Imidazolyl dimeric acceptor and preparation method thereof, photoelectric detector and biological phototherapy and diagnosis nanoparticles

Abstract

The application discloses an imidazole-based dimeric acceptor, a preparation method thereof, a photoelectric detector and a biological phototherapy and diagnosis nanoparticle. A general structural formula of the imidazole-based dimeric acceptor is shown in the following formula: wherein R1 is R2 is X1 and X2 are independently selected from H, F, Cl, Br, I, NO2, CF3, CH3 or OCH3, Y is selected from one of C1-C10 alkane chains, and n is 0, 1, 2, 3, 4, 5 or 6.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of organic photoelectric functional materials, and particularly relates to an imidazole-based dimeric acceptor and a preparation method thereof, a photoelectric detector and a biological photodiagnosis and treatment nanoparticle. BACKGROUND

[0002] Organic photoelectric materials have attracted extensive attention due to their multifunctionality, and can be applied to the fields of solar cells, organic photoelectric detectors, light-emitting diodes, transistors, biological photodiagnosis and treatment, and photocatalysis. Among them, organic photoelectric detectors are known for their mechanical flexibility, making them suitable for flexible electronic products and wearable devices. They have a wide spectral response, enabling them to cover a wide range of spectrum, and some models have a fast response time, which is very suitable for high-speed response device applications. In addition, organic photoelectric detectors are environmentally friendly and can be integrated with other organic electronic components to form a fully organic flexible system. In addition, photodiagnosis as a new diagnosis and treatment mode can realize synergistic disease diagnosis and treatment under the excitation of light, and has the advantages of non-invasiveness, spatiotemporal selectivity, high efficiency and small side effects. Photodynamic therapy among them has made remarkable progress in the medical field, especially in the treatment of tumors, and it has become the fourth treatment method in addition to surgery, radiotherapy and chemotherapy. Photosensitizers play a crucial role as light conversion media. Organic photoelectric materials have excellent application effects in fluorescence imaging guided photodynamic therapy due to their unique optical properties and good biocompatibility, low toxicity and high structural diversity.

[0003] A dimer is a specific molecule composed of two identical units, which combines the characteristics of small molecules and polymers. This includes a clear molecular structure, precise molecular weight, excellent batch repeatability, and good solution processing performance. However, due to the limited number and variety of dimeric acceptors, most current dimeric acceptors are based on perylene imides and A-D-A type non-fullerene acceptors represented by Y6. For the former, although it has good planarity, which gives it a clear advantage in charge transport, the spectral absorption of this type of compound is relatively blue-shifted, and the poor light absorption ability limits its development due to insufficient utilization of sunlight. For the latter, although progress has been made in near-infrared absorption and effective improvement of the stability of organic solar cells, the absorption is still not red-shifted enough, limiting its further development in the fields of organic photoelectric detectors and biological photodiagnosis and treatment. In addition, the mainstream A-D-A type dimeric acceptors have reduced charge transport performance due to the fact that the indenone end group at the bridging unit does not participate in stacking.

[0004] Therefore, the prior art still needs to be improved and innovated. SUMMARY

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide an imidazole-based dimer receptor and its preparation method, as well as a photodetector and biophototherapy nanoparticles, aiming to solve the problem of poor charge transport capability of existing dimer receptors.

[0006] The technical solution of the present invention is as follows:

[0007] In a first aspect, the present invention provides an imidazole-based dimeric receptor, wherein the general structural formula of the imidazole-based dimeric receptor is:

[0008] Where R1 is R2 is X1 and X2 are independently selected from H, F, Cl, Br, I, NO2, CF3, CH3 or OCH3, Y is selected from one of the C1-C10 alkane chains, and n is 0, 1, 2, 3, 4, 5 or 6.

[0009] Preferably, the imidazole dimer receptor has one of the following structural formulas:

[0010]

[0011] A second aspect of the present invention provides a method for preparing an imidazole dimer receptor, such as... Figure 1 As shown, the preparation method includes the following steps:

[0012] Will The first reactant and the first reaction solvent are mixed and stirred at a first temperature for a first time to obtain the structure with the following formula: The first product of the reaction;

[0013] The first reaction product was mixed with the second reactant, the third reactant, and the second reaction solvent, and stirred at a second temperature for a second time to obtain the structure with the following formula: The second reaction product;

[0014] The second reaction product and The fourth reactant and the third reaction solvent are mixed and stirred at a third temperature for a third time to obtain the imidazole dimer receptor;

[0015] Wherein, the first reactant is sodium tert-butoxide, potassium tert-butoxide, sodium hydride, or potassium carbonate; the second reactant is N,N-dimethylformamide; the third reactant is phosphorus oxychloride or phosphorus oxybromide; and the fourth reactant is pyridine, piperidine, or sodium tert-butoxide. The first reaction solvent is N,N-dimethylformamide, dimethyl sulfoxide, or N-methylpyrrolidone; the second reaction solvent is 1,2-dichloroethane, dichloromethane, or chloroform; and the third reaction solvent is chloroform, dichloromethane, 1,2-dichloroethane, or tetrahydrofuran.

[0016] Preferably, the first reaction product is mixed with the second reaction material and the third reaction material in a molar ratio of 1:(2-10):(2-10). The molar ratio of the first reaction material to the second reaction material is 2:1:(2-10).

[0017] The first temperature is 80-100℃, and the first time is 12-24h.

[0018] Preferably, the first reaction product is mixed with the second reaction material and the third reaction material in a molar ratio of 1:(2-10):(2-10).

[0019] The second temperature is 80-100℃, and the second time is 10-24h.

[0020] Preferably, the second reaction product is mixed with the third reaction material in a molar ratio of 1:4:(10-100).

[0021] The third temperature is 60-80℃, and the third time is 12-24h.

[0022] In a third aspect of the present application, a photodetector is provided, which comprises the imidazolyl dimeric acceptor as described above.

