Preparation and application of ROS (reactive oxygen species) sensitive liposome nanoparticles (Quu-NPs) for mitochondrial delivery of quercetin

Abstract

The invention discloses preparation and application of ROS (reactive oxygen species) sensitive liposome nanoparticles (Quu-NPs) for mitochondrial delivery of quercetin. DSPE and PEG2000 are used as main framework materials of the functional liposome, an ROS response group TK-COOH and a mitochondrial targeting molecule TPP-COOH are introduced to prepare the functional liposome, and the functional liposome, soybean lecithin and cholesterol are used as a shell of the liposome according to a proper proportion to wrap a lipophilic component quercetin. The material has good biocompatibility and fat solubility, the bioavailability and solubility of the quercetin can be effectively improved, the quercetin is enriched in mitochondria, controlled release of the quercetin is achieved according to the ROS level, the peak valley phenomenon and toxic and side effects of systemic administration are avoided, and the mitochondrial dysfunction resistance of the quercetin is effectively enhanced.

Description

Technical Field

[0001] The invention relates to a functional liposome and a preparation method and application thereof, and in particular to the preparation and application of ROS-sensitive liposome nanoparticles for mitochondrial delivery of quercetin, belonging to the technical field of liposomes. Background Art

[0002] Fine particulate matter (PM2.5) has become a major public health issue due to its adverse effects on health. The number of diseases and deaths caused by it is increasing year by year. There is increasing evidence that PM2.5 has an important impact on the development of respiratory diseases such as chronic obstructive pulmonary disease, asthma and idiopathic pulmonary fibrosis. PM2.5 deposits in lung tissue and can cause pathological damage to lung tissue and cells, especially abnormal changes in mitochondrial structure and function. Studies have shown that mitochondria are the main target of PM2.5. PM2.5 causes NOX4 / Nrf2 redox imbalance in cells in a dose-dependent manner to induce oxidative stress, resulting in a significant increase in mitochondrial ROS production, a decrease in membrane potential, and a significant increase in the levels of mitochondrial fission proteins cyto-c, AIF and DRP1, and inhibits the expression of mitochondrial metabolic protein SIRT3, causing mitochondrial damage; at the same time, PM2.5 can promote the expression of autophagy proteins LC3-II and ATG3, inhibit the expression levels of p62 and mTOR, leading to mitochondrial vacuolation and destruction of mitochondrial structure; PM2.5 exposure can also lead to a decrease in the level of mitochondrial fusion protein MFN2, an increase in the level of fission protein FIS1, a decrease in ATP, and an increase in the opening of mitochondrial permeability transition pores to disrupt mitochondrial homeostasis.

[0003] Quercetin is an important flavonoid compound that is widely found in many plants. Quercetin has good antioxidant, free radical scavenging, anti-tumor, anti-inflammatory, and antibacterial effects. Quercetin can play a therapeutic role in MD independently of its free radical scavenