J-aggregated PDI-5.

[0089] In some optional embodiments, the molar ratio of perylenetetracarboxylic dianhydride to liquid bromine used in step (1) is 1:4 to 1:8.

[0090] In some optional embodiments, the molar ratio of PDI-2 to α-phenylethylamine used in step (2) is 1:2 to 1:5.

[0091] In some optional embodiments, the molar ratio of PDI-3 to N-Boc-1,6-diaminohexane used in step (3) is 1:2 to 1:10.

[0092] In some optional embodiments, the molar ratio of PDI-4 to boron tribromide used in step (4) is 1:50 to 1:100.

[0093] In addition, an embodiment of the present invention also discloses a thermosensitive hydrogel based on perylene imide photothermal therapeutic agent, comprising: SR formed by self-assembly of NO donor BNN6 and PDI-5, F127 (F127-CHO) containing a formyl group, and hydroxypropyl chitosan (HPCS) containing an amino group.

[0094] In some optional embodiments, the synthesis process of BNN6 is:

[0095] N,N-sec-butylamino-p-phenylenediamine was diluted into an ethanol solution, and then added to a NaNO2 aqueous solution under stirring and nitrogen protection. After 30 minutes, a HCl aqueous solution was added dropwise using a constant pressure funnel. The reaction solution gradually changed from red to orange, and a beige precipitate was produced. After stirring for 4 hours, the solid product was collected by centrifugation, and the collected precipitate was washed several times with ethanol / water in sequence to remove the residual reactants, and then freeze-dried in the dark overnight to obtain BNN6, whose structural formula is:

[0096]

[0097] The molar ratio of N,N-di-sec-butyl-p-phenylenediamine to sodium nitrite is 1:1 to 1:4.

[0098] In some optional embodiments, the synthesis process of F127-CHO is:

[0099] After polyether F127 and DCC were dissolved in DMF, they were frozen and thawed three times with liquid nitrogen to remove oxygen. Under a nitrogen atmosphere, p-formylbenzaldehyde was added to the mixture and refluxed at 80°C overnight. After the reaction was cooled, the solution was filtered and evaporated to remove the solvent to obtain a yellow viscous substance, into which ether solution was dropped, and impurities in the solution were removed by centrifugation to obtain a white powder product, which was further purified by column chromatography to obtain a white powder F127-CHO with the structural formula:

[0100]

[0101] The molar ratio of the polyether F127 to the p-formylbenzoic acid is 1:1 to 1:8.

[0102] The PDI-5 prepared in the embodiment of the present invention has a good photothermal effect and can be used as a photothermal agent. Its strong π-π stacking effect can be used to load the NO donor BNN6. The amino group it carries can also be well combined with the hydrogel system to prepare a photothermal / NO synergistic therapeutic hydrogel dressing for the treatment of bacterially infected wounds.

[0103] The "room temperature" in the present invention refers to 20-30°C unless otherwise specified.

[0104] The raw materials used in the present invention are all purchased from the market. The structural formula of the amino-containing hydroxypropyl chitosan used in the following examples is:

[0105]

[0106] Where n≈8032, the molecular weight: 2×10 6 g mol -1 , degree of substitution: 0.85, degree of deacetylation: 90%; purchased from Nantong Lvshen Bioengineering Co., Ltd.

[0107] The technical solution of the present invention is further illustrated by the following embodiments.

[0108] Example 1

[0109] A thermosensitive hydrogel based on perylene imide photothermal diagnostic and therapeutic agent, comprising: SR formed by self-assembly of NO donor BNN6 and PDI-5, F127 (F127-CHO) containing formyl group and hydroxypropyl chitosan (HPCS) containing amino group;

[0110] The preparation method of the temperature-sensitive hydrogel comprises the following steps:

[0111] (1) Preparation of perylene imide photothermal diagnostic and therapeutic agents with significant J aggregation properties, the synthesis route of which is as follows Figure 1 As shown:

[0112] 11) Perylenetetracarboxylic dianhydride (2 g, 5.0 mmol), I2 (0.11 g, 0.4 mmol), Br2 (4.8 g, 30.0 mmol) and fuming sulfuric acid (100 mL) were mixed and stirred at 95 ° C and N2 for 18 h. After the reaction, the mixture was placed in cold water, the red precipitate was separated by suction filtration, and washed with deionized water. Dry under vacuum to obtain red powder PDI-2;

