A ruthenium-based azine complex electrochemiluminescence material and a preparation method thereof

Abstract

The application discloses a ruthenium-based azine compound electrochemiluminescence material and a preparation method thereof. In a basic unit structure of the luminescence material, a central metal element is a Ru ion, a coordination group is an azine group, and an auxiliary coordination group is a pyridine group. The preparation method comprises the following steps: preparing a CTFs aqueous solution from a crystalline covalent triazine framework material; adding a Ru ion solution under magnetic stirring, performing vacuum filtration, and then dispersing in deionized water; after reaction, centrifugation, deionized water washing, removal of supernatant, precipitation and vacuum drying, a powder is obtained; the powder is dispersed in deionized water again, a mercapto pyridine solution is added, and reaction, centrifugation, washing and vacuum drying are performed to obtain the ruthenium-based azine compound electrochemiluminescence material. The application has the advantages of simple preparation, low cost, strong signal stability, and ECL efficiency reaching the level of commercial Ru(bpy)3 2+ , and is expected to be used as a new type of ECL probe, develop an in-vitro detection kit, and be applied to the field of in-vitro medical detection.

Description

Technical Field

[0001] This invention relates to a ruthenium aziridine complex electrochemiluminescent material (ECL) and its preparation method, belonging to the field of biomedical detection technology. Background Technology

[0002] Electrochemiluminescence (ECL) is an analytical technique that combines electrochemistry and chemiluminescence. In this system, the luminescent material undergoes an electrochemical reaction at the electrode, and the reaction products form excited-state substances through chemical reactions. Upon returning to the ground state, these substances emit light. This technique boasts significant advantages such as zero background, no photobleaching, two-dimensional spatial distribution, and time-modulated characteristics, gradually becoming a cutting-edge in vitro detection platform with broad application prospects in trace biomarker detection. In particular, Roche's Cobas e601 and Cobas e601 fully automated immunoassay analyzers utilize ruthenium tripyridine (Ru(bpy)3) 2+ Ru(bpy)3 is a luminescent molecule that has been used to detect 105 disease biomarkers, capturing nearly half of the domestic in vitro diagnostic market share and being widely applied in major tertiary hospitals across the country. However, this technology... 2+ Due to the heavy atom effect, ECL technology is inefficient and the technology is monopolized by foreign companies, making it expensive and difficult to popularize in large quantities, which restricts the application of ECL technology in in vitro detection.

[0003] Currently, framework materials and metallic nanomaterials, due to their large specific surface area and active surface electronic properties, possess the potential to serve as Ru(bpy)3 2+ Potential for alternative materials. For example, Yuan Ruo's research group used bovine serum albumin (BSA) as a protecting group to adsorb copper ions and then reduce it in situ to obtain copper nanoclusters (Cu NCs). Then, hydrazine hydrate (HZ) was deposited on the electrode surface to enhance the electron transfer efficiency of CuNCs, resulting in a significant ECL response (Anal. Chem. 2016, 88, 23, 11527-11532, Method 1). In addition, Cola's research group synthesized bis(3-(trifluoromethyl)-1H-1,2,4-triazol-5-yl)pyridine (PEG) to coordinate Pt(II) ions, reducing the molecular orbital energy level difference through molecular aggregation effects and improving the ECL signal of the material (J. Am. Chem. Soc. 2017, 139, 14605-14610, Method 2). Although the above techniques produce novel ECL materials, they suffer from problems such as low ECL efficiency and difficulty in using universal co-reactants (as in Method 1); furthermore, they also have drawbacks such as high cost and complex organic synthesis steps (as in Method 2). Therefore, developing new materials that are low-cost, easy to synthesize, and have high ECL efficiency remains a critical issue that urgently needs to be addressed.

[0004] Crystalline covalent triazine frameworks (CTFs) possess advantages such as low density, high specific surface area, and ease of modification and functionalization, and have shown broad application prospects in gas storage and separation, heterogeneous catalysis, energy storage materials, and optoelectronic sensing. In particular, the azine groups in these materials act as strong hydrogen bond acceptors, and the lone pair electrons of nitrogen exhibit strong coordination effects, enabling them to combine and react with numerous transition metal ions, generating unique photo / electro-activity, and thus holding promise as novel ECL materials. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a method for preparing an electrochemiluminescent material with high ECL efficiency and readily available materials.

