Near-infrared two-region fluoroborondiazon dye molecule with high photo-thermal conversion efficiency and preparation method and application thereof

Abstract

The application provides a near-infrared two-region fluoroborondye molecule with high photo-thermal conversion efficiency and a preparation method thereof, wherein the fluoroborondye molecule BDF-8OMe is obtained by dissolving BDF-2Br and N1-(4-(bis(4-methoxyphenyl)amino)phenyl)-N4,N4-bis(4-methylphenyl)benzene-1,4-diamine (TPA-NH) in a toluene medium under a nitrogen atmosphere, using palladium acetate as a catalyst, tri-tert-butylphosphine tetrafluoroborate as a ligand, and cesium carbonate as an inorganic base. The fluoroborondye molecule has a D-A-D structure and has good absorption in the NIR-II region. The photo-thermal reagent prepared from the fluoroborondye molecule has a high photo-thermal conversion efficiency of 62.5% under 1064nm laser excitation, and can be used for precise and efficient NIR-II photoacoustic / photo-thermal imaging mediated photothermal therapy of deep tumor tissue, reduces tumor treatment damage and side effects, and improves treatment efficiency and accuracy.

Description

Technical Field

[0001] This invention relates to the field of biomaterials technology, and more specifically to a near-infrared II region fluoroboron methyl zirconia dye molecule with high photothermal conversion efficiency, its preparation method, and its applications. Background Technology

[0002] With the development of cancer therapeutics, NIR-II (1000-1700nm) lasers have greater penetration depth and higher maximum permissible exposure (e.g., 0.33W cm⁻¹ for an 808nm laser). -2 A 1064nm laser is 1.0W cm⁻¹ -2 Current research focuses more on the shift from excitation in the traditional NIR-I region (700-1000 nm) to excitation in the NIR-II region.

[0003] Currently, the development of NIR-II photothermal reagents mainly focuses on inorganic materials (such as gold nanoparticles, copper sulfide nanomaterials, quantum dots, etc.), organic conjugated polymers, and small molecule dyes. Although various NIR-II photothermal reagents based on inorganic materials have been developed, they still face drawbacks such as poor reproducibility and potential long-term biotoxicity. Semiconductor polymer molecules with long conjugated backbones often exhibit good absorbance and photothermal properties in the NIR-II region, but the uncertainty of molecular weight and molecular structure limits their application to the experimental research stage. In contrast, small dye molecules have rapid metabolism, well-defined structures, and high biocompatibility, making them more suitable for clinical translation. Currently, the development of small molecules absorbing in the NIR-II region is still concentrated on cyanine dyes, as their relatively long molecular conjugation and the introduction of heterocycles make it easier to extend the molecular absorption peak to the NIR-II region. However, due to limited molecular conjugation, complex synthesis, and lack of building blocks, small NIR-II absorbing molecules with donor-acceptor-donor (DAD) structures remain very scarce. Summary of the Invention

[0004] The purpose of this invention is to synthesize a fluoroboron methyl zirconia dye molecule with high photothermal conversion efficiency, to solve the problem of the scarcity and lack of diversity of small molecules that absorb NIR-II, and to improve the problem of insufficient tissue penetration in traditional tumor phototherapy, which makes it impossible to diagnose and treat tumors in deep locations.

[0005] According to a first aspect of the present invention, a near-infrared II fluoroboron methyl sulfonium dye molecule with high photothermal conversion efficiency is provided, the fluoroboron methyl sulfonium dye molecule being designated BDF-8OMe, and having a chemical structure as shown in Formula I:

[0006]

[0007] According to a second aspect of the present invention, a method for preparing the aforementioned near-infrared II fluoroboron methyl zanzium dye molecule with high photothermal conversion efficiency is provided, comprising the following steps:

[0008] Under a nitrogen atmosphere, BDF-2Br and N1-(4-(bis(4-methoxyphenyl)amino)phenyl)-N4,N4-bis(4-methylphenyl)benzene-1,4-diamine (TPA-NH) were dissolved in toluene medium. Palladium acetate was used as a catalyst, tri-tert-butylphosphine tetrafluoroborate was used as a ligand, and cesium carbonate was used as an inorganic base. The reaction was carried out under the desired reaction conditions to obtain the fluoroboron methyl benzoate dye molecule BDF-8OMe.

