A Raman detection method for hydrogen peroxide based on Au-Ag@manganese dioxide nanomaterials

Abstract

The present invention provides a Raman detection method of hydrogen peroxide based on Au-Ag@manganese dioxide nanomaterials, and belongs to the technical field of Raman spectroscopy analysis. The present invention comprises preparing Au-AgJanusNPs by a ligand MBIA-guided directional growth method, growing a MnO2 shell around it, and synthesizing an Au-Ag@MnO2 nanomaterial. The prepared Au-Ag@MnO2 nanomaterial hinders the release of the SERS signal of MBIA. In the presence of H2O2, the MnO2 shell is consumed, resulting in a linear enhancement of the SERS signal of MBIA as the logarithmic value of the concentration of H2O2 increases. The Raman sensor does not require additional modification of the Raman beacon, and can achieve sensitive and accurate detection of H2O2.

Description

Technical Field

[0001] The invention belongs to the technical field of Raman analysis, and in particular refers to a Raman detection method for hydrogen peroxide based on Au-Ag@manganese dioxide nanomaterials. Background Art

[0002] H2O2 has strong redox properties and plays an important role in biological systems as the main reactive oxygen species. H2O2 can induce oxidative stress and is associated with many diseases, including organ system function decline, tumors, cancer, Alzheimer's disease and other related neurodegenerative diseases. Therefore, monitoring H2O2 is important for preventing human tissue damage.

[0003] Traditional methods for detecting H2O2 include chromatography, colorimetry, fluorescence, electrochemistry, magnetic biosensing, and surface-enhanced Raman scattering. Currently, these detection techniques are usually complex, time-consuming, and often require cumbersome operations or expensive instruments, which greatly limits their widespread application. Raman spectroscopy has the advantages of strong selectivity, rich spectral information, and high resolution. Therefore, it is particularly important to construct a new H2O2 detection method based on Raman spectroscopy. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a Raman detection method for hydrogen peroxide based on Au-Ag@manganese dioxide nanomaterials. A nanoprobe with a good and stable SERS signal is the basis for realizing Raman detection. In the present invention, the ligand MBIA not only participates in the synthesis reaction, but also has a strong and stable SERS signal, and no additional modification of the Raman beacon is required, thereby facilitating a more sensitive quantitative detection of H2O2.

[0005] The object of the present invention is to provide a Raman detection method for H2O2 based on Au-Ag@MnO2 nanomaterials, comprising the following steps:

[0006] S1, dissolving AuNPs in water, adding 2-mercaptobenzimidazole-5-carboxylic acid (MBIA), incubating at 50-70° C. for 1-3 hours, adding hydroquinone and a silver source, standing to obtain Au-Ag Janus NPs, and redispersing in water to obtain Au-AgJanus NPs; the MBIA covers the surface of Au in the Au-Ag Janus NPs material;

[0007] S2, after mixing the Au-Ag Janus NPs solution in S1 with KMnO4, polyacrylic acid is added dropwise and mixed to obtain Au-Ag@MnO2 nanomaterials;

[0008] S3, mixing the Au-Ag@MnO2 nanomaterial obtained in S2 with the H2O2 solution, separating the solid and the liquid to obtain the solid phase, detecting the Raman intensity of the solid phase, and realizing the qualitative or quantitative detection of H2O2.

[0009] In one embodiment of the present invention, the concentration of the silver source in S1 is 1-2 mM.

[0010] In one embodiment of the present invention, the MBIA concentration in S1 is 1-2 mM.

[0011] In one embodiment of the present invention, the concentration of hydroquinone in S1 is 10-20 mM.

[0012] In one embodiment of the present invention, the concentration of polyacrylic acid in S2 is 1%-2% (w / v).

[0013] In one embodiment of the present invention, the mass ratio of Au-Ag Janus NPs to KMnO4 in the Au-Ag Janus NPs solution in S2 is 0.5:0.9 to 0.5:1.

[0014] In one embodiment of the present invention, S3 further comprises washing the solid phase with a 70-80% ethanol aqueous solution.

[0015] In one embodiment of the present invention, the preparation method of the standard curve for quantitative detection in S3 is as follows: the Au-Ag@MnO2 nanomaterial is mixed with H2O2 solutions of different concentrations, the solid-liquid separation is performed to obtain the solid phase, and the Raman intensity of the solid phase is detected to obtain the standard curve with the logarithm of H2O2 concentration as the horizontal axis and the Raman intensity of 1278 cm -1 The Raman intensity at the position is taken as the ordinate, and a standard curve for quantitative detection is obtained.

[0016] In one embodiment of the present invention, 785 nm Ar + The solid phase Raman intensity is detected by an ion laser source.

[0017] In one embodiment of the present invention, the H2O2 solution has different concentrations of 0.01-100 nM.

