Method for producing hydrogen free radicals through microwave catalysis of melanin-like nano material and application

Abstract

The invention discloses a method for producing hydrogen free radicals under microwave catalysis of a melanin-like (polydopamine) nano material and application. The method is simple in synthesis, good in biocompatibility, high in hydrogen free radical yield and low in cost. The method comprises the following steps: (1) dispersing 55 mg of dopamine hydrochloride in a mixture of 100 mL of water and 20 mL of ethanol, and carrying out ultrasonic dispersion; (2) adding 120 mg of tris (hydroxymethyl) aminomethane into the reaction mixture, and stirring at room temperature for 72 hours; (3) centrifuging at 11,000 rpm for 15 minutes, collecting precipitate, and washing the precipitate with ethanol for 3 times; (4) preparing a 100 [mu] g / mL polydopamine normal saline dispersion liquid; and (5) carrying out 2450Hz and 5W microwave treatment, and promoting polar groups in the organic semiconductor to generate oriented polarization in a microwave alternating electric field through semi-quinone defects of the polydopamine, so that a local electric field fluctuates severely, an electron transition potential barrier is reduced, electrons are transited from a valence band to a conduction band, and then water molecules are split to generate hydrogen free radicals.

Description

Technical Field

[0001] The present invention relates to the technical field of nanoscience, and in particular to a method for producing hydrogen free radicals by microwave catalysis of a melanin-like nanomaterial, and an application of the method for producing hydrogen free radicals by microwave catalysis of a melanin-like nanomaterial. Background Art

[0002] As an important active substance, hydrogen radicals have unique redox properties and can react with a wide range of substances such as free radicals, oxidants, metals, and unsaturated bonds. Due to their high reactivity, hydrogen radicals have broad application prospects in biomedicine, environmental governance, energy catalysis, and other fields. However, the current methods for generating hydrogen radicals based on nanomaterials are still limited and have many problems. The defects and shortcomings of existing technologies are as follows:

[0003] 1. Complex synthesis process: The existing catalytic materials (such as DA-type π-conjugated organic photosensitizers and aromatic ketone-substituted cyanine) have cumbersome synthesis steps and complex processes, making them difficult to produce on a large scale.

[0004] 2. Low biocompatibility: Existing catalytic materials have poor biocompatibility, which limits their application in the biomedical field.

[0005] 3. Insufficient hydrogen free radical yield: The catalytic efficiency of existing materials is low, and the yield of hydrogen free radicals cannot meet the needs of practical applications.

[0006] 4. High cost: The preparation cost of existing catalytic materials is high and often requires high energy to excite, which increases the cost of using hydrogen radicals. Summary of the Invention

[0007] In order to overcome the defects of the prior art, the technical problem to be solved by the present invention is to provide a method for producing hydrogen free radicals by microwave catalysis of melanin-like nanomaterials, which has simple synthesis, good biocompatibility, high hydrogen free radical yield and low cost.

[0008] The technical solution of the present invention is: a method for producing hydrogen free radicals by microwave catalysis of melanin-like nanomaterials, which comprises the following steps:

[0009] (1) Disperse 55 mg of dopamine hydrochloride in a mixture of 100 mL of water and 20 mL of ethanol and uniformly disperse the mixture by ultrasonic treatment;

[0010] (2) Add 120 mg of tris(hydroxymethyl)aminomethane to the reaction mixture and stir at room temperature for 72 hours;

[0011] (3) Centrifuge at 11,000 rpm for 15 min, collect the precipitate, and wash the collected precipitate three times with ethanol;

[0012] (4) dispersing the obtained polydopamine melanin nanoparticles in ethanol for later use;

[0013] (5) Disperse 100 μg / mL of polydopamine in normal saline;

[0014] (6) Under microwave treatment at 2450 Hz and 5 W, polydopamine promotes the orientation polarization of polar groups in organic semiconductors in the microwave alternating electric field through the semiquinone radical defect-anion radical doping, resulting in a violent fluctuation of the local electric field. This local electric field can reduce the electron transition barrier, promote the transition of electrons from the valence band to the conduction band, and then split water molecules.

[0015] Produces hydrogen free radicals.

[0016] The beneficial technical effects of the present invention are as follows:

[0017] Simple synthesis: Catalytic materials can be prepared through simple chemical synthesis steps.

[0018] Good biocompatibility: Polydopamine nanomaterials have good biocompatibility and are suitable for use in the biomedical field.

[0019] High hydrogen free radical yield: Polydopamine contains a large number of semiquinone free radicals, which can separate the electron holes of polydopamine under microwave catalysis, and the hydrogen protons in water gain electrons to generate hydrogen free radicals, significantly increasing the yield of hydrogen free radicals.

[0020] Low cost: Under microwave treatment, no high-energy excitation is required, and no additional catalysts or initiators are needed, which reduces the cost of use.

