Preparation method of high-entropy sulfide F3CZ material and application of high-entropy sulfide F3CZ material in electrochemical luminescence detection of sulfadiazine

Abstract

The invention belongs to the technical field of electroluminescence, and particularly relates to a preparation method of a high-entropy sulfide F3CZ material and application of the high-entropy sulfide F3CZ material in electrochemical luminescence detection of sulfadiazine. The preparation method comprises the following steps: dissolving metal nitrates of Fe, Co, Cu, Cr and Zr in isopropanol, carrying out ultrasonic treatment, adding glycerol, transferring a suspension into a high-pressure reaction kettle, heating, filtering and washing in a drying oven to obtain a metal precursor, dissolving the metal precursor and thioacetamide (TAA) in ethanol, stirring, carrying out heating reaction in the drying oven, cooling to room temperature, and carrying out vacuum drying to obtain the Fe-Co-Cu-Cr-Zr composite material. And centrifuging the mixture, washing, and drying in vacuum to obtain the pentabasic high-entropy sulfide (F3CZ). The material has excellent conductivity, chemical stability and multi-electron reaction potential, has good sensitivity, stability and reproducibility when being used for electrochemical luminescence detection of SD, and provides a new scheme for designing a new electrocatalyst to detect SD.

Description

Technical Field

[0001] The present invention belongs to the technical field of electroluminescence, and particularly relates to a preparation method of a high-entropy sulfide F3CZ material and an application thereof in electrochemiluminescence detection of sulfadiazine. Background Art

[0002] Sulfadiazine (SD) is a commonly used antibiotic in clinical practice. It is easily absorbed orally and has limited antibacterial activity against hemolytic streptococci, staphylococci, meningococci, and pneumococci. It is also used to treat respiratory infections, skin and soft tissue infections, intestinal infections, typhoid fever, and plague caused by sensitive bacteria. Furthermore, combined with pyrimethamine, it can be used to treat toxoplasmosis. Therefore, the development of a highly sensitive method for detecting SD is crucial. Currently, methods for determining SD include fluorescence analysis, colorimetry, flow injection analysis, and electrochemiluminescence (ECL). ECL, with its advantages of fast response, high reliability, and high sensitivity, holds broad application prospects. Electrochemiluminescence (ECL) combines the advantages of electrochemistry and spectroscopy, generating light signals electrochemically through the redox reaction of a luminophore. This technique has been widely applied in fields such as single-molecule electrochemical reaction imaging, medical diagnostics, environmental monitoring and evaluation, immunoassays, and drug analysis.

[0003] Luminol, with its non-toxicity and high luminescence efficiency, is one of the most classic and common ECL luminescent materials. To date, most conventional luminol-H₂O₂ ECL systems use H₂O₂ as a co-reactant to generate reactive oxygen species (ROS). ROS react with the electrochemically oxidized luminol anion and exhibit significant anodic emission. This paper establishes a new method for detecting SD using the novel high-entropy sulfide F₃CZ as an effective co-reactant to generate luminol electroluminescence. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for preparing a high-entropy sulfide F3CZ modified electrode with simple preparation method, readily available raw materials, high catalytic efficiency and good selectivity, and its application in electrochemiluminescence detection of SD.

[0005] The technical solution adopted in the present invention is:

[0006] A high-entropy sulfide F3CZ material is a five-element high-entropy sulfide material synthesized using metal nitrates of Fe, Co, Cu, Cr, and Zr and TAA as raw materials.

[0007] The preparation method of the high entropy sulfide F3CZ material comprises the following steps:

[0008] 1) Accurately weigh Fe(NO3)3·9H2O, Co(NO3)2·6H2O, Cu(NO3)2·3H2O, Cr(NO3)3·9H2O, and Zr(NO3)4·5H2O solids, dissolve them in isopropanol, and add glycerol after sonication to obtain a suspension.

[0009] 2) transferring the suspension into a high-pressure reactor, heating it in an oven, filtering and washing it to obtain a metal precursor;

[0010] 3) The metal precursor and TAA were dissolved in ethanol, stirred, heated in an oven for reaction, and then cooled to room temperature. The mixture was centrifuged, washed, and vacuum-dried to obtain a gray-black powder.