[0023] Preferably, the photodetector comprises a substrate and an imidazolyl dimeric acceptor thin film deposited on the substrate, wherein the imidazolyl dimeric acceptor thin film is prepared by mixing the imidazolyl dimeric acceptor as described above with a polymer donor and then depositing the mixture on the substrate.

[0024] In a fourth aspect of the present application, a biological photodiagnosis and treatment nanoparticle is provided, which comprises the imidazolyl dimeric acceptor as described above.

[0025] Preferably, the biological photodiagnosis and treatment nanoparticle is obtained by wrapping the imidazolyl dimeric acceptor as described above with hydrophilic polyethylene glycol.

[0026] Beneficial effects: The present application provides an imidazolyl dimeric acceptor, a preparation method thereof, a photodetector, and a biological photodiagnosis and treatment nanoparticle. Compared with monomer small molecules, the imidazolyl dimeric acceptor provided by the present application has stronger intramolecular charge transfer, lower LUMO and HOMO energy levels, which is conducive to the separation of excitons at the acceptor interface, thereby increasing the current of the system. Moreover, the photodetector device prepared based on the imidazolyl dimeric acceptor has a higher external quantum efficiency value than the photodetector device based on monomer small molecules, which indicates that the dimeric acceptor has better packing, thereby resulting in better charge transport. In addition, the dark current of the dimeric acceptor device is also significantly lower than that of the monomer small molecule device, which leads to a significantly higher specific detectivity value in the dimeric acceptor device, which indicates that the imidazolyl dimeric acceptor is a good photodetector material.

[0027] ​Furthermore, existing dimer acceptors are based on perylene imide and ADA-type non-fullerene acceptors represented by Y6. For the former, the spectral absorption of these compounds exhibits a significant blue shift, resulting in poor light absorption and insufficient utilization of sunlight, thus limiting their development. For the latter, although some progress has been made in near-infrared absorption and the stability of organic solar cells has been effectively improved, its absorption still lacks a sufficient red shift, limiting its further development in organic photodetectors and biophototherapy. The imidazole-based dimer acceptor provided by this invention effectively overcomes these shortcomings. In addition, the charge transport performance of currently mainstream ADA-type dimer acceptors is reduced because the indanone end groups at the bridging units do not participate in stacking. However, the imidazole-based dimer acceptor provided by this invention connects the central cores through flexible alkyl chains, thus retaining the indanone end groups with strong electron transport capabilities, thereby achieving efficient charge transport. Attached Figure Description

[0028] Figure 1 The synthetic route for the imidazole dimer receptor provided in the embodiments of the present invention;

[0029] Figure 2 The absorption spectra of H2-C4 prepared in Example 1, H2-C8 prepared in Example 3, and H0 prepared in Comparative Example 1 in dilute chloroform solution.

[0030] Figure 3 Absorption spectra of H2-C4 prepared in Example 1, H2-C8 prepared in Example 3, and H0 prepared in Comparative Example 1 in thin films;

[0031] Figure 4 Electrochemical cyclic voltammetry curves of H2-C4 prepared in Example 1, H2-C8 prepared in Example 3, and H0 prepared in Comparative Example 1.

[0032] Figure 5 External quantum efficiency curves of H2-C4 prepared in Example 1, H2-C8 prepared in Example 3, and H0 prepared in Comparative Example 1 are shown.

[0033] Figure 6 Dark current curves of H2-C4 prepared in Example 1, H2-C8 prepared in Example 3, and H0 prepared in Comparative Example 1 are shown.

[0034] Figure 7 The specific detectivity curves of H2-C4 prepared in Example 1, H2-C8 prepared in Example 3, and H0 prepared in Comparative Example 1 are shown.

[0035] Figure 8Fluorescence imaging images of H1 prepared for the present comparative example 2, H2-C6 prepared for example 2 and H2-C6O2 prepared for example 4;

[0036] Figure 9 Photodynamic therapy images of H1 prepared for the present comparative example 2, H2-C6 prepared for example 2 and H2-C6O2 prepared for example 4;

[0037] Figure 10 Fluorescence imaging images of mice of H1 prepared for the present comparative example 2, H2-C6 prepared for example 2 and H2-C6O2 prepared for example 4;

[0038] Figure 11 Photodynamic therapy images of mice of the receptor material mentioned in example 8. DETAILED DESCRIPTION

[0039] The present application provides an imidazole-based dimeric receptor, a preparation method thereof, a photodetector and a biophototherapy nanoparticle. To make the purpose, technical scheme and effects of the present application more clear and explicit, the present application is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application.

[0040] The present application provides an imidazole-based dimeric receptor, a preparation method thereof, a photodetector and a biophototherapy nanoparticle. To make the purpose, technical scheme and effects of the present application more clear and explicit, the present application is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application.

[0041] wherein R1 is R2 is X1 and X2 are independently selected from H, F, Cl, Br, I, NO2, CF3, CH3 or OCH3, Y is selected from one of C1-C10 alkyl chain, and n is 0, 1, 2, 3, 4, 5 or 6.

[0042] Compared with the prior art, the present application can realize efficient electron transfer between end groups by retaining the indenone end group. Secondly, the present application adopts a flexible connection mode with the center core head-to-head, which can effectively adjust the accumulation of molecules, thereby further facilitating charge transport. By changing different functional groups of the end group and the length of the alkyl chain, the performance can be visualized and controlled.

[0043] In some embodiments, the imidazole-based dimeric receptor has the general structure of:

[0044]

[0045] wherein R1 is R2 is X1 and X2 are independently selected from H, F, Cl, Br, I, NO2, CF3, CH3 or OCH3, Y is selected from one of the C1-C10 alkane chains, and n is 0, 1, 2, 3, 4, 5 or 6.

