Electrochemical luminescent material as well as preparation method and application thereof

Abstract

The invention provides an electrochemical luminescence material and a preparation method and application thereof, and belongs to the technical field of electrochemical luminescence. The electrochemical luminescent material comprises a plurality of unit structures I, and the chemical structural formula of each unit structure I is # imgabs0 #. According to the present invention, the synthesis cost can be reduced, and the application range is wide.

Description

Technical Field

[0001] This disclosure belongs to the technical field of electrochemiluminescence, and particularly relates to an electrochemiluminescent material, a preparation method thereof, and an application thereof. Background Art

[0002] Electrochemiluminescence (ECL) materials are a widely used type of luminescent material. The luminescence principle of ECL is to rely on continuous transitions to directionally conduct different charges, thereby achieving exciton quenching luminescence. There are many types of ECL materials, and transition metal complexes mainly based on Ru and Ir are the most common types (for example, the commercially available Ru(bpy)3 is a polypyridine transition metal complex). Among them, ECL in the near-infrared region can be used as an imaging auxiliary material in the biomedical field and has excellent application prospects.

[0003] However, although ECL in the near-infrared region has good performance, it is expensive, and there are many solvents harmful to the environment in the synthesis process. The metal part also limits the application of such compounds in fields with high requirements for biocompatibility and toxicity, such as biological detection. Summary of the Invention

[0004] Embodiments of this disclosure provide an electrochemiluminescent material, a preparation method thereof, and an application thereof, which can reduce costs and have a wide range of applications. The technical solutions are as follows:

[0005] In a first aspect, embodiments of this disclosure provide an electrochemiluminescent material, which includes a plurality of unit structures I, and the chemical structural formula of the unit structure I is:

[0006]

[0007] In another implementation manner of this disclosure, at least some of the plurality of unit structures form at least one ring structure, and the number of unit structures I included in each ring structure is greater than 2.

[0008] In another implementation manner of this disclosure, the number of unit structures I included in the ring structure is 3 or 4.

[0009] In a second aspect, a method for preparing the electrochemiluminescent material described above is also provided, the method comprising: subjecting 4-bromo-1,8-naphthalene dicarboxylic anhydride, 4-tert-butylaniline and ethanol to a reflux reaction, and purifying the product of the reflux reaction to obtain 4-bromo-N-(4-tert-butylphenyl)-1,8-naphthalene imide; mixing the 4-bromo-N-(4-tert-butylphenyl)-1,8-naphthalene imide with 9,10-dihydro-9,9-dimethylacridine, palladium salt, sodium tert-butoxide, tri-tert-butylphosphine tetrafluoroborate and toluene, and reacting the mixture, and purifying the product to obtain the unit structure I.

[0010] In another embodiment of the present disclosure, the product of the reflux reaction is purified, comprising: cooling the reflux product to room temperature, then removing the solvent under vacuum conditions to obtain a crude product, and recrystallizing the crude product with ethyl acetate to obtain a pure product.

[0011] In another implementation of the present disclosure, the method further includes: when obtaining the unit structure I, first NAI-Br, DMAC, palladium salt, sodium tert-butoxide, tri-tert-butylphosphine tetrafluoroborate and toluene are mixed, and refluxed in an argon atmosphere for not less than 24 hours, and then the reaction mixture after reflux is cooled to room temperature, and the reaction mixture is extracted with brine and chloroform, and the reaction mixture after extraction is dried with a desiccant; the solvent is removed from the dried reaction mixture in vacuum, and the crude product is purified by silica gel column chromatography to obtain the unit structure I.

[0012] In yet another implementation of the present disclosure, when the unit structure is obtained, the crude product is purified by silica gel column chromatography, using DCM / petroleum as the eluent, and the volume ratio of DCM / petroleum is 1:1-1:5.

[0013] In another implementation of the present disclosure, the method further comprises: reacting the unit structure I under the catalysis of paraformaldehyde, anhydrous dichloromethane and iron salt, and purifying the product to obtain the electrochemiluminescent material.

[0014] In yet another implementation of the present disclosure, the iron salt is FeCl3·6H2O.

[0015] In yet another implementation of the present disclosure, the palladium salt is any one of palladium chloride, palladium acetate, and palladium nitrate.

[0016] In another implementation of the present disclosure, the purifying of the product comprises: after reacting the unit structure I under the catalysis of paraformaldehyde, anhydrous dichloromethane and iron salt, quenching the reaction with water, collecting the organic phase, and filtering the organic phase after drying, concentrating the filtered product under reduced pressure to obtain a crude product, and then purifying the crude product by silica gel column chromatography to obtain electrochemiluminescent materials X and Y.

[0017] In yet another implementation of the present disclosure, when obtaining the electrochemiluminescent materials X and Y, the crude product is purified by silica gel column chromatography, using DCM / petroleum as the eluent, and the volume ratio of DCM / petroleum is 1:1 - 1:5.

