TW201513953A - Preparation method for water solution containing metal nano-particles - Google Patents

Abstract

The invention provides a preparation method for water solution containing metal nano-particles comprising steps: firstly sputtering to form metal nano-particles composed of metal on a flexible substrate to prepare a sampling substrate, wherein the pressure of sputtering is greater than 4 mtorr, next placing the sampling substrate in a pure water solution, utilizing centrifugation to remove the metal nano-particles on the flexible substrate from the flexible substrate and into the pure water solution, thereby obtaining the water solution containing the metal nano-particles. The manufacturing method is simple with simple materials and can be applied to industries of medicine, medical instruments, skin care, foodstuff and textiles.

Description

Preparation method of aqueous solution containing metal nanoparticles

The invention relates to a preparation method of a solution containing metal particles, in particular to a preparation method of an aqueous solution containing metal nanoparticles.

Many materials in the nanometer size, due to the rapid increase in specific surface area, so its physical properties, chemical properties and block materials will be different, and even turned into the opposite characteristics. For example, gold and gold are inert metals in bulk materials, and it is difficult to participate in chemical reactions. However, if gold is dispersed into micron or even nanometer grades, its properties are completely different from those of gold blocks, such as nano-gold at low temperature. The oxidation of carbon monoxide has excellent catalytic ability, while the unique absorbance of nanogold can be applied to the sensor; in addition, the gold nanoparticle is also a stable and anti-oxidation nano material with excellent biocompatibility. It is easily combined with human antibodies, enzymes or cytokines, and is therefore often used for medical testing and drug release.

In silver, metallic silver has a well-recognized antibacterial effect. In general, an antibiotic can kill about six different antibiotics, but silver kills more than 600 bacteria, and silver is not toxic. Wide range and long history, and the nano-silver treated by nanotechnology has a sharp increase in surface area, so the bactericidal power can be greatly improved. . In addition, because nano silver sterilization uses positively charged nano silver particles to contact negatively charged microbial cells, it breaks down the cell wall and cell membrane, denatures the microbial cell proteins until they die, and achieves the sterilization effect. Therefore, nanometer The antibacterial ingredients of silver do not have any consumption, and the antibacterial ability can be effective for a long time.

Although there are various methods for preparing the above-mentioned nano gold or nano silver particles, since most of them are chemical methods, most of the prepared nano gold or nano silver solutions contain organic solvents or added chemicals. Reagents, therefore, cannot be directly applied to the human body and require an extremely complicated purification process.

For example, in the preparation of a nanosilver solution, the preparation of colloidal silver is currently generally carried out by chemical reduction or electrolysis. The chemical reduction method is to reduce the silver ions to the metallic silver by a chemical solution of a salt solution of silver. Since the chemical reduction method cannot reduce the silver ions to the metallic silver by 100%, there is residual in the solution. Silver ions and salts, as well as toxic intermediates with incomplete chemical reactions. The electrolysis method uses silver as an electrode and is obtained by low-voltage electrolysis in distilled water. This method must ensure that the water does not contain other salts. The concentration of the silver solution is about 30 ppm or less, and the silver particle size is about 1 -10nm or so. In addition, since the silver solution prepared by the electrolysis method contains metallic silver and ionic silver, if silver is added, the silver solution will precipitate white silver chloride, and since the solution contains silver ions, it is not suitable for consumption. Also avoid mixing with other salt substances during application, otherwise it is easy to produce silver salt.

As can be seen from the above description, although nano gold or nano silver is excellent. Biological applicability, however, residual solvent, unreacted chemical residues, or residual metal ions during the preparation process may cause discomfort to the human body for long-term use, for example, when the silver solution contains unreacted Complete silver ions, if they enter the human body, silver ions and other substances will deposit in the body and skin. After the sun is irradiated by the sun, the black metal silver will be reduced, which will cause a chronic silver precipitation (Argyria). Similarly, if a colloidal silver substance containing silver ions or a silver salt is used for daily care products, it will be absorbed by the skin to cause silver precipitation. In other words, the key to good nano-silver or nano-gold materials is that the lower the ratio of metal ions to other metal compounds, the higher the ratio of pure metal particles, but even with the most advanced purification technology, It is difficult to remove the metal ions in the nano metal solution prepared by the chemical method, and this is also a major bottleneck in the biological application of nano silver or nano gold.