[0018] The above technical solution of the present invention has the following advantages compared with the prior art:

[0019] The method provided by the present invention can detect the concentration of H2O2 in the sample by Raman detection, making the detection more convenient. -1 The linear relationship between the Raman intensity at and the logarithm of the H2O2 concentration improves the accuracy of the detection. The method of H2O2 Raman detection of Au-Ag@MnO2 nanomaterials in the present invention is expected to detect the concentration of H2O2 in life and health, and has a very broad application prospect. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments of the present invention in conjunction with the accompanying drawings, wherein

[0021] Figure 1 This is a transmission electron microscope image of the Au-Ag@MnO2 nanomaterial (2h, 1h) according to Example 2 of the present invention.

[0022] Figure 2 In Example 2 of the present invention, when H2O2 of different concentrations is present, at 1278 cm -1 Raman intensity at and standard curve.

[0023] Figure 3 It is the specific experimental result in the test example of the present invention.

[0024] Figure 4 It is the specific experimental result in the test example of the present invention. DETAILED DESCRIPTION

[0025] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0026] Embodiment 1

[0027] 1. Preparation of Au-Ag@MnO2 nanomaterials:

[0028] First, Au NPs were synthesized by citrate reduction method. 0.8 mL 1% (w / v) HAuCl4·4H2O solution was added to 80 mL ultrapure water and heated to boiling. 0.8 mL 1% (w / v) sodium citrate solution was quickly added and kept boiling for 10 min. The solution was redispersed in 40 mL of water by centrifugation. 4 mL of Au NPs were dissolved in 36 mL ultrapure water, 0.8 mL 1 mM MBIA was added, and after incubation at 50 °C for 1 h, 2.4 mL 10 mM hydroquinone and 2.8 mL 1 mM silver nitrate were added in sequence and allowed to stand for 1 h. Au-Ag Janus NPs were redispersed in 4 mL of water by centrifugation. After the Au-Ag Janus NPs solution was mixed with KMnO4 (1.7 mg), 0.2 mL 1% (w / v) polyacrylic acid was added dropwise to the above solution and stirred for another 30 min. The color changes from purple to yellow and finally to black. Wash the nanomaterial several times with pure water. Finally, dissolve the nanomaterial in 1 mL of pure water.

[0029] 2. Establishment of H2O2 Raman analysis method

[0030] The Au-Ag@MnO2 nanomaterials were mixed with H2O2 solutions of different concentrations (0.01nM, 0.05nM, 0.1nM, 0.5nM, 1nM, 5nM, 10nM, 50nM, 100nM), centrifuged after 30min, and washed with 70% ethanol aqueous solution. Raman spectrometry was performed at room temperature using 785nmAr + The Raman spectrum of the assembly was tested by an ion laser source, with the logarithm of H2O2 concentration as the horizontal axis and the peak at 1278 cm -1 The Raman intensity at is the standard curve on the ordinate.

[0031] Embodiment 2

[0032] 1. Preparation of Au-Ag@MnO2 nanomaterials:

[0033] AuNPs were synthesized by citrate reduction method. 0.9mL 1% (w / v) HAuCl4·4H2O solution was added to 90mL ultrapure water and heated to boiling. 0.9mL 1% (w / v) sodium citrate solution was quickly added and kept boiling for 15min. The solution was redispersed in 45mL water by centrifugation. 5mL AuNPs were dissolved in 45mL ultrapure water, 0.8mL 1mM MBIA was added, and after incubation at 60℃ for 2h, 3mL 10mM hydroquinone and 3.5mL 1mM silver nitrate were added in sequence and allowed to stand for 2h. Au-Ag Janus NPs were redispersed in 5mL water by centrifugation. After mixing the Au-Ag Janus NPs solution with KMnO4 (2.1mg), 0.25mL 1% (w / v) polyacrylic acid was added dropwise to the above solution and stirred for another 1h. The color changed from purple to yellow and finally to black. The nanomaterials were washed several times with pure water. Finally, the nanomaterials were dissolved in 1 mL of pure water. The characterization results of Au-Ag@MnO2 nanomaterials are shown in Figure 1 .

[0034] 2. Establishment of H2O2 Raman analysis method

[0035] The Au-Ag@MnO2 nanomaterials were mixed with H2O2 solutions of different concentrations (0.01nM, 0.05nM, 0.1nM, 0.5nM, 1nM, 5nM, 10nM, 50nM, 100nM), centrifuged after 30min, and washed with 70% ethanol aqueous solution. Raman spectrometry was performed at room temperature using 785nmAr + The Raman spectrum of the assembly was tested by an ion laser source, with the logarithm of H2O2 concentration as the horizontal axis and the peak at 1278 cm -1 The Raman intensity at the vertical axis is the standard curve. Figure 2 ,Depend on Figure 2 It can be seen that the logarithm of H2O2 concentration in this method is similar to that at 1278cm -1 There is a linear relationship between the Raman intensity at the position and the concentration of H2O2 in the sample.

