Preparation method of high-entropy MOF material and application thereof in electrochemiluminescence detection of rifampicin
By modifying the electrode with high-entropy MOF material HE-ATA, the problem of insufficient sensitivity in the electrochemiluminescence detection of rifampicin was solved, and efficient and stable rifampicin detection was achieved with low detection limit and good linearity and reproducibility of detection results.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- LIAONING UNIVERSITY
- Filing Date
- 2026-02-13
- Publication Date
- 2026-06-02
AI Technical Summary
Existing electrochemiluminescence methods for detecting rifampicin lack sufficient sensitivity, making it difficult to achieve efficient and stable detection.
High-entropy MOF material HE-ATA was used as a co-reactant for luminol and modified the electrode for electrochemiluminescence detection. High-entropy MOF material was prepared by synthesizing metal nitrates of Fe, Co, Cu, Cr and Zn and reacting them with ATA. The electrode was then modified on a glassy carbon electrode, and the catalytic efficiency was improved by combining it with an O2 saturated atmosphere.
Highly sensitive rifampicin detection was achieved with a detection limit of 3.3 × 10⁻⁶ µM and a correlation coefficient of 0.996. It exhibits good stability and reproducibility, and the ECL signal intensity is linearly correlated with the rifampicin concentration.
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Figure CN122127611A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of electroluminescence technology, specifically relating to a method for preparing high-entropy MOF materials and their application in the electrochemiluminescence detection of rifampicin. Background Technology
[0002] Rifampin (RIF) is a broad-spectrum antibiotic and one of the core drugs in anti-tuberculosis treatment. Its mechanism of action involves inhibiting bacterial RNA polymerase, blocking nucleic acid synthesis, and it has a strong bactericidal effect against Mycobacterium tuberculosis, Mycobacterium leprae, and other bacteria. It can also be used to treat infections caused by Staphylococcus aureus and other bacteria. Rifampin is rapidly absorbed orally, widely distributed in the body, and is mainly metabolized by the liver. Clinically, it is often used in combination with isoniazid to treat pulmonary tuberculosis and extrapulmonary tuberculosis, requiring regular, full-course medication to prevent drug resistance. Therefore, establishing a highly sensitive method for detecting RIF is crucial. Currently, methods for RIF determination include fluorescence analysis, colorimetry, flow injection analysis, and electrochemiluminescence (ECL). Among these, ECL has broad application prospects due to its fast response, high reliability, and high sensitivity. Electrochemiluminescence combines the advantages of electrochemistry and spectroscopy, generating light signals electrochemically through the redox reaction of a luminescent material. This technology has been widely applied in single-molecule electrochemical reaction imaging, medical diagnosis, environmental monitoring and assessment, immunoassay, and drug analysis. Luminol, with its advantages of being non-toxic and having high luminous efficiency, is one of the most classic and common ECL luminescent materials. To date, most traditional luminol-H₂O₂ ECL systems use H₂O₂ as a classic co-reactant to generate reactive oxygen species (ROS). The ROS react with electrochemically oxidized luminol anions, exhibiting significant anodic emission. This invention utilizes the novel high-entropy MOF material HE-ATA as an effective co-reactant for luminol electroluminescence, establishing a new method for detecting reactive oxygen species (RIFs). Summary of the Invention
[0003] The purpose of this invention is to provide a method for preparing a high-entropy MOF material HE-ATA modified electrode that is simple to prepare, has readily available raw materials, high catalytic efficiency and good selectivity, and its application in electrochemiluminescence detection of RIF.
[0004] The technical solution adopted in this invention is:
[0005] A high-entropy MOF material is a pentagonal high-entropy MOF material HE-ATA, synthesized from metal nitrates of Fe, Co, Cu, Cr, and Zn and ATA as raw materials.
[0006] Furthermore, the above-mentioned method for preparing a high-entropy MOF material includes the following steps: accurately weighing Fe(NO3)3·9H2O, Co(NO3)2·6H2O, Cu(NO3)2·3H2O, Cr(NO3)3·9H2O, and Zn(NO3)2·6H2O solids, and dissolving them sequentially in a mixed solution of DMF, ethanol, and water, stirring to dissolve; then adding diaminoterephthalic acid (ATA) and dissolving it, transferring the resulting suspension to a high-pressure reactor, heating and reacting it in an oven, cooling it to room temperature, centrifuging the mixture, washing it, and vacuum drying it to obtain a gray-black powder.