[0006] To address the aforementioned technical problems, this invention provides a ruthenium-based azirconium complex electrochemiluminescent material, the structural formula of which is: Where n is a natural number; in the basic unit structure of the luminescent material, the central metal element is Ru(III) ion, the coordinating group is azinyl, and the auxiliary coordinating group is pyridyl.

[0007] Preferably, the azinon-coordinating material is a crystalline covalent triazine framework material.

[0008] Preferably, the coordination ratio of Ru(III) ion, azino:pyridinyl is 1:2:(1-5), wherein the coordination ratio of pyridinyl can be achieved by changing the feeding ratio of its coordination material.

[0009] This invention also provides a method for preparing the above-mentioned ruthenium azirconium complex electrochemiluminescent material, comprising the following steps:

[0010] Step 1): The crystalline covalent triazine framework material is ultrasonically dispersed in deionized water to prepare an aqueous solution of CTFs; Ru(III) Ru ion solution is added under magnetic stirring, vacuum filtered, and then dispersed in deionized water. After reaction, the mixture is centrifuged, washed with deionized water, the supernatant is removed, the precipitate is precipitated and vacuum dried to obtain powder.

[0011] Step 2): The powder obtained in Step 1) is redispersed in deionized water, a mercaptopyridine solution is added, the mixture is reacted under stirring, centrifuged and washed, and then vacuum dried to obtain the ruthenium aziridine complex electrochemiluminescent material.

[0012] Preferably, in step 1), the Ru(III)-containing Ru ion solution is hexaammineruthenium trichloride.

[0013] Preferably, in step 1), the mass concentration ratio of the effective component in the Ru ion solution to the effective component in the CTFs aqueous solution is 1:(1-2).

[0014] Preferably, in step 2), the mass concentration ratio of the powder to the active ingredient in the mercaptopyridine solution is 1:(2-4).

[0015] For traditional Ru(bpy)3 2+ The ECL materials of this invention suffer from drawbacks such as low efficiency and high cost. To address these issues, this invention provides a ruthenium-based azirconium complex ECL material structure and preparation method. The complex material is obtained by reacting CTFs and mercaptopyridine with ruthenium ions via coordination bonds, and is suitable for in vitro biomarker detection using an ECL platform. The ECL material prepared by this method has advantages such as simple synthesis, low cost, and high ECL efficiency, and can be applied to the development of in vitro detection kits. Attached Figure Description

[0016] Figure 1 The images show the SEM and mapping spectra of the Ru-CTFs-Py material in Example 1; where (A) is the SEM image of the Ru-CTFs-Py material, and (B), (C), and (D) are the elemental distribution maps of C, N, and Ru, respectively.

[0017] Figure 2 The XPS spectra of the Ru-CTFs-Py material in Example 1 are shown below; where (A) is the full XPS spectrum of the Ru-CTFs-Py material and (B) is the high-resolution XPS spectrum of Ru 3p.

[0018] Figure 3 The image shows the UV-vis spectrum of the Ru-CTFs-Py material in Example 2; where a, b, and c refer to CTFs, Ru-CTFs-Py, and Ru, respectively.

[0019] Figure 4 The image shows the FL spectrum of the Ru-CTFs-Py material in Example 2; where a, b, c, and d refer to Ru-CTFs, Ru-CTFs-Py, Ru, and CTFs, respectively.

[0020] Figure 5 The image shows the ECL spectrum of the Ru-CTFs-Py material in Example 2; where a and b refer to Ru-CTFs-Py and CTFs, respectively.

[0021] Figure 6 ECL signal diagram of Ru-CTFs-Py material in Example 3; where a, b, c, and d refer to Ru-CTFs-Py, TPA, CTFs, and Ru-CTFs, respectively;

[0022] Figure 7 The CV curves are for the Ru-CTFs-Py material in Example 3; where a and b refer to Ru-CTFs-Py and blank TPA, respectively. Detailed Implementation

[0023] To make the present invention more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings.