[0021] Also provided is the application of the melanin-like nanomaterial in microwave catalysis to produce hydrogen free radicals, which is applied in microwave dynamic tumor treatment methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The figure is a flow chart of the method for producing hydrogen free radicals by microwave catalysis of melanin-like nanomaterials according to the present invention.

[0023] Figure 2 is a transmission electron microscope TEM image of the polydopamine nanoparticles according to the present invention.

[0024] Figure 3 It is the X-ray photoelectron spectrum XPS spectrum of polydopamine according to the present invention.

[0025] Figure 4 This is the electron paramagnetic resonance (EPR) detection result of hydrogen radicals according to the present invention.

[0026] Figure 5The figure shows the C / C0 comparison curve of 1,1'-diethyl-3,3,3',3'-tetramethylindocarbocyanine iodide Cy3 dye under different treatment conditions in deoxygenated saline under microwave catalysis. C / C0 is defined as the ratio of the dye concentration before and after light irradiation, C0 represents the initial concentration, and C represents the concentration of the reactant at different times.

[0027] Figure 6 The figure shows tumor cells cultured under hypoxic conditions, incubated with polydopamine, and then treated with microwaves, followed by Annexin V-FITC / PI live-dead flow cytometric detection. DETAILED DESCRIPTION

[0028] like Figure 1 As shown, the method for producing hydrogen free radicals by microwave catalysis of melanin-like nanomaterials comprises the following steps:

[0029] (1) Disperse 55 mg of dopamine hydrochloride in a mixture of 100 mL of water and 20 mL of ethanol and uniformly disperse the mixture by ultrasonic treatment;

[0030] (2) Add 120 mg of tris(hydroxymethyl)aminomethane to the reaction mixture and stir at room temperature for 72 hours;

[0031] (3) Centrifuge at 11000 rpm for 15 min, collect the precipitate, and wash the collected precipitate three times with ethanol;

[0032] (4) dispersing the obtained polydopamine melanin nanoparticles in ethanol for later use;

[0033] (5) Disperse 100 μg / mL of polydopamine in normal saline;

[0034] (6) Under microwave treatment at 2450 Hz and 5 W, polydopamine is doped through its semiquinone radical-anion radical, and the polar groups in the organic semiconductor undergo orientation polarization in the microwave alternating electric field, resulting in violent fluctuations in the local electric field. This local electric field can reduce the electron transition barrier, promote the transition of electrons from the valence band to the conduction band, and then split water molecules to produce hydrogen radicals.

[0035] The beneficial technical effects of the present invention are as follows:

[0036] Simple synthesis: Catalytic materials can be prepared through simple chemical synthesis steps.

[0037] Good biocompatibility: Polydopamine melanin nanomaterials have good biocompatibility and are suitable for use in the biomedical field.

[0038] High hydrogen free radical yield: Polydopamine contains a large number of semiquinone free radicals, which can separate the electron holes of polydopamine under microwave catalysis, and the hydrogen protons in water gain electrons to generate hydrogen free radicals, thereby significantly increasing the yield of hydrogen free radicals.

[0039] Low cost: Under microwave treatment, no high-energy excitation is required, and no additional catalysts or initiators are needed, which reduces the cost of use.

[0040] Preferably, the structural formula of polydopamine in step (4) is

[0041]

[0042] Preferably, if Figure 2 、 Figure 3 As shown, the method further includes: characterizing by transmission electron microscopy TEM and X-ray photoelectron spectroscopy XPS to verify that the polydopamine nanoparticles are successfully prepared.

[0043] Preferably, if Figure 4 、 Figure 5 As shown, the method also includes: verifying and detecting the generation of hydrogen free radicals through electron paramagnetic resonance (EPR) spectroscopy and Cy3 dye, 1,1'-diethyl-3,3',3'-tetramethylindocarbocyanine iodide (Cy3) is a typical dye for detecting hydrogen free radicals, and the C=N bond in the Cy3 dye reacts with the hydrogen free radical to reduce the absorbance of the Cy3 dye at 549 nm. The amount of hydrogen free radical generated is characterized by recording the change in the absorption intensity at 549 nm.

[0044] Also provided is the application of the melanin-like nanomaterial in microwave catalysis to produce hydrogen free radicals, which is applied in microwave dynamic tumor treatment methods.

[0045] Preferably, hydrogen radicals are a two-sided regulator that can act as a pro-oxidant under aerobic conditions and as a reducing agent under anoxic conditions. Under aerobic conditions, hydrogen radicals react with O2 to produce superoxide ions O2 ·- , and induce oxidative stress; under hypoxic conditions, hydrogen radicals interfere with intracellular redox homeostasis by attacking close biological targets with relatively high redox potentials (e.g., cytochrome c).

[0046] Due to the adoption of the above technical solution, the present invention has the following technical advantages compared with the prior art:

[0047] 1. Simple synthesis and low cost:

[0048] The present invention prepares polydopamine nanomaterials through simple chemical synthesis steps, eliminating the need for complex processes and equipment, significantly reducing production costs. The synthesis process does not require additional catalysts or initiators, further reducing usage costs.