[0007] Furthermore, in the above preparation method, Fe(NO3)3·9H2O, Co(NO3)2·6H2O, Cu(NO3)2·3H2O, Cr(NO3)3·9H2O, and Zn(NO3)2·6H2O are all dissolved in a mixed solution of 70 mL DMF, 6 mL ethanol, and 6 mL water at a concentration of 5 mmol, and the amount of ATA added is 39 g.
[0008] Furthermore, in the above preparation method, the stirring time is 8 hours.
[0009] Furthermore, in the above preparation method, the heating reaction temperature is 150 °C and the reaction time is 24 h.
[0010] A high-entropy MOF material HE-ATA modified electrode is prepared as follows: 5.0 mg of the HE-ATA powder described in claim 1 is dissolved in 5.0 mL of ethanol, ultrasonically vibrated for 2 h, and then mixed with 1% Nafion ethanol solution at a volume ratio of 1:1. The mixture is then ultrasonicated for 50 min to obtain a uniformly dispersed mixed solution. 5.0 µL of the mixed solution is uniformly coated on a pretreated glassy carbon electrode and allowed to dry before use.
[0011] The above-mentioned high-entropy MOF material HE-ATA modified electrode, the pretreatment method of the glassy carbon electrode is as follows: the bare glassy carbon electrode is ground and polished to a mirror surface with 3 μm Al2O3 powder, then the electrode is rinsed from the side with distilled water, placed in a bottle with distilled water and sonicated for 3 min, and then taken out and rinsed with distilled water again.
[0012] The application of the high-entropy MOF material HE-ATA modified electrode mentioned above in electrochemiluminescence detection of RIF.
[0013] Further, the above application is carried out as follows: The high-entropy MOF material HE-ATA modified electrode is used as the working electrode, the counter electrode is a platinum sheet electrode, the reference electrode is an Ag / AgCl electrode, and the electrolyte is a phosphate buffer solution (PBS) with 100 mM luminol at pH=9. Before the test, a constant flow of O2 is introduced for 0.5 h. The PBS solution containing 100 mM luminol and RIF solutions of different concentrations are added to the electrolytic cell in sequence. Electrochemical and ECL tests are performed at a scan rate of 50 mV / s under the conditions of an 800 V photomultiplier tube within a voltage range of -0.5 to 0.5 V. Different concentrations of RIF correspond to different electrochemiluminescence (ECL) intensities.
[0014] Furthermore, in the above application, the preparation method of the luminol solution is as follows: first, prepare 100 mL of 0.1 mol / L luminol solution. -1 NaOH solution: Accurately weigh 0.443 g of luminol powder using an analytical balance and add it to 25 mL of 0.1 mol / L solution. -1 The powder was completely dissolved in NaOH solution by stirring for 30 min, yielding 0.1 mol L. -1 Luminol solution can be used after being stored at 4 ℃ in the dark for 7 days.
[0015] The beneficial effects of this invention are:
[0016] 1. This invention catalyzes reactions by modifying synthesized catalyst materials onto glassy carbon electrodes. The raw materials are simple and readily available, and the synthesis operation is easy. Before ECL measurement, a constant flow of O2 is passed through the electrolyte solution for 0.5 h to achieve a saturated oxygen atmosphere, which improves the efficiency of the electrocatalytic reaction.
[0017] 2. The catalyst material synthesized in this invention is used for the electrochemiluminescence detection of rifampicin. By fitting the change of ECL intensity with RIF concentration, a linear calibration curve was obtained with a correlation coefficient of 0.996 and a detection limit of 3.3 × 10⁻⁶. -6 µM (S / N=3).
[0018] 3. The ECL luminescence intensity of the catalyst material synthesized in this invention is very stable when continuously scanned in a PBS solution containing 100 mM luminol (pH=9) within a potential range of -0.5 V to 0.5 V. The calculated relative standard deviation (RSD) is 3.9%, indicating that the system has good ECL stability and reproducibility. The HE-ATA catalyst obtained in this invention has good application prospects in the field of electrochemiluminescence detection of rifampicin. Attached Figure Description
[0019] Figure 1This is a SEM characterization image of the high-entropy MOF material HE-ATA powder prepared in Example 1.