[0046] In some embodiments, the imidazole dimer receptor has one of the following structural formulas:

[0047] In some embodiments, the preparation method includes the following steps:

[0048] Will The first reactant is mixed with the first reaction solvent and stirred at the first temperature for the first time to obtain the first reactant;

[0049] The first reactant, the second reactant, the third reactant, and the second reaction solvent were mixed and stirred at a second temperature for a second time to obtain the structure with the following formula: The second reactant;

[0050] The second reactant and The fourth reactant and the third reaction solvent are mixed and stirred at a third temperature for a third time to obtain the imidazole dimer receptor;

[0051] Wherein, the first reactant is sodium tert-butoxide, potassium tert-butoxide, sodium hydride, or potassium carbonate; the second reactant is N,N-dimethylformamide; the third reactant is phosphorus oxychloride or phosphorus oxybromide; and the fourth reactant is pyridine, piperidine, or sodium tert-butoxide. The first reaction solvent is N,N-dimethylformamide, dimethyl sulfoxide, or N-methylpyrrolidone; the second reaction solvent is 1,2-dichloroethane, dichloromethane, or chloroform; and the third reaction solvent is chloroform, dichloromethane, 1,2-dichloroethane, or tetrahydrofuran.

[0052] In some embodiments, the first temperature is 80-100°C, the first time is 12-24h, the second temperature is 80-100°C, the second time is 10-24h, the third temperature is 60-80°C, and the third time is 12-24h.

[0053] In some embodiments, the imidazole dimer receptor has the following structural formula:

[0054] Insert a Z segment between the two segments, where the Z segment can be... Fragments that can be used for connection. R1 is... R2 is X1and X2are independently selected from H, F, Cl, Br, I, NO2, CF3, CH3or OCH3, Y is selected from one of C1-C10 alkyl chain, and n is 0, 1, 2, 3, 4, 5 or 6.

[0055] In some embodiments, the molecular formula of the imidazolyl dimeric acceptor is as follows: wherein R1and R2are interchangeable.

[0056] In a third aspect of the present application, a photodetector is provided, which comprises the imidazolyl dimeric acceptor as described above.

[0057] In some embodiments, the photodetector comprises a substrate and an imidazolyl dimeric acceptor thin film deposited on the substrate, wherein the imidazolyl dimeric acceptor thin film is prepared by mixing the imidazolyl dimeric acceptor as described above with a polymer donor and then depositing the mixture on the substrate.

[0058] In a fourth aspect of the present application, a biological photodiagnosis and treatment nanoparticle is provided, which comprises the imidazolyl dimeric acceptor as described above.

[0059] In some embodiments, the biological photodiagnosis and treatment nanoparticle is obtained by wrapping the imidazolyl dimeric acceptor as described above with hydrophilic polyethylene glycol.

[0060] The technical solutions in the embodiments of the present application will be described clearly and completely below. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments of the present application, which are only used to illustrate the present application and by no means limit the present application. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without any creative work fall within the scope of protection of the present application.

[0061] Embodiment 1

[0062] The preparation of the imidazolyl dimeric acceptor comprises the following steps:

[0063] (1) Synthesis of DBM-C4, the synthesis route of which is as follows:

[0064]

[0065] BM (600 mg) and 1,4-dibromobutane (55 mg) were added to a dried round bottom flask equipped with a magnetic stir bar. After vacuum and backfilling with argon three times, DMF (N,N-dimethylformamide) 30 mL and sodium tert-butoxide 300 mg were added to the round bottom flask in this order. The above reaction mixture was stirred at 80 °C for 12 hours, after cooling to room temperature, poured into 150 mL of water, and extracted with ethyl acetate. After washing the organic layer with brine, drying with anhydrous magnesium sulfate, filtering, and drying the filtrate, a sticky solid DBM-C4 was obtained. The solid was used directly for the next reaction after being separated by a chromatography column as a crude product.

[0066] (2) Synthesis of DBMCHO-C4, whose synthetic route is as follows:

[0067]

[0068] The above crude product DBM-C4 was added to a dried round bottom flask equipped with a magnetic stir bar. After vacuum and backfilling with argon three times, 1,2-dichloroethane (20 mL), DMF (5 mL), and phosphorus oxychloride (1 mL) were added to the round bottom flask in this order. The above reaction mixture was stirred at 80 °C for 10 hours, after cooling to room temperature, poured into 150 mL of water, and extracted with dichloromethane. After washing the organic layer with brine, drying with anhydrous magnesium sulfate, filtering, and drying the filtrate, a yellow solid was obtained. The solid was further purified by silica gel column chromatography (petroleum ether: dichloromethane = 1:1 to 2:1) to obtain DBMCHO-C4 as a yellow solid (120.0 mg, 19.6% yield over two steps).

[0069] 1 H NMR (400 MHz, CDC13) δ: 0.54-0.71 (m, 36H); 0.80-0.89 (m, 28H);

[0070] 0.91-1.04 (m, 28H); 1.19-1.31 (m, 58H); 1.36-1.48 (m, 12H); 1.80-1.96 (m, 14H); 2.20-2.35 (m, 4H); 2.70 (s, 6H); 3.05-3.21 (m, 8H); 4.53-4.69 (m, 12H); 10.11-10.14 (m, 4H).

[0071] (3) Synthesis of H2-C4, whose synthetic route is as follows:

[0072]

[0073] The resulting DBMCHO-C4 (120 mg) and IC-C1 (200 mg) were added to a dried round bottom flask equipped with a magnetic stir bar. After vacuum and backfilling with argon three times, chloroform (30 mL) and pyridine (0.6 mL) were added to the round bottom flask in sequence. The above reaction mixture was stirred at 60 °C for 12 hours, after cooling to room temperature, the reaction mixture was concentrated to about 10 mL and methanol (100 mL) was added. After filtration, the resulting solid was further purified by flash silica gel column chromatography (petroleum ether: dichloromethane = 1 : 1 to 2: 1) to obtain black solid H2-C4 (140 mg, yield 77.0%).