[0011] Furthermore, in the above preparation method, in step 1), the weighed amounts of Fe(NO3)3·9H2O, Co(NO3)2·6H2O, Cu(NO3)2·3H2O, Cr(NO3)3·9H2O, and Zr(NO3)4·5H2O are all 0.5 mmol, the amount of isopropanol used is 35 mL, and the amount of glycerol used is 5 mL.

[0012] Furthermore, in the above preparation method, in step 1), the ultrasonic time is 20 minutes.

[0013] Furthermore, in the above preparation method, in step 3), 100 mg of the metal precursor and 167 mg of TAA were dissolved in 50 mL of ethanol.

[0014] Furthermore, in the above preparation method, in step 3), the heating reaction temperature is 160° C., and the heating reaction time is 48 h.

[0015] A high-entropy sulfide F3CZ modified electrode, the preparation method of which comprises the following steps: dissolving 5.0 mg of high-entropy sulfide F3CZ material in 5.0 mL of ethanol, ultrasonically oscillating for 2 hours, then mixing with a 1% by mass Nafion ethanol solution in a volume ratio of 1:1, and then ultrasonicating for 45 minutes to obtain a uniformly dispersed mixed solution; and uniformly applying 5.0 μL of the mixed solution on a pretreated glassy carbon electrode, and allowing the surface to dry.

[0016] Furthermore, in the preparation method of the above-mentioned high-entropy sulfide F3CZ 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 3μm Al2O3 powder, and then the electrode is rinsed from the side with distilled water, placed in a bottle with distilled water and ultrasonicated for 3 minutes, then taken out and rinsed with distilled water, and the surface is blown dry with nitrogen.

[0017] Application of any of the above-mentioned high entropy sulfide F3CZ modified electrodes in electrochemiluminescence detection of sulfadiazine.

[0018] Furthermore, the above application method is as follows: the high entropy sulfide F3CZ modified electrode is used as the working electrode, the counter electrode is a platinum electrode, the reference electrode is an Ag / AgCl reference electrode, the electrolyte is a 100mM phosphate buffer solution with a pH of 9, and the luminescent reagent is 0.1mol L -1 Luminol solution, sulfadiazine solution with a concentration range of 0-1200 ppm, was introduced with a constant O2 flow for 0.5 h before detection. 200 μL of phosphate buffer, 50 μL of luminol solution, and 10 μL of sulfadiazine solution were sequentially added to the electrolytic cell. Electrochemical ECL detection was performed at a scan rate of 50 mV / s in the voltage range of -0.5 to 0 V and a photomultiplier tube of 700 V.

[0019] Furthermore, in the above application, the 0.1 mol L -1 The luminol solution was prepared by accurately weighing 0.443 g of luminol powder and adding it to 25 mL of 0.1 mol L -1 NaOH solution, stirred for 30 min to completely dissolve the powder, and obtained 0.1 mol L -1 Luminol solution can be used after being stored at 4°C in the dark for 7 days.

[0020] The beneficial effects of the present invention are:

[0021] 1. This invention utilizes a synthesized catalyst material modified on a glassy carbon electrode for catalytic reaction. The raw materials are readily available, and the synthesis operation is simple. Prior to ECL measurement, a constant flow of O2 is passed through the electrolyte solution for 0.5 hours to achieve an oxygen-saturated atmosphere, thereby improving the efficiency of the electrocatalytic reaction.

[0022] 2. The catalyst material synthesized in the present invention was used for electrochemiluminescence detection of sulfadiazine. By fitting the variation of ECL intensity with SD concentration, a linear calibration curve was obtained with a correlation coefficient of 0.996 and a detection limit of 1.96×10 -5 μM (S / N=3).

[0023] 3. The ECL luminescence intensity of the synthesized catalyst material in a PBS solution (pH = 9) containing 100 mM luminol was very stable over a potential range of -0.5 V to 0 V. The calculated relative standard deviation (RSD) was 4.5%, demonstrating good ECL stability and reproducibility. The F3CZ catalyst obtained in this invention has promising application prospects in the electrochemiluminescence detection of sulfadiazine. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1This is the SEM (A) and EDS morphology characterization image (B) of the high entropy sulfide F3CZ material prepared in Example 1.