[0113] 12) PDI-2 (1.1 g, 2.0 mmol), α-phenylethylamine (0.48 g, 4.0 mmol), propionic acid (5 g, 8.33 mmol) were mixed in 1-methyl-2-pyridone (NMP) (100 mL), stirred at 85 ° C and N2 for 6 h, poured into water after cooling, filtered to separate the red precipitate, and washed with deionized water; then dried under vacuum to obtain a red powder; the crude product was purified by silica gel column chromatography (CH2Cl2 as eluent) to obtain PDI-3, PDI-3 1 H NMR spectrum is shown in Figure 2 ;

[0114] 13) PDI-3 (1 g, 1.32 mmol) and N-Boc-1,6-diaminohexane (1.43 g, 6.6 mmol) were mixed in NMP (100 mL) and stirred at 95 ° C. under N2 for 12 h; during this period, the color of the solution changed from red to green; the reaction mixture was poured into a solution of methanol / 2M HCl (90 / 10 mL); the precipitate was collected by filtration, washed with methanol 3 times, and dried under vacuum at room temperature overnight to obtain a green solid; the crude product was purified by silica gel column chromatography (methanol / CH2Cl2=1:250) to obtain 285 mg PDI-4 (yield 21%), PDI-4 1 HNMR spectrum see Figure 3 ;

[0115] 14) PDI-4 (50 mg, 0.05 mmol) was dissolved in 25 mL CH2Cl2 under nitrogen protection;

[0116] At 0°C, add 0.25 mL, 16.7 mmol, of BBr3 solution to the above 10 mL of CH2Cl2 and PDI-4 mixed solution, and drip the solution over 10 minutes;

[0117] After adding BBr3, the color of the reaction mixture immediately changed from green to red. Stir at 0°C for 30 minutes and then stir at room temperature for another 4 hours. Distill the solvent and excess BBr3 under vacuum and cool the residue to 0°C. Then add 50mL of a mixture of methanol / PBS (methanol to PBS volume ratio of 1:4) to the solid (residue) to obtain a suspension, and treat the suspension in an ultrasonic bath at 50°C for 30 minutes. Filter and dry under vacuum to obtain a green solid. The green solid was dissolved in DMSO (dimethyl sulfoxide), and PDI-5 (24 mg, 80%) was obtained by adding CH2Cl2 to DMSO. 1 H NMR spectrum is shown in Figure 4 ;

[0118] 15) 5 mg of PDI-5 was dissolved in 2 ml of DMSO, added dropwise into 10 ml of PBS solution under ultrasonic conditions, washed three times with PBS solution, and freeze-dried to obtain J-aggregated PDI-5;

[0119] Figure 7 This is a SEM scanning photograph of the J-aggregated PDI-5 prepared in Example 1; as can be seen from the figure, the molecules in the PDI-5 obtained by modifying the perylene imide in the present invention are arranged in a head-to-tail manner to form a one-dimensional chain (fibrous shape), so that it has significant J aggregation characteristics and good hydrophobic carrier characteristics, that is, good drug carrying capacity.

[0120] (2) Synthesis of NO donor BNN6:

[0121] 2.34 mL (10 mmol) of N,N-sec-butylamino-p-phenylenediamine was added to 18 mL of ethanol, and then 20 mL of 6 M degassed NaNO2 aqueous solution was added under stirring and nitrogen protection; after 30 minutes, 20 mL of 6 M HCl aqueous solution was added dropwise using a constant pressure funnel; the reaction solution gradually changed from red to orange, and a beige precipitate was produced; after stirring for 4 hours, the solid product was collected by centrifugation, and the collected precipitate was washed with water and 50% (v / v) ethanol / water for several times in sequence to remove the residual reactants, and then freeze-dried in the dark overnight to obtain BNN6. 1 H NMR spectrum is shown in Figure 5 ;

[0122] (3) Synthesis of F127-CHO:

[0123] Dissolve polyether F127 and DCC (N, N'-dicyclohexylcarbodiimide) in DMF, then freeze-thaw three times with liquid nitrogen to remove oxygen. Add the mixture to p-formylbenzaldehyde under nitrogen atmosphere and reflux overnight at 80°C. After the reaction is cooled, filter the solution and evaporate to remove the solvent to obtain a yellow viscous substance. Add ether solution and centrifuge to remove impurities in the solution to obtain a white powder product. Further purify by column chromatography to obtain a white powder F127-CHO. 1 H NMR spectrum is shown in Figure 6 .