[0074] 1 H NMR (400 MHz, CDC13) δ: 0.71-0.78 (m, 28); 0.80-0.90 (m, 24H); 0.99-1.17 (m, 72H); 1.27-1.30 (m, 28H); 1.38-1.43 (m, 8H); 1.51-1.57 (m, 12H); 1.87-1.94 (m, 4H); 2.03 (m, 2H); 2.12-2.14 (m, 2H); 2.29 (s, 4H); 2.88 (s, 6H); 3.25-3.29 (m, 4H), 4.63 (s, 4H); 4.77 (s, 4H); 4.90 (s, 4H); 7.67 (s, 2H); 7.99 (s, 2H); 8.53 (s, 2H); 8.81 (s, 2H); 8.92 (s, 2H); 9.21 (s, 2H).

[0075] Example 2

[0076] Preparation of imidazolyl dimeric acceptor, comprising the following steps:

[0077] (1) Synthesis of DBM-C6, whose synthetic route is as follows:

[0078]

[0079] BM (540 mg) and 1,6-dibromobutane (60 mg) were added to a dried round bottom flask equipped with a magnetic stir bar. After vacuum and backfilling with argon three times, DMF (N, N-dimethylformamide) 30 mL and sodium tert-butoxide 300 mg were added to the round bottom flask in sequence. The above reaction mixture was stirred at 80 °C for 12 hours, after cooling to room temperature, poured into 150 mL of water, and extracted with ethyl acetate. After washing the organic layer with brine, drying with anhydrous magnesium sulfate, filtering, and rotary evaporation of the filtrate, a viscous solid DBM-C6 was obtained. The solid was a crude product, which was directly used in the next step reaction after being separated by column chromatography.

[0080] (2) Synthesis of DBMCHO-C6, whose synthetic route is as follows:

[0081]

[0082] The above crude product DBM-C6 was added to a dried round-bottom flask equipped with a magnetic stir bar. After vacuum and backfilling with argon 3 times, 1,2-dichloroethane (20 mL), DMF (5 mL), and phosphorus oxychloride (1 mL) were added to the round-bottom flask in this order. The above reaction mixture was stirred at 80 °C for 10 hours, and after cooling to room temperature, it was poured into 150 mL of water and extracted with dichloromethane. The organic layer was washed with brine, dried over anhydrous magnesium sulfate, filtered, and the filtrate was rotary evaporated to give a yellow solid. The solid was further purified by silica gel column chromatography (petroleum ether: dichloromethane = 1:1 to 2:1) to give DBMCHO-C6 as a yellow solid (160.0 mg, 27.2% yield over two steps).

[0083] 1 H NMR (400 MHz, CDC13) δ: 0.47-0.57 (m, 16H); 0.61-0.68 (m, 16H); 0.80-0.88 (m, 38H); 0.93-0.97 (m, 24H); 1.20-1.48 (m, 70H); 1.53-1.56 (m, 4H); 1.80-1.94 (m, 12H); 1.97-2.01 (m, 4H); 2.68 (s, 6H); 3.01-3.19 (m, 8H); 4.53-4.60 (m, 12H); 10.08-10.11 (d, 4H).

[0084] (3) Synthesis of H2-C6, whose synthetic route is as follows:

[0085]

[0086] The resulting DBMCHO-C6 (80 mg) and IC-Cl (80 mg) were added to a dried round-bottom flask equipped with a magnetic stir bar. After vacuum and backfilling with argon 3 times, chloroform (20 mL) and pyridine (0.5 mL) were added to the round-bottom flask in this order. The above reaction mixture was stirred at 60 °C for 12 hours, and after cooling to room temperature, the reaction mixture was concentrated to about 10 mL and methanol (100 mL) was added. The resulting solid was further purified by flash silica gel column chromatography (petroleum ether: dichloromethane = 1:1 to 2:1) to give H2-C6 as a black solid (60 mg, 52.9% yield).

[0087] 1H NMR (400 MHz, CDC13) δ: 0.69 (m, 22H); 0.78-0.81 (m, 18H); 0.86-1.19 (m, 80H); 1.27-1.28 (m, 32H); 1.37-1.39 (m, 8H); 1.48-1.58 (m, 8H); 1.87-1.95 (m, 8H); 2.03 (s, 4H); 2.13 (s, 4H); 2.24 (s, 4H); 2.81 (s, 6H); 3.24-3.28 (m, 4H); 4.60 (s, 4H); 4.77 (s, 4H); 4.94 (s, 4H); 7.33 (s, 2H); 7.98 (s, 2H); 8.75 (s, 2H); 8.80-8.81 (d, 4H); 9.20 (s, 2H).

[0088] 3.24-3.28 (m, 4H); 4.60 (s, 4H); 4.77 (s, 4H); 4.94 (s, 4H); 7.33 (s, 2H); 7.98 (s, 2H); 8.75 (s, 2H); 8.80-8.81 (d, 4H); 9.20 (s, 2H).

[0089] Example 3

[0090] Preparation of imidazolyl dimeric acceptor, comprising the following steps:

[0091] (1) Synthesis of DBM-C8, whose synthetic route is as follows:

[0092]

[0093] BM (600 mg) and 1,8-dibromobutane (65 mg) were added to a dried round-bottom flask equipped with a magnetic stirring bar. After vacuum and refilling with argon 3 times, DMF (N,N-dimethylformamide) 30 mL and sodium tert-butoxide 300 mg were added to the round-bottom flask in turn. The above reaction mixture was stirred at 80 °C for 12 hours, after cooling to room temperature, poured into 150 mL of water, and extracted with ethyl acetate. The organic layer was washed with brine, dried with anhydrous magnesium sulfate, filtered, and the filtrate was rotary evaporated to obtain a sticky solid DBM-C8. The solid is a crude product, which is directly used for the next step reaction after being separated by a chromatographic column.

[0094] (2) Synthesis of DBMCHO-C8, whose synthetic route is as follows:

[0095]

[0096] The above crude product DBM-C8 was added to a dried round bottom flask equipped with a magnetic stir bar. After being evacuated and refilled with argon three times, 1,2-dichloroethane (20 mL), DMF (5 mL), and phosphorus oxychloride (1 mL) were added to the round bottom flask in this order. The reaction mixture was stirred at 80 °C for 10 hours, cooled to room temperature, poured into 150 mL of water, and extracted with dichloromethane. The organic layer was washed with brine, dried over anhydrous magnesium sulfate, filtered, and the filtrate was evaporated to give a yellow solid. The solid was further purified by silica gel column chromatography (petroleum ether: dichloromethane = 1:1 to 2:1) to give DBMCHO-C6 as a yellow solid (110.0 mg, 18% yield over two steps).