[0009] As an optional implementation, the molar ratio of BDF-2Br, TPA-NH, palladium acetate, tritert-butylphosphine tetrafluoroborate, and cesium carbonate is 1:(2-4):(0.05-0.15):(0.15-0.45):(6-8).

[0010] As an optional implementation method, the required reaction conditions are: reacting at a temperature of 80-110°C for 18-24 hours.

[0011] As an optional implementation, the preparation method further includes: after the reaction is completed, removing the solvent from the reaction mixture, and purifying the crude product by column chromatography to obtain a dark blue solid BDF-8OMe.

[0012] As an optional implementation, the method for removing the solvent from the reaction mixture is to extract the reaction mixture with dichloromethane and remove the solvent by vacuum distillation.

[0013] In a third aspect of the present invention, the use of the aforementioned near-infrared II fluoroboronium dye molecule with high photothermal conversion efficiency in the preparation of a photothermal reagent for NIR-II photoacoustic / photothermal imaging-mediated tumor photothermal therapy is provided.

[0014] In a fourth aspect of the present invention, a photothermal reagent prepared using the aforementioned near-infrared II fluoroboronium dye molecule with high photothermal conversion efficiency is provided.

[0015] As an optional implementation, the photothermal reagent is a nanoparticle prepared by self-assembly of BDF-8OMe and the amphiphilic polymer F127.

[0016] As an optional implementation, the photothermal reagent has a photothermal conversion efficiency of over 60% under 1064nm laser excitation.

[0017] As can be seen from the above technical solutions of the present invention, the near-infrared II fluoroboronium dye molecule with high photothermal conversion efficiency proposed in this invention has a DAD structure and exhibits good absorption in the NIR-II region. The nanoparticles prepared by self-assembly of the fluoroboronium dye molecule and the amphiphilic polymer F127 show a high photothermal conversion efficiency of 62.5% under 1064nm laser excitation. It can be used for precise and efficient NIR-II photoacoustic / photothermal imaging-mediated photothermal therapy of deep tumor tissues, reducing tumor treatment damage and side effects, and improving treatment efficiency and accuracy. As a novel NIR-II small molecule photothermal reagent, it has good application prospects in precision cancer diagnosis and treatment.

[0018] The fluoroboron methyl zirconia dye of the present invention has a well-defined molecular structure, a simple synthesis process, and low raw material cost. The nanoparticles prepared from this molecule have uniform particle size, good stability, and high NIR-II excitation photothermal conversion efficiency, which is higher than that of most small molecules that absorb NIR-II regions reported to date. Attached Figure Description

[0019] Figure 1 This is the synthesis reaction circuit diagram of BDF-8OMe of the present invention.

[0020] Figure 2 This is an example of the BDF-8OMe of the present invention. 1 H-NMR spectrum.

[0021] Figure 3 This is an example of the BDF-8OMe of the present invention. 13 C-NMR spectrum.

[0022] Figure 4 This is the mass spectrum of BDF-8OMe as an example of the present invention.

[0023] Figure 5 This is a dynamic light scattering particle size distribution test diagram of BDF-8OMe nanoparticles as an example of the present invention.

[0024] Figure 6 This is the ultraviolet absorption spectrum of the BDF-8OMe nanoparticles in water, as exemplified by this invention.

[0025] Figure 7 This is a fitting curve of the photothermal conversion efficiency of BDF-8OMe nanoparticles as an example of the present invention.

