CN107855541A - A kind of method that silver nano-grain is prepared using pseudo-ginseng leaching liquor - Google Patents

Abstract

The invention provides a method for preparing silver nanoparticles by using the extract of Panax notoginseng, which comprises the following steps: (1) adding the slices of Panax notoginseng into deionized water and heating to boiling, and taking the supernatant after centrifugation to obtain the extract of Panax notoginseng (2) adding deionized water to the Radix Notoginseng extract to dilute; (3) adding an alkaline reagent to make the pH value of the Radix Notoginseng extract 7.2 to 9.1, and then heating it to boiling; (4) adding nitric acid The silver solution is added to the boiling panax notoginseng extract, and reacted in a boiling state; (5) after the reaction is completed, the obtained reaction solution is centrifuged, and the obtained precipitate is dried to obtain silver nanoparticles. The equipment adopted in the preparation method of the invention is simple and easy to operate. The notoginseng is convenient and easy to obtain, low in price and non-toxic, and the prepared silver nanoparticles can be applied in the field of biomedicine.

Description

A method for preparing silver nanoparticles by utilizing Panax notoginseng extract

technical field

The invention belongs to the technical field of preparation of nanometer materials, and in particular relates to a method for preparing silver nanoparticle by using a Panax notoginseng extract.

Background technique

Silver nanoparticles have many unique properties (optical, electrical and chemical, etc.), so they have a wide range of applications in many fields. For example, silver nanoparticles can be used as catalysts in industry to photocatalytically degrade organic pollutants; adding silver nanoparticles to chemical fiber products can increase the bactericidal function; silver nanoparticles can also enhance the Raman effect. The performance of silver nanoparticles depends largely on its preparation method, so the research on the preparation method of silver nanoparticles has gradually attracted attention.

There are many methods for the preparation of silver nanoparticles that have been reported, which can be generally divided into three categories: physical methods, chemical methods and biological methods. The equipment required by the physical method is expensive, and the uniformity of the generated particles is poor, so it is not suitable for large-scale industrial production. The chemical method is relatively simple to operate, and the size of the synthesized silver nanoparticles is small and uniform. It is mainly used in the fields of chemical industry, medicine and environment. However, chemical methods generally require the introduction of chemical reagents as reducing or dispersing agents, which may pose potential risks to the environment. Biological method has received great attention because of its green, safe and reliable synthesis process and low energy consumption. In recent years, methods of using various plant extracts to synthesize silver nanoparticles have emerged, such as the synthesis of silver nanoparticles through kiwi juice, watermelon juice, and orange juice. At present, although plant extracts can be used to synthesize silver nanoparticles, the number of available plants is small, and it is urgent to expand the types of available plants. At the same time, it is difficult to prepare highly dispersed and small-sized silver nanoparticles using plant extracts. It can be seen that finding new species to synthesize high-quality silver nanoparticles is an urgent problem to be solved in this field. Panax notoginseng is cheap and widely distributed in China, and the dried panax notoginseng can be stored for a long time. At present, there is no report on the preparation of silver nanoparticles with the Panax notoginseng extract. Based on the National Natural Science Foundation of China (11404210), the applicant further explored the preparation of silver nanoparticles from the Panax notoginseng extract.

Contents of the invention

The purpose of the present invention is to provide a green synthesis method for preparing silver nanoparticles by utilizing the Panax notoginseng extract. The invention has the advantages of simple preparation process, mild conditions, environmental friendliness and no chemical reagent residue, which lays a foundation for the application of silver nanoparticles in the field of biomedicine.

The method for preparing silver nanoparticles according to the present invention utilizing Panax notoginseng extract comprises the following steps:

(1) adding the Sanqi tablets into deionized water and heating to boiling, centrifuging and taking the supernatant to obtain the Radix Notoginseng extract;

(2) add deionized water to dilute in Radix Notoginseng extract;

(3) adding an alkaline reagent to make the pH value of the Panax notoginseng extract solution 7.2 to 9.1, and then heating it to boiling;

(4) Silver nitrate solution is added in the boiling Radix Notoginseng leaching solution, and react under boiling state;

(5) After the reaction is completed, the obtained reaction solution is centrifuged, and the obtained precipitate is dried to obtain silver nanoparticles.

The alkaline reagent in the step (3) is sodium hydroxide solution but not limited to sodium hydroxide; the concentration of the sodium hydroxide solution is 1mol/L, and the solvent is deionized water.

The concentration of the silver nitrate solution in the step (4) is 0.01mol/L, the volume is 0.5-3mL, and the solvent is deionized water.

The reaction time in the step (4) is 1 to 5 minutes.

In the step (3), the notoginseng extract is heated to boiling, and then kept boiling for 10 minutes.