[0018] In a third aspect, an application of an electrochemiluminescent material is further provided. The electrochemiluminescent material, together with a co-reactant, a two-electrode, and a supporting electrolyte, forms a near-infrared luminescence system and is applied in an infrared luminescence device; the two-electrode is located in a mixed solution of the electrochemiluminescent material, the co-reactant, and the supporting electrolyte, wherein the electrochemiluminescent material is the electrochemiluminescent material described above.

[0019] In yet another implementation of the present disclosure, the co-reactant includes an oxidation reaction co-reactant and / or a reduction reaction co-reactant

[0020] In yet another implementation of the present disclosure, the co-reactant is an oxidation reaction co-reactant, and the dosage of the oxidation reaction co-reactant is 1 - 5 molar equivalents of the electrochemiluminescent material.

[0021] In yet another implementation of the present disclosure, the oxidation reaction co-reactant is persulfate or benzoyl peroxide

[0022] In yet another implementation of the present disclosure, the co-reactant is a reduction reaction co-reactant, and the reduction reaction co-reactant is 1 - 20 molar equivalents of the electrochemiluminescent material.

[0023] In yet another implementation of the present disclosure, the reduction reaction co-reactant is tri-n-propylamine or dibenzoyl peroxide.

[0024] In yet another implementation of the present disclosure, the supporting electrolyte is an acetonitrile solution of tetrabutylammonium perchlorate with a concentration lower than 0.5 mol / L.

[0025] The beneficial effects brought by the technical solutions provided in the embodiments of the present disclosure are:

[0026] Since the electrochemiluminescent material provided in the embodiments of the present disclosure includes multiple unit structures, and each unit structure does not contain transition metals or heavy metals, the electrochemiluminescent material provided in the embodiments of the present disclosure can construct a near-infrared electrochemiluminescent material without transition metals and heavy metals, greatly reducing the synthesis cost, while expanding the application range of the material, enabling the material to be widely used in fields such as biomedical imaging.

[0027] Moreover, since the electrochemiluminescent material includes multiple unit structures, the synthesis method of the electrochemiluminescent material is relatively simple. It only needs to obtain the unit structure and then polymerize the unit structure. At the same time, the number of polymerized unit structures of the electrochemiluminescent material can be controlled, which can further expand the application range. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present disclosure. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0029] Figure 1 is a flowchart of a preparation method of an electrochemiluminescent material provided by an embodiment of the present disclosure;

[0030] Figure 2 is the 1H NMR spectrum of NAI-Br;

[0031] Figure 3 is the 1H NMR spectrum of NAI-DMAC;

[0032] Figure 4 is the electrochemiluminescent stacking diagram of NAI-DMAC;

[0033] Figure 5 is the CV and ECL voltage curve diagram of NAI-DMAC;

[0034] Figure 6 is the 1H NMR spectrum of NAI-DMAC[3];

[0035] Figure 7 is the mass spectrum of NAI-DMAC[3];

[0036] Figure 8 is the 1H NMR spectrum of NAI-DMAC[4];

[0037] Figure 9 is the mass spectrum of NAI-DMAC[4];

[0038] Figure 10 is the electrochemiluminescent stacking diagram of NAI-DMAC[3];

[0039] Figure 11 is the electrochemiluminescent stacking diagram of NAI-DMAC[4];

[0040] Figure 12 is the CV and ECL voltage curve diagram of NAI-DMAC[3];

[0041] Figure 13CV and ECL voltage curve of NAI-DMAC[4];

[0042] Figure 14 For the electrochemiluminescence (ECL) test spectrum of the electro-optic luminescent material with a concentration of 1×10 -5 M;

[0043] Figure 15 For the electrochemiluminescence (ECL) test spectrum of the electro-optic luminescent material with a concentration of 2×10 -3 M. Specific embodiments

[0044] To make the objectives, technical solutions, and advantages of the present disclosure clearer, the following will further describe the embodiments of the present disclosure in detail with reference to the accompanying drawings.

[0045] The embodiments of the present disclosure provide an electrochemiluminescent material, which includes a plurality of unit structures I, and the chemical structural formula of the unit structure I is:

[0046]

[0047] Since the electrochemiluminescent material provided by the embodiments of the present disclosure includes a plurality of unit structures, and each unit structure does not contain transition metals or heavy metals, etc., the electrochemiluminescent material provided by the embodiments of the present disclosure can construct an electrochemiluminescent material in the near-infrared region without transition metals and heavy metals, greatly reducing the synthesis cost. At the same time, the application range of the material is expanded, enabling the material to be applied in fields such as biomedical imaging that have strict requirements for biocompatibility and high requirements for near-infrared luminescence performance.

