Gold nanoparticle-gold nanocluster composite material as well as preparation method and application thereof

Abstract

The invention discloses a gold nanoparticle-gold nanocluster composite material as well as a preparation method and application thereof, and belongs to the technical field of nano materials. The composite material is prepared by the following steps of, S1, a HAuCl4 aqueous solution is mixed with a galactose oxidase (GO) solution to obtain a mixed solution; S2, the pH value of the mixed solution is adjusted to 11.0 to 12.0; and S3, the mixed solution with the adjusted pH is subjected to a reaction at the temperature of 35 DEG C to 40 DEG C, and the gold nanoparticle-gold nanocluster composite material is obtained. The invention further discloses application of the gold nanoparticle-gold nanocluster composite material in Ag < + > detection. The composite material can be used for directly detecting low-concentration Ag < + >.

Description

technical field

[0001] The invention relates to the technical field of nanomaterials, in particular to a gold nanoparticle-gold nanocluster composite material and its preparation method and application. Background technique

[0002] Ag + Very toxic to many bacteria, viruses, algae and fungi, Ag + Its antibacterial effect has been applied in cosmetics, wood, clinical materials and many other fields. However, Ag + As heavy metal ions, once the concentration is too high, it will bring harm to the environment and human health. The U.S. Environmental Protection Agency (EPA) sets an upper limit of 0.050 mg / L for silver ions in drinking water. Therefore, for Ag + Real-time monitoring and reliable analysis are of great significance for environmental protection and disease prevention. has been developed for the detection of Ag + The analytical methods include atomic absorption spectrometry, inductively coupled plasma mass spectrometry and electrochemical methods. These techni...

Examples

preparation example Construction

[0029] This specific embodiment provides a method for preparing a gold nanoparticle-gold nanocluster composite material, comprising the following steps:

[0030] S1, the HAuCl 4 Mix the aqueous solution with the galactose oxidase solution at 35-40°C for 2-5 minutes to obtain a mixed solution; the HAuCl 4 The concentration of the aqueous solution is 10-15mmol / L, and the concentration of the galactose oxidase solution is 1.5-25mg / mL;

[0031] S2. Adjust the pH value of the mixed solution to 11.0-12.0 through sodium hydroxide solution; the concentration of the sodium hydroxide solution is 1-2mmol / L;

[0032] S3. Reacting the solution obtained in step S2 at 35-40° C. to obtain the gold nanoparticle-gold nanocluster composite material.

[0033] This specific embodiment also includes a gold nanoparticle-gold nanocluster composite material prepared by the above preparation method.

[0034] This specific embodiment also includes the gold nanoparticle-gold nanocluster composite mate...

Embodiment 1

[0041] This embodiment proposes a gold nanoparticle-gold nanocluster composite material, which is prepared by the following steps:

[0042] S1, 1mL, 10mmol / L HAuCl 4 Mix the aqueous solution with 1mL, 25mg / mL galactose oxidase solution, and stir vigorously at 37°C for 2min to obtain a mixed solution;

[0043] S2, adding 1mmol / L NaOH solution to adjust the pH value of the mixed solution to 12.0;

[0044] S3. Reacting the solution obtained in step S2 in a water bath at 37° C. for 24 hours to obtain a purple-red gold nanoparticle-gold nanocluster composite material (GNP-GOs-GNCs) solution.

[0045] combine figure 1 , the formation mechanism of GNP-GOs-GNCs is: the chloroauric acid solution is mixed with the galactose oxidase (GO) solution, under vigorous stirring, the chloroauric acid enters the inner space of the galactose oxidase, and the Au 3+ It is captured. 43 cysteine ​​residues in GO stabilize Au through strong Au-S bonds 3+ , forming GO-Au 3+ Complex. The pH of the...

Embodiment 2

[0048] The difference between the gold nanoparticle-gold nanocluster composite material prepared in this example and Example 1 is that the concentration of the galactose oxidase solution is 1.5 mg / mL.