[0025] Figure 2 3CZ is the XRD pattern of the high entropy sulfide F3CZ material powder prepared in Example 1.

[0026] Figure 3 is the C of the high entropy sulfide F3CZ modified electrode in Example 2 dl picture.

[0027] Figure 4 This is the electrochemical impedance spectroscopy (EIS) graph of the high entropy sulfide F3CZ modified electrode in Example 2.

[0028] Figure 5 This is a comparison chart of the ECL intensity of the high entropy sulfide F3CZ modified electrode in Example 2 in O2, air and N2 gas.

[0029] Figure 6 This is the stability curve of the high entropy sulfide F3CZ luminol electrochemiluminescence system scan in Example 2.

[0030] Figure 7 This is a comparison chart of the ECL intensity of the high-entropy sulfide F3CZ / GCE in Example 2 in SD solutions of different concentrations.

[0031] Figure 8 is the ΔI and lgC in Example 2 SD The linear logarithmic plot (ΔI=I0-I, where I0 and I are the ECL intensities in the absence and presence of SD, respectively, C SD is SD concentration). DETAILED DESCRIPTION

[0032] Example 1 Preparation of high entropy sulfide F3CZ modified electrode

[0033] (1) The preparation method is as follows:

[0034] 1) Pretreatment of the glassy carbon electrode: Polish the bare glassy carbon electrode to a mirror finish using 3μm Al2O3 powder. Rinse the electrode from the side with distilled water, place it in a bottle of distilled water and ultrasonicate for 3 minutes, then remove it and rinse it with distilled water again. Dry the surface with nitrogen and then use cyclic voltammetry (CV) to scan at a scan rate of 0.03V / s in 15mL of 1mmol / L potassium ferricyanide solution. The electrode is considered qualified when the potential difference (ΔEp) between the oxidation peak and the reduction peak is 70-80mV, indicating good cleanliness. Rinse it with water again, dry it with nitrogen, and set aside. If it fails, re-polish it and use CV characterization until the qualified potential difference is achieved.

[0035] 2) Preparation of high-entropy sulfide F3CZ materials: 0.5 mmol of each solid Fe(NO3)3·9H2O, Co(NO3)2·6H2O, Cu(NO3)2·3H2O, Cr(NO3)3·9H2O, and Zr(NO3)4·5H2O were dissolved in 35 mL of isopropanol. After sonication for 20 min, 5 mL of glycerol was added. The resulting suspension was then transferred to a 100 mL autoclave and heated in an oven at 150°C for 10 h. The metal precursors were filtered and washed to obtain the metal precursors. 100 mg of the metal precursors and 167 mg of thioacetamide (TAA) were dissolved in 50 mL of ethanol and stirred for 30 min. The mixture was then heated in an oven at 160°C for 48 h. After cooling to room temperature, the mixture was centrifuged, washed, and vacuum-dried to obtain a gray-black powder.

[0036] 3) Preparation of a high-entropy sulfide F3CZ-modified electrode: 5.0 mg of high-entropy sulfide F3CZ powder was dissolved in 5.0 mL of ethanol and ultrasonicated for 2 hours. The mixture was then mixed with a 1% Nafion ethanol solution at a 1:1 volume ratio and ultrasonicated for 45 minutes to obtain a uniformly dispersed mixed solution. 5.0 μL of the mixed solution was evenly applied to a pretreated glassy carbon electrode and allowed to dry before use. This electrode was designated F3CZ-48.

[0037] In addition, according to the above preparation method, only the heating reaction time was changed to 8h, 24h, and 72h, respectively, to prepare F3CZ-8, F3CZ-24, and F3CZ-72 modified electrodes.

[0038] (2) Test results

[0039] Figure 1 This is a scanning electron microscope image and EDS element mapping of the F3CZ material powder prepared in Example 1. The image shows that the matrix is ​​a gray continuous phase with dispersed black particles as sulfides. The Fe, Co, Cu, Cr, and Zr elements are evenly distributed, showing good dispersion, which is conducive to full exposure of the active sites. Figure 2 The XRD spectra of the F3CZ material powder prepared in Example 1 are compared with the standard card (Cu 0.4 Fe 0.6 )S2 PDF#82-0234) alignment. The results show that Fe and Cu are the main active components of F3CZ, and the highest peak intensity is observed at a reaction time of 48 h, indicating a significant increase in crystallinity and grain size. To shorten the reaction time and reduce energy consumption, 48 h was selected as the optimal reaction condition.

