Active oxygen free radical generation method based on calcium fluoride and application of active oxygen free radical generation method

Abstract

The invention discloses a method for generating active oxygen free radicals based on calcium fluoride and application of the active oxygen free radicals. The method comprises the following steps: adding calcium fluoride into water, mixing and reacting to generate active oxygen free radicals OH and O < 2->; according to the principle of generating the reactive oxygen free radicals, calcium fluoride and an aqueous solution are adopted to form a solid-liquid interface, interface contact is promoted through vortex or ultrasonic waves, water molecules and hydroxyl ions are induced to lose electrons and generate OH through the contact electrification effect, and CaF2 captures the electrons to form CaF2 with negative electricity; then, O2 obtains electrons from CaF2, and O2 <-> is generated; the method can be used in the fields of environmental pollutant degradation and drug preparation. The function and mechanism of the CaF2 for catalyzing H2O and O2 to generate OH and O2-reactive oxygen free radicals are found for the first time, new application of the CaF2 is widened, an important scientific basis is provided for developing a novel catalysis strategy, and the CaF2 has important theoretical and application values.

Description

Technical Field

[0001] The invention belongs to the field of environmental pollutant degradation and disease treatment, and relates to a method for generating active oxygen free radicals based on calcium fluoride and application thereof. Background Art

[0002] Reactive oxygen species (ROS) are a class of molecules with high reactivity, including hydroxyl radicals • OH, superoxide anion radicals • O2 - In biological systems, excessive intracellular reactive oxygen species (ROS) can cause apoptosis through various mechanisms. Therefore, ROS can be used to develop treatments for various diseases, such as photodynamic therapy (PDT), sonodynamic therapy (SDT), and chemodynamic therapy (CDT). Furthermore, ROS also plays an important role in environmental protection, degrading organic pollutants and achieving water and air purification.

[0003] Traditional catalytic reactions involving reactive oxygen species (ROS) have numerous limitations when applied to biological systems. For one thing, the substrates for the reactions are limited. Common substrates such as O₂ and H₂O₂ may not be present at concentrations sufficient to support efficient ROS production in certain specific biological environments, such as the tumor microenvironment. This limits the effective concentration of ROS, making it difficult for them to fully exert their biological activity. Furthermore, the complexity of the biological environment can also affect the efficiency and selectivity of the catalytic reaction, resulting in low ROS generation efficiency, making it difficult to meet the needs of practical applications such as disease treatment.

[0004] Similar problems are also faced in the process of active oxygen generation in the field of environmental protection. For example, in some wastewater treatment technologies, the traditional Fenton method requires the use of Fe 2+ It catalyzes H2O2 to generate active oxygen, but this method has problems such as a narrow pH value range, large amounts of iron sludge generated, and difficulty in catalyst recovery, which limit its large-scale application and treatment effect.

[0005] Calcium fluoride (CaF2) is a common inorganic fluoride with high chemical stability and good biocompatibility. It has been widely used in industrial and medical fields, such as optical materials, ceramic manufacturing, and dental materials. In recent years, with the in-depth study of the properties of calcium fluoride, its potential application in catalysis has gradually attracted attention. However, current research mainly focuses on specific reactions, such as using calcium fluoride as a co-catalyst to improve the activity and selectivity of certain organic reactions. However, relatively little research has been conducted on calcium fluoride's role in the generation of reactive oxygen species.

[0006] Recent studies have shown that through specific methods and technical means, the catalytic activity of calcium fluoride can be stimulated, allowing it to play an important role in the generation of reactive oxygen species. For example, under specific conditions such as light, electric field, or ultrasound, processes such as electron transfer may occur on the surface of calcium fluoride, thereby promoting the reaction of hydrogen peroxide molecules or other redox substances to generate reactive oxygen free radicals. However, these studies are still in the preliminary exploratory stage, and the mechanism of calcium fluoride catalyzing the generation of reactive oxygen species has not yet been fully clarified. Its catalytic efficiency and reactive oxygen yield still need to be further improved, and its potential and advantages in different application scenarios also need to be further explored.

