Preparation method and application of carbon quantum dots with oxidation resistance and antibacterial property

Abstract

The invention discloses a preparation method and application of carbon quantum dots with both oxidation resistance and antibacterial property, and the preparation method comprises the following steps: weighing 0.2-0.6 g of disodium ethylene diamine tetraacetate and 0.1-0.8 g of polyethyleneimine, putting the weighed disodium ethylene diamine tetraacetate and polyethyleneimine into a beaker, adding 10-20ml of deionized water into the beaker, and sealing the mouth of the beaker; the preparation method comprises the following steps: adding a solvent, stirring, accelerating mixing by ultrasonic waves until solids are completely dissolved, then transferring into a polytetrafluoroethylene lining, reacting for 6 hours at 140-220 DEG C, and then naturally cooling. And filtering the orange brown solution with a 0.22 [mu] m filter head to remove unfinished reactants, and then dialyzing for two days with a 3500 Da dialysis bag. Compared with the prior art, the antibacterial material has good antibacterial performance and oxidation resistance, and can be used as an antibacterial drug, an antibacterial coating and an antibacterial solution to prepare antibacterial material products; the preparation method is simple, and production is easy to control; raw materials are easy to obtain, and preparation cost is low.

Description

Technical Field

[0001] The present invention relates to the technical field of a preparation method and application of carbon quantum dots, and particularly relates to a preparation method and application of carbon quantum dots with both antioxidant and antibacterial properties. Background Art

[0002] There are two difficulties in the treatment of infectious wounds. One is the failure to promptly remove bacteria; the other is the generation of reactive oxygen species at the infected site.

[0003] For bacteria, exudate and necrotic tissue can serve as good culture media to promote their continuous reproduction and accumulation. At the same time, they can also release harmful toxins, degradation substances, proteases, and other harmful substances, which can damage the surrounding normal tissues, hinder the movement and re-epithelialization of cells involved in wound healing, cause host immune system defects and prevent the attack on bacteria, increasing the risk of secondary infection, and thus affecting wound healing.

[0004] Secondly, in a normal organism, the generation of free radicals and the rate of free radical scavenging are in a dynamic balance. However, when the injured part of the body is infected by bacteria, the infected wound has a higher level of inflammation, such as higher levels of inflammatory factors and more inflammatory cells. In this process, infiltrating inflammatory cells such as neutrophils and macrophages will generate reactive oxygen species (ROS). Due to the excessive accumulation of ROS in the wound, it will not only trigger a severe inflammatory response but also affect the normal operation of endogenous stem cells and macrophages, thereby hindering tissue regeneration.

[0005] In addition to the ROS generated by the wound itself, the ROS caused by bacterial infection will also cause serious damage to endothelial cells, blood vessels, and endothelial cells, hindering the healing of chronic wounds.

[0006] This series of problems caused by microbial infection pose a major challenge to the clinical treatment of wound infection. Therefore, a comprehensive treatment strategy for bacterial-infected wounds is needed, and there is an urgent need for an antibacterial material that can simultaneously remove excessive ROS while antibacterial.

[0007] To solve the above problems, a series of improvements have been made. Summary of the Invention

[0008] The purpose of the present invention is to provide a preparation method and application of carbon quantum dots with both antioxidant and antibacterial properties to overcome the above-mentioned disadvantages and deficiencies of the prior art.

[0009] A preparation method of carbon quantum dots with both antioxidant and antibacterial properties includes the following steps:

[0010] Step 1: Weigh 0.2 - 0.6 g of disodium ethylenediaminetetraacetate and 0.1 g - 0.8 g of polyethyleneimine and put them into a beaker. Add 10 - 20 ml of deionized water to the beaker and seal the beaker mouth.

[0011] Step 2: Use ultrasound to accelerate the mixing until all the solids are dissolved, then transfer it to a polytetrafluoroethylene liner and react at 140 - 220 °C for 6 h and then cool naturally.

[0012] Step 3: Filter the orange - brownish - yellow solution with a 0.22 - μm filter head to remove the unreacted reactants, and then use a dialysis bag with a molecular weight cut - off of 3500 Da for dialysis for two days.

[0013] The application of a carbon quantum dot with both antioxidant and antibacterial properties, which is used in antibacterial drugs, antibacterial coatings, antibacterial solutions to prepare antibacterial material products.

[0014] The beneficial effects of the present invention:

[0015] Compared with the traditional technology, the present invention has good antibacterial and antioxidant properties, can be used as antibacterial drugs, antibacterial coatings, antibacterial solutions to prepare antibacterial material products; the preparation method of the present invention is simple, and the production is easy to control; the raw materials are easy to obtain and the preparation cost is relatively low. Description of the Drawings

[0016] Figure 1 It is the antibacterial effect diagrams of CDs with different concentrations against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Staphylococcus epidermidis.

[0017] Figure 2 It is the scavenging ability diagram of CDs with different concentrations against ABTS. Detailed Embodiments

[0018] The following further illustrates the present invention in conjunction with specific embodiments. It should be understood that the following embodiments are only used to illustrate the present invention and not to limit the scope of the present invention.

[0019] Figure 1 It is the antibacterial effect diagrams of CDs with different concentrations against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Staphylococcus epidermidis. Figure 2 It is the scavenging ability diagram of CDs with different concentrations against ABTS.