[0040] Example 2 Application of high entropy sulfide F3CZ modified electrode in electrochemiluminescence detection of SD

[0041] 0.1 mol L -1 Preparation of luminol solution: First prepare 100 mL of 0.1 mol L -1 NaOH solution, accurately weigh 0.443g of luminol powder using an analytical balance and add it to 25mL of 0.1mol L -1 NaOH solution, stirred for 30 min to completely dissolve the powder, and obtained 0.1 mol L -1 Luminol solution can be used after being stored at 4°C in the dark for 7 days.

[0042] Test method: The high entropy sulfide F3CZ modified electrode prepared in Example 1 was used as the working electrode, the counter electrode was a platinum electrode, the reference electrode was an Ag / AgCl reference electrode, the electrolyte was a 100 mM phosphate buffer solution with a pH of 9, and the luminescent reagent was 0.1 mol L -1 Luminol solution was used to prepare a sulfadiazine solution with a concentration range of 0-1200 ppm. A constant O2 flow was introduced for 0.5 h before detection. 200 μL of phosphate buffer, 50 μL of luminol solution, and 10 μL of sulfadiazine solution were added to the electrolytic cell in sequence. Electrochemical ECL detection was performed at a scan rate of 50 mV / s in the voltage range of -0.5 to 0 V and a photomultiplier tube of 700 V.

[0043] Electrochemically active surface area (ECSA) is an important factor affecting the performance of catalysts. ECSA is the electrochemical double layer capacitance (C dl ) is determined by the slope of the linear fit between current density and scan rate. Figure 3 As shown, the C of F3CZ-8, F3CZ-24, F3CZ-48, F3CZ-72 dl 0.57, 0.80, 0.89, and 0.64 mF cm, respectively -2 , indicating that the F3CZ-48 modified electrode has a larger exposed surface area in the electrolyte, which helps to promote the transfer of electrons on the catalyst surface. The charge transfer ability of F3CZ was studied by electrochemical impedance spectroscopy (EIS). Figure 4 In the figure, the smaller the semicircle, the smaller the charge transfer resistance and the stronger the charge transfer ability.

[0044] Example 3 Electrochemiluminescence detection of high entropy sulfide F3CZ modified electrode under different atmospheres

[0045] Figure 5 shows the ECL intensity of the F3CZ-48 modified electrode in O2, air, and N2 atmospheres. Under O2-saturated conditions, the ECL intensity reaches its highest. This result demonstrates that O2 is a key species in the electrocatalytic reaction, and its participation in the ORR reaction provides the necessary ROS for the oxidation of luminol, thereby maximizing the ECL signal.

[0046] Stability test such as Figure 6 As shown in the figure, the ECL intensity of the phosphate buffer solution (pH=9) containing luminol is very stable under continuous scanning in the potential range of -0.5V to 0V. The calculated relative standard deviation (RSD) is 4.5%, indicating that the system has good ECL stability and reproducibility.

[0047] Example 4 High entropy sulfide F3CZ modified electrode for electrochemiluminescence detection of SD

[0048] Depend on Figure 7 and Figure 8 It can be seen that with the change of SD concentration, the ECL intensity on the F3CZ modified electrode (F3CZ / GCE) changes, which can be expressed by the equation ΔI = 8205.7logC SD +26935 describes (ΔI=I0-I, where I0 and I are the ECL intensities in the absence and presence of SD, respectively, C SD is the SD concentration). The ECL intensity decreases monotonically with the increase of SD concentration, and the correlation coefficient (R 2 ) was 0.996, which showed that there was a very strong linear correlation between ECL intensity and SD concentration. In addition, the detection limit of SD was 1.96×10 -5 μM, which is the lowest concentration measured at a signal-to-noise ratio (S / N) of 3.