[0024] Example 1

[0025] A method for preparing a ruthenium-azine complex electrochemiluminescence (ECL) material, comprising the following steps:

[0026] Step 1: Commercially available CTFs material (purchased from Suzhou Beike Nanotechnology Co., Ltd.) was ground and ultrasonically dispersed in 2 mL of deionized water to obtain a uniform suspension of 1 mg / mL. An equal volume of Ru(III) solution was slowly added under magnetic stirring. After vacuum filtration, the suspension was further dispersed in 4 mL of deionized water. After reacting with magnetic stirring for 12 h, the mixture was centrifuged at 12000 rpm, washed with deionized water, and the supernatant was removed to obtain a black precipitate. The precipitate was then vacuum dried to obtain a black powder.

[0027] Step 2: The black powder obtained in Step 1 was ultrasonically dispersed in 1 mL of deionized water to obtain a homogeneous mixture. 1 mL of mercaptopyridine solution was slowly added, and the mixture was magnetically stirred for 6 h. After centrifugation at 12000 rpm, the mixture was washed with deionized water, and the precipitate was vacuum dried to obtain Ru-CTFs-Py material.

[0028] like Figure 1 As shown in Figure (A), the morphology and structure of the synthesized ruthenium-based aziridine complex ECL material were characterized using scanning electron microscopy (SEM). The complex exhibits an irregular granular structure with a size in the micrometer range. The electron energy dispersive spectroscopy (EDS) spectrum shows that the material contains C, N, Ru, and S elements (…). Figure 1 In the complex (B), (C), and (D), the ratio of the three elements was 87.15:7.39:1:4.46, and the four elements were evenly distributed. Further X-ray electron spectroscopy (XPS) was used to study the elemental speciation and content in the complex, such as... Figure 2 As shown in (A), the XPS full spectrum of the complex shows distinct diffraction peaks at 284.8 eV, 398.55 eV, 455.84 eV, and 163.86 eV, corresponding to C, N, Ru, and S, respectively. Comparison with electronic energy dispersive spectroscopy data further confirms that the complex's ratio of Ru:azinyl:pyridine is 1:2:4. Furthermore, two distinct diffraction peaks at 484 eV and 462 eV can be decomposed in the 3p XPS image of Ru, attributing to the trivalent peaks of Ru. Figure 2 (B) shows the ionic valence state of the de-coordination compound, proving that it is consistent with the material's basic unit.

[0029] Example 2

[0030] The optical properties of the composite were studied using ultraviolet absorption (UV-vis) spectroscopy, fluorescence (FL) spectroscopy, and ECL spectroscopy. For example... Figure 3 As shown, the Ru-CTFs-Py material prepared in Example 1 showed a significant conjugate absorption peak at 461 nm (curve b), while the corresponding ruthenium ions themselves did not show significant absorption in the visible light region (curve c), and the CTFs themselves did not show any absorption (curve a), indicating the coordination effect between ruthenium metal ions and the framework material.

[0031] like Figure 4 As shown, in the FL spectrum, CTFs and ruthenium ion solutions did not exhibit any emission peaks (curves d and c). However, after coordination between CTFs and Ru ions, a significant emission peak appeared at 461 nm (curve a). Furthermore, after assisted binding with mercaptopyridine, the fluorescence emission peak of the complex red-shifted to 593 nm and its intensity significantly increased, confirming the enhancing effect of pyridine coordination on the photon radiation of the complex (curve b). In addition, as... Figure 5 As shown, no emission peaks were observed in the CTFs in the ECL spectrum (curve a), while the ruthenium aziridine complex showed enhanced emission peaks at 650 nm (curve b), demonstrating the synthesis of the Ru-CTFs-Py composite material and its excellent optical properties.

[0032] Example 3

[0033] Study on the ECL properties of ruthenium aziridine complexes.

[0034] ECL mechanism of ruthenium aziridine complex. First, the Ru-CTFs-Py material prepared in Example 1 was ultrasonically dispersed in deionized water for 30 min to obtain a suspension.

[0035] Next, the 5mm diameter glassy carbon electrode (GCE) was polished for 3 minutes on 0.3μM alumina chamois leather. Each time, the alumina adsorbed on the electrode surface was rinsed off with ultrapure water. Then, it was ultrasonicated with acetone, ethanol, and deionized water and dried with nitrogen gas for later use.

[0036] Next, 20 μL of Ru-CTFs-Py material solution was dropped onto the surface of the treated glassy carbon electrode and dried overnight in a desiccator to obtain the working electrode.