[0097] 1 H NMR (400 MHz, CDC13) δ: 0.49-0.67 (m, 36H); 0.79-0.98 (m, 60H); 1.20-1.38 (m, 62H); 1.40-1.51 (m, 12H); 1.82-1.99 (m, 18H); 2.74 (s, 6H); 3.09-3.20 (m, 8H); 4.52-4.60 (m, 12H); 10.10-10.11 (d, 4H).

[0098] (3) Synthesis of H2-C8, whose synthetic route is as follows:

[0099]

[0100] The resulting DBMCHO-C8 (110 mg) and IC-C1 (200 mg) were added to a dried round bottom flask equipped with a magnetic stir bar. After being evacuated and refilled with argon three times, chloroform (30 mL) and pyridine (0.6 mL) were added to the round bottom flask in this order. The reaction mixture was stirred at 60 °C for 12 hours, cooled to room temperature, concentrated to about 10 mL, and methanol (100 mL) was added. The resulting solid was further purified by flash silica gel column chromatography (petroleum ether: dichloromethane = 1:1 to 2:1) to give H2-C8 as a black solid (120 mg, 72.0% yield).

[0101] 1 H NMR (400 MHz, CDC13) δ: 0.63-0.73 (m, 32H); 0.80-0.89 (m, 26H); 0.93-1.00 (m, 28H); 1.11-1.31 (m, 70H); 1.35 (m, 4H); 1.47-1.67 (m, 20H);

[0102] 1.86-1.89 (m, 4H); 2.00-2.04 (m, 8H); 2.80 (s, 6H); 3.21-3.25 (m, 4H); 4.59 (s, 4H); 4.72-4.74 (d, 4H); 4.82-4.84 (d, 4H); 7.69 (s, 2H); 7.95 (s, 2H); 8.73 (s, 2H); 8.78 (s, 2H); 8.91 (s, 2H); 9.17 (s, 2H).

[0103] Example 4

[0104] Preparation of imidazolyl dimeric acceptor, comprising the following steps:

[0105] (1) Synthesis of DBM-C6O2, whose synthetic route is as follows:

[0106]

[0107] BM (600 mg) and bromo-triglycol-bromo (60 mg) were added to a dried round bottom flask equipped with a magnetic stir bar. After vacuum and refilling with argon 3 times, DMF (N,N-dimethylformamide) 30 mL and sodium tert-butoxide 300 mg were added to the round bottom flask in turn. The above reaction mixture was stirred at 80 °C for 12 hours, after cooling to room temperature, poured into 150 mL of water, and extracted with ethyl acetate. The organic layer was washed with brine, dried with anhydrous magnesium sulfate, filtered, and the filtrate was rotary evaporated to obtain a sticky solid DBM-C8. The solid was a crude product, which was directly used for the next step reaction after being separated by a chromatographic column.

[0108] (2) Synthesis of DBMCHO-C6O2, whose synthetic route is as follows:

[0109]

[0110] The above crude product DBM-C6O2 was added to a dried round bottom flask equipped with a magnetic stir bar. After vacuum and refilling with argon 3 times, 1,2-dichloroethane (20 mL), DMF (5 mL) and phosphorus oxychloride (1 mL) were added to the round bottom flask in turn. The above reaction mixture was stirred at 80 °C for 10 hours, after cooling to room temperature, poured into 150 mL of water, and extracted with dichloromethane. The organic layer was washed with brine, dried with anhydrous magnesium sulfate, filtered, and the filtrate was rotary evaporated to obtain a yellow solid. The solid was further purified by silica gel column chromatography (petroleum ether: dichloromethane = 1:1 to 2:1) to obtain DBMCHO-C6O2 (120.0 mg, 18.1% yield for two steps) in the form of a yellow solid.

[0111] 1H NMR (400 MHz, CDC13) δ: 0.48-0.70 (m, 38H); 0.71-0.99 (m, 78H); 1.16-1.25 (m, 22H); 1.32-1.38 (m, 12H); 1.40-1.49 (m, 8H); 1.73-1.94 (m, 18H); 2.70-2.76 (m, 6H); 3.11-3.22 (m, 8H); 3.36 (m, 4H); 3.93-3.97 (m, 4H); 4.53-4.80 (m, 12H); 10.11 (s, 4H).

[0112] (3) Synthesis of H2-C6O2, whose synthetic route is as follows:

[0113]

[0114] The resulting DBMCHO-C6O2 (60 mg) and IC-Cl (100 mg) were added to a dried round-bottom flask equipped with a magnetic stir bar. After vacuuming and refilling with argon 3 times, chloroform (30 mL) and pyridine (0.6 mL) were sequentially added to the round-bottom flask. The above reaction mixture was stirred at 60 °C for 12 hours, after cooling to room temperature, the reaction mixture was concentrated to about 10 mL and methanol (100 mL) was added. The resulting solid was further purified by flash silica gel column chromatography (petroleum ether: dichloromethane = 1:1 to 2:1) to obtain black solid H2-C6O2 (50 mg, yield 59.1%).

[0115] 1 H NMR (400 MHz, CDC13) δ: 0.61-0.69 (m, 32H); 0.82-1.10 (m, 68H); 1.19-1.23 (d, 54H); 1.43-1.56 (m, 12H); 1.72 (m, 4H); 1.82-1.84 (m, 4H); 1.99 (s, 4H); 2.80-2.93 (m, 8H); 3.20 (s, 4H), 3.49 (s, 4H); 4.04 (s, 4H); 4.70-4.80 (m, 12H); 7.84 (s, 2H); 7.95 (s, 2H); 8.76-8.78 (d, 4H); 9.02 (s, 2H); 9.14 (s, 2H).

