Preparation method and application of metal-doped self-assembled oligomer carbon dot blocking and controlling agent
By preparing metal-doped self-assembled oligomeric carbon dots, the problem of aflatoxin control has been solved, achieving efficient control and high-purity product production, which is suitable for the prevention and control of aflatoxin.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- DALIAN INSTITUTE OF CHEMICAL PHYSICS CHINESE ACADEMY OF SCIENCES
- Filing Date
- 2024-10-22
- Publication Date
- 2026-04-24
AI Technical Summary
Existing technologies are insufficient to effectively prevent and control the production of aflatoxin, which affects the economic value of crops and human health, especially children's health.
By preparing metal-doped self-assembled oligomeric carbon dots, and utilizing the polymerization reaction of polybasic acids and polyamines, combined with the treatment of precipitants and metal salts, a carbon dot resisting agent with highly efficient resisting properties is formed.
It achieves a high aflatoxin rejection rate of 74.8% to 91.6%, and the preparation method is simple, with few by-products, high product purity and yield, and the metal doping method is fast and efficient.
Smart Images
Figure CN121913484A_ABST
Abstract
Description
Technical Field
[0001] This application relates to a method for preparing and applying a metal-doped self-assembled oligomeric carbon dot inhibitor, which belongs to the field of energy nanomaterials. Background Technology
[0002] Aflatoxins, primarily produced by *Aspergillus flavus* and *Aspergillus parasiticus*, are metabolic products of a class of structurally related toxic fungi. Today, aflatoxins are a global health problem. They not only affect the economic value of crops and reduce animal productivity, but also impact human physical and mental health, especially children who are vulnerable to aflatoxins, leading to growth retardation, developmental delays, liver damage, and liver cancer. Therefore, it is necessary to develop a high-performance, mass-producible inhibitor to achieve efficient prevention and control of aflatoxins.
[0003] Carbon oligomers (CDs) have attracted much attention due to their ease of preparation, chemical inertness, ease of surface modification, low cytotoxicity, and good biocompatibility. Furthermore, self-assembly is one of the important characteristics of CDs, allowing molecules to spontaneously form oriented and ordered structures through intermolecular forces. Doping is one of the effective means to control the physicochemical properties of CDs. Compared with non-metallic atoms, metal ions have more electron orbitals and unoccupied orbitals, as well as larger atomic radii. Doping with metal ions can cause significant changes in the optical, electronic, and magnetic properties of CDs by altering their electron density distribution and band gap. Therefore, metal-doped self-assembled carbon oligomers possess excellent physicochemical properties and are expected to become highly efficient inhibitors of aflatoxin. Summary of the Invention
[0004] According to one aspect of this application, a method for preparing a metal-doped self-assembled oligomer carbon dot resisting agent includes at least the following steps:
[0005] Step I: Mix polybasic acid and polyamine, and polymerize to obtain crude oligomer carbon dots;
[0006] Step II: Dissolve the crude oligomer carbon dots obtained in Step I in a solvent, add a precipitant, and obtain pure oligomer carbon dots;
[0007] Step III: Mix the pure oligomeric carbon dots obtained in Step II with the metal salt and disperse them in the first solvent to form a solution. Add the second solvent until precipitation occurs to obtain the carbon dot inhibitor.
[0008] Optionally, in step I, the polyacid is selected from at least one of propanetricarboxylic acid, glutaric acid, isophthalic acid, citric acid, and tetrafluorosuccinic acid;
[0009] The polyamine is selected from at least one of ethylenediamine, trimethylamine, m-phenylenediamine, o-phenylenediamine, and p-phenylenediamine.
[0010] Optionally, in step I, the molar ratio of the polyacid to the polyamine is 1:0.5 to 5:1.
[0011] Optionally, in step I, the conditions for the polymerization reaction are as follows:
[0012] The polymerization reaction requires a continuous flow of inert gas;
[0013] The polymerization reaction is carried out at a temperature of 120–300°C.
[0014] The polymerization reaction takes 2 to 12 hours.
[0015] Optionally, in step II, the solvent is selected from at least one of acetonitrile, dimethyl sulfoxide, methanol, and ethanol;
[0016] The precipitant is selected from at least one of dichloromethane, water, and acetonitrile.