[0026] Figure 8 The relative survival rates of mouse breast cancer cells (4T1) after 24 hours of incubation with different concentrations of BDF-8OMe nanoparticles under light or dark conditions.

[0027] Figure 9This is an NIR-II photoacoustic image of BDF-8OMe nanoparticles, an example of the present invention, in a mouse model of breast cancer.

[0028] Figure 10 This is a photothermal imaging image of BDF-8OMe nanoparticles in a breast cancer model mouse tumor site, as an example of the present invention.

[0029] Figure 11 This is a graph showing the changes in tumor volume during 14 days of treatment in a mouse model of breast cancer. Detailed Implementation

[0030] To better understand the technical content of the present invention, specific embodiments are described below in conjunction with the accompanying drawings.

[0031] Various aspects of the invention are described in this disclosure with reference to the accompanying drawings, in which numerous illustrative embodiments are shown. The embodiments of this disclosure are not necessarily intended to encompass all aspects of the invention. It should be understood that the various concepts and embodiments described above, as well as those described below in more detail, can be implemented in any of a number of ways.

[0032] Near-infrared II fluoroboronium dye molecules with high photothermal conversion efficiency

[0033] In an exemplary embodiment of the present invention, a near-infrared II fluoroboron methyl sulfonium dye molecule with high photothermal conversion efficiency is provided. This fluoroboron methyl sulfonium dye molecule is designated BDF-8OMe, and its chemical structure is shown in Formula I:

[0034]

[0035] The boron methyl zirconia dye molecules in the aforementioned examples have a donor-acceptor-donor (DAD) structure and exhibit good absorption in the NIR-II region.

[0036] Preparation method

[0037] Combination Figure 1 As shown, the exemplary method for preparing near-infrared II fluoroboron methyl benzoate dye molecules with high photothermal conversion efficiency of the present invention uses BDF-2Br, N1-(4-(bis(4-methoxyphenyl)amino)phenyl)-N4,N4-bis(4-methylphenyl)phenyl-1,4-diamine, palladium acetate, tri-tert-butylphosphine tetrafluoroborate, and cesium carbonate as raw materials, according to... Figure 1 The reaction is prepared using the reaction route described above.

[0038] As an optional example, the preparation method specifically includes the following steps:

[0039] Under a nitrogen atmosphere, BDF-2Br and N1-(4-(bis(4-methoxyphenyl)amino)phenyl)-N4,N4-bis(4-methylphenyl)benzene-1,4-diamine (TPA-NH) were dissolved in toluene medium. Palladium acetate was used as a catalyst, tri-tert-butylphosphine tetrafluoroborate was used as a ligand, and cesium carbonate was used as an inorganic base. The reaction was carried out under the desired reaction conditions to obtain the fluoroboron methyl benzoate dye molecule BDF-8OMe.

[0040] As an optional example, the molar ratio of BDF-2Br, TPA-NH, palladium acetate, tri-tert-butylphosphine tetrafluoroborate, and cesium carbonate is 1:(2-4):(0.05-0.15):(0.15-0.45):(6-8).

[0041] As an optional example, the required reaction conditions are: reacting at a temperature of 80-110℃ for 18-24 hours.

[0042] As an optional example, the preparation method further includes: after the reaction is completed, removing the solvent from the reaction mixture, and purifying the crude product by column chromatography to obtain a dark blue solid BDF-8OMe.

[0043] As an optional implementation, the method for removing the solvent from the reaction mixture is to extract the reaction mixture with dichloromethane and remove the solvent by vacuum distillation.

[0044] In another exemplary embodiment of the present invention, the application of the aforementioned near-infrared II fluoroboronium dye molecule with high photothermal conversion efficiency is also provided in the preparation of photothermal reagents for NIR-II photoacoustic / photothermal imaging-mediated tumor photothermal therapy.

[0045] In another exemplary embodiment of the present invention, a photothermal reagent prepared using the aforementioned near-infrared II fluoroboronium dye molecule with high photothermal conversion efficiency is also provided.