Therefore, the object of the present invention is to provide a preparation method capable of simply preparing an aqueous solution of a metal-containing nanoparticle, comprising: (a) sputtering on a soft substrate to form a metal nanoparticle composed of a metal. Having a sample substrate, wherein the sputtering pressure is greater than 4 mtorr; (b) placing the sample substrate in a solution containing pure water, and removing the metal particles on the soft substrate from the soft substrate by centrifugation To the solution, the metal nanoparticle-containing solution can be obtained.

Preferably, the method for preparing the aqueous solution of the metal-containing nanoparticles comprises the particle diameter of the metal nanoparticles of 5 nm to 100 nm.

Preferably, the method for preparing an aqueous solution of the metal-containing nano-particles, wherein the metal nanoparticles have a particle diameter of 5 nm to 50 nm.

Preferably, the method for preparing an aqueous solution of the metal-containing nano-particles, wherein the metal nanoparticles have a particle diameter of 10 nm to 30 nm.

Preferably, the method for preparing an aqueous solution of the metal-containing nano-particles, wherein the metal is selected from the group consisting of gold or silver.

Preferably, the method for preparing an aqueous solution of the metal-containing nano-particles, wherein the flexible substrate is selected from the group consisting of woven fabrics, non-woven fabrics, or paper.

Preferably, in the method for preparing the aqueous solution containing the metal nanoparticles, the sputtering power density of the step (a) is 0.6 to 0.8 W/cm ² , and the film thickness formed by sputtering is less than 100 nm.

Preferably, in the preparation method of the aqueous solution containing metal nanoparticles, the film thickness formed by the step (a) is less than 50 nm.

The effect of the invention is that the soft substrate is desorbed into the aqueous solution by means of sputtering and centrifugation in a manner of depositing on a soft substrate, and the method is simple and can be directly applied to medical grade without adding any chemical reagent. Nano gold / nano silver aqueous solution.

Other features and effects of the present invention will be clearly shown in the embodiments with reference to the drawings, wherein: FIG. 1 is an SEM image showing the nano silver particles sputtered on the soft substrate of the specific example 1; Fig. 2 is a TEM image showing the nano gold particles in the nano gold solution prepared in the specific example 2.

The preparation method of the aqueous solution containing metal nanoparticles of the present invention is used for preparing an aqueous solution containing metal nanoparticles, and in particular, the aqueous solution containing metal nanoparticles is used for biomedical purposes, for example, for biological disinfection or consumption. A solution of nano silver or an aqueous solution of nano gold. Since the aqueous solution of nano silver or the aqueous solution of nano gold is a wound that can be taken directly or directly in contact with the human body, the solution must contain almost no metal ions, metal compounds or other chemical agents, and must be pure water. It is customary to prepare nano silver or nano gold by chemical methods. Therefore, the reaction solution is a general organic solvent instead of water. In addition, in the finally obtained solution, in addition to the nanoparticles of nano gold or nano silver obtained by the reaction. In addition, metal ions, metal compounds, or other chemical reagents remain. Therefore, they cannot be directly used in medical applications. Even if they are used, they must undergo complicated purification steps before use. The present invention is directed to the preparation of a medical grade pure nano gold or nano silver solution. By using a sputtering method and a centrifugal method, a high-purity nano gold or nano silver aqueous solution can be obtained not only in a simple process but also without purification.

A preferred embodiment of the method for preparing an aqueous solution of a metal-containing nanoparticle of the present invention comprises the following two steps.

In the step (a), a plurality of metal nanoparticles composed of a metal are sputtered on a soft substrate by sputtering to obtain a sample substrate.

Specifically, in the step (a), the soft substrate is first formed in a sputtering chamber, and then the sputtering pressure is controlled under a pressure of more than 4 mtorr to be sputtered and controlled on the soft substrate. The thickness of the sputter is not more than 100 nm.

The flexible substrate is selected from the group consisting of woven fabrics, non-woven fabrics, papers, and polymer films. The metal may be selected from the group consisting of gold, silver, copper, iron, and the like, and the metal nanoparticles have a particle diameter of 5 nm to 100 nm. Preferably, the flexible substrate is selected from the group consisting of woven fabric, non-woven fabric or paper, the metal is selected from gold or silver, and the metal nanoparticles have a particle diameter of 5 nm to 50 nm, and more preferably, the metal nanoparticles are The particle size is between 5 nm and 20 nm.