[0017] Optionally, the volume ratio of the solvent to the precipitant is 1:5 to 1:50.
[0018] Optionally, the molecular weight of the pure oligomeric carbon dots is 2000–7000 Da.
[0019] Optionally, in step III, the metal salt is selected from at least one of ferric chloride, copper chloride, zinc chloride, cobalt chloride, and nickel chloride.
[0020] Optionally, the mass ratio of the carbon dots to the metal salt is 1:0.5 to 5.
[0021] Optionally, in step III, the first solvent is at least one of dimethyl sulfoxide, acetonitrile, methanol, and toluene;
[0022] The second solvent is at least one of ethanol, water, dichloromethane, and trichloromethane.
[0023] Optionally, the concentration of carbon dots in the solution is 0.1–1.0 g / mL.
[0024] Optionally, the volume ratio of the first solvent to the second solvent is 1:3 to 1:30.
[0025] Optionally, the yield of the control agent is 65% to 85%.
[0026] According to a second aspect of this application, an application of a metal-doped self-assembled oligomeric carbon dot inhibitor is provided, the inhibitor inhibiting aflatoxin;
[0027] The inhibition rate of the inhibitor against aflatoxin is 74.8% to 91.6%.
[0028] The beneficial effects that this application can produce include:
[0029] 1) The preparation method provided in this application can reduce the generation of byproducts by using airflow assistance.
[0030] 2) The preparation method provided in this application has advantages such as high purity and high yield.
[0031] 3) The preparation method provided in this application is convenient, quick and efficient in terms of metal doping.
[0032] 4) The preparation method provided in this application allows the metal to exist in multiple valence states simultaneously.
[0033] 5) The metal-doped self-assembled oligomer carbon dot inhibitor provided in this application has an inhibitory effect on aflatoxin. Attached Figure Description
[0034] Figure 1 This is a TEM image of the self-assembled oligomeric carbon dots in Example 1 of this application;
[0035] Figure 2 This is the mass spectrum of the self-assembled oligomeric carbon dots in Example 1 of this application;
[0036] Figure 3 The infrared spectrum of the self-assembled oligomeric carbon dots in Example 1 of this application;
[0037] Figure 4 This is the UV absorption spectrum of the self-assembled oligomeric carbon dots before and after metal doping in Example 1 of this application;
[0038] Figure 5 The image shows the XRD patterns of the self-assembled oligomer carbon dots before and after metal doping in Example 1 of this application. Detailed Implementation
[0039] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.
[0040] Unless otherwise specified, the raw materials and solvents used in the embodiments of this application were all purchased commercially.
[0041] The analysis method in the embodiments of this application is as follows:
[0042] The morphology of carbon dot materials was analyzed using transmission electron microscopy.
[0043] The molecular structure of carbon dot materials was analyzed using ultra-high performance liquid chromatography / quadrupole time-of-flight mass spectrometry.
[0044] The crystal structure of carbon dot materials was analyzed using an X-ray diffractometer.
[0045] The yield of carbon dot materials in the embodiments of this application is calculated as follows:
[0046] In the embodiments of this application, the yield of carbon dot materials is calculated based on 0.1 moles:
[0047] The yield of carbon dot materials = total mass after synthesis / total mass of precursors.
[0048] According to one embodiment of this application, a method for preparing a metal-doped self-assembled oligomer carbon dot resistive agent and its application specifically include the following steps:
[0049] (1) The solid mixture of polycarboxylic acids and polyamines was subjected to dehydration polymerization under high temperature conditions by air-flow assisted melt polymerization.
[0050] (2) By adjusting the reaction temperature, reaction time and the molar ratio of polycarboxylic acid to polyamine compound, oligomeric carbon dots with self-assembly properties are obtained.
[0051] (3) The self-assembled oligomer carbon dots and metal salts are dispersed in the first solvent and stirred evenly.
[0052] (4) Slowly add the second solvent until precipitation occurs, and filter and dry the precipitate to obtain metal-doped self-assembled oligomer carbon dot inhibitor.
[0053] The polycarboxylic acids mentioned in step (1) include at least one of propanetricarboxylic acid, glutaric acid, isophthalic acid, citric acid, and tetrafluorosuccinic acid.