[0046] In a preferred embodiment, the photothermal reagent is nanoparticles prepared by self-assembly of BDF-8OMe and the amphiphilic polymer F127.

[0047] In a preferred embodiment, the photothermal conversion efficiency of the photothermal reagent under 1064nm laser excitation is above 60%.

[0048] The photothermal agent prepared using the aforementioned near-infrared II fluoroboronium dye molecule with high photothermal conversion efficiency exhibits a high photothermal conversion efficiency of 62.5% under 1064nm laser excitation. It can be applied to precise and efficient NIR-II photoacoustic / photothermal imaging-mediated photothermal therapy for deep tumor tissues, reducing tumor treatment damage and side effects, and improving treatment efficiency and accuracy.

[0049] To facilitate better understanding, the present invention will be further illustrated below with several specific examples, but the preparation process is not limited to these examples, and the content of the present invention is not limited to these examples.

[0050] Unless otherwise specified, the materials in the examples are prepared according to existing methods or purchased directly from the market.

[0051] Example 1

[0052] [Synthesis of BDF-8OMe]

[0053] In a dry 250 mL double-necked flask, BDF-2Br (227.43 mg, 0.5 mmol), N1-(4-(bis(4-methoxyphenyl)amino)phenyl)-N4,N4-bis(4-methylphenyl)benzene-1,4-diamine (935.63 mg, 1.5 mmol), palladium acetate (11.2 mg, 0.05 mmol), tri-tert-butylphosphine tetrafluoroborate (43.5 mg, 0.15 mmol), cesium carbonate (1140 mg, 3.5 mmol), and anhydrous dry toluene (30 mL) were added. The mixture was heated to 110 °C in the dark under a nitrogen atmosphere and reacted for 20 hours. After cooling to room temperature, the reaction mixture was extracted with dichloromethane, and the solvent was removed by vacuum distillation. The crude product was purified by column chromatography (silica, dichloromethane: petroleum ether = 4:1) to give a dark blue solid BDF-8OMe (110 mg, 14.3%).

[0054] like Figure 2 As shown, 1 H NMR (400MHz, CDCl3): δppm 7.72 (d, J = 8.8Hz, 4H), 7.07 (d, J = 8.9Hz, 16H), 6.95 (t, J = 10.0Hz, 12H), 6.85 (dd, J = 11.7, 8.9Hz, 24H), 3.79 (s, 24H).

[0055] like Figure 3 As shown, 13 C NMR (100MHz, CDCl3): δppm 156.00,150.43,146.22,140.80,138.29,126.96,126.67,124.04,121.21,119.01,115.51,114.82,100.00,55.61.

[0056] like Figure 4 As shown, MALDI-TOF mass spectrometry (m / z): calcd for C 94 H 80 BF2N 11 O8[M]+ :1539.6252; found,1540.0940.

[0057] Combination Figure 2-4 As shown, the molecular structure of BDF-8OMe can be determined to be Formula I.

[0058]

[0059] Example 2

[0060] [Preparation of BDF-8OMe Nanoparticles]

[0061] BDF-8OMe nanoparticles were prepared via a nanoprecipitation method, as detailed below:

[0062] BDF-8OMe molecules (1 mg) (prepared according to the method of Example 1) and Pluronic F-127 (10 mg) were dissolved in tetrahydrofuran (1 mL) and sonicated for 5 minutes.

[0063] Then, the solution was quickly injected into deionized water (10 mL) and sonicated for 1 hour. After stirring and evaporating to completely remove tetrahydrofuran, it was filtered with a 0.22 μm filter to obtain a clear and transparent dark blue BDF-8OMe nanoparticle solution, which was stored at 4 °C for later use.

[0064] like Figure 5 As shown, the dynamic light scattering particle size distribution test results of BDF-8OMe nanoparticles show that their hydrated particle size is 80 nm, which meets the requirements of enhanced permeability and retention (EPR) effect.