[0116] Comparative Example 1

[0117] Preparation of the dimeric acceptor, comprising the following steps:

[0118] (1) Synthesis of BMCHO-CH3, whose synthetic route is as follows:

[0119]

[0120] BM-CH3(200mg) was added to a dried round-bottom flask equipped with a magnetic stir bar. After vacuum and backfilling with argon three times, 1,2-dichloroethane (20 mL), DMF (5 mL), and phosphorus oxychloride (1 mL) were sequentially added to the round-bottom flask. The reaction mixture was stirred at 80 °C for 10 h, cooled to room temperature, poured into 150 mL of water, and extracted with dichloromethane. The organic layer was washed with brine, dried over anhydrous magnesium sulfate, filtered, and the filtrate was rotary evaporated to give a yellow solid. The yellow solid was further purified by silica gel column chromatography (petroleum ether: dichloromethane = 1:1 to 2:1) to give BMCHO-CH3(145 mg, yield 69.0%) as a yellow solid.

[0121] 1 H NMR (400 MHz, CDC13) δ: 0.51-0.66 (m, 18H); 0.67-1.12 (m, 32H); 1.21-1.31 (m, 24H); 1.33-1.38 (m, 4H); 1.39-1.53 (m, 4H); 1.82-1.92 (m, 4H);

[0122] 3.21 (s, 3H); 4.36 (s, 3H); 4.61-4.73 (m, 4H); 10.13 (s, 2H).

[0123] (2) Synthesis of H0, whose synthetic route is as follows:

[0124]

[0125] BMCHO-CH3(70 mg) and IC-Cl (50 mg) prepared above were added to a dried round-bottom flask equipped with a magnetic stir bar. After vacuum and backfilling with argon three times, chloroform (30 mL) and pyridine (0.4 mL) were sequentially added to the round-bottom flask. The reaction mixture was stirred at 60 °C for 12 h, cooled to room temperature, concentrated to about 10 mL, and methanol (100 mL) was added. The solid was further purified by flash silica gel column chromatography (petroleum ether: dichloromethane = 1:1 to 2:1) to give H0 (70 mg, yield 81.8%) as a black solid.

[0126] 1 H NMR (400 MHz, CDC13) δ: 0.51-0.66 (m, 18H); 0.67-1.12 (m, 32H); 1.21-1.31 (m, 24H); 1.33-1.38 (m, 4H); 1.39-1.53 (m, 4H); 1.82-1.92 (m, 4H);

[0127] 1.93-1.89 (m, 2H); 2.74 (s, 3H); 3.12-3.24 (m, 4H); 4.36 (s, 3H); 4.61-4.73 (m, 4H); 7.93-7.95 (d, 2H); 8.77-8.79 (d, 2H); 9.14-9.15 (d, 2H).

[0128] Comparative Example 2

[0129] Preparation of the dimeric acceptor, comprising the following steps:

[0130] (1) Synthesis of BMCHO, whose synthetic route is as follows:

[0131]

[0132] BM (150 mg) was added to a dried round-bottom flask equipped with a magnetic stirring bar. After vacuum and refilling with argon 3 times, 1,2-dichloroethane (20 mL), DMF (5 mL) and phosphorus oxychloride (1 mL) were added to the round-bottom flask in turn. The above reaction mixture was stirred at 80 °C for 10 hours, after cooling to room temperature, poured into 150 mL of water, and extracted with dichloromethane. The organic layer was washed with brine, dried over anhydrous magnesium sulfate, filtered, and the filtrate was rotary evaporated to obtain a yellow solid. The yellow solid was further purified by silica gel column chromatography (petroleum ether: dichloromethane = 1:1 to 2:1) to obtain BMCHO (130.0 mg, yield 82.4%) as a yellow solid.

[0133] 1 H NMR (400 MHz, CDC13) δ: 0.47-0.67 (m, 18H); 0.79-0.87 (m, 16H); 0.90-1.02 (m, 12H); 1.23-1.32 (m, 32H); 1.35-1.43 (m, 4H); 1.81-1.96 (m, 6H); 2.82 (s, 3H); 3.10-3.14 (m, 4H); 4.55-4.60 (m, 4H); 10.11 (s, 2H).

[0134] (2) Synthesis of H1, whose synthetic route is as follows:

[0135]

[0136] BMCHO (70 mg) and IC-CI (80 mg) were added to a dried round-bottom flask equipped with a magnetic stir bar. After vacuum and argon refilling for 3 times, chloroform (20 mL) and pyridine (0.5 mL) were added to the round-bottom flask in turn. The above reaction mixture was stirred at 60 °C for 12 h, after cooling to room temperature, the reaction mixture was concentrated to about 10 mL and methanol (100 mL) was added. Filtration, the solid was further purified by flash silica gel column chromatography (petroleum ether: dichloromethane = 1:1 to 2:1) to give H1 (70 mg, yield 70.0%) as a black solid.

[0137] 1 H NMR (400 MHz, CDC13) δ: 0.66 (s, 16H); 0.87-1.01 (m, 40H); 1.26 (s, 18H); 1.35 (s, 4H); 1.50 (m, 4H); 1.87 (s, 4H); 2.01 (s, 2H); 2.86 (s, 3H); 3.22 (s, 4H); 4.71 (s, 4H); 7.95 (s, 2H); 8.80 (s, 2H); 9.17 (s, 2H).