[0037] Finally, a PBS solution containing 10 mM tripropylamine (TPA) (pH = 8.0) was used as the detection solution, and the parameters of the ECL analysis system were set as follows: photomultiplier tube bias voltage: 600 V; amplification stage: 3; scan rate: 100 mV·s -1 Using Ag / AgCl as the reference electrode and a platinum electrode as the counter electrode, the scanning potential range was adjusted to -0.6 to 1.3 V. The ECL signal of the modified electrode was detected, and the ECL signal intensity was recorded.

[0038] like Figure 6As shown, the Ru-CTFs-Py / TPA system exhibits an ECL peak at 0.96 V with a peak intensity as high as 9550 a.u. (curve a). From the ECL luminescence intensity, no ECL signal was detected in the blank TPA sample (curve b), strongly indicating that Ru-CTFs-Py and TPA can undergo an ECL reaction. On the other hand, from the redox peaks in the CV curve, as mentioned earlier, the Ru-CTFs-Py material shows an oxidation peak at 0.96 V (curve b), and TPA shows an oxidation peak at 0.91 V (curve a), indicating that TPA also undergoes an oxidation reaction and loses electrons at this voltage. Since the oxidation voltage of Ru-CTFs-Py material (0.69 V) is lower than the 0.78 V corresponding to the oxidation reaction of TPA, the ECL equation of the composite is derived as follows:

[0039] TPrA-e - →TPrA ·+ →TPrA · +H + (1-1)

[0040] CTFs-Ru 3+ -Py+TPrA · →CTFs-Ru 2+ -Py*+P1 (1-2)

[0041] CTFs-Ru 2+ -Py*→CTFs-Ru 2+ -Py+hv(650 nm) (1-3)

[0042] like Figure 7 As shown, CTFs themselves do not possess any ECL properties, but after binding with Ru ions, they exhibit significant ECL radiation at 1.21 V. Similarly, the ECL signal intensity also increases after coordination with mercaptopyridine. Based on theoretical calculations, the ECL efficiency equation for the Ru-CTFs-Py material is as follows:

[0043]

[0044] The ECL efficiency of the complex in the TPA assay solution was 1.0185, compared to that of the traditional Ru(bpy)3. 2+ The system (defined as 1) shows that the Ru-CTFs-Py material has 101.85% of its ECL efficiency, making it an effective alternative material.

Claims

1. A ruthenium-based azirconium complex electrochemiluminescent material, characterized in that, The structural formula of the luminescent material is: Where n is a natural number; in the basic unit structure of the luminescent material, the central metal element is Ru(III) ion, the coordinating group is azinyl, and the auxiliary coordinating group is pyridyl.

2. The ruthenium-based azirconium complex electrochemiluminescent material as described in claim 1, characterized in that, The coordinating material of the azine group is a crystalline covalent triazine framework material.

3. The ruthenium-based azirconium complex electrochemiluminescent material as described in claim 1, characterized in that, The coordination ratio of Ru(Ⅲ) ion, azinyl:pyridyl is 1:2:(1-5).

4. The method for preparing the ruthenium azirconium complex electrochemiluminescent material according to any one of claims 1-3, characterized in that, Includes the following steps: Step 1): The crystalline covalent triazine framework material is ultrasonically dispersed in deionized water to prepare an aqueous solution of CTFs; a Ru ion solution containing Ru(III) is added under magnetic stirring, and after vacuum filtration, it is dispersed in deionized water. After reaction, it is centrifuged, washed with deionized water, and after removing the supernatant, the precipitate is precipitated and vacuum dried to obtain powder. Step 2): The powder obtained in Step 1) is redispersed in deionized water, a mercaptopyridine solution is added, the mixture is reacted under stirring, centrifuged and washed, and then vacuum dried to obtain the ruthenium azirconium complex electrochemiluminescent material.

5. The preparation method according to claim 4, characterized in that, In step 1), the Ru(III)-containing Ru ion solution is hexaammineruthenium trichloride.

6. The preparation method according to claim 4, characterized in that, In step 1), the mass concentration ratio of the effective component in the Ru ion solution to the effective component in the CTFs aqueous solution is 1:(1-2).

7. The preparation method according to claim 4, characterized in that, In step 2), the mass concentration ratio of the powder to the active ingredient in the mercaptopyridine solution is 1:(2-4).

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