[0049] In summary, the high-entropy sulfide F3CZ modified electrode of the present invention has good sensitivity, selectivity, stability, and reproducibility, as well as excellent electrochemiluminescence performance, and has good development prospects in the field of electrochemiluminescence detection of sulfadiazine.

Claims

1. A high entropy sulfide F3CZ material, characterized in that: The high entropy sulfide F3CZ material is a five-element high entropy sulfide material synthesized using metal nitrates of Fe, Co, Cu, Cr, and Zr and TAA as raw materials.

2. The method for preparing the high entropy sulfide F3CZ material according to claim 1, characterized in that: The following steps are involved: 1) Accurately weigh Fe(NO3)3·9H2O, Co(NO3)2·6H2O, Cu(NO3)2·3H2O, Cr(NO3)3·9H2O, and Zr(NO3)4·5H2O solids, dissolve them in isopropanol, and add glycerol after sonication to obtain a suspension. 2) transferring the suspension into a high-pressure reactor, heating it in an oven, filtering and washing it to obtain a metal precursor; 3) The metal precursor and TAA were dissolved in ethanol, stirred, heated in an oven for reaction, and then cooled to room temperature. The mixture was centrifuged, washed, and vacuum-dried to obtain a gray-black powder.

3. The preparation method according to claim 2, characterized in that In step 1), the weighed amounts of Fe(NO3)3·9H2O, Co(NO3)2·6H2O, Cu(NO3)2·3H2O, Cr(NO3)3·9H2O, and Zr(NO3)4·5H2O are all 0.5 mmol, the amount of isopropanol used is 35 mL, and the amount of glycerol used is 5 mL; the ultrasonic time is 20 min.

4. The preparation method according to claim 2, characterized in that In step 3), 100 mg of metal precursor and 167 mg of TAA were dissolved in 50 mL of ethanol.

5. The preparation method according to claim 2, characterized in that In step 3), the heating reaction temperature is 160° C. and the heating reaction time is 48 h.

6. A high entropy sulfide F3CZ modified electrode, characterized in that The preparation method comprises the following steps: dissolving 5.0 mg of the high-entropy sulfide F3CZ material according to claim 1 in 5.0 mL of ethanol, ultrasonically oscillating for 2 hours, then mixing with a 1% mass fraction Nafion ethanol solution in a volume ratio of 1:1, and then ultrasonicating for 45 minutes to obtain a uniformly dispersed mixed solution; evenly applying 5.0 μL of the mixed solution on a pretreated glassy carbon electrode, and allowing its surface to dry.

7. A high entropy sulfide F3CZ modified electrode according to claim 6, characterized in that 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, and then the electrode is rinsed from the side with distilled water. After being placed in a bottle of distilled water and ultrasonicated for 3 minutes, it is taken out and rinsed with distilled water again, and the surface is blown dry with nitrogen.

8. Use of the high entropy sulfide F3CZ modified electrode according to claim 6 or 7 in electrochemiluminescence detection of sulfadiazine.

9. The use according to claim 8, characterized in that The method is as follows: a high entropy sulfide F3CZ modified electrode is used as the working electrode, a platinum electrode is used as the counter electrode, an Ag / AgCl reference electrode is used as the reference electrode, a 100 mM phosphate buffer solution with a pH of 9 is used as the electrolyte, and a luminescent reagent is used as 0.1 mol L -1 Luminol solution, sulfadiazine solution with a concentration range of 0-1200 ppm, was introduced with a constant O2 flow for 0.5 h before detection. 200 μL of phosphate buffer, 50 μL of luminol solution, and 10 μL of sulfadiazine solution were sequentially added to the electrolytic cell. Electrochemical ECL detection was performed at a scan rate of 50 mV / s in the voltage range of -0.5 to 0 V and a photomultiplier tube of 700 V.

10. The use according to claim 9, characterized in that The 0.1 mol L -1 The luminol solution was prepared by accurately weighing 0.443 g of luminol powder and adding it to 25 mL of 0.1 mol L -1 NaOH solution, stirred for 30 min to completely dissolve the powder, and obtained 0.1 mol L -1 Luminol solution can be used after being stored at 4°C in the dark for 7 days.

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