[0036] Embodiment 3

[0037] 1. Preparation of Au-Ag@MnO2 nanomaterials:

[0038] AuNPs were synthesized by citrate reduction method. 1 mL of 1% (w / v) HAuCl4·4H2O solution was added to 100 mL of ultrapure water and heated to boiling. 1 mL of 1% (w / v) sodium citrate solution was quickly added and kept boiling for 20 min. The solution was redispersed in 50 mL of water by centrifugation. 6 mL of AuNPs were dissolved in 54 mL of ultrapure water, 1.2 mL of 1 mM MBIA was added, and after incubation at 70°C for 3 h, 3.6 mL of 10 mM hydroquinone and 4.2 mL of 1 mM silver nitrate were added in sequence and allowed to stand for 3 h. Au-Ag Janus NPs were redispersed in 6 mL of water by centrifugation. After mixing the Au-Ag Janus NPs solution with KMnO4 (2.5 mg), 0.3 mL of 1% (w / v) polyacrylic acid was added dropwise to the above solution and stirred for another 1.5 h. The color changed from purple to yellow and finally to black. The nanomaterials were washed several times with pure water. Finally, the nanomaterials were dissolved in 1 mL of pure water.

[0039] 2. Establishment of H2O2 Raman analysis method

[0040] The Au-Ag@MnO2 nanomaterials were mixed with H2O2 solutions of different concentrations (0.01nM, 0.05nM, 0.1nM, 0.5nM, 1nM, 5nM, 10nM, 50nM, 100nM), centrifuged after 30min, and washed with 70% ethanol aqueous solution. Raman spectrometry was performed at room temperature using 785nmAr + The Raman spectrum of the assembly was tested by an ion laser source, with the logarithm of H2O2 concentration as the horizontal axis and the peak at 1278 cm -1 The Raman intensity at is the standard curve on the ordinate.

[0041] Test Case

[0042] Specificity experiment: In order to further evaluate the selectivity of the constructed Raman sensor for detecting H2O2, Au-Ag@MnO2 nanomaterials were mixed with 1nM H2O2 solution and 10nM interference solution (phenylalanine (Phe), CuCl2, glucose (Glu), ascorbic acid (AA), glutathione (GSH) and cysteine ​​(Cys)), respectively, and centrifuged after 30 minutes to test its SERS performance. The results are shown in Figure 2. Figure 3 Similarly, the H2O2 solution with a concentration of 1μM and the interfering substance solution with a concentration of 10μM were measured, and the results are shown in Figure 4 .Depend on Figure 3 It can be seen that the sensor is highly selective for H2O2 at low concentrations (levels; Figure 4 It can be seen that except for AA, GSH and Cys, the sensor still has good selectivity for H2O2 in the presence of high concentrations of interferents.

[0043] Obviously, the above embodiments are merely examples for clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the protection scope of the invention.

Claims

1. A Raman detection method for hydrogen peroxide based on Au-Ag@manganese dioxide nanomaterials, characterized in that: The following steps are involved: S1, dissolving Au NPs in water, adding 2-mercaptobenzimidazole-5-carboxylic acid, incubating at 50-70 °C for 1-3 h, adding hydroquinone and a silver source, standing to obtain Au-Ag Janus NPs, and redispersing in water to obtain Au-Ag Janus NPs; S2, after mixing the Au-Ag Janus NPs solution in S1 with KMnO4, polyacrylic acid is added dropwise and mixed to obtain Au-Ag@MnO2 nanomaterials; S3, mixing the Au-Ag@MnO2 nanomaterial obtained in S2 with the H2O2 solution, separating the solid from the liquid to obtain the solid phase, detecting the Raman intensity of the solid phase, and realizing the qualitative or quantitative detection of H2O2; The concentration of the silver source described in S1 is 1-2 mM; The concentration of 2-mercaptobenzimidazole-5-carboxylic acid in S1 is 1-2 mM; The hydroquinone concentration described in S1 is 10-20 mM; The concentration of polyacrylic acid in S2 is 1%-2% w / v; The mass ratio of Au-Ag Janus NPs to KMnO4 in the Au-Ag Janus NPs solution described in S2 is 0.5:0.9~0.5:1; S3 also includes washing the solid phase with 70-80% ethanol in water.

2. The Raman detection method according to claim 1, characterized in that: The preparation method of the standard curve for quantitative detection in S3 is as follows: the Au-Ag@MnO2 nanomaterials are mixed with H2O2 solutions of different concentrations, the solid-liquid separation is performed to obtain the solid phase, and the Raman intensity of the solid phase is detected to obtain the Raman intensity of the solid phase with the logarithm of H2O2 concentration as the horizontal axis and the intensity of 1278 cm -1 The Raman intensity at the position is taken as the ordinate, and a standard curve for quantitative detection is obtained.

3. The Raman detection method according to claim 2, characterized in that: Using 785 nm Ar + The solid phase Raman intensity is detected by an ion laser source.

4. The Raman detection method according to claim 2, characterized in that: The concentrations of H2O2 solutions ranged from 0.01 to 100 nM.

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