[0054] The polyamine compound mentioned in step (1) is at least one of ethylenediamine, trimethylamine, m-phenylenediamine, o-phenylenediamine, and p-phenylenediamine;
[0055] The molar ratio of the polycarboxylic acid to the polyamine in step (2) is 1:0.5 to 5.0;
[0056] The reaction temperature described in step (2) is 120–300°C;
[0057] The reaction time described in step (2) is 2 to 12 hours;
[0058] The molecular weight mentioned in step (2) is 2000-7000 Da;
[0059] The metal salt mentioned in step (3) is one of ferric chloride hexahydrate, copper chloride dihydrate, zinc chloride monohydrate, cobalt chloride hexahydrate, and nickel chloride hexahydrate;
[0060] The first solvent mentioned in step (3) is one of dimethyl sulfoxide, acetonitrile, methanol, and toluene;
[0061] The mass ratio of the self-assembled oligomer carbon dots to the metal salt in step (3) is 1:0.5 to 5;
[0062] The second solvent mentioned in step (4) is one of ethanol, water, dichloromethane, and trichloromethane;
[0063] The yield of the metal-doped self-assembled oligomer carbon dot resist agent in step (4) is 65% to 85%.
[0064] Example 1
[0065] (1) Weigh 1.0 mol of propanetricarboxylic acid and 1.0 mol of ethylenediamine solid powder, place them in a mortar and grind them together. Transfer to a container with a 100 cm³ flow channel. 3 In a high-temperature tube furnace with nitrogen at a rate of 20℃ / min, the temperature was increased and the polymerization reaction was carried out at 200℃ for 6 hours. After cooling, the crude product was obtained.
[0066] (2) Grind 0.6g of the crude product from step (1) into powder and put it into a 100mL beaker. Add 5mL of acetonitrile to completely dissolve it, and then add 50mL of dichloromethane to produce a precipitate. Then, vacuum dry the precipitate at 30℃ for 30min to obtain the purified self-assembled oligomer carbon dots with a yield of about 76.8% and an average molecular weight of 3000Da.
[0067] (3) Dissolve 0.3g of self-assembled oligomer carbon dots in 5mL of dimethyl sulfoxide, sonicate for 10min, then add 0.6g of ferric chloride hexahydrate, stir continuously for 60min, then add 30mL of ethanol to produce a precipitate, and vacuum dry the precipitate at 60℃ for 6h to obtain metal-doped self-assembled oligomer carbon dot inhibitors with a yield of about 67.4%.
[0068] (4) Take 0.01g of the metal-doped self-assembled oligomer carbon dot inhibitor obtained in step (3) and dissolve it in 100mL of water to prepare a solution with a concentration of 100μg / mL. The inhibitory rate of aflatoxin was 91.6%.
[0069] The results showed that the self-assembled oligomeric carbon dots were spherical with an average particle size of 3.03 nm (see results). Figure 1 Mass spectrometry results showed that the product was an oligomer with no obvious impurity peaks (see...). Figure 2 It contains carboxyl, amino, and other groups (see...). Figure 3 This is beneficial for metal doping. Furthermore, the self-assembled oligomeric carbon dots exhibit a significant absorption peak at 258 nm; after metal doping, the absorption peak is significantly enhanced and shifts to 264 nm (see...). Figure 4 This is beneficial for generating photogenerated electrons. Simultaneously, a significant large bulge at 18° indicates that the material has an amorphous structure, and the XRD peak intensity is significantly enhanced after doping (see...). Figure 5 ).
[0070] Example 2
[0071] (1) Weigh 1.0 mol of glutaric acid and 1.5 mol of m-phenylenediamine solid powder, place them in a mortar and grind them together. Transfer to a container with a 100 cm³ well. 3 In a high-temperature tube furnace with nitrogen at a rate of 20℃ / min, the temperature was increased and the polymerization reaction was carried out at 250℃ for 8 hours. After cooling, the crude product was obtained.
[0072] (2) Grind 0.5g of the crude product from step (1) into powder and put it into a 100mL beaker. Add 3mL of dimethyl sulfoxide to completely dissolve it, and then add 50mL of water to produce a precipitate. Then, vacuum dry the precipitate at 65℃ for 6h to obtain the purified self-assembled oligomer carbon dots with a yield of about 68.1% and an average molecular weight of 4500Da.