Since the purpose of the foregoing step (a) is to allow the target metal to be sputtered, a majority of the metal nanoparticles can be formed on the soft substrate instead of forming a film; however, the sputtering power is too high, and the sputtering is performed. The soft substrate is destroyed during the process, and the sputtering rate is too fast, and the result of the sputtering is that a continuous metal film is formed instead of the metal nanoparticles. Therefore, in order to efficiently form the metal nanoparticles, the softness is not destroyed. Preferably, the sputtering pressure is controlled to be greater than 4 mtorr, the sputtering power is less than 500 W, and the sputtering power density is between 0.6 and 0.8 w/cm ² . In addition, when the film thickness formed by the sputtering is too thick, the originally dispersed metal nanoparticles are also connected to each other to form a continuous film. Therefore, preferably, the film thickness formed by sputtering is not more than 50 nm, and more preferably, sputtering is formed. The film thickness is not more than 20 nm.

Since the particle size of the metal nanoparticles is controlled by the parameters of the sputtering, such as the film thickness of the plating film and the sputtering pressure, the process conditions of the sputtering can be adjusted according to the actual required particle size. A sample substrate having metal nanoparticle deposition having different particle sizes is obtained.

In the step (b), the sampled substrate is placed in a pure aqueous solution, and the metal particles on the soft substrate are separated from the soft substrate into the pure aqueous solution by centrifugation to obtain the aqueous solution containing the metal nanoparticles.

Specifically, in the step (b), the sample substrate is immersed in a centrifuge bottle containing a pure aqueous solution, and the centrifuge bottle is placed in a centrifuge, and the original sample is deposited and attached to the sample substrate by centrifugation. The upper metal nanoparticles are desorbed by centrifugal force to enter the pure aqueous solution to obtain the aqueous solution containing the metal nanoparticles.

It is to be noted that the object of the present invention is to prepare an aqueous solution containing metal nanoparticles suitable for medical grades. Therefore, the pure aqueous solution is only water and does not contain other chemical additives. Preferably, the water of the aqueous solution is It is selected from RO reverse osmosis water, deionized water and the like. However, it should be noted that if the metal nanoparticle-containing solution is used for other purposes, the solution for soaking the soft substrate may be applied as needed, and may contain an organic solvent or add other chemical agents.

It is to be noted that the content of the metal nanoparticle in the metal nanoparticle solution is related to the rotation speed of the centrifuge and the amount of the sample substrate originally immersed in the solution, and the centrifugal rotation speed is high or the sampling base originally immersed in the water. If the material is more, the content of the metal nanoparticle in the aqueous solution obtained later is higher. On the contrary, if the centrifugal rotation speed is lower or the sample substrate which is originally immersed in the water is less, the content of the metal nanoparticle in the subsequent aqueous solution is Lower. In order to effectively remove the metal nanoparticles from the soft substrate, preferably, the centrifugal speed is controlled at 100 to 5000 rpm.

Next, the preparation method of the aqueous solution containing metal nanoparticles of the present invention will be described by way of the following specific examples.

Specific example 1

Preparation of nano silver solution

First, the non-woven fabric is placed in a sputtering chamber, and silver is sputtered on the non-woven fabric under the condition that the sputtering target is silver, the sputtering pressure is 4 mtorr, and the sputtering power density is 0.6-0.8 W/cm ² . The thickness of the sputter was controlled to be about 10 nm to prepare a sample substrate. Referring to FIG. 1, FIG. 1 is a SEM (scanning electron microscope) photograph of the sample substrate. It can be seen from FIG. 1 that the particle size of the nano silver particles deposited on the nonwoven fabric after sputtering is about 30~. 35nm.

Take 6.5 g of the sampled substrate, and soak it in a centrifuge bottle containing 100 g of pure aqueous solution for about 5 to 10 minutes. After the sampled substrate is completely wet, the centrifuge bottle can be centrifuged (rotation speed: 3000 rpm, centrifugation time: 5) Minutes), after centrifugation, filtration is carried out, and the non-woven fabric is removed to obtain a nano silver solution containing nano silver particles.

Next, the silver concentration in the nano silver solution was measured by a plasma coupling method. From the measurement results, the silver concentration in the nano silver solution was 1221 ppb.

Specific example 2

Preparation of nano gold solution

First, the non-woven fabric with a specification of 25 gram per square meter is placed in a sputtering chamber under the condition that the sputtering target is gold, the sputtering pressure is 4 mtorr, and the sputtering power density is 0.6-0.8 W/cm ² . A sample substrate was prepared by sputtering on the nonwoven fabric and controlling the thickness of the sputtering to be about 10 nm.