[0048] Moreover, since the electrochemiluminescent material includes a plurality of unit structures, the synthesis method of the electrochemiluminescent material is relatively simple. Only the unit structure needs to be obtained, and then the unit structure can be polymerized. At the same time, the number of polymerized unit structures of the electrochemiluminescent material can be controlled, further expanding the application range.

[0049] Optionally, at least some of the plurality of unit structures form at least one ring structure, and the number of unit structures I included in each ring structure is greater than 2. Here, at least some of the unit structures means that some of the unit structures form a ring structure. That is, the electrochemiluminescent material includes a ring structure formed by combining a plurality of unit structures I. And the so-called at least one ring structure means that it does not form a single ring structure, but can form ring structures of various structures. For example, every three unit structures in a part of the unit structures are combined to obtain a large ring structure X. The specific chemical structural formula is as follows:

[0050]

[0051] In another part of the unit structure, every four unit structures are combined to obtain a macrocyclic structure Y. The specific chemical structural formula is as follows:

[0052]

[0053] In still another part of the unit structure, macrocyclic structures obtained by combining every five, six or even more unit structures are not listed one by one here.

[0054] That is to say, the above-mentioned electrochemiluminescent material may not be a single compound, and may include at least one of a unit structure, a macrocyclic structure formed by combining three unit structures, a macrocyclic structure formed by combining four unit structures... macrocyclic structures formed by combining multiple unit structures, and so on.

[0055] Optionally, the number of unit structures I included in the cyclic structure is 3 or 4.

[0056] In this embodiment, the electrochemiluminescent material is a cyclic structure formed by 3 or 4 unit structures I.

[0057] On the other hand, the embodiments of the present disclosure also provide a method for preparing the electrochemiluminescent material described above. This method can prepare the electrochemiluminescent material NAI-DMAC[3]) and the electrochemiluminescent material NAI-DMAC[4] according to the following synthetic route:

[0058]

[0059] As Figure 1 shown, this method includes:

[0060] In S101: 4-bromo-1,8-naphthalic anhydride, 4-tert-butylaniline and ethanol are subjected to a reflux reaction, and the product of the reflux reaction is purified to obtain 4-bromo-N-(4-tert-butylphenyl)-1,8-naphthalimide.

[0061] Exemplarily, in S101, 4-bromo-1,8-naphthalic anhydride, 4-tert-butylaniline and ethanol are first mixed and refluxed for 3-5 days (for example, refluxed in argon).

[0062] After that, purification treatment is carried out. The purification treatment includes: after cooling the reflux product to room temperature, removing the solvent under vacuum conditions to obtain a crude product, and recrystallizing the crude product with ethyl acetate to obtain a pure product, which is 4-bromo-N-(4-tert-butylphenyl)-1,8-naphthalimide (denoted as NAI-Br).

[0063] In S102: NAI-Br is mixed with 9,10-dihydro-9,9-dimethylacridine (denoted as DMAC), palladium salt, sodium tert-butoxide, tri-tert-butylphosphine tetrafluoroborate and toluene for reaction, and the product is purified to obtain unit structure I.

[0064] Unit structure I is also 4-(tert-butyl)phenyl-6-(9,9-dimethylacridin-10(9H)-yl)-1H-benzo[de]isoquinoline-1,3(2H)-dione (abbreviated as NAI-DMAC).

[0065] Illustratively, in S102, NAI-Br, DMAC, palladium salt, sodium tert-butoxide, tri-tert-butylphosphine tetrafluoroborate, and toluene are mixed and refluxed in an argon atmosphere for not less than 24 hours.

[0066] After the reflux reaction, when the reaction mixture is purified, the reaction mixture is first cooled to room temperature, extracted with brine and chloroform, and dried over a desiccant (such as anhydrous Na2SO4).

[0067] After that, the solvent was removed in vacuo and the crude product was purified by silica gel column chromatography to obtain the pure product as a white solid, namely NAI-DMAC.

[0068] When the crude product is purified by silica gel column chromatography, DCM / petroleum can be used as the eluent, wherein the volume ratio of DCM / petroleum ranges from 1:1 to 1:5. In the disclosed embodiment, the volume ratio of DCM / petroleum is 1:2 when used as the eluent.

[0069] In S103: the unit structure I is reacted under the catalysis of paraformaldehyde, anhydrous dichloromethane and iron salt, and the product is purified to obtain an electrochemical luminescent material.

[0070] For example, in S103, the unit structure I is reacted under the catalysis of paraformaldehyde, anhydrous dichloromethane and iron salt, and the product is purified to obtain an electrochemiluminescent material including NAI-DMAC[3] and NAI-DMAC[4].