[0073] (3) Dissolve 0.5g of self-assembled oligomer carbon dots in 5mL of acetonitrile, sonicate for 10min, then add 1.0g of copper chloride dihydrate, stir continuously for 40min, then add 50mL of dichloromethane to produce a precipitate, and vacuum dry the precipitate at 30℃ for 30min to obtain metal-doped self-assembled oligomer carbon dot inhibitor with a yield of about 74.7%.
[0074] (4) Take 0.01g of the metal-doped self-assembled oligomer carbon dot inhibitor obtained in step (3) and dissolve it in 100mL of water to prepare a solution with a concentration of 100μg / mL. The inhibitory rate of aflatoxin was 85.6%.
[0075] Example 3
[0076] (1) Weigh 1.0 mol of isophthalic acid and 0.5 mol of trimethylamine solid powder, place them in a mortar and grind them together. Transfer to a container with a 100 cm³ flow channel. 3 In a high-temperature tube furnace with nitrogen at a rate of 20℃ / min, the temperature was increased and the polymerization reaction was carried out at a constant temperature of 180℃ for 5 hours. After cooling, the crude product was obtained.
[0077] (2) Grind 0.6g of the crude product from step (1) into powder and put it into a 100mL beaker. Add 3mL of ethanol to completely dissolve it, and then add 30mL of dichloromethane to produce a precipitate. Then, vacuum dry the precipitate at 45℃ for 1h to obtain the purified self-assembled oligomer carbon dots with a yield of about 81.4% and an average molecular weight of 6300Da.
[0078] (3) Dissolve 0.6 g of self-assembled oligomer carbon dots in 8 mL of methanol, sonicate for 10 min, then add 0.3 g of zinc chloride monohydrate, stir continuously for 30 min, then add 50 mL of chloroform to produce a precipitate, and vacuum dry the precipitate at 40 °C for 45 min to obtain metal-doped self-assembled oligomer carbon dot inhibitors with a yield of about 68.9%.
[0079] (4) Take 0.01g of the metal-doped self-assembled oligomer carbon dot inhibitor obtained in step (3) and dissolve it in 100mL of water to prepare a solution with a concentration of 100μg / mL. The inhibitory rate of aflatoxin was 86.4%.
[0080] Example 4
[0081] (1) Weigh 1.0 mol of citric acid and 2.5 mol of o-phenylenediamine solid powder, put them into a mortar and grind them together. Transfer them to a high-temperature tube furnace with nitrogen gas at a rate of 100 cm3 / min, heat them at a rate of 20 °C / min, and polymerize them at a constant temperature of 280 °C for 10 h. After cooling, the crude product is obtained.
[0082] (2) Grind 0.5g of the crude product from step (1) into powder and put it into a 100mL beaker. Add 10mL of ethanol to completely dissolve it, and then add 80mL of water to produce a precipitate. Then, vacuum dry the precipitate at 65℃ for 5h to obtain the purified self-assembled oligomer carbon dots with a yield of about 74.8% and an average molecular weight of 7100Da.
[0083] (3) Dissolve 0.3g of self-assembled oligomer carbon dots in 6mL of toluene, sonicate for 20min, then add 1.5g of cobalt chloride hexahydrate, stir continuously for 60min, then add 60mL of ethanol to produce a precipitate, and vacuum dry the precipitate at 60℃ for 60min to obtain metal-doped self-assembled oligomer carbon dot inhibitors with a yield of about 75.6%.
[0084] (4) Take 0.01g of the metal-doped self-assembled oligomer carbon dot inhibitor obtained in step (3) and dissolve it in 100mL of water to prepare a solution with a concentration of 100μg / mL. The inhibitory rate of aflatoxin was 83.4%.
[0085] Example 5
[0086] (1) Weigh 1.0 mol of tetrafluorosuccinic acid and 0.5 mol of p-phenylenediamine solid powder, place them in a mortar and grind them together. Transfer to a container with a 100 cm³ flow channel. 3 In a high-temperature tube furnace with nitrogen at a rate of 20℃ / min, the temperature was increased and the polymerization reaction was carried out at 250℃ for 6 hours. After cooling, the crude product was obtained.