[0065] like Figure 6 As shown, BDF-8OMe nanoparticles have a maximum absorption peak of 903 nm in water, and the tail of the absorption peak extends to 1300 nm.

[0066] Example 3

[0067] [Photothermal Performance Test of BDF-8OMe Nanoparticles]

[0068] Using a 1064nm laser (1W cm) -2 Irradiate BDF-8OMe nanoparticle aqueous solution (1 mL, 100 μg / mL) and deionized water (1 mL), heat for 10 minutes and then cool naturally for 15 minutes to return to room temperature. Calculate the photothermal conversion efficiency of the BDF-8OMe nanoparticle aqueous solution using the cooling period.

[0069] like Figure 7As shown, the photothermal conversion efficiency of the BDF-8OMe nanoparticle aqueous solution of the present invention is 62.5%.

[0070] Example 4

[0071] [Cytotoxicity assay of BDF-8OMe nanoparticles]

[0072] 4T1 cells were loaded at 5.0 × 10⁶ cells per well. 3 Two 96-well plates were seeded at different densities and incubated at 37°C in a dark environment with 5% CO2 for 24 hours. Different concentrations of BDF-8OMe nanoparticles (0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50 μg / mL) were then added. -1 Add to the well plate and incubate for 12 hours.

[0073] After incubation for 12 hours, the sample was subjected to a 1064nm laser (1W cm⁻¹) at room temperature. -2 One well of the plate was irradiated for 5 minutes per well, while the other well was incubated in the dark to test the cytotoxicity of BDF-8OMe nanoparticles.

[0074] After illumination, the wells were incubated in darkness for 12 hours. Then, 200 μL of MTT solution was added to each well, and the cells were incubated in darkness for 4 hours. The culture medium was removed, and 200 μL of dimethyl sulfoxide was added to dissolve the blue-purple formazan crystals. The absorbance at 490 nm was read using a microplate reader, and the viability of 4T1 cells under different concentrations of BDF-8OMe nanoparticles was calculated. The cell viability was calculated as: (Average absorbance of the treatment group / Average absorbance of the control group) × 100%.

[0075] like Figure 8 As shown, even under low light conditions, the concentration of BDF-8OMe nanoparticles is as high as 50 μg / mL. -1 The survival rate of 4T1 cells remained above 90%; however, under light conditions, only 35 μg / mL... -1 BDF-8OMe nanoparticles can kill nearly 90% of 4T1 cells.

[0076] Example 5

[0077] [NIR-II photoacoustic imaging of BDF-8OMe nanoparticles in mice]

[0078] BDF-8OMe nanoparticles (200 μL, 500 μg mL) were added. -1 The tumor was injected into mice via the tail vein, and photoacoustic images of the tumor site were recorded at different time points (pre, 2, 4, 6, 8, 12, and 18 hours before injection).

[0079] like Figure 9 As shown, after intravenous injection of BDF-8OMe nanoparticles into mice, the photoacoustic signal at the tumor site gradually increased over time, reaching a maximum value at 8 hours, and then gradually weakened.

[0080] Example 6

[0081] [In vivo photothermal imaging of BDF-8OMe nanoparticles in mice]

[0082] BDF-8OMe nanoparticles (100 μL, 500 μg mL) were added. -1 ) or PBS buffer (100 μL) was injected into mice via the tail vein, and photothermal images of the tumor site were recorded at different time points (0, 1, 2, 3, 4, 5 minutes). Figure 10 As shown.

[0083] Example 7

[0084] [Tumor Therapy Experiment with BDF-8OMe Nanoparticles]

[0085] 4T1 tumor-bearing mouse models were established by subcutaneous injection of 4T1 cancer cells until the tumor volume reached 50 mm. 3 After moving left and right, subsequent experiments can be conducted.