[0049] 2. Good biocompatibility:

[0050] Polydopamine nanomaterials have good biocompatibility and are suitable for biomedical fields such as antibacterial and anticancer treatments.

[0051] 3. High hydrogen radical yield:

[0052] Polydopamine promotes the orientation polarization of polar groups in organic semiconductors in the microwave alternating electric field through semiquinone radical-anion radical doping, resulting in violent fluctuations in the local electric field. This local electric field can reduce the electron transition barrier, promote the transition of electrons from the valence band to the conduction band, and then split water molecules. [3] , significantly improving the yield of hydrogen free radicals. Since polydopamine contains a large number of semiquinone free radicals, under the action of microwaves, polydopamine can efficiently split water molecules and produce a large number of hydrogen free radicals. Figure 6 The figure shows tumor cells cultured under hypoxic conditions, incubated with polydopamine, and then treated with microwaves (2450 Hz, 5 W, 3 min), followed by Annexin V-FITC / PI live-death flow cytometric detection.

[0053] 4. Efficient and controllable:

[0054] By regulating microwave power, reaction time and the structural characteristics of polydopamine, the generation rate and concentration of hydrogen free radicals can be relatively controlled, thereby achieving efficient and controllable reaction process.

[0055] 5. Environmental friendliness and sustainability:

[0056] The synthesis and use of polydopamine nanomaterials are environmentally friendly, meeting the requirements of green chemistry and sustainable development. Microwave-assisted reaction conditions are mild, energy consumption is low, and the process is highly environmentally friendly.

[0057] 6. Broad application prospects:

[0058] The present invention can be widely used in the fields of organic synthesis, environmental remediation, biomedicine, etc. In organic synthesis, it can be used as an efficient reducing agent or free radical initiator; in environmental remediation, it can be used to degrade organic pollutants; and in biomedicine, it can be used for antibacterial or anticancer treatment.

[0059] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of protection of the technical solution of the present invention.

Claims

1. A method for producing hydrogen free radicals by microwave catalysis of melanin-like nanomaterials, characterized by: It includes the following steps: (1) Disperse 55 mg of dopamine hydrochloride in a mixture of 100 mL of water and 20 mL of ethanol. It is uniformly dispersed by ultrasonic treatment; (2) Add 120 mg of tris(hydroxymethyl)aminomethane to the reaction mixture and stir at room temperature for 72 hours; (3) Centrifuge at 11000 rpm for 15 min, collect the precipitate, and wash the collected precipitate three times with ethanol; (4) suspending the obtained polydopamine-like melanin nanoparticles in ethanol for later use; (5) Disperse 100 μg / mL of polydopamine in normal saline; (6) Under microwave treatment at 2450 Hz and 5 W, polydopamine promotes the orientation polarization of polar groups in organic semiconductors in the microwave alternating electric field through semiquinone radical defect-anion radical doping, resulting in violent fluctuations in the local electric field. The local electric field reduces the electron transition barrier and promotes the transition of electrons from the valence band to the conduction band, thereby splitting water molecules and generating hydrogen radicals.

2. The method for producing hydrogen free radicals by microwave catalysis of melanin-like nanomaterials according to claim 1, characterized in that: The structural formula of the polydopamine in step (4) is:

3. The method for producing hydrogen free radicals by microwave catalysis of melanin-like nanomaterials according to claim 2, characterized in that: The method also includes: characterizing by transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) to verify that the polydopamine nanoparticles are successfully prepared.

4. The method for producing hydrogen free radicals by microwave catalysis of melanin-like nanomaterials according to claim 3, characterized in that: The method also includes: verifying and detecting the generation of hydrogen free radicals through electron paramagnetic resonance (EPR) spectroscopy and 1,1'-diethyl-3,3',3'-tetramethylindocarbocyanine iodide (Cy3) dye. Cy3 is a typical dye for detecting hydrogen free radicals. The C=N bond in the Cy3 dye reacts with the hydrogen free radical, causing the absorbance of the Cy3 dye at 549 nm to decrease. The amount of hydrogen free radical generated is characterized by recording the change in the absorption intensity at 549 nm.

5. The use of the method for producing hydrogen free radicals by microwave catalysis of melanin-like nanomaterials according to claim 1, characterized in that: It is used in microwave dynamic tumor treatment methods.

6. The use of the method for producing hydrogen free radicals by microwave catalysis of melanin-like nanomaterials according to claim 5, characterized in that: Under aerobic conditions, hydrogen radicals react with O2 to produce superoxide anions O2 ·- , and induce oxidative stress; under hypoxic conditions, hydrogen radicals interfere with intracellular redox homeostasis by attacking close biological targets with relatively high redox potential.

7. The use of the method for producing hydrogen free radicals by microwave catalysis of melanin-like nanomaterials according to claim 6, characterized in that: The close biological target is cytochrome c.

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