[0049] From image 3 It can be seen that the gold nanoparticles in the composite materials prepared by different concentrations of galactose oxidase are spherical particles with uniform shape and good dispersion, and the higher the concentration of galactose oxidase, the smaller the particle size of the synthesized gold nanoparticles. Furthermore, we found some extremely small particles ( image 3 b and image 3 The circled part of e), zooming in on these small particles, we observed that some of these small particles are scattered around the large nanoparticles, and some are even tightly adhered to the surface of the particles. We speculate that these extremely small particles may be gold nanoclusters (GNCs). and pass image 3 c and image 3 f confirmed that these small p...

technical field

[0001] The invention relates to the technical field of nanomaterials, in particular to a gold nanoparticle-gold nanocluster composite material and its preparation method and application. Background technique

[0002] Ag + Very toxic to many bacteria, viruses, algae and fungi, Ag + Its antibacterial effect has been applied in cosmetics, wood, clinical materials and many other fields. However, Ag + As heavy metal ions, once the concentration is too high, it will bring harm to the environment and human health. The U.S. Environmental Protection Agency (EPA) sets an upper limit of 0.050 mg / L for silver ions in drinking water. Therefore, for Ag + Real-time monitoring and reliable analysis are of great significance for environmental protection and disease prevention. has been developed for the detection of Ag + The analytical methods include atomic absorption spectrometry, inductively coupled plasma mass spectrometry and electrochemical methods. These techni...

Examples

preparation example Construction

[0029] This specific embodiment provides a method for preparing a gold nanoparticle-gold nanocluster composite material, comprising the following steps:

[0030] S1, the HAuCl 4 Mix the aqueous solution with the galactose oxidase solution at 35-40°C for 2-5 minutes to obtain a mixed solution; the HAuCl 4 The concentration of the aqueous solution is 10-15mmol / L, and the concentration of the galactose oxidase solution is 1.5-25mg / mL;

[0031] S2. Adjust the pH value of the mixed solution to 11.0-12.0 through sodium hydroxide solution; the concentration of the sodium hydroxide solution is 1-2mmol / L;

[0032] S3. Reacting the solution obtained in step S2 at 35-40° C. to obtain the gold nanoparticle-gold nanocluster composite material.

[0033] This specific embodiment also includes a gold nanoparticle-gold nanocluster composite material prepared by the above preparation method.

[0034] This specific embodiment also includes the gold nanoparticle-gold nanocluster composite mate...

Embodiment 1

[0041] This embodiment proposes a gold nanoparticle-gold nanocluster composite material, which is prepared by the following steps:

[0042] S1, 1mL, 10mmol / L HAuCl 4 Mix the aqueous solution with 1mL, 25mg / mL galactose oxidase solution, and stir vigorously at 37°C for 2min to obtain a mixed solution;

[0043] S2, adding 1mmol / L NaOH solution to adjust the pH value of the mixed solution to 12.0;

[0044] S3. Reacting the solution obtained in step S2 in a water bath at 37° C. for 24 hours to obtain a purple-red gold nanoparticle-gold nanocluster composite material (GNP-GOs-GNCs) solution.

[0045] combine figure 1 , the formation mechanism of GNP-GOs-GNCs is: the chloroauric acid solution is mixed with the galactose oxidase (GO) solution, under vigorous stirring, the chloroauric acid enters the inner space of the galactose oxidase, and the Au 3+ It is captured. 43 cysteine ​​residues in GO stabilize Au through strong Au-S bonds 3+ , forming GO-Au 3+ Complex. The pH of the...

Embodiment 2

[0048] The difference between the gold nanoparticle-gold nanocluster composite material prepared in this example and Example 1 is that the concentration of the galactose oxidase solution is 1.5 mg / mL.

[0049] From image 3 It can be seen that the gold nanoparticles in the composite materials prepared by different concentrations of galactose oxidase are spherical particles with uniform shape and good dispersion, and the higher the concentration of galactose oxidase, the smaller the particle size of the synthesized gold nanoparticles. Furthermore, we found some extremely small particles ( image 3 b and image 3 The circled part of e), zooming in on these small particles, we observed that some of these small particles are scattered around the large nanoparticles, and some are even tightly adhered to the surface of the particles. We speculate that these extremely small particles may be gold nanoclusters (GNCs). and pass image 3 c and image 3 f confirmed that these small p...

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