The inventor also unexpectedly found in a large number of experiments: by controlling the ratio of sodium hydroxide solution and Panax notoginseng leaching solution to keep the pH value of the reaction system between 7.5 and 9.1, the average particle diameter of the prepared silver nanoparticles below 10 nanometers.

The preparation method of silver nanoparticles provided by the invention adopts simple equipment and convenient operation. Panax notoginseng extract is convenient and easy to get, cheap, and nontoxic, and replaces the chemical reagents (thiol, ascorbic acid, unsaturated alcohol, hydrazine, etc.) used in the past as a reducing agent with it, and the surface of the prepared silver nanoparticles will not Toxic chemical reagent residues are generated, and obvious optical signals are shown, so the synthesized nano-silver can be applied in the field of biomedicine.

Description of drawings

Fig. 1 is the photograph of the reaction solution obtained after reacting for 1 minute, 2 minutes, 3 minutes, 4 minutes and 5 minutes in Example 1.

Fig. 2 is that in embodiment 1, react 1 minute, 2 minutes, 3 minutes, 4 minutes, measure its ultraviolet-visible absorption spectrum (UV-Vis) figure after obtaining sample centrifugation after 5 minutes;

Fig. 3 is the transmission electron micrograph of the silver nanometer obtained when the reaction time is 5 minutes among the embodiment 1;

Fig. 4 is the X-ray diffraction spectrogram of the silver nanometer obtained when the reaction times is 5 minutes among the embodiment 1;

Fig. 5 is the photo of the reaction solution obtained after reacting for 1 minute, 2 minutes, 3 minutes, 4 minutes and 5 minutes in Example 2.

Fig. 6 is the ultraviolet-visible absorption spectrum (UV-Vis) figure that measures after obtaining sample centrifugation in embodiment 2 after 1 minute, 2 minutes, 3 minutes, 4 minutes, 5 minutes;

Fig. 7 is the transmission electron micrograph of the silver nanometer obtained when the reaction time is 5 minutes among the embodiment 2;

Fig. 8 is the energy spectrogram (EDX) of the silver nanometer obtained when the reaction time is 5 minutes among the embodiment 2;

Fig. 9 is the photo of the reaction solution obtained after reacting for 1 minute, 2 minutes, 3 minutes, 4 minutes and 5 minutes in Example 3;

Fig. 10 is the ultraviolet-visible absorption spectrum (UV-Vis) figure that measures after obtaining sample centrifugation in embodiment 3 after 1 minute, 2 minutes, 3 minutes, 4 minutes, 5 minutes;

Fig. 11 is the photo of the reaction solution obtained after reacting for 1 minute, 2 minutes, 3 minutes, 4 minutes and 5 minutes in Example 4;

Fig. 12 is the ultraviolet-visible absorption spectrum (UV-Vis) figure that obtains sample after centrifugation and measures after reaction 1 minute, 2 minutes, 3 minutes, 4 minutes, 5 minutes in embodiment 4;

Fig. 13 is the photo of the reaction solution obtained after reacting for 1 minute, 2 minutes, 3 minutes, 4 minutes and 5 minutes in Example 5;

Fig. 14 is the ultraviolet-visible absorption spectrum (UV-Vis) figure that obtains sample after centrifugation and measures after reaction 1 minute, 2 minutes, 3 minutes, 4 minutes, 5 minutes in embodiment 5;

Detailed ways

The present invention will be further described below in conjunction with the embodiments and accompanying drawings. Those skilled in the art should understand that the embodiments and accompanying drawings are only for better understanding of the present invention, and are not used to make any limitation.

The preparation process of the notoginseng extract used in the following examples is as follows: add 1 g of notoginseng into 80 mL of deionized water and heat to boiling, after centrifugation, take the notoginseng extract of the supernatant;

The silver nitrate solution preparation process is as follows: 0.085g silver nitrate crystals are dissolved in 50mL deionized water to form a 0.01mol/L silver nitrate solution;

The preparation process of the sodium hydroxide solution is as follows: 2 g of sodium hydroxide crystals are dissolved in 50 mL of deionized water to form a 1 mol/L sodium hydroxide solution.

Embodiment one

(1) Wash the glass container used, and then rinse it with deionized water;

(2) Put 10 mL of Panax notoginseng leaching liquid aqueous solution into a flask, add 15 mL of deionized water to dilute, then add 100 μL of sodium hydroxide aqueous solution, test that the pH value is 7.5, then heat to boiling, and boil for 10 minutes;

(3) Add the 0.01mol/L silver nitrate solution of 0.5mL in the flask, react under boiling conditions for 1 minute, 2 minutes, 3 minutes, 4 minutes, and take samples after 5 minutes. The sample photo is as shown in Figure 1;

(4) The samples obtained after the above different reaction times were centrifuged at 8000 rpm for 10 minutes, and the resulting precipitate was dried at 40-50° C. for 10 minutes to obtain silver nanoparticles.