[0071] Mix iron salt (such as FeCl3·6H2O), NAI-DMAC and paraformaldehyde, and add anhydrous dichloromethane to obtain a mixed solution. Stir the mixed solution at room temperature for 2 hours. Then, quench the reaction with water. Collect the organic phase. Dry the organic phase with a desiccant (such as anhydrous Na2SO4), filter and concentrate under reduced pressure to obtain a crude product. The crude product is purified by silica gel column chromatography using DCM / petroleum (1:1-5v / v) as an eluent to obtain two yellow products NAI-DMAC[3] and NAI-DMAC[4]. In the disclosed embodiment, the volume ratio of DCM / petroleum as an eluent is 1:2.

[0072] It should be noted that: The electrochemiluminescent materials provided in the above embodiments are only illustrated by taking the methods for synthesizing NAI-DMAC[3] and NAI-DMAC[4] as examples. In practical applications, macrocyclic structures formed by combining different numbers of unit structures (such as the macrocyclic structure NAI-DMAC[5] formed by five unit structures, etc.) can be extracted according to needs, which will not be elaborated here.

[0073] The above method will be further illustrated by specific examples below.

[0074] (1) During synthesis, first, 5.0 g (i.e., 18.05 mmol) of 4-bromo-1,8-naphthalic anhydride, 3.23 g (i.e., 21.64 mmol) of 4-tert-butylaniline, and 150 mL of absolute ethanol were added to a 250 ml flask and refluxed for 3 days under an argon atmosphere. After cooling the refluxed product to room temperature, the solvent was removed by a rotary evaporator to obtain a crude product. Then, recrystallization with ethyl acetate was carried out to obtain a pure product (i.e., NAI-Br obtained in step S101), and the yield was 81.1%.

[0075] Combined with Figure 2 , the above-obtained compound was characterized by 1H NMR.

[0076] During detection, in order to obtain a higher-resolution spectrum, generally, the test sample needs to be dissolved in a solvent. In this embodiment, the selected solvent is deuterated chloroform (CDCl3). Since CDCl3 has extremely low interference in nuclear magnetic resonance signals. The deuterium atoms contained in CDCl3 have the same nuclear spin as hydrogen nuclei and hardly generate additional signals during detection, thus ensuring that the collected spectral data is pure and of high quality. Secondly, CDCl3 provides a highly stable and reproducible reference signal. In a complex nuclear magnetic resonance environment, the hydrogen and carbon signals in the solvent are often used for instrument calibration. Due to the stability and consistency of the reference signal of CDCl3, it can significantly improve the accuracy and reliability of the spectrum. In summary, due to its low interference and high-stability reference signal, CDCl3 can greatly improve the resolution of the spectrum, etc. as a solvent in 1H NMR detection.

[0077] During detection, the frequency of the 1H NMR is 400 MHz. That is, at a frequency of 400 megahertz, the signals generated by hydrogen atoms in nuclear magnetic resonance. At this frequency, the signals of hydrogen atoms are relatively strong and the interference is relatively small.

[0078] The characterization results of NAI-Br obtained in the above steps under 1H NMR (400 MHz, CDCl3) are shown in Figure 2 the 1H NMR spectrum.

[0079] SeeFigure 2 , Figure 2 The abscissa δ (i.e., δ in the specific information of the characteristic peak hereinafter) represents the chemical shift (used to reflect the chemical environment of hydrogen atoms in a compound, with the unit of ppm). The ordinate represents the peak intensity. Among them, the s peak (i.e., s in the specific information of the characteristic peak hereinafter) represents a singlet, referring to the signal emitted by a single hydrogen atom or the vibration state of a single hydrogen nucleus, with a unique signal intensity and only one precession frequency. The d peak (i.e., d in the specific information of the characteristic peak hereinafter) represents a doublet, which is composed of the signals emitted by two hydrogen atoms. When there are other hydrogen protons nearby, the nuclear spin has two orientations. One orientation increases the magnetic field magnitude received by the observed nucleus, and the other orientation decreases the magnetic field magnitude received by the observed nucleus. Based on the proportional relationship between the precession frequency and the net magnetic field, the signal of the observed nucleus changes from a singlet to a doublet, that is, the s→d peak. The t peak (i.e., t in the specific information of the characteristic peak hereinafter) represents a triplet, usually emitted by four hydrogen atoms (with coupling effects), showing three peaks with different signal intensities.

[0080] Combined with Figure 2 , the corresponding characteristic peaks from left to right are: A, δ 8.70 (d, J = 7.2 Hz, 1H), B, 8.63 (d, J = 8.5 Hz, 1H), C, 8.46 (d, J = 7.8 Hz, 1H), D, 8.08 (d, J = 7.9 Hz, 1H), E, 7.89 (t, J = 7.9 Hz, 1H), F, 7.56 (d, J = 8.0 Hz, 2H), G, 7.23 (d, J = 7.9 Hz, 2H), H, 1.38 (s, 9H). According to the characteristic peaks in the above hydrogen spectrum, it can be judged that the pure product synthesized according to the above steps is NAI-Br.

