Preparation method of plant-derived carbon quantum dots with anti-inflammatory imaging function

Abstract

The invention discloses a preparation method of plant-derived carbon quantum dots with an anti-inflammatory imaging function, which comprises the following steps: selecting various anti-inflammatory plant raw materials such as isatis tinctoria leaves, pea leaves, broad bean leaves, alfalfa leaves, cornflower, honeysuckle, rheum officinale, selfheal, dandelion leaves, corn poppy, semen trichosanthis, wormwood and magnolia petals, and preparing the plant-derived carbon quantum dots with the anti-inflammatory imaging function through a hydrothermal method and a microwave method. The preparation method comprises the following steps: taking a plurality of plant raw materials with the anti-inflammatory effect as a carbon source, respectively adopting a raw material pretreatment method of homogenization and solvent extraction, and taking a hydrothermal method or a microwave method as a carbonization mode to prepare the plant-derived carbon quantum dots with the anti-inflammatory effect. The carbon quantum dot prepared by the method has the characteristics of small size, high fluorescence quantum yield, good anti-inflammatory and biocompatibility and the like, can be used as a carrier of anti-inflammatory drugs or anti-inflammatory nano-drugs, and has a good development prospect in the field of biological medicines.

Description

Technical Field

[0001] The present invention belongs to the technical field of biopharmaceuticals, and in particular relates to a method for preparing plant-derived carbon quantum dots with anti-inflammatory imaging function. Background Art

[0002] Carbon quantum dots are a new type of carbon material with many advantages, including adjustable particle size, good photostability, easy functional modification, low toxicity, excellent biocompatibility and high water solubility, and a wide range of raw material sources. In addition, carbon quantum dots also have unique physicochemical properties and antibacterial activity. Carbon quantum dots prepared by heating natural carbon sources can inherit similar characteristics of their source carbon sources, making natural plants rich in anti-inflammatory components one of the ideal sources for synthesizing anti-inflammatory carbon quantum dots. In addition, in large-scale clinical applications, carbon quantum dots are more attractive due to the lower induction of bacterial resistance mechanisms.

[0003] The preparation methods of carbon quantum dots mainly include top-down methods, such as arc discharge, laser ablation, electrochemical and chemical oxidation, and bottom-up methods, such as template method, microwave method and hydrothermal method. Among them, microwave method and hydrothermal method have become commonly used methods for preparing carbon quantum dots due to their high power and high yield. At present, most of the research on the preparation of carbon quantum dots by hydrothermal and microwave methods is to use the raw materials directly after homogenization, resulting in low utilization of carbon sources and effective anti-inflammatory components. However, the anti-inflammatory components in the carbon source can be effectively extracted by solvent extraction, and the combination of hydrothermal and microwave methods can efficiently prepare plant-derived carbon quantum dots with anti-inflammatory effects. Summary of the invention

[0004] Based on the existing technology, this study aims to develop a method for preparing plant-derived carbon quantum dots. By adopting the strategy of natural raw material homogenization and plant powder solvent extraction, the anti-inflammatory active ingredients in natural carbon sources are effectively extracted, and plant-derived carbon quantum dots with anti-inflammatory properties are synthesized by hydrothermal and microwave methods. The obtained carbon quantum dots have high fluorescence quantum yield and show significant anti-inflammatory effects. They can be used as drug carriers or anti-inflammatory drugs in the biomedical field for the treatment of inflammation, and show broad development prospects.

[0005] In order to achieve these purposes and advantages, the present invention provides a method for preparing plant-derived carbon quantum dots with anti-inflammatory imaging function, comprising the following steps:

[0006] Step 1: Wash various plant raw materials with anti-inflammatory effects such as woad leaves, pea leaves, broad bean leaves, alfalfa leaves, cornflowers, honeysuckle, rhubarb, selfheal, dandelion leaves, poppy, trichosanthes seeds, mugwort, magnolia petals, etc., homogenize them with a high-speed homogenizer for a certain period of time, then centrifuge the mixture to remove residues and retain the supernatant.

[0007] Step 2: Vacuum freeze-dry various plants with anti-inflammatory effects to homogenize them into powders. Then mix them with extraction solvents (ultrapure water, 50% ethylene glycol aqueous solution and ethylene glycol) respectively, heat them in a water bath, and then vacuum filter them to collect the filtrate.