[0124] (4) Preparation of thermosensitive hydrogel SRH:

[0125] 41) Dissolve 1 g of F127-CHO in 10 mL of PBS to prepare a 10% (w / v) solution 1;

[0126] 42) 0.4 g of HPCS was dissolved in 10 mL of PBS to prepare a 4% (w / v) solution; then, 4 mg of SR (a "sandwich roll" prepared by π-π stacking and hydrogen bonding of PDI-5) was added to 2 mL of the above HPCS solution to obtain solution 2;

[0127] Among them, the preparation process of SR is: BNN6 prepared in step (2) and J-aggregated PDI-5 (perylene imide photothermal therapeutic agent) prepared in step 15) are self-assembled at a mass ratio of 2:5 at 25°C for 6 hours to form SR.

[0128] 43) The two solutions (solution 1 and solution 2) were mixed in equal volumes, vortexed for 10 seconds, and sonicated for 2 minutes to obtain an injectable and self-healing hydrogel named SRH. The prepared hydrogel included 5wt% F127-cho, 2wt% HPCS and 0.1wt% SR.

[0129] Fig.10 This is a SEM scanning photo of the hydrogel prepared in Example 1; it can be seen from the figure that the hydrogel prepared in this example has an interpenetrating porous structure, and this unique structure can not only continuously absorb wound secretions, but also maintain a moist environment, further promoting wound healing. That is, this structure makes the gel have a good hemostatic effect.

[0130] Comparative Example 1 (F127H single hydrogel group)

[0131] The difference from Example 1 is that the raw materials in the hydrogel only contain HPCS and F127-CHO, and do not contain nitric oxide donor BNN6 and J-aggregated PDI-5 (perylene diimide photothermal therapeutic agent). The raw material dosage ratio and preparation process are the same as in Example 1.

[0132] Comparative Example 2 (JFH photothermal group)

[0133] The difference from Example 1 is that the raw materials in the hydrogel only contain J-aggregated PDI-5 (perylene imide photothermal diagnostic agent), HPCS and F127-CHO, and do not contain nitric oxide donor BNN6. The raw material dosage ratio and preparation process are the same as in Example 1.

[0134] Effect verification:

[0135] 1. Heating and cooling curves of different aggregation samples:

[0136] Take 0.3 ml of sample and place it in a sample tube. Then irradiate it with 808 nm laser continuously. The laser power is 1 W cm -2 , after continuous irradiation for 5 min, the laser was turned off, cooled for 5 min, and the sample temperature was recorded with a thermal infrared camera.

[0137] The samples are: PDI-5 in three different aggregation states (prepared in step 14 of Example 1):

[0138] ① PDI-5monomer: Dissolve the PDI-5 (2 mg) prepared above in 5 ml DMSO to obtain a PDI-5monomer solution;

[0139] ② J fibers: Dissolve the PDI-5 (5 mg) prepared above in 2 ml DMSO, add dropwise into 10 ml PBS solution under ultrasonic environment, and wash with PBS solution for 3 times to obtain J fiber solution;

[0140] ③J NPs: 2 mg of PDI-5 and 10 mg of polyether F127 prepared above were dissolved in 1 ml of DMSO, added dropwise into 10 ml of PBS solution under ultrasonic environment, and washed with PBS solution for 3 times to obtain JNPs solution.

[0141] Figure 8 The heating and cooling curves of the three samples (left) and the corresponding thermal infrared imaging photos (right); it can be seen that after the formation of fibrous J aggregates (J fibers), the photothermal conversion efficiency is significantly improved compared with the PDI-5 monomer (PDI-5monomer) and ordinary J aggregates (JNPs).

[0142] 2. Gel Formation Process Modulus Test

[0143] The gelation process was confirmed by time sweep test. After ultrasonication for 2 min in step 43), the mixed solution of F127-CHO and SR-based HPCS was immediately tested by rheometer.

[0144] The self-healing ability of SRH was tested using a strain of 700%. The rheometer was set to 700% for 2 min, and then set to 1% for 2 min; this cycle was repeated for 3 cycles to observe the change in gel modulus.