[0081] (2) Place 1.02 g (i.e., 2.50 mmol) of NAI-Br, 575 mg (i.e., 2.75 mmol) of DMAC (9,10-dihydro-9,9-dimethylacridine), 11 mg (i.e., 0.05 mmol) of Pd(OAc)2, 288 mg (i.e., 3.00 mmol) of tBuONa (sodium tert-butoxide), 44 mg (i.e., 0.15 mmol) of (tBu)3PHBF4 (tri-tert-butylphosphonium tetrafluoroborate), and 20 mL of toluene into a 100 ml round-bottom flask respectively.

[0082] Then, under argon protection, the reaction was refluxed for 24 hours. After the reaction was completed, it was cooled to room temperature, and the reaction mixture was extracted with saturated brine and chloroform, and the organic phase was collected. The organic phase was dried with anhydrous Na2SO4. Then the solvent was removed by a rotary evaporator to obtain a crude product. The crude product was purified by silica gel column chromatography using DCM (dichloromethane) / petroleum (1:2 v / v) as the eluent to obtain a pure product as a white solid, which was NAI-DMAC (i.e., unit structure I). Yield: 90%.

[0083] Similarly, the NAI-DMAC obtained in the above steps was characterized by 1H NMR (400 MHz, CDCl3) and HRMS (High-Resolution Mass Spectrometry, abbreviated as HRMS) (ESI, m / z).

[0084] The characterization results of NAI-DMAC under 1H NMR (400 MHz, CDCl3) are shown in Figure 3 . Combining Figure 3 , the corresponding characteristic peaks from left to right are: δ 8.86 (d, J = 7.7 Hz, 3H), 8.70 (d, J = 7.0 Hz, 3H), 8.13 (d, J = 8.3 Hz, 3H), 7.85 (d, J = 7.3 Hz, 3H), 7.68 (t, J = 7.7 Hz, 3H), 7.60 (d, J = 7.6 Hz, 6H), 7.29 (d, J = 8.8 Hz, 12H), 6.80 (d, J = 8.3 Hz, 6H), 6.02 (d, J = 8.1 Hz, 6H), 3.86 (s, 6H), 1.66 (s, 18H), 1.40 (s, 27H).

[0085] The calculated result in mass spectrometry analysis is 559.2360 [M+Na]+. And the calculated result of the standard mass spectrometry analysis of compound I C 37 H 32 N2NaO is 559.2361 [M+Na]+. The above can be used to judge that the pure product synthesized according to the above steps is unit structure I based on 1H NMR and mass spectrometry analysis.

[0086] In addition, an electrochemiluminescence stacking spectrum test was carried out on NAI-DMAC. Test conditions: The ECL voltage curve of the NAI-DMAC BPO system (an acetonitrile solution of 0.5 mM NAI-DMAC and 2 mM BPO, with 0.1 M TBAP as the supporting electrolyte) obtained by scanning from 0.25 to -1.55 V at a scanning speed of 0.1 V / s, and a spectrum was taken every 1 second to obtain Figure 4 the electrochemiluminescence stacking map of NAI-DMAC inFigure 4 , it can be seen that all the spectra in the figure overlap at the position of the wavelength λmax = 780 nm, indicating that the wavelength of the spectrum emitted by NAI-DMAC is λmax = 780 nm, which belongs to near-infrared light. That is, NAI-DMAC can be used as a near-infrared luminescent material in the field of electrochemiluminescence. At the same time, the CV and ECL curves of 0.5 mM NAI-DMAC and 2 mM BPO in acetonitrile were recorded at a scanning rate of 0.1 V / s, as Figure 5 shown. Combining Figure 5 with the upper CV curve in Figure 5 , it is not difficult to see that as the scanning voltage changes, the CV curve shows valleys and peaks in the response current. That is to say, in the voltage range where the material undergoes an electrochemical reaction, the current will change, eventually forming "peaks" or "valleys", and the potentials corresponding to the "peaks" or "valleys" during the positive scan (the direction of the lower arrow in the figure, that is, the voltage gradually increases) and the negative scan (the direction of the upper arrow in the figure, that is, the voltage gradually decreases) are very close, indicating that the material can emit light during both oxidation and reduction reactions when undergoing an electrochemical reaction. At the same time, combining

[0087] (3) 4.5 mg (i.e., 0.034 mmol) of FeCl3·6H2O was added to 200 mg (i.e., 0.34 mmol) of unit structure I (i.e., the pure product NAI-DMAC in the previous step), and then 92 mg (i.e., 1.1 mmol) of paraformaldehyde and 20 ml of anhydrous dichloromethane were further added and mixed. The reaction was stirred at room temperature for 2 hours. After the reaction was completed, water was added to quench it. The organic phase was collected after extraction, dried with anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography using petroleum and dichloromethane as eluents (v / v, 5:1) to obtain two yellow products NAI-DMAC[3] (60 mg, 29%) and NAI-DMAC[4] (20 mg, 10%).