[0138] Performance detection experiment

[0139] UV test was performed on H2-C4 prepared in Example 1, H2-C8 prepared in Example 3 and H0 prepared in Comparative Example 1:

[0140] The absorption spectra of H0, H2-C4 and H2-C8 in chloroform solution and thin film state were tested using a UV-visible spectrophotometer, and the optical band gap was calculated using the empirical formula (E g opt = 1240 / λ onset film ), where λ onset film is the absorption edge of the absorption spectrum of the acceptor material in thin film, Figure 2 The absorption spectra of H0, H2-C4 and H2-C8 in chloroform solution and thin film state were tested using a UV-visible spectrophotometer, and the optical band gap was calculated using the empirical formula (E Figure 2 It can be seen that in dilute solution, from monomer small molecule to dimer acceptor, the absorption spectrum shows a significant red shift phenomenon, and the molar absorption coefficient is significantly enhanced, which indicates that the dimer acceptor has stronger intramolecular charge transfer than the monomer small molecule. Figure 3 The absorption spectra of H0, H2-C4 and H2-C8 in chloroform solution and thin film state were tested using a UV-visible spectrophotometer, and the optical band gap was calculated using the empirical formula (E

[0141] Electrochemical tests were performed on H2-C4 prepared in Example 1, H2-C8 prepared in Example 3, and H0 prepared in Comparative Example 1, including measurement of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of H0, H2-C4 and H2-C8, and calculation of the band gap (E g ec ) of H0, H2-C4 and H2-C8:

[0142] H0, H2-C4 and H2-C8 were dissolved in chloroform to form a solution with a concentration of 1 mg / mL, and were dropped on the working electrode (drop diameter of 2 mm). A 0.1 M Bu4NPF6 acetonitrile solution was used as the electrolyte, a platinum wire was used as the counter electrode, Ag / Ag + was used as the reference electrode, and ferrocene was used as the standard. Electrochemical cyclic voltammetry was used to measure the redox potential, and then the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO), and the band gap (E g ec ) were calculated.

[0143] E HOMO = -Eox+ [(-4.8) + 0.34] (eV), E LUMO = -E red + [(-4.8) + 0.34] (eV)

[0144] The electrochemical cyclic voltammetry curves of H0, H2-C4 and H2-C8 are shown in Figure 4 . The energy levels of the monomer small molecules and the dimeric acceptor are obviously different, and the dimeric acceptor has lower LUMO and HOMO energy levels, which is conducive to the separation of excitons at the acceptor interface, thereby increasing the current of the system. At the same time, the electrochemical band gap E g ec calculated from the electrochemical test is consistent with the optical band gap E g opt calculated from the ultraviolet absorption, and the specific data are listed in Table 1.

[0145] Table 1

[0146]

[0147]

[0148] H2-C4 prepared in Example 1, H2-C8 prepared in Example 3, and H0 prepared in Comparative Example 1 were used as acceptors in bulk heterojunction structures, and performance tests were performed after the preparation of photovoltaic devices:

[0149] The fabrication and measurement procedure of the organic photodetector devices (OPDs) is as follows: First, the indium tin oxide (ITO) coated glass substrate was thoroughly cleaned with detergent, deionized water, acetone and isopropanol, each solvent was subjected to 15 minutes of ultrasonication, followed by drying in an oven at 80 °C. Next, the ITO glass substrate was treated in a UV-ozone environment for 25 minutes, followed by spin-coating of PEDOT:PSS solution and a 10 minutes thermal treatment at 150 °C. The mixed solution of PBDB-TF and the acceptor material in the present example (ratio 1 : 1.2) for spin-coating was 11 mg / mL with chloroform as the solvent. The mixed solution was added with chloronaphthalene (CN) as an additive with a volume content of 0.5% 30 minutes before spin-coating. The mixed solution was stirred overnight at room temperature in the glovebox. The active layer was formed by spin-coating the mixed solution at 3000 rpm for 30 seconds to form a mixed film. After that, a PNDIT-F3N solution (0.5 mg / mL in methanol) was spin-coated as an interlayer, and a 100 nm silver (Ag) layer was evaporated through a 0.045 cm2shadow mask to precisely define the active area of the device. Finally, the structure of the integrated device was ITO / PEDOT:PSS / PBDB-TF:acceptor

[0150] / PNDIT-F3N / Ag. A solar simulator (Enlitech. Inc) equipped with an AM 1.5G filter was used as the light source to generate a light intensity of 100 mW / cm 2 to irradiate the photodetector device. The light intensity was calibrated by a 2 cm x 2 cm calibrated silicon solar cell and a KG-5 visible light filter. To precisely define the photoactive area, a shadow mask was placed on the device. The external quantum efficiency curves of the H0, H2-C4 and H2-C8 bulk heterojunction photodetector devices were measured by a solar cell-photodetector response measurement system, and the dark current was measured by a Keithley 4200 source measurement unit, and the specific detectivity (Dsh*) at different voltages was calculated. The results are shown in Table 2, Figure 5 Figure 6 and Figure 7 are the external quantum efficiency curves, dark current curves and specific detectivity curves of the H0, H2-C4 and H2-C8 bulk heterojunction photodetector devices, respectively. The results show that the photodetector device based on the dimeric acceptor has a higher external quantum efficiency value than the photodetector device based on the monomeric small molecule, which indicates that the dimeric acceptor has a better packing, resulting in better charge transport. In addition, the dark current of the photodetector device based on the dimeric acceptor is also significantly lower than that of the photodetector device based on the monomeric small molecule, which leads to a significantly higher specific detectivity value in the photodetector device based on the dimeric acceptor, which indicates that the imidazole-based dimeric acceptor is a good photodetector material.

[0151] Table 2​

[0152]

[0153] H1 prepared in Comparative Example 2, H2-C6 prepared in Example 2 and H2-C6O2 prepared in Example 4 were prepared into nanoparticles, and then the related performance tests such as photodynamic therapy were carried out.