[0020] Figure 2 This is the XRD pattern of HE-ATA powder, a high-entropy MOF material prepared in Example 1.
[0021] Figure 3 The C of the high-entropy MOF material HE-ATA modified electrode in Example 2 is... dl picture.
[0022] Figure 4 This is the EIS image of the HE-ATA modified electrode of the high-entropy MOF material in Example 2.
[0023] Figure 5 The ECL intensity of the HE-ATA modified electrode of the high-entropy MOF material in Example 2 is shown under different conditions.
[0024] Figure 6 The image shows the stability curve of the HE-ATA luminol electrochemiluminescence system of the high-entropy MOF material in Example 2.
[0025] Figure 7 This is a comparison of the ECL intensity of the high-entropy MOF material HE-ATA / GCE in RIF solutions of different concentrations in Example 2.
[0026] Figure 8 In Example 2, ΔI and lgC RIF The linear logarithmic plot (ΔI=I0-I, where I0 and I are the ECL intensities when RIF is absent and present, respectively). Detailed Implementation
[0027] Example 1: Fabrication of HE-ATA-modified electrode made of high-entropy MOF material
[0028] (a) The preparation method is as follows:
[0029] 1) Pretreatment of glassy carbon electrode: The bare glassy carbon electrode was ground and polished to a mirror finish using 3 μm Al2O3 powder. Then, the electrode was rinsed from the side with distilled water, placed in a bottle containing distilled water, and sonicated for 3 min. It was then removed and rinsed again with distilled water. The surface was dried with nitrogen gas, and then CV was performed in 15 mL of 1 mmol / L potassium ferricyanide solution at a scan rate of 0.03 V / s. A potential difference (ΔEp) between the oxidation peak and the reduction peak was considered acceptable, indicating good electrode cleanliness. After rinsing with water and drying with nitrogen gas, it was ready for use. If it did not meet the requirements, it was repolished and characterized using CV until the acceptable potential difference was achieved.
[0030] 2) Preparation of high-entropy MOF material: Fe(NO3)3·9H2O, Co(NO3)2·6H2O, Cu(NO3)2·3H2O, Cr(NO3)3·9H2O, and Zn(NO3)2·6H2O solids were dissolved sequentially at a concentration of 5 mmol in a mixed solution of 70 mL DMF, 6 mL ethanol, and 6 mL water. After stirring for 8 h, 39 g of diaminoterephthalic acid (ATA) was added and dissolved. The resulting suspension was then transferred to a 100 mL high-pressure reactor and heated in an oven at 150 ℃ for 24 h. After cooling to room temperature, the mixture was centrifuged, washed, and vacuum dried to obtain a gray-black powder, which is the high-entropy MOF material HE-ATA.
[0031] 3) Preparation of HE-ATA modified electrode using high-entropy MOF material: 5.0 mg of HE-ATA powder was dissolved in 5.0 mL of ethanol and sonicated for 2 h. Then, it was mixed with 1% Nafion ethanol solution at a 1:1 volume ratio and sonicated for 50 min to uniformly disperse the mixture. 5.0 µL of the mixture was uniformly coated onto the pre-treated glassy carbon electrode and allowed to air dry before use.
[0032] (II) Test Results
[0033] Figure 1 The images show scanning electron microscope (SEM) images of the HE-ATA catalyst powder prepared in Example 1. The powder exhibits a large, blocky structure with an uneven surface, showing obvious striations, cracks, and micro-protrusions, indicating that it is assembled from smaller units. The structure exhibits a certain degree of "layered stacking" characteristics. Additionally, the surface contains a small number of pores or defects, which may be porous structures formed during the synthesis process. These morphologies suggest that during the nucleation and growth of HE-ATA, crystal nuclei are more likely to aggregate into large-sized bulk particles rather than dispersed nanoparticles. Figure 2 The XRD patterns of the HE-ATA catalyst powder prepared in Example 1 are shown. HE-ATA exhibits sharp and high-intensity diffraction peaks in the 10°-30° range, consistent with Bragg diffraction characteristics of crystals, indicating a well-defined crystalline structure. HE-PMDA shows a weak and broad diffuse peak near 45°, characteristic of amorphous materials, indicating disordered structural units and a lack of long-range order. HE-TA exhibits low-intensity and broad peaks, suggesting low crystallinity or amorphous characteristics, with only short-range structural order. This difference stems from the different coordination modes of the ligands with the metal nodes: ATA ligands more readily form a regular crystal framework with multi-metal nodes, while PMDA and TA ligands may hinder the formation of long-range ordered structures due to steric hindrance and other factors.