[0007] In summary, exploring new methods for generating reactive oxygen species based on calcium fluoride is crucial for overcoming the limitations of existing reactive oxygen species generation technologies and expanding their applications in disease treatment, environmental protection, and other fields. By further studying the catalytic properties of calcium fluoride and optimizing reaction conditions and systems, it is hoped that efficient, stable, and low-cost reactive oxygen species generation technologies will be developed, providing new insights and approaches for solving practical problems in related fields. Summary of the Invention

[0008] The purpose of the present invention is to explore the catalytic potential of calcium fluoride and provide a new method for generating active oxygen free radicals based on calcium fluoride and its application. The method of the present invention utilizes a catalytic reaction system composed of calcium fluoride and water to generate •OH and •O2 under vortex or ultrasonic conditions. - The mechanism of the catalytic reaction is as follows Figure 1 As shown in the figure: When the "solid-liquid" interface contacts between calcium fluoride and the water phase, electron transfer occurs on the interface, that is, the fluorine atoms with stronger electronegativity are transferred from H2O or OH - The electrons are captured, making calcium fluoride negatively charged (CaF2 ), while H2O or OH - It loses electrons and generates •OH; then, O2 in water reacts with CaF2 Collision occurs, from CaF2 Capture electrons and generate •OH. This invention provides a new method for generating active oxygen free radicals based on calcium fluoride. It is the first time to discover that calcium fluoride reacts with water at the "solid-liquid" interface to generate •OH and •O2 - The present invention will broaden the new applications of calcium fluoride in the biomedical and environmental fields, provide an important scientific basis for the development of new catalytic strategies, and has important theoretical and application value.

[0009] The purpose of the present invention is achieved through the following technical solutions: A new method for generating active oxygen free radicals based on calcium fluoride comprises the following steps: adding calcium fluoride to water and mixing to react to generate active oxygen free radicals. The active oxygen free radicals include •OH and •O2 -.

[0010] Furthermore, in the catalytic reaction system formed by adding calcium fluoride to water, the concentration of calcium fluoride is preferably 0.03-2.00 g / mL.

[0011] Furthermore, the reaction of adding calcium fluoride to water and mixing is preferably carried out under vortexing or ultrasonic conditions, and the reaction temperature is preferably room temperature. Vortexing or ultrasonication promotes "solid-liquid" interface contact between CaF2 and the aqueous solution, causing electron transfer at the interface. Electrons can be transferred from water and hydroxide ions to CaF2 to generate •OH, and CaF2 carries a negative charge (CaF2 ). Subsequently, O2 can be removed from the negatively charged CaF2 (CaF2 ) acquire electrons to produce •OH and •O2 - .

[0012] The calcium fluoride-based active oxygen radical generation method is used in the field of environmental pollutant degradation. The pollutants that can react with active oxygen to be degraded include methylene blue, terephthalic acid, etc.

[0013] A method for degrading environmental pollutants comprises the following steps: adding calcium fluoride to water containing pollutants and performing vortex or ultrasonic treatment.

[0014] Application of calcium fluoride in the field of environmental pollutant degradation or in the preparation of environmental pollutant degradation agents.

[0015] A method for disinfecting and sterilizing an aqueous solution comprises the following steps: adding calcium fluoride to the aqueous solution to be disinfected and sterilized, and performing vortex or ultrasonic treatment.

[0016] The invention relates to the use of calcium fluoride in the preparation of medicines, medical catalytic materials or disinfectants. The medicines are indicated for diseases that can be treated by reactive oxygen species, including cancer, infectious diseases, autoimmune diseases, neurodegenerative diseases, cardiovascular diseases, etc. The cancers include breast cancer, liver cancer, lung cancer, skin cancer, etc. The infectious diseases include bacterial inflammation, fungal infection, viral infection, etc. The autoimmune diseases include rheumatoid arthritis, multiple sclerosis, etc. The neurodegenerative diseases include Alzheimer's disease, Parkinson's disease, etc. The cardiovascular diseases include ischemic heart disease, peripheral arterial disease, etc.

[0017] An environmental pollutant degrader, a medicine, a medical catalytic material, or a disinfectant, comprising calcium fluoride.