[0088] The above two yellow products were characterized by 1H NMR (400 MHz, CDCl3) and 13C NMR MS of nuclear magnetic resonance respectively. The characterization results are shown in Figures 6 - 9 .

[0089] Figure 6 1H NMR spectrum of NAI-DMAC[3], combined with Figure 6 , where the peaks corresponding from left to right in the 1H NMR spectrum are: A, δ8.86 (d, J = 7.7 Hz, 3H), B, 8.70 (d, J = 7.0 Hz, 3H), C, 8.13 (d, J = 8.3 Hz, 3H), D, 7.85 (d, J = 7.3 Hz, 3H), E, 7.68 (t, J = 7.7 Hz, 3H), F, 7.60 (d, J = 7.6 Hz, 6H), G, 7.29 (d, J = 8.8 Hz, 12H), H, 6.80 (d, J = 8.3 Hz, 6H), I, 6.02 (d, J = 8.1 Hz, 6H), J, 3.86 (s, 6H), 1.66 (s, 18H), K, 1.40 (s, 27H).

[0090] Combined with Figure 7 , where the calculation result of 13C NMR MS (13C, Nuclear Magnetic Resonance, Mass Spectrometry, C13 nuclear magnetic resonance and mass spectrometry) is: 1645.7676 [M+H]+. And the chemical formula of NAI-DMAC[3] is C 114 H 96 N6O6, and the mass-to-charge ratio m / z = 1645.7470 [M+H]+. It can be seen that the above-mentioned NAI-DMAC[3] synthesized according to the above steps can be judged based on the 1H NMR spectrum and mass spectrometry analysis.

[0091] Figure 8 1H NMR spectrum of NAI-DMAC[4], combined with Figure 8 , where the peaks corresponding from left to right in the 1H NMR spectrum are: A, δ8.85 (d, J = 7.6 Hz, 4H), B, 8.68 (d, J = 7.1 Hz, 4H), C, 8.09 (d, J = 8.2 Hz, 4H), D, 7.82 (d, J = 6.4 Hz, 4H), E, 7.66 (t, J = 7.7 Hz, 4H), F, 7.59 (d, J = 7.8 Hz, 8H), G, 7.27 (d, J = 11.2 Hz, 16H), H, 6.75 (d, J = 8.3 Hz, 8H), I, 5.90 (d, J = 8.3 Hz, 8H), J, 3.82 (s, 8H), K, 1.73 (d, J = 19.5 Hz, 24H), L, 1.40 (s, 36H).

[0092] Combined with Figure 9 , where the calculation result of 13C NMR MS is: mass-to-charge ratio m / z = 2194.2399 [M+H]+. And the chemical formula of NAI-DMAC[4] is C 152 H 128N8O8, with a mass-to-charge ratio of m / z = 2193.9933 [M+H]+. It can be seen that the above-mentioned NAI-DMAC synthesized according to the above steps can be judged based on the hydrogen spectrum and mass spectrometry analysis.

[0093] In addition, electrochemical luminescence stacking spectra tests were performed on NAI-DMAC[3] and NAI-DMAC[4]. Test conditions: The ECL voltage curves of NAI-DMAC[3] and NAI-DMAC[4] respectively and the BPO system (an acetonitrile solution of 0.5 mM NAI-DMAC and 2 mM BPO, with 0.1 M TBAP as the supporting electrolyte) obtained by scanning from 0.25 to -1.55 V at a scanning rate of 0.1 V / s. One spectrum was taken every 1 second, and the Figure 10 electrochemical luminescence stacking diagram of NAI-DMAC[3] in Figure 11 and the

[0094] Combined with Figure 10 and 11 , it can be seen that the inset shows the overlap of all spectra concentrated at a wavelength λmax = 800 nm, similar to Figure 4 . At the same time, the CV and ECL voltage curves of 0.5 mM NAI-DMAC[3] and 2 mM BPO in acetonitrile were recorded at a scanning rate of 0.1 V / s as shown in Figure 12 . Among them, Figure 12 is similar to Figure 5 , which will not be elaborated here. And the CV and ECL voltage curves of 0.5 mM NAI-DMAC[4] and 2 mM BPO in acetonitrile were recorded at a scanning rate of 0.1 V / s, as shown in Figure 13 . Among them, Figure 12 , Figure 13 are both similar to Figure 5 , which will not be elaborated here. The above test results can clearly show that the material has an electrochemical luminescence phenomenon in the near-infrared region. That is, the monomer structure has a near-infrared electrochemical luminescence effect under single or multiple ring-forming conditions.