[0008] Step 3: The supernatant and filtrate in step 1 and step 2 are transferred to a stainless steel autoclave lined with polytetrafluoroethylene, respectively, and reacted at high temperature for a period of time. After cooling to room temperature, the large particles in the solution are removed by centrifugation and filtration, and finally a series of plant-derived carbon quantum dots with anti-inflammatory effects are obtained by dialysis and vacuum freeze drying.

[0009] Step 4: The supernatant and filtrate in step 1 and step 2 are transferred to a microwave synthesizer for high temperature reaction. After treatment, the supernatant and filtrate are cooled to room temperature, and large particles in the solution are removed by centrifugation and filtration. The reaction solution is then dialyzed and vacuum freeze-dried to finally obtain a series of plant-derived carbon quantum dots with anti-inflammatory effects.

[0010] Preferably, the high-speed homogenization time is 5-1000 min, and the centrifugal speed is 1000-10000 rpm / min;

[0011] Preferably, the water bath temperature is 50-80°C and the reaction time is 1-50h.

[0012] Preferably, the hydrothermal reaction temperature is 120-250°C, the time is 2-48h, and the centrifugal speed is 1000-90000rpm / min

[0013] Preferably, the microwave treatment temperature is 120-200°C, the time is 10-60 min, and the centrifugal speed is 1000-90000 rpm / min.

[0014] The present invention includes at least the following beneficial results:

[0015] (1) The present invention uses natural plants with anti-inflammatory effects as raw materials to prepare plant-derived carbon quantum dots, which has low cost and a wide range of material sources, providing ideas for the preparation of anti-inflammatory carbon quantum dots;

[0016] (2) The plant-derived carbon quantum dots prepared by the present invention have anti-inflammatory effects and can be used as carriers of anti-inflammatory drugs or anti-inflammatory nanomedicines, providing ideas for the development of biomedicine;

[0017] (3) The present invention has a simple preparation process and is easy to operate. The raw materials used and the materials required in the preparation process are all environmentally friendly, non-toxic, harmless and degradable. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is the fluorescence image of the diluted solution (100 times) of carbon quantum dots derived from broad bean leaves, alfalfa leaves, woad leaves and woad pollen under 365nm ultraviolet light; DETAILED DESCRIPTION

[0019] Embodiment 1:

[0020] Step 1: Wash various plant raw materials with anti-inflammatory effects such as woad leaves, broad bean leaves, alfalfa leaves, woad pollen, etc., homogenize them with a high-speed homogenizer for 10 minutes, then centrifuge the mixture to remove residues and retain the supernatant.

[0021] Step 2: The supernatant was transferred to a stainless steel autoclave lined with polytetrafluoroethylene, and the hydrothermal reaction temperature was 120°C for 20 hours. After cooling to room temperature, the solution was centrifuged and filtered to remove large particles, and finally a series of plant-derived carbon quantum dots with anti-inflammatory effects were obtained by dialysis and vacuum freeze drying. The fluorescence of the carbon quantum dot dilution prepared in Example 1 under 365nm ultraviolet light was as follows: Figure 1 shown.

[0022] Embodiment 2:

[0023] Step 1: Wash various plant materials with anti-inflammatory effects such as dandelion leaves, poppy, Trichosanthes seeds, and wormwood, vacuum freeze-dry, and homogenize into powder. Mix the plant powder with the extraction solvent (50% ethylene glycol aqueous solution), heat in a water bath at 80°C for 1 hour, and then vacuum filter and retain the filtrate.

[0024] Step 2: The filtrate was transferred to a microwave synthesizer, and the microwave reaction temperature was 250°C for 2 hours. After cooling to room temperature, large particles in the solution were removed by centrifugation and filtration, and the reaction solution was dialyzed and vacuum freeze-dried to finally obtain a series of plant-derived carbon quantum dots with anti-inflammatory effects.

[0025] Embodiment 3:

[0026] Step 1: Wash the woad leaves, homogenize them with a high-speed homogenizer for 1000 minutes, and then centrifuge the mixture to remove the residue and retain the supernatant.

[0027] Step 2: The supernatant was transferred to a stainless steel autoclave lined with polytetrafluoroethylene, and the hydrothermal reaction temperature was 200°C for 10 hours. After cooling to room temperature, large particles in the solution were removed by centrifugation and filtration, and plant-derived carbon quantum dots with anti-inflammatory effects were obtained by dialysis and vacuum freeze drying.