[0018] Beneficial effects of the present invention: (1) The present invention provides a new method for generating active oxygen free radicals based on calcium fluoride. Calcium fluoride reacts with aqueous solution at the solid-liquid interface to produce •OH and •O2 - The ability to detect and treat pollutants provides a new direction for environmental pollution control, disinfection and sterilization, and disease treatment.

[0019] (2) The calcium fluoride used in the present invention is a clinical drug, which helps to promote the clinical application of this method.

[0020] (3) The preparation method of calcium fluoride is simple and its catalytic performance is stable, which is conducive to clinical application.

[0021] (4) This invention provides an important scientific basis for the development of new catalytic strategies and has important theoretical and application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a diagram showing the mechanism of the calcium fluoride-based active oxygen radical generation method of the present invention.

[0023] Figure 2 This is a transmission electron micrograph of calcium fluoride.

[0024] Figure 3 (a) DMPO-•OH and (b) DMPO-•O2 in vortexed CaF2-H2O - Electron spin resonance spectra, and (c) DMPO-•OH electron spin resonance spectra of CaF2-H2O treated with vortex or ultrasound.

[0025] Figure 4 The DMPO-•OH electron spin resonance spectra of calcium fluoride-H2O treated by vortex at different pH values ​​are shown.

[0026] Figure 5 It is the UV-visible absorption spectrum of methylene blue after vortex or ultrasonic treatment in the presence of calcium fluoride. Control is the control group without any treatment.

[0027] Figure 6 This is the distribution diagram of Escherichia coli colonies in the solution under different treatments. DETAILED DESCRIPTION

[0028] The present invention is further described below by the following non-limiting examples. It should be understood that these examples are only some preferred technical solutions of the present invention, and the protection scope of the present invention is not limited to these examples.

[0029] Example 1 Preparation and Characterization of Calcium Fluoride Preparation: Calcium fluoride was prepared by adding a 1 M sodium fluoride (NaF) aqueous solution to a 0.5 M calcium chloride (CaCl2) aqueous solution (30 mL) and stirring for 1 hour. After standing at 25°C for 24 hours, the resulting precipitate was centrifuged and washed three times with deionized water and three times with anhydrous ethanol at 10,000 rpm. The solid calcium fluoride was then dried at 60°C and used in the following examples.

[0030] Characterization: Transmission electron microscopy showed that the calcium fluoride prepared in this example has a typical cubic morphology ( Figure 2 ).

[0031] Example 2 Evaluation of the performance of calcium fluoride in generating active oxygen free radicals in aqueous solution Calcium fluoride (0.1 g) was added to an aqueous solution containing 5,5-dimethyl-1-pyrroline-N-oxide (DMPO, 10 mM) or a methanol solution containing DMPO (10 mM) to a final volume of 0.4 mL. The solution was then vortexed (700 rpm) or sonicated (30 kHz, 2.0 W / cm 2 ) for 10 minutes. The ESR spectrum of the mixed solution was measured by an electron paramagnetic resonance (ESR) spectrometer (Brukermagnettech ESR5000, Germany). The purpose of the presence of methanol is to eliminate the influence of the •OH signal during the test process, otherwise DMPO-•O2 cannot be detected. - According to ESR test, calcium fluoride can produce •OH and •O2 under vortex and ultrasonic conditions. - , showing that it belongs to DMPO-•OH and DMPO-•O2 - The spectral characteristic signal peaks are significant, and ultrasound produces a higher content of •OH than vortex ( Figure 3 ). In addition, calcium fluoride solution under vortex can produce •OH in the pH range of 5-9, such as Figure 4 As shown in the figure, in alkaline solution, the signal of DMPO-•OH is stronger than that in acidic solution. This is attributed to the fact that part of the transferred electrons in calcium fluoride come from -OH, while H2O obtains electrons from negatively charged calcium fluoride through solid-liquid contact electrification to form •OH. Therefore, the more -OH content in water, the more •OH is produced.