[0095] The compound prepared according to the above method in the embodiments of the present disclosure can realize the construction of a near-infrared region electrochemical luminescence material without transition metals and heavy metals, greatly reducing the synthesis cost. At the same time, it expands the application range of the material, making it possible to be applied in fields such as biomedical imaging that have strict requirements for biocompatibility and high requirements for near-infrared region luminescence performance. Moreover, the above electrochemical luminescence material, as a macrocyclic material, has good luminescence efficiency in the near-infrared region. And the above method has a simple process, and at the same time, the hollow structure of the obtained macrocyclic material is controllable and adjustable, which is very friendly to the development and application of a series of materials.

[0096] On the other hand, an embodiment of the present disclosure also provides an application of an electrochemiluminescent material. The electrochemiluminescent material, together with a coreactant, a pair of electrodes, and a supporting electrolyte, forms a near-infrared luminescence system and is applied in an infrared light-emitting device. The pair of electrodes is located in a mixed solution of the electrochemiluminescent material, the coreactant, and the supporting electrolyte, where the electrochemiluminescent material is the electrochemiluminescent material mentioned above.

[0097] A macrocyclic compound is used as a near-infrared electrochemiluminescent material, and together with a coreactant, a pair of electrodes, and a supporting electrolyte, an electrochemiluminescent system is constructed to achieve luminescence performance in the near-infrared region. The addition of the coreactant can shorten the response time.

[0098] Optionally, the coreactant includes an oxidation reaction coreactant and / or a reduction reaction coreactant.

[0099] The coreactant, also known as the coreagent, is a substance that generates an intermediate with strong reducibility or strong oxidizability through an oxidation or reduction reaction in an electrochemiluminescence reaction. These intermediate substances can react with the luminescent group to generate excited-state molecules, thereby producing a luminescence phenomenon.

[0100] For example, when a certain voltage is applied to the electrode, the coreagent is oxidized to an oxidized state. Subsequently, the covalent bond of the coreagent is broken to form an active intermediate with strong reducing energy. These intermediates react with the luminescent group of the electrochemiluminescence system to generate excited-state molecules, and when these molecules return to the ground state, light is emitted. Generally speaking, the coreagent can improve the luminescence efficiency of the luminescent group of ECL and the sensitivity of the ECL biosensor.

[0101] Optionally, the coreactant is an oxidation reaction coreactant, and the dosage of the oxidation reaction coreactant is 1-5 molar equivalents of the electrochemiluminescent material.

[0102] When the coreactant is an oxidation reaction coreactant, when a certain voltage is applied to the electrode, the coreactant is oxidized to an oxidized state. Subsequently, the covalent bond of the coreactant is broken to form an active intermediate with strong reducing energy. These intermediates react with the luminescent group of the electrochemiluminescence system to generate excited-state molecules, and when these molecules return to the ground state, light is emitted. Moreover, setting the dosage of the oxidation reaction coreactant to 1-5 molar equivalents of the electrochemiluminescent material can ensure that the dosage of the oxidation reaction coreactant is not less than that of the electrochemiluminescent material, so that the electrochemiluminescent material can fully react and improve the luminescence efficiency of the electrochemiluminescent material.

[0103] For example, the oxidation reaction coreactant can be persulfate or peroxybenzoic acid.

[0104] Optionally, the co-reactant is a co-reactant for the reduction reaction, and the co-reactant for the reduction reaction is 1-20 molar equivalents of the electrochemiluminescent material.

[0105] When the co-reactant is a co-reactant for the reduction reaction, when a certain voltage is applied to the electrode, the co-reactant is reduced to the reduced state. Subsequently, the covalent bond of the co-reactant is broken to form active intermediates with strong reducing energy. These intermediates react with the luminescent groups of the electrochemiluminescent system to generate excited-state molecules, which emit light when they return to the ground state. Moreover, the amount of the co-reactant for the reduction reaction is set to 1-20 molar equivalents of the electrochemiluminescent material, so that the amount of the co-reactant for the reduction reaction is not less than that of the electrochemiluminescent material, enabling the electrochemiluminescent material to react fully and improving the luminescence efficiency of the electrochemiluminescent material. Moreover, generally, the reduction potential of the co-reactant for the reduction reaction is less than the oxidation potential of the co-reactant for the oxidation reaction, so the amount of the co-reactant for the reduction reaction is relatively more with respect to the electrochemiluminescent material.

[0106] The co-reactant for the reduction reaction is tri-n-propylamine or benzoyl peroxide (BPO).

[0107] The supporting electrolyte is an acetonitrile solution of tetrabutylammonium perchlorate (TBAP) with a concentration lower than 0.5 mol / L.

[0108] The supporting electrolyte is an electrolyte that can improve the conductivity of the solution in the chemical cell and does not participate in the electrochemical reaction itself.

[0109] Tetrabutylammonium perchlorate has a wide electrochemical window and is suitable for systems with a wide test range. Moreover, TBAP has the characteristic of stable chemical properties and is suitable for a variety of electrochemical experiments. The price of TBAP is relatively low and it is easy to prepare, making it suitable for large-scale use.