[0145] Fig. 9 The modulus change diagram (left) and self-healing performance characterization diagram (right) of the hydrogel prepared in Example 1 during the gelation process; it can be seen that G' represents the storage modulus and G" represents the loss modulus. As can be seen from the left figure, 60s after the two solutions are mixed, the storage modulus is greater than the loss modulus, indicating that the gel is formed 60s after mixing; as can be seen from the right figure, when the large shear destroys the hydrogel structure, it is replaced by small shear and the gel structure is restored, proving the good repairability.

[0146] 3. Photothermal test of gel formation

[0147] 0.3 ml of gel (the temperature-sensitive hydrogel SRH prepared in Example 1) was placed in a sample tube and continuously irradiated with 808 nm laser at a laser power of 1 W cm -2 , after continuous irradiation for 5 min, the laser was turned off and the sample temperature was recorded with a thermal infrared camera.

[0148] Fig.11This is a thermal infrared photograph of the photothermal effect of the hydrogel prepared in Example 1; it can be seen from the figure that with the irradiation of the near-infrared laser, the gel heats up significantly.

[0149] 4. Calculation of Photothermal Conversion Efficiency

[0150] The photothermal conversion efficiency of the samples (J fibers, PDI-5 monomer, J NPs and SRH) was calculated according to the following formula:

[0151]

[0152] In the above formula, η: photothermal conversion efficiency;

[0153] h: thermal conductivity, unit is W / (m 2 K);

[0154] A: sample surface area, in m 2 ;

[0155] ΔT max : Maximum temperature rise, that is, the difference between the highest temperature of the sample under light and the ambient temperature, in K or °C;

[0156] Q dis : Heat dissipation power, in W, represents the energy loss caused by heat dissipation;

[0157] I: incident light intensity, in W / m 2 , represents the optical power per unit area of ​​the sample;

[0158] A laser : Light absorption rate, which indicates the degree of absorption of a sample to a laser of a specific wavelength.

[0159] Fig.12 The photothermal conversion efficiency statistics of the hydrogel SRH and J fibers, PDI-5monomer and J NPs prepared in Example 1 are shown in the figure. It can be seen from the figure that the PDI-5 prepared by the present invention has good photothermal conversion efficiency itself and good NO regulation release ability. The construction of its J-polymer can significantly improve the photothermal conversion efficiency of the hydrogel to 72%, further enhancing the regulation release of NO.

[0160] 5. NO Release Test of Thermosensitive Hydrogel SRH

[0161] The NO release behavior of gel SRH was determined by a commercial Griess assay kit. Briefly, a series of 500 μL gel SRH samples were incubated with 500 μL PBS in a test tube and then illuminated with an 808 nm near-infrared laser (1 W cm -2) or not irradiated. Take 50 μL of the supernatant at different time intervals, mix with 100 μL of Griess reagent, incubate in the dark for 20 min, measure the absorbance at 540 nm with an enzyme reader, and calculate the NO concentration according to the standard curve.

[0162] Fig.13 This is the NO release diagram of the hydrogel SRH prepared in Example 1. As can be seen from the figure, the hydrogel prepared in the present invention is exposed to 808nm near-infrared laser (1W cm -2 ) can reach a release concentration of nitric oxide within 50 minutes; while without near-infrared laser irradiation, its release concentration is only about 5 μM. This proves that the hydrogel has a good photothermal effect and can effectively regulate the release of NO.

[0163] VI. In vitro antibacterial effect test of thermosensitive hydrogel SRH

[0164] The Staphylococcus aureus suspension was diluted to a specific concentration (1×10 8 CFU / mL). 500 μL of the above suspension was incubated with 500 μL of hydrogel and irradiated with or without laser for 5 min (0.5 W cm -2 ). Subsequently, 1 mL of sterilized PBS was added to each well to resuspend the treated bacteria, and the bacterial suspension was serially diluted 1000 times with PBS. When agar coating, 100 μL of the diluted suspension was evenly coated on the LB agar plate with a sterile coating machine, incubated at 37°C overnight (12 h), and the colony forming units (CFU) were counted.

[0165] Fig.14 The figure is an antibacterial effect diagram of the hydrogel SRH prepared in Example 1; wherein the Control group is a blank group, the F127H group (Comparative Example 1) is a single hydrogel group; the JFH (Comparative Example 2) is a photothermal group; and the SRH (Example 1) is a photothermal synergistic NO group; as can be seen from the figure, the hydrogel prepared by the present invention, through the synergy of photothermal and gas therapy, effectively enhances the penetration ability of reactive oxygen molecules and the ability of the gel to kill bacterial biofilms. The damage rate to common bacterial biofilms is more than 88%, and the killing rate to common free bacteria is more than 99.5%.