Taking the sampled substrate 30 centimeters by 30 centimeters, immersed in a centrifuge bottle containing 100 g of pure aqueous solution for about 5 to 10 minutes, and the centrifuged bottle is centrifuged after the sampled substrate is completely wetted (rotation speed: 3000 rpm, centrifugation time) : 5 minutes), after centrifugation, filter again, remove the non-woven fabric, you can A nanogold solution containing nano gold particles was obtained.

The gold particles of the nano gold aqueous solution were measured by a transmission electron microscope (TEM). The TEM photograph showed that the gold particle size of the nano gold aqueous solution was approximately 5 to 12 nm.

Next, the nano silver aqueous solution prepared in the specific one was subjected to an antibacterial test of Staphylococcus aureus ( ATCC 6538P ), and the antibacterial results are shown in Table 1.

Antibacterial test instructions

The S. aureus strain was streaked on a slant medium, cultured at 37 ° C for 24 hours, then 5 ml of physiological saline was added, and 1 ml of the slant medium was added to 9 ml of liquid broth, and the physiological salt was directly used. The water was diluted 10 times, and then 0.1 ml of the bacterial liquid was taken out to the 9 cm plate culture dish, and the appropriate amount of nutrient agar was added and mixed thoroughly, and then cooled to a solid state, and cultured in a 37 ° C incubator for 24 hours. Take out and calculate the amount of bacteria. Then, 1 ml of a 10 ppm aqueous solution of nano silver was separately added to a centrifuge tube containing Staphylococcus aureus 1.0×10 ⁵ CFU (colony-forming units), and the centrifuge tube was placed in a 37° C. incubator. After the hour, dilute with physiological saline for 10 times, then take 0.1 ml of the bacterial solution from the dilution to the 9 cm plate, add the appropriate amount of nutrient agar, mix well, cool to a solid state, and finally place the plate in a 37 After 24 hours of incubation in a °C incubator, the number of residual bacteria was counted. The sterilization rate can be obtained by dividing the number of residual bacteria by the amount of bacteria.

It can be seen from the results of the above Table 1 that the sterilization rate of the nano silver solution can be as high as 99.9%, indicating that the nano silver solution prepared by the present invention has the same antibacterial property as the nano silver prepared by other chemical methods.

In summary, the present invention utilizes sputtering and centrifugation to desorb the soft substrate into the aqueous solution in a manner of depositing on a soft substrate, which is different from the general chemical synthesis or electrochemical synthesis of nano technology, and is used in the whole process. Chemical solvent, so there is no industrial pollution such as waste water and exhaust gas, and it can completely avoid the contamination during processing. Moreover, because it has the characteristics of simple preparation method and simple material processing, it can be widely used in medicines and medical materials. In the industry of skin care products, food, textiles, etc., it is indeed possible to achieve the object of the present invention.

The above is only the preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, that is, the simple equivalent changes and modifications made by the patent application scope and patent specification content of the present invention, All remain within the scope of the invention patent.

Claims (8)

A method for preparing an aqueous solution containing a metal nanoparticle, comprising: (a) sputtering a metal nanoparticle on a soft substrate to form a sample substrate, wherein the sputtering pressure is greater than 4 mtorr; (b) placing the sampled substrate in a pure aqueous solution, and removing the metal nanoparticle on the soft substrate from the soft substrate by centrifugation, and obtaining the metal nanoparticle solution in the pure aqueous solution. The method for producing a metal nanoparticle aqueous solution according to claim 1, wherein the metal nanoparticle has a particle diameter of 5 nm to 100 nm. The method for producing an aqueous solution containing a metal nanoparticle according to claim 2, wherein the metal nanoparticles have a particle diameter of 5 nm to 50 nm. The method for producing an aqueous solution containing a metal nanoparticle according to claim 3, wherein the metal nanoparticles have a particle diameter of 5 nm to 20 nm. The method for producing an aqueous solution containing a metal nanoparticle according to claim 1, wherein the metal is selected from gold or silver. The method for producing an aqueous solution containing a metal nanoparticle according to claim 1, wherein the soft substrate is selected from the group consisting of woven fabric, non-woven fabric, or paper. The method for producing an aqueous solution containing a metal nanoparticle according to claim 1, wherein the sputtering power density of the step (a) is from 0.6 to 0.8 W/cm ² and the film thickness formed by sputtering is less than 100 nm. The method for producing an aqueous solution containing a metal nanoparticle according to claim 7, wherein the film thickness formed by the sputtering is less than 50 nm.