[0028] Embodiment 4:

[0029] Step 1: Wash the raw material of mugwort with anti-inflammatory effect, vacuum freeze-dry it, and homogenize it into powder. Mix the plant powder with extraction solvent (ultrapure water, 50% ethylene glycol aqueous solution and ethylene glycol) respectively, heat it in a water bath at 60°C for 1 hour, and then vacuum filter it to keep the filtrate.

[0030] Step 2: The filtrate was transferred to a microwave synthesizer, and the microwave reaction temperature was 200°C for 20 minutes. After cooling to room temperature, large particles in the solution were removed by centrifugation and filtration, and then the reaction solution was dialyzed and vacuum freeze-dried to finally obtain plant-derived carbon quantum dots with anti-inflammatory effects.

[0031] Embodiment 5:

[0032] Step 1: Wash various plant raw materials with anti-inflammatory effects, such as woad leaves, pea leaves, broad bean leaves, alfalfa leaves, cornflowers, honeysuckle, rhubarb, selfheal, dandelion leaves, poppy, trichosanthes seeds, mugwort, and magnolia petals, homogenize them with a high-speed homogenizer for 100 minutes, then centrifuge the mixture to remove residues and retain the supernatant.

[0033] Step 2: The supernatant was transferred to a stainless steel autoclave lined with polytetrafluoroethylene, and the hydrothermal reaction temperature was 180°C for 12 hours. After cooling to room temperature, large particles in the solution were removed by centrifugation and filtration, and finally a series of plant-derived carbon quantum dots with anti-inflammatory effects were obtained by dialysis and vacuum freeze drying.

Claims

1. A method for preparing plant-derived carbon quantum dots with anti-inflammatory imaging function, comprising the following steps: Step 1: Wash various plant raw materials with anti-inflammatory effects such as woad leaves, pea leaves, broad bean leaves, alfalfa leaves, cornflowers, honeysuckle, rhubarb, selfheal, dandelion leaves, poppy, trichosanthes seeds, mugwort, magnolia petals, etc., homogenize them with a high-speed homogenizer for a certain period of time, then centrifuge the mixture to remove residues and retain the supernatant. Step 2: Vacuum freeze-dry various plants with anti-inflammatory effects to homogenize them into powders. Then mix them with extraction solvents (ultrapure water, 50% ethylene glycol aqueous solution and ethylene glycol) respectively, heat them in a water bath, and then vacuum filter them to collect the filtrate. Step 3: The supernatant and filtrate in step 1 and step 2 are transferred to a stainless steel autoclave lined with polytetrafluoroethylene, and reacted at high temperature for a certain period of time. After cooling to room temperature, centrifugation and filtration are performed to remove large particles in the solution, and finally a series of plant-derived carbon quantum dots with anti-inflammatory effects are obtained by dialysis and vacuum freeze drying. Step 4: The supernatant and filtrate in step 1 and step 2 were transferred to a microwave synthesizer for high temperature treatment. After treatment, they were cooled to room temperature, and large particles in the solution were removed by centrifugation and filtration. The reaction solution was then dialyzed and vacuum freeze-dried to finally obtain a series of plant-derived carbon quantum dots with anti-inflammatory effects.

2. The method for preparing plant-derived carbon quantum dots with anti-inflammatory imaging function according to claim 1, characterized in that: In the step 1, the high-speed homogenization time is 5-1000 min, and the centrifugal speed is 1000-10000 rpm / min.

3. The method for preparing plant-derived carbon quantum dots with anti-inflammatory imaging function according to claim 1, characterized in that: In the step 2, the extraction solvents are ultrapure water, 50% ethylene glycol aqueous solution and ethylene glycol, respectively, the water bath temperature is 50-80° C., and the reaction time is 1-50 h.

4. The method for preparing plant-derived carbon quantum dots with anti-inflammatory imaging function according to claim 1, characterized in that: In the step 3, the hydrothermal reaction temperature is 120-250° C., the time is 2-48 hours, and the centrifugal speed is 1000-90000 rpm / min.

5. The method for preparing plant-derived carbon quantum dots with anti-inflammatory imaging function according to claim 1, characterized in that: In the step 4, the microwave treatment temperature is 120-200° C., the time is 10-60 min, and the centrifugal speed is 1000-90000 rpm / min.

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