[0154] The preparation and measurement method of the nanoparticles is as follows: 0.5 mg of the sample and 5 mg of the amphiphilic block polymer DSPE-PEG5000 are dissolved in 2 mL of tetrahydrofuran solvent, and ultrasonic treatment is performed for 3-5 min until complete dissolution. Then 18 mL of deionized water is poured into the above-mentioned tetrahydrofuran mixed solution under ultrasonic condition, and ultrasonic treatment is continued for 10 min, followed by stirring at 40°C for 24 h to remove tetrahydrofuran. The nanoparticle solution (NPs) is filtered using a 220 nm filter membrane to remove impurities with large particle size. The high-concentration nanoparticle solution is enriched by centrifugation using a 50KD ultrafiltration centrifuge tube to remove free amphiphilic block polymer, and finally the high-concentration solution is diluted to 20 mL to obtain a nanoparticle mother liquor (25 μg·mL -1 ), which is stored in a 4°C refrigerator. In the fluorescence performance test experiment, 2.5 mL of the nanoparticle solution (25 μg·mL -1 ) is taken and placed in a four-side light-transmitting quartz dish, and spectral information is collected by means of a fluorescence spectrometer. As shown in Figure 8 , it can be seen that the fluorescence intensity of the dimeric acceptor is obviously enhanced compared with the monomer. DPBF probe is selected to measure the total active oxygen production of the nanoparticles under 808 nm laser irradiation of 0.3 W cm -2 . With the gradual increase of the active oxygen production under laser irradiation, DPBF will be degraded, thereby showing a decrease in the absorption value of the absorption spectrum. First, the DPBF solid is weighed and prepared into a 1 mg mL -1 solution with DMSO, and 10 μL of the DPBF solution is mixed with 90 μL of the three kinds of nanoparticle solutions in a 96-well plate. In addition, ICG is selected as a reference substance. Then at different laser irradiation time points, the absorption spectrum of each mixed solution at 350 nm to 500 nm is tested by using an enzyme marker instrument, and the highest point absorption value is normalized to obtain the degradation curve of DPBF. As shown in Figure 9 , the degradation rate of DPBF based on the dimeric nanoparticle is faster than that of the monomeric nanoparticle under the excitation of light, indicating that the dimer can produce more active oxygen molecules and has a better photodynamic effect. Therefore, the H2-C6 dimer nanoparticle with the best performance is selected to perform photodynamic therapy test on a mouse tumor model. Mice with about 90 mm 3 subcutaneous tumors are divided into 4 groups, the Control group is not treated, and the Laser group is only subjected to 808 nm laser irradiation (0.3 W cm-2 (15 min), the H2-C6 NPs group was injected with only 100 μg of H2-C6 dimer nanoparticles, while the H2-C6 NPs+ group was irradiated with an 808 nm laser (0.3 W cm⁻¹) at the optimal enrichment time point after nanoparticle injection. -2 (15 min). The optimal enrichment time point was obtained by near-infrared II fluorescence imaging of mice, such as... Figure 10 As shown, the fluorescence intensity of the tumor peaked at 36 hours. Two days after the mice underwent photodynamic therapy with laser irradiation at 36 hours, tumor size data were collected and growth curves were plotted to compare the treatment effects. Figure 11 As shown, compared with the other three groups that did not have photodynamic therapy, the tumor growth of mice in the H2-C6 NPs+ group was significantly inhibited, indicating that imidazole dimer receptor is a promising photodynamic therapy material.

[0155] It should be understood that the application of the present invention is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. An imidazolium dimer receptor, characterized in that, The general structural formula of the imidazole-based dimer receptor is: ; Where R1 is or R2 is , , or X1 and X2 are independently selected from H, F, Cl, Br, I, CH3 or OCH3, Y is selected from one of the C1-C10 alkane chains, and n is 0, 1, 2, 3, 4, 5 or 6.

2. The imidazole dimer receptor according to claim 1, characterized in that, The imidazole-based dimer receptor has one of the following structural formulas: , .

3. A method for preparing the imidazole dimer receptor according to claim 1, characterized in that, The preparation method includes the following steps: Will The first reactant and the first reaction solvent are mixed and stirred at a first temperature for a first time to obtain the structure with the following formula: The first product of the reaction; The first reaction product was mixed with the second reactant, the third reactant, and the second reaction solvent, and stirred at a second temperature for a second time to obtain the structure with the following formula: The second reaction product; The second reaction product and The fourth reactant and the third reaction solvent are mixed and stirred at a third temperature for a third time to obtain the imidazole dimer receptor. Wherein, the first reactant is sodium tert-butoxide, potassium tert-butoxide, sodium hydride, or potassium carbonate; the second reactant is N,N-dimethylformamide; the third reactant is phosphorus oxychloride or phosphorus oxybromide; and the fourth reactant is pyridine, piperidine, or sodium tert-butoxide. The first reaction solvent is N,N-dimethylformamide, dimethyl sulfoxide, or N-methylpyrrolidone; the second reaction solvent is 1,2-dichloroethane, dichloromethane, or chloroform; and the third reaction solvent is chloroform, dichloromethane, 1,2-dichloroethane, or tetrahydrofuran.

4. The method for preparing the imidazole dimer receptor according to claim 3, characterized in that, The The molar ratio of the reactant to the first reactant is 2:1:(2-10); The first temperature is 80-100℃, and the first time is 12-24 h.

5. The method for preparing the imidazole dimer receptor according to claim 3, characterized in that, The molar ratio of the first reaction product to the second and third reactants is 1:(2-10):(2-10); The second temperature is 80-100℃, and the second time is 10-24 h.

6. The method for preparing the imidazole dimer receptor according to claim 3, characterized in that, The second reaction product and The molar ratio of the fourth reactant is 1:4:(10-100); The third temperature is 60-80℃, and the third time is 12-24 h.

7. A photodetector, characterized in that, The photodetector includes the imidazole dimer receptor as described in claim 1.

8. The photodetector according to claim 7, characterized in that, The photodetector includes a substrate and an imidazole dimer acceptor film deposited on the substrate. The imidazole dimer acceptor film is prepared by mixing the imidazole dimer acceptor according to claim 1 with a polymer donor and then depositing the mixture on the substrate.

9. A biophototherapy nanoparticle, characterized in that, The biophototherapy nanoparticles include the imidazole dimer receptor as described in claim 1.

10. The biophototherapy nanoparticles according to claim 9, characterized in that, The The biophototherapy nanoparticles are obtained by encapsulating the imidazole dimer receptor described in claim 1 with hydrophilic polyethylene glycol.

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