Fig. 2 measures its ultraviolet-visible absorption spectrum (UV-Vis) after centrifuging the sample gained from the above reaction for 1 minute, 2 minutes, 3 minutes, 4 minutes, and 5 minutes by using a UV-2600 ultraviolet spectrophotometer of Shimadzu Corporation in Japan picture. The absorption peaks produced by silver nanometers are all around 420nm, and produce obvious plasmon resonance signals, which can be used for further biological applications.

FIG. 3 is a TEM image of silver nanometers obtained from the above reaction for 5 minutes using JEM-2100F field emission transmission electron microscope of JEOL Ltd. It can be clearly seen that the obtained silver nanoparticles present a spherical shape. The morphology of the samples obtained in the remaining 1 minute, 2 minutes, 3 minutes and 4 minutes is similar to that of the silver nanoparticles obtained in 5 minutes, with an average diameter of about 8 nm.

Fig. 4 is the spectrogram that adopts the D/max-2600PC type X-ray diffractometer of Japan Co., Ltd. to characterize the silver nanoparticles obtained from the above reaction for 5 minutes, which is very consistent with the standard spectrum of silver, further illustrating that the reaction synthesized silver nanoparticles.

Embodiment two

(1) Wash the glass container used, and then rinse it with deionized water;

(2) Put 10 mL of Panax notoginseng extract solution into a flask, add 15 mL of deionized water to dilute, then add 100 μL of sodium hydroxide aqueous solution, test the pH value to 7.6, then heat to boiling, and boil for 10 minutes;

(3) Add 1 mL of 0.01 mol/L silver nitrate solution in the flask, react under boiling conditions for 1 minute, 2 minutes, 3 minutes, 4 minutes, 5 minutes and then take samples. The photo of the sample is shown in Figure 5;

(4) The samples obtained after the above different reaction times were centrifuged at 8000 rpm for 10 minutes, and the resulting precipitate was dried at 40-50° C. for 10 minutes to obtain silver nanoparticles.

Fig. 6 adopts the UV-2600 type ultraviolet spectrophotometer of Shimadzu Corporation of Japan to measure its ultraviolet-visible absorption spectrum (UV-Vis) figure after centrifuging the sample gained from the above reaction for 1 minute, 2 minutes, 3 minutes, 4 minutes and 5 minutes . The absorption peaks produced by silver nanoparticles are all around 425nm, which produces obvious plasmon resonance signals.

Fig. 7 is a JEM-2100F field emission transmission electron microscope of Japan Electronics Co., Ltd. to characterize the silver nanoparticles obtained from the above reaction for 5 minutes. It can be clearly seen that the obtained silver nanoparticles present a spherical shape. The morphology of the samples prepared in the remaining 1 minute, 2 minutes, 3 minutes, and 4 minutes is similar to that of silver nanometers in 5 minutes, and the average diameter is about 9 nm.

Figure 8 is the EDX spectrum of the silver nanoparticles obtained from the above reaction for 5 minutes using the EDAX Falcon s60 energy spectrometer of Japan Electronics Corporation. It can be clearly seen that the composition of the nanoparticles obtained from the reaction is silver. Cu is a component of the copper mesh used in the test and is not an impurity contained in the nanoparticles.

Embodiment three

(1) Wash the glass container used, and then rinse it with deionized water;

(2) Put 10 mL of Panax notoginseng extract solution into a flask, add 15 mL of deionized water to dilute, then add 50 μL of sodium hydroxide aqueous solution, test the pH value to 7.2, then heat to boiling, and boil for 10 minutes;

(3) Add 1 mL of 0.01 mol/L silver nitrate solution in the flask, react under boiling conditions for 1 minute, 2 minutes, 3 minutes, 4 minutes, and take samples after 5 minutes. The photo of the sample is shown in Figure 9;

(4) The samples obtained after the above different reaction times were centrifuged at 8000 rpm for 10 minutes, and the resulting precipitate was dried at 40-50° C. for 10 minutes to obtain silver nanoparticles.

Fig. 10 measures its ultraviolet-visible absorption spectrum (UV-Vis) after the centrifugation of the sample gained from the above-mentioned reaction for 1 minute, 2 minutes, 3 minutes, 4 minutes and 5 minutes by using a UV-2600 ultraviolet spectrophotometer of Shimadzu Corporation in Japan picture. The absorption peaks produced by silver nanometers are all around 414nm, and produce obvious plasmon resonance signals, which can be used for further biological applications.