[0020] Example 1:

[0021] Weigh 0.557 g of disodium ethylenediaminetetraacetate and 0.135 g of polyethyleneimine and put them into a 50 mL beaker. Add 15 mL of deionized water to the beaker and seal the bottle mouth. Accelerate the mixing with ultrasound until all the solids are dissolved, then transfer it to a polytetrafluoroethylene liner and react at 180 °C for 6 hours and then cool naturally. Filter the orange-brownish-yellow solution with a 0.22 μm filter head to remove the unreacted reactants, and then use a dialysis bag with a molecular weight cut-off of 3500 Da for dialysis for two days. The brownish-yellow powder obtained by freeze-drying is the carbon quantum dots CDs with both antioxidant and antibacterial properties.

[0022] Example 2

[0023] Weigh 0.3 g of disodium ethylenediaminetetraacetate and 0.7 g of polyethyleneimine and put them into a 50 mL beaker. Add 10 mL of deionized water to the beaker and seal the bottle mouth. Accelerate the mixing with ultrasound until all the solids are dissolved, then transfer it to a polytetrafluoroethylene liner and react at 160 °C for 6 hours and then cool naturally. Filter the orange-brownish-yellow solution with a 0.22 μm filter head to remove the unreacted reactants, and then use a dialysis bag with a molecular weight cut-off of 3500 Da for dialysis for two days. The brownish-yellow powder obtained by freeze-drying is the carbon quantum dots CDs with both antioxidant and antibacterial properties.

[0024] As Figure 1 shown, in the above examples, the ultimate goal is to obtain carbon quantum dots CDs with both antioxidant and antibacterial properties. And the reason why CDs can have such an effect is that CDs can be adsorbed onto the cell walls of bacteria and fungi through diffusion and electrostatic interactions. This results in the isolation of bacteria, blocking the uptake of nutrients and interfering with their physiological metabolism. The CDs enriched on the bacterial cell membrane / wall can also penetrate the cell membrane and inhibit the formation of bacterial biofilms, leading to the leakage of cytoplasmic contents. The CDs that enter the cells can bind to DNA and RNA in bacteria and fungi, changing the structures of DNA and RNA and causing the separation of the DNA double helix. Finally, under the combined influence of multiple effects, bacterial apoptosis occurs, thus achieving the antibacterial effect. At the same time, due to the rich functional groups on the surface of CDs and their ability to generate reactive oxygen species through photodynamic action, they have unique advantages in combating drug-resistant bacteria and emerging viruses, etc.

[0025] As Figure 2As shown, with the increase in the concentration of CDs, the ability to scavenge ABTS also increases, and it is found that the antioxidant activity of CDs is concentration-dependent. When the concentration of CDs is 100 μg / mL, its ability to scavenge ABTS radicals is the strongest, about 98%. This proves that the ability of CDs to scavenge ABTS radicals increases with the increase in its concentration, indicating that CDs have concentration-dependent antioxidant activity. When the concentration of CDs reaches 100 μg / mL, its efficiency in scavenging ABTS radicals is the highest, about 98%. Therefore, the above experimental data prove that CDs are a new type of material with strong antioxidant ability.

[0026] In summary, the present invention has good antibacterial and antioxidant properties and can be used as antibacterial drugs, antibacterial coatings, antibacterial solutions to prepare antibacterial material products. The principle is that the present invention is achieved by synthesizing CDs, and subsequent theoretical and experimental data also prove that the CDs of the present invention have antibacterial and antioxidant properties. On the other hand, the preparation method of the present invention is simple and the production is easy to control; the raw materials disodium ethylenediaminetetraacetate and polyethyleneimine are easily available, and the preparation cost is relatively low.

[0027] The above has described the embodiments of the present invention in conjunction with the accompanying drawings. However, the present invention is not limited to the above embodiments and can also make various changes according to the purpose of the invention of the present invention. Any changes, modifications, substitutions, combinations or simplifications made based on the spirit and principle of the technical solution of the present invention shall be equivalent replacement methods. As long as they meet the invention purpose of the present invention and do not deviate from the technical principle and inventive concept of the present invention using disodium ethylenediaminetetraacetate and polyethyleneimine to prepare CDs and apply them to the antibacterial field, they all belong to the protection scope of the present invention.

Claims

1. A preparation method of carbon quantum dots with both antioxidant and antibacterial properties, characterized in that, It includes the following steps: Step 1: Weigh 0.2 - 0.6 g of disodium ethylenediaminetetraacetate and 0.1 g - 0.8 g of polyethyleneimine and put them into a beaker. Add 10 - 20 ml of deionized water to the beaker and seal the bottle mouth; Step 2: Use ultrasonic to accelerate the mixing until all the solids are dissolved, then transfer it to a polytetrafluoroethylene inner liner and react at 140 - 220 °C for 6 h and then cool naturally; Step 3: Filter the orange - brownish solution with a 0.22 μm filter head to remove the unreacted reactants, and then use a dialysis bag with a molecular weight cut - off of 3500 Da for dialysis for two days.

2. The application of the carbon quantum dots with both antioxidant and antibacterial properties according to claim 1, characterized in that: It is used for antibacterial drugs, antibacterial coatings, antibacterial solutions to prepare antibacterial material products.

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