[0086] 4T1 tumor-bearing mice were randomly divided into four groups (PBS, PBS+L, NPs, and NPs+L, n=5 per group, where L represents laser irradiation). Mice in the PBS and PBS+L groups were intravenously injected with PBS (100 μL), while mice in the NPs and NPs+L groups were intravenously injected with BDF-8OMe nanoparticles (100 μL, 500 μg / mL). -1 Six hours after injection, the tumor sites of mice in the PBS+L group and NPs+L group were treated with a 1064nm laser (1W cm⁻¹). -2 Irradiate for 5 minutes. After one treatment, the tumor size is measured every 2 days until day 14.

[0087] like Figure 11 As shown, after one treatment, the tumors in the NPs+L group were completely eliminated on the 4th day after treatment and there was no recurrence within 14 days, while the tumor volume in the PBS group, PBS+L group and NPs group increased by 7 to 8 times on the 14th day after treatment.

[0088] The above tests demonstrate that the photothermal reagent prepared from the fluoroboron methyl zirconia dye molecules of this invention can be used for precise and efficient NIR-II photoacoustic / photothermal imaging-mediated photothermal therapy of deep tumor tissues, reducing tumor treatment damage and side effects, and improving treatment efficiency and accuracy.

[0089] While the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Those skilled in the art can make various modifications and refinements without departing from the spirit and scope of the invention. Therefore, the scope of protection of the present invention shall be determined by the claims.

Claims

1. A near-infrared II region fluoroboron methyl zanzium dye molecule with high photothermal conversion efficiency, characterized in that, The fluoroboron formazan dye molecule is designated BDF-8OMe, and its chemical structure is shown in Formula I: Formula I.

2. A method for preparing a near-infrared II fluoroboronium dye molecule with high photothermal conversion efficiency as described in claim 1, characterized in that, Includes the following steps: Under a nitrogen atmosphere, BDF-2Br and TPA-NH are dissolved in toluene medium, with palladium acetate as catalyst, tri-tert-butylphosphine tetrafluoroborate as ligand, and cesium carbonate as inorganic base. The reaction is carried out under the required reaction conditions to obtain the fluoroboron methyl sulfonium dye molecule BDF-8OMe. The chemical structural formula of BDF-2Br is shown in Formula II: Formula II; The chemical structural formula of TPA-NH is shown in Formula III: Formula III.

3. The preparation method according to claim 2, characterized in that, The molar ratio of BDF-2Br, TPA-NH, palladium acetate, tritert-butylphosphine tetrafluoroborate, and cesium carbonate is 1:(2-4):(0.05-0.15):(0.15-0.45):(6-8).

4. The preparation method according to claim 2, characterized in that, The required reaction conditions are: react at 80-110℃ for 18-24 h.

5. The preparation method according to claim 2, characterized in that, The preparation method further includes: after the reaction is completed, removing the solvent from the reaction mixture, and purifying the crude product by column chromatography to obtain a dark blue solid BDF-8OMe.

6. The preparation method according to claim 5, characterized in that, The method for removing solvent from the reaction mixture is as follows: extract the reaction mixture with dichloromethane and remove the solvent by vacuum distillation.

7. The use of the near-infrared II fluoroboronium dye molecule with high photothermal conversion efficiency as described in claim 1 in the preparation of a photothermal reagent for NIR-II photoacoustic / photothermal imaging-mediated tumor photothermal therapy.

8. A photothermal reagent prepared using the near-infrared II fluoroboronium dye molecule with high photothermal conversion efficiency as described in claim 1.

9. The photothermal reagent according to claim 8, characterized in that, The photothermal reagent is a nanoparticle prepared by self-assembly of BDF-8OMe and the amphiphilic polymer F127.

10. The photothermal reagent according to claim 8, characterized in that, The photothermal reagent has a photothermal conversion efficiency of over 60% under 1064 nm laser excitation.

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