In addition, the morphology of the transmission electron microscope (TEM) of silver nanometers is similar to Figure 3 and Figure 7, the X-ray diffraction spectrum (XRD) is similar to Figure 4, and the energy spectrum (EDX) is similar to Figure 8 , which will not be repeated here.

Embodiment Four

(1) Wash the glass container used, and then rinse it with deionized water;

(2) Put 20 mL of Panax notoginseng extract solution into a flask, add 5 mL of deionized water to dilute, then add 200 μL of sodium hydroxide aqueous solution, test the pH value to 9.1, then heat to boiling, and boil for 10 minutes;

(3) Add 1mL of 0.01mol/L silver nitrate solution in the flask, react under boiling conditions for 1 minute, 2 minutes, 3 minutes, 4 minutes, 5 minutes and then take samples. The photo of the sample is shown in Figure 11;

(4) The samples obtained after the above different reaction times were centrifuged at 8000 rpm for 10 minutes, and the resulting precipitate was dried at 40-50° C. for 10 minutes to obtain silver nanoparticles.

Fig. 12 measures its ultraviolet-visible absorption spectrum (UV-Vis) after adopting the UV-2600 type ultraviolet spectrophotometer of Shimadzu Corporation of Japan to the above-mentioned reaction 1 minute, 2 minutes, 3 minutes, 4 minutes, 5 minutes gained sample centrifugation picture. The absorption peaks produced by silver nanometers are all around 410nm, and produce obvious plasmon resonance signals, which can be used for further biological applications.

In addition, the morphology of the transmission electron microscope (TEM) of silver nanometers is similar to Figure 3 and Figure 7, the X-ray diffraction spectrum (XRD) is similar to Figure 4, and the energy spectrum (EDX) is similar to Figure 8 , which will not be repeated here.

Embodiment five

(1) Wash the glass container used, and then rinse it with deionized water;

(2) Put 10 mL of Panax notoginseng extract solution into a flask, add 15 mL of deionized water to dilute, then add 100 μL of sodium hydroxide aqueous solution, test the pH value to 7.6, then heat to boiling, and boil for 10 minutes;

(3) Add 3mL of 0.01mol/L silver nitrate solution in the flask, react under boiling conditions for 1 minute, 2 minutes, 3 minutes, 4 minutes, 5 minutes and then take samples. The photo of the sample is shown in Figure 13;

(4) The samples obtained after the above different reaction times were centrifuged at 8000 rpm for 10 minutes, and the resulting precipitate was dried at 40-50° C. for 10 minutes to obtain silver nanoparticles.

Fig. 14 adopts the UV-2600 type ultraviolet spectrophotometer of Shimadzu Corporation of Japan to measure its ultraviolet-visible absorption spectrum (UV-Vis) after the centrifugation of the sample gained from the above reaction for 1 minute, 2 minutes, 3 minutes, 4 minutes and 5 minutes picture. The absorption peaks produced by silver nanometers are all around 407nm, and produce obvious plasmon resonance signals, which can be used for further biological applications.

In addition, the morphology of the transmission electron microscope (TEM) of silver nanometers is similar to Figure 3 and Figure 7, the X-ray diffraction spectrum (XRD) is similar to Figure 4, and the energy spectrum (EDX) is similar to Figure 8 , which will not be repeated here.

Although the above-mentioned examples only cite laboratory-scale reactions, those skilled in the art should understand that the method of the present invention is also applicable to industrial-scale reactions.

Claims (6)

1. a method utilizing Radix Notoginseng extract to prepare silver nanoparticles, comprising the steps: (1) adding the Sanqi tablets into deionized water and heating to boiling, centrifuging and taking the supernatant to obtain the Radix Notoginseng extract; (2) add deionized water to dilute in Radix Notoginseng extract; (3) adding an alkaline reagent to make the pH value of the Panax notoginseng extract solution 7.2 to 9.1, and then heating it to boiling; (4) Silver nitrate solution is added in the boiling Radix Notoginseng leaching solution, and react under boiling state; (5) After the reaction is completed, the obtained reaction solution is centrifuged, and the obtained precipitate is dried to obtain silver nanoparticles. 2. method according to claim 1, is characterized in that, in described step (3), alkaline reagent is sodium hydroxide solution. 3. method according to claim 2, is characterized in that, the concentration of described sodium hydroxide solution is 1mol/L, and solvent is deionized water. 4. method according to claim 1, is characterized in that, the concentration of silver nitrate solution is 0.01mol/L in the described step (4), and volume is 0.5～3mL, and solvent is deionized water. 5. The method according to claim 1, characterized in that the reaction time in the step (4) is 1 to 5 minutes. 6. The method according to claim 1, characterized in that, in the step (3), after heating the notoginseng extract to boiling, keep boiling for 10 minutes.