[0034] Example 2: Application of HE-ATA modified electrode with high entropy MOF material in electrochemiluminescence detection of RIF
[0035] Test method: The prepared HE-ATA modified glassy carbon electrode (HE-ATA / GCE) was used as the working electrode.
[0036] Electrochemically active specific surface area (ECSA) is an important factor affecting catalyst performance. ECSA is measured using the electrochemical double-layer capacitance (C0). dl The electrochemical performance of HE-ATA materials was determined by linear fitting of current density and scan rate, and the slope was obtained. To demonstrate the excellent electrochemical performance of HE-ATA materials, HE-TA materials using terephthalic acid as a ligand and HE-PMDA materials using pyromellitic anhydride as a ligand were synthesized (other synthesis steps were the same, only the ligands were changed in equimolar amounts). The electrochemical performance of the three materials synthesized with different ligands was compared. Figure 3 As shown, C of HE-ATA, HE-PMDA, HE-TA dl The values were 0.64, 0.15, and 0.03 mFcm, respectively. -2 This indicates that the HE-ATA catalyst electrode has a large exposed surface area in the electrolyte, which helps to promote electron transport on the catalyst surface. The charge transfer capability of HE-ATA was investigated by electrochemical impedance spectroscopy (EIS). Figure 4 In this context, the smaller the semicircular arc, the smaller the charge transfer resistance and the stronger the charge transfer capability.
[0037] Figure 5 shows the ECL intensity of the modified electrode under different conditions. The ECL intensity was strongest when luminol and HE-ATA were present simultaneously. This result demonstrates the electrocatalytic effect of HE-ATA on the reaction system, thereby maximizing the ECL signal.
[0038] Stability testing such as Figure 6 As shown, the ECL intensity of the PBS solution containing 100 mM luminol (pH=9) was very stable during continuous scanning in the potential range of -0.5 V to 0.5 V. The calculated relative standard deviation (RSD) was 3.9%, indicating that the system has good ECL stability and reproducibility.
[0039] To perform ECL detection of RIF, a luminol solution was first prepared by mixing 100 mL of 0.1 mol / L luminol solution. -1 NaOH solution: Accurately weigh 0.443 g of luminol powder using an analytical balance and add it to 25 mL of 0.1 mol / L solution. -1 The powder was stirred in NaOH solution for 30 minutes until completely dissolved, yielding 0.1 mol L. -1The luminol solution was stored at 4 °C in the dark for 7 days before use. A high-entropy MOF material HE-ATA modified electrode was used as the working electrode, a platinum sheet electrode as the counter electrode, and an Ag / AgCl electrode as the reference electrode. The electrolyte was a phosphate-buffered saline (PBS) solution with 100 mM luminol at pH 9. A constant O2 flow was introduced for 0.5 h before testing. PBS solution containing 100 mM luminol and different concentrations of RIF solution were added sequentially to the electrolytic cell. Electrochemical and ECL tests were performed at a scan rate of 50 mV / s within a voltage range of -0.5 to 0.5 V and under 800 V photomultiplier tube conditions. Different concentrations of RIF corresponded to different electrochemiluminescence (ECL) intensities. Figure 7 and Figure 8 It can be seen that the change in ECL intensity on HE-ATA / GCE with the change in RIF concentration can be expressed by the equation ΔI=805.1 logC. RIF +3458.5 Description (ΔI=I0-I, where I0 and I are the ECL intensities in the absence and presence of RIF, respectively). ECL intensity decreases monotonically with increasing RIF concentration, and the correlation coefficient (R) 2 The correlation coefficient (RCC) was 0.996, indicating a very strong linear correlation between ECL intensity and RIF concentration. Furthermore, the limit of detection (LOD) for RIF was 3.3 × 10⁻⁶. -6 μM, which is the lowest concentration measured at a signal-to-noise ratio (S / N) of 3.