[0166] The above are only preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A perylene imide photothermal diagnostic and therapeutic agent, characterized in that: Its chemical structure is:

2. A method for preparing a perylene imide photothermal diagnostic and therapeutic agent, characterized in that: The specific steps include: (1) mixing perylene tetracarboxylic dianhydride, I2, Br2 and fuming sulfuric acid at 95°C under N2 conditions, stirring for reaction, and then filtering, washing and drying in sequence to obtain red powder PDI-2; (2) mixing the PDI-2, α-phenylethylamine and propionic acid, dissolving them in 1-methyl-2-pyridone, stirring and reacting at 85° C. under N2 conditions, and then separating, washing and drying in sequence to obtain red powder PDI-3; (3) dissolving the PDI-3 and N-Boc-1,6-diaminohexane in 1-methyl-2-pyridone, stirring and reacting at 95° C. under N2 conditions, pouring the resulting mixture into a mixed solution of methanol and dilute hydrochloric acid; filtering, washing and drying to obtain a green solid PDI-4; (4) Dissolving the PDI-4 in CH2Cl2 under a nitrogen atmosphere; adding BBr3 to the CH2Cl2 solution at 0°C, stirring at 0°C for 30 minutes and at room temperature for 4 hours; then distilling, ultrasonicating, filtering and drying to obtain a green solid; dissolving the green solid in dimethyl sulfoxide, and adding CH2Cl2 thereto to obtain PDI-5, i.e., the perylene imide photothermal diagnostic agent according to claim 1.

3. The method for preparing a perylene imide photothermal diagnostic and therapeutic agent according to claim 2, characterized in that: The preparation method also includes step (5), specifically: dissolving the PDI-5 in dimethyl sulfoxide, adding it dropwise into a PBS solution under an ultrasonic environment, washing with a PBS solution, and freeze-drying to obtain J-aggregated PDI-5.

4. The method for preparing a perylene imide photothermal diagnostic and therapeutic agent according to claim 2, characterized in that: The molar ratio of perylenetetracarboxylic dianhydride to Br2 in step (1) is 1:4 to 1:8; and / or Optionally, the molar ratio of PDI-2 to α-phenylethylamine in step (2) is 1:2 to 1:5; and / or Optionally, the molar ratio of PDI-3 to N-Boc-1,6-diaminohexane in step (3) is 1:2 to 1:10; and / or Optionally, the molar ratio of PDI-4 to boron tribromide in step (4) is 1:50 to 1:

100.

5. Use of the perylene imide photothermal diagnostic agent as claimed in claim 1 in the preparation of antibacterial medical materials.

6. An antibacterial hydrogel, characterized in that: The raw materials include the perylene imide photothermal diagnostic agent according to claim 1.

7. The antibacterial hydrogel according to claim 6, characterized in that: The hydrogel comprises the following raw materials: SR formed by self-assembly of NO donor BNN6 and the perylene imide photothermal diagnostic and therapeutic agent, F127 containing a formyl group, and hydroxypropyl chitosan containing an amino group; Wherein, the structural formula of BNN6 is: The structural formula of the F127 containing a formyl group is:

8. The antibacterial hydrogel according to claim 7, characterized in that: The preparation process of the SR is as follows: The BNN6 is mixed with a perylene imide photothermal diagnostic agent and self-assembled at 25° C. for 6 h to form a SR; Among them, the mass ratio of BNN6 and perylene imide photothermal therapeutic agent is 2:

5.

9. An antibacterial hydrogel according to claim 7 or 8, characterized in that: The hydrogel comprises the following raw materials, calculated by weight ratio: The mass ratio of F127 containing formyl group, hydroxypropyl chitosan containing amino group and SR is 50:20:

1.

10. A method for preparing an antibacterial hydrogel, characterized in that: The following steps are involved: SR is added to a PBS solution of hydroxypropyl chitosan containing amino groups to obtain a mixed solution, and then the mixed solution is mixed with a PBS solution of F127 containing formyl groups, and vortexed and ultrasonically treated in sequence to obtain the antibacterial hydrogel according to any one of claims 7 to 9.

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