[0087] (2) Grind 0.6g of the crude product from step (1) into powder and put it into a 100mL beaker. Add 5mL of dimethyl sulfoxide to completely dissolve it, and then add 50mL of acetonitrile to produce a precipitate. Then, vacuum dry the precipitate at 65℃ for 1h to obtain the purified self-assembled oligomer carbon dots with a yield of about 78.6% and an average molecular weight of 5200Da.
[0088] (3) Dissolve 0.5g of self-assembled oligomer carbon dots in 5mL of acetonitrile, sonicate for 10min, then add 0.1g of zinc chloride monohydrate, stir continuously for 45min, then add 50mL of chloroform to produce a precipitate, and vacuum dry the precipitate at 45℃ for 60min to obtain metal-doped self-assembled oligomer carbon dot inhibitor with a yield of about 67.5%.
[0089] (4) Take 0.01g of the metal-doped self-assembled oligomer carbon dot inhibitor obtained in step (3) and dissolve it in 100mL of water to prepare a solution with a concentration of 100μg / mL. The inhibitory rate of aflatoxin was 87.3%.
[0090] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.
Claims
1. A method for preparing a metal-doped self-assembled oligomer carbon dot resistive agent, characterized in that, At least the following steps are included: Step I: Mix polybasic acid and polyamine, and polymerize to obtain crude oligomer carbon dots; Step II: Dissolve the crude oligomer carbon dots obtained in Step I in a solvent, add a precipitant, and obtain pure oligomer carbon dots; Step III: Mix the pure oligomeric carbon dots obtained in Step II with the metal salt and disperse them in the first solvent to form a solution. Add the second solvent until precipitation occurs to obtain the carbon dot inhibitor.
2. The preparation method according to claim 1, characterized in that, In step I, the polybasic acid is selected from at least one of propanetricarboxylic acid, glutaric acid, isophthalic acid, citric acid, and tetrafluorosuccinic acid; The polyamine is selected from at least one of ethylenediamine, trimethylamine, m-phenylenediamine, o-phenylenediamine, and p-phenylenediamine.
3. The preparation method according to claim 1, characterized in that, In step I, the molar ratio of the polyacid to the polyamine is 1:0.5 to 5:
1.
4. The preparation method according to claim 1, characterized in that, In step I, the conditions for the polymerization reaction are as follows: The reaction requires a continuous flow of inert gas; The polymerization reaction is carried out at a temperature of 120–300°C. The polymerization reaction takes 2 to 12 hours.
5. The preparation method according to claim 1, characterized in that, In step II, the solvent is selected from at least one of acetonitrile, dimethyl sulfoxide, methanol, and ethanol; The precipitant is selected from at least one of dichloromethane, water, and acetonitrile; Preferably, the volume ratio of the solvent to the precipitant is 1:5 to 1:30; Preferably, the molecular weight of the pure oligomeric carbon dots is 2000-7000 Da.
6. The preparation method according to claim 1, characterized in that, In step III, the metal salt is selected from at least one of ferric chloride, copper chloride, zinc chloride, cobalt chloride, and nickel chloride; Preferably, the mass ratio of the carbon dots to the metal salt is 1:0.5 to 5.
7. The preparation method according to claim 1, characterized in that, In step III, the first solvent is at least one of dimethyl sulfoxide, acetonitrile, methanol, and toluene; The second solvent is at least one of ethanol, water, dichloromethane, and trichloromethane.
8. The preparation method according to claim 1, characterized in that, In the solution, during step III, the concentration of the carbon dots is 0.1–1.0 g / mL; Preferably, the volume ratio of the first solvent to the second solvent is 1:3 to 1:
30.
9. The preparation method according to claim 1, characterized in that, The yield of the control agent is 65% to 85%.
10. The application of a metal-doped self-assembled oligomeric carbon dot resistive agent, characterized in that, The inhibitor blocks aflatoxin; The inhibition rate of the inhibitor against aflatoxin is 74.8% to 91.6%; The control agent is prepared by any one of the preparation methods in claims 1 to 9.