[0110] That is to say, the acetonitrile solution of TBAP is often used in electrochemical research, especially in systems that require a wide electrochemical window and high stability. Due to its stable chemical properties and low price, it is suitable for a variety of electrochemical experiments. Namely, the acetonitrile solution of tetrabutylammonium perchlorate has a wide application in electrochemical research as a supporting electrolyte.

[0111] The ultraviolet fluorescence test spectra of the above electrochemiluminescent materials are as Figure 14 and 15 shown. Among them Figure 14 are the ultraviolet absorption and fluorescence emission diagrams of NAI-DMAC with a concentration of 1×10 -5 M, NAI-DMAC[3] with a concentration of 1×10 -5 M, and NAI-DMAC[4] with a concentration of 1×10 -5 M. Figure 15 is for a concentration of 2×10 -3NAI-DMAC of M, 2×10 -3 NAI-DMAC[3] of M, and 2×10 -3 Ultraviolet absorption and fluorescence spectra of NAI-DMAC[4] of M. Combining Figure 14 and Figure 15 , the ultraviolet absorption peak is around 300 nm, indicating that the electrochemiluminescence material has groups that can absorb ultraviolet-visible light, that is, chromophores, which can absorb light of a certain wavelength (color) and thus show color. And according to Figure 14 and Figure 15 , it can be seen from the fluorescence spectra in

[0112] that the peak values of the fluorescence emission peaks of the above electrochemiluminescence materials are all between 600 nm and 700 nm, and the excitation wavelength and emission wavelength have a large difference, indicating strong anti-interference ability, showing that they are all ECL materials with good application potential.

[0113]

[0114] Among them, the ECL efficiency of the constructed near-infrared luminescence system above can be calculated according to the following calculation formula (1): x where Φ is the integral of light intensity over time, is the integral of current over time, and a and b are the upper and lower limits of time respectively. In formula (1), x corresponds to the above electrochemiluminescence materials, and st is a reference standard material, such as Ru(bpy)3 2+ . If calculated according to the efficiency of the most important ECL material Ru(bpy)3 2+ being 100%, the compound can achieve an efficiency conversion of more than 90%.

[0115] The above are only optional embodiments of the present disclosure, and are not intended to limit the present disclosure. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present disclosure shall be included within the protection scope of the present disclosure.

Claims

1. An electrochemiluminescent material, characterized in that, The electrochemiluminescent material comprises a plurality of unit structures I, and the chemical structural formula of the unit structure I is:

2. The electrochemiluminescent material according to claim 1, wherein At least some of the multiple unit structures form at least one ring structure, and the number of unit structures I included in each of the ring structures is greater than 2.

3. The electrochemiluminescent material according to claim 2, wherein The number of unit structures I included in the ring structure is 3 or 4.

4. A method for preparing the electrochemiluminescent material according to claim 1, characterized in that, The method comprises: 4-bromo-1,8-naphthalene dicarboxylic anhydride, 4-tert-butylaniline and ethanol are subjected to reflux reaction, and the product of the reflux reaction is purified to obtain 4-bromo-N-(4-tert-butylphenyl)-1,8-naphthalene imide; The 4-bromo-N-(4-tert-butylphenyl)-1,8-naphthalimide is mixed with 9,10-dihydro-9,9-dimethylacridine, palladium salt, sodium tert-butoxide, tri-tert-butylphosphine tetrafluoroborate and toluene for reaction, and the product is purified to obtain the unit structure I.

5. The method according to claim 4, wherein The method further comprises: reacting the unit structure I under the catalysis of paraformaldehyde, anhydrous dichloromethane and iron salt, and purifying the product to obtain the electrochemical luminescent material.

6. The method according to claim 4, characterized in that The palladium salt is any one of palladium chloride, palladium acetate and palladium nitrate.

7. Application of an electrochemiluminescent material, characterized in that, The electrochemical luminescent material, the co-reactant, the double electrode and the supporting electrolyte form a near-infrared luminescent system for use in infrared luminescent devices; The dual electrodes are located in a mixed solution of the electrochemiluminescent material, the co-reactant and the supporting electrolyte, wherein the electrochemiluminescent material is the electrochemiluminescent material according to claim 1.

8. The application according to claim 7, wherein The co-reactant is an oxidation reaction co-reactant, and the amount of the oxidation reaction co-reactant is 1-5 molar equivalents of the electrochemical luminescent material.

9. The application according to claim 7, wherein The co-reactant is a reduction reaction co-reactant, and the reduction reaction co-reactant is 1-20 molar equivalents of the electrochemiluminescent material.

10. The application according to claim 7, characterized in that, The supporting electrolyte is an acetonitrile solution of tetrabutylammonium perchlorate with a concentration lower than 0.5 mol / L.

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