[0040] In summary, the high-entropy MOF material HE-ATA modified electrode of this invention exhibits good sensitivity, selectivity, stability, and reproducibility, as well as excellent electrochemiluminescence performance. It shows promising development potential in the field of electrochemiluminescence detection of rifampicin.
Claims
1. A high-entropy MOF material, characterized in that, HE-ATA is a five-element high-entropy MOF material synthesized from metal nitrates of Fe, Co, Cu, Cr, and Zn and ATA as raw materials.
2. The method for preparing a high-entropy MOF material according to claim 1, characterized in that, The process includes the following steps: accurately weigh the solids Fe(NO3)3·9H2O, Co(NO3)2·6H2O, Cu(NO3)2·3H2O, Cr(NO3)3·9H2O, and Zn(NO3)2·6H2O, and dissolve them sequentially in a mixed solution of DMF, ethanol, and water, stirring until dissolved; then add ATA and dissolve it, transfer the resulting suspension to a high-pressure reactor, heat it in an oven to react, cool it to room temperature, centrifuge the mixture, wash it, and vacuum dry it to obtain a gray-black powder.
3. The preparation method according to claim 2, characterized in that, Fe(NO3)3·9H2O, Co(NO3)2·6H2O, Cu(NO3)2·3H2O, Cr(NO3)3·9H2O, and Zn(NO3)2·6H2O were all dissolved in a mixed solution of 70 mL DMF, 6 mL ethanol, and 6 mL water at a concentration of 5 mmol. The amount of ATA added was 39 g.
4. The preparation method according to claim 2, characterized in that, The stirring time is 8 hours.
5. The preparation method according to claim 2, characterized in that, The heating reaction temperature is 150 °C, and the reaction time is 24 h.
6. A high-entropy MOF material HE-ATA modified electrode, characterized in that, The preparation method is as follows: 5.0 mg of the HE-ATA powder described in claim 1 is dissolved in 5.0 mL of ethanol, ultrasonically vibrated for 2 h, and then mixed with 1% Nafion ethanol solution at a volume ratio of 1:1, and then ultrasonicated for 50 min to obtain a uniformly dispersed mixed solution; 5.0 µL of the mixed solution is uniformly coated on the pretreated glassy carbon electrode, and the surface is allowed to dry before use.
7. The high-entropy MOF material HE-ATA modified electrode according to claim 6, characterized in that, The pretreatment method for the glassy carbon electrode is as follows: the bare glassy carbon electrode is ground and polished to a mirror finish with 3 μm Al2O3 powder, then the electrode is rinsed from the side with distilled water, placed in a bottle with distilled water and sonicated for 3 minutes, and then rinsed with distilled water again.
8. The application of the high-entropy MOF material HE-ATA modified electrode as described in claim 6 or 7 in electrochemiluminescence detection of RIF.
9. The application according to claim 8, characterized in that, The application method is as follows: The high-entropy MOF material HE-ATA modified electrode is used as the working electrode, the counter electrode is a platinum sheet electrode, the reference electrode is an Ag / AgCl electrode, and the electrolyte is a PBS solution of 100 mM luminol at pH=9. Before the test, a constant flow of O2 is introduced for 0.5 h. The PBS solution containing 100 mM luminol and RIF solutions of different concentrations are added to the electrolytic cell in sequence. Electrochemical and ECL tests are performed at a scan rate of 50 mV / s under the conditions of an 800 V photomultiplier tube within a voltage range of -0.5 to 0.5 V. Different concentrations of RIF correspond to different electrochemiluminescence (ECL) intensities.
10. The application according to claim 9, characterized in that, The method for preparing the luminol solution is as follows: First, prepare 100 mL of 0.1 mol / L luminol solution. -1 NaOH solution: Accurately weigh 0.443 g of luminol powder using an analytical balance and add it to 25 mL of 0.1 mol / L NaOH solution. -1 The powder was completely dissolved in NaOH solution by stirring for 30 min, yielding 0.1 mol L. -1 Luminol solution can be used after being stored at 4 ℃ in the dark for 7 days.