[0032] Example 3: Degradation of the environmental pollutant methylene blue (MB) using calcium fluoride Calcium fluoride was added to an aqueous solution containing MB and then subjected to either ultrasonic or vortex treatment. The UV-visible absorption spectrum of MB was recorded. The specific experimental procedure was as follows: Calcium fluoride (0.1 g) was added to an aqueous solution containing MB (10 µg / mL) to a total volume of 3 mL. The solution was vortexed (700 rpm) or ultrasonicated (30 kHz, 2.0 W / cm 2 ) for 10 minutes. Subsequently, the mixed solution was subjected to ultrafiltration centrifugation (10,000 rpm). Finally, the absorbance change of MB was measured by UV-visible absorption spectroscopy. The results are shown in Figure 5 After vortexing for 10 minutes, MB was degraded due to the generation of reactive oxygen species, resulting in a decrease in absorbance at 664 nm, with a degradation rate of 32.6%. Under the same ultrasonic treatment conditions, the decrease in MB absorbance was even more significant, with a degradation rate of 54.2%. This demonstrates that calcium fluoride reacts with aqueous solution at the solid-liquid interface to produce •OH and •O2 - The ultrasound induced a higher frequency of electron exchange in the calcium fluoride-water "solid-liquid" interface, generating more reactive oxygen free radicals.

[0033] Example 4: Calcium fluoride is used to sterilize Escherichia coli A single colony of E. coli was grown overnight in LB broth at 37°C and 160 rpm. The overnight culture was diluted 1:100 and incubated for another 4 hours to ensure that the bacteria were in the logarithmic growth phase. The bacterial suspension (1.0 × 10 7 CFU / mL) were centrifuged (4000 rpm, 5 min), washed three times with 0.9% NaCl solution, and then resuspended in a solution containing calcium fluoride (300 μg / mL) as the experimental group, and the solution suspended with only 0.9% NaCl was used as the control group. After incubation for 1 hour, the bacterial suspension in the calcium fluoride group was vortexed for 10 minutes or not vortexed. The bacterial suspension without any treatment was used as a blank control. The bacterial suspension of each treatment group was diluted and evenly spread on LB agar plates, and the colony forming units were counted after overnight incubation. Figure 6 As shown in the figure, calcium fluoride without vortex treatment has a low killing effect on bacteria. Compared with the control group, the Escherichia coli in the solution of calcium fluoride in the vortex treatment group was almost completely eliminated, indicating that the ROS produced by calcium fluoride has a strong bacterial killing ability.

[0034] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent replacements and improvements made by any technician familiar with this technical field within the technical scope disclosed by the present invention should be included in the scope of protection of the invention.

Claims

1. A method for generating active oxygen free radicals based on calcium fluoride, characterized in that: The following steps are involved: Calcium fluoride is added to water and mixed to react to generate active oxygen free radicals; the active oxygen free radicals include •OH and •O2 - .

2. The method for generating active oxygen free radicals based on calcium fluoride according to claim 1, wherein: In the catalytic reaction system formed by adding calcium fluoride to water and mixing them, the concentration of calcium fluoride is 0.05-2.00 g / mL.

3. The method for generating active oxygen free radicals based on calcium fluoride according to claim 1, characterized in that: The reaction is carried out under vortexing or ultrasonic conditions.

4. Application of the method for generating active oxygen free radicals based on calcium fluoride according to any one of claims 1 to 3 in the field of environmental pollutant degradation, characterized in that: The pollutants can react with active oxygen to be degraded.

5. The use according to claim 4, characterized in that: The pollutants include methylene blue and terephthalic acid.

6. A method for degrading environmental pollutants or a method for disinfecting an aqueous solution, characterized in that: The following steps are involved: Calcium fluoride is added to water containing pollutants or to an aqueous solution to be disinfected and sterilized, and vortex or ultrasonic treatment is performed; the pollutants can react with active oxygen to be degraded.

7. Application of calcium fluoride in the field of environmental pollutant degradation or in the preparation of environmental pollutant degradation agents.

8. Application of calcium fluoride in the preparation of medicines, medical catalytic materials or disinfectants, characterized in that: The drug is indicated for diseases that can be treated by active oxygen.

9. The use of calcium fluoride according to claim 8 in the preparation of medicines, medical catalytic materials or disinfectants, characterized in that: The diseases that can be treated by active oxygen include cancer, infectious diseases, autoimmune diseases, neurodegenerative diseases, and cardiovascular diseases.

10. An environmental pollutant degrading agent, a medicine, a medical catalytic material, or a disinfectant, characterized in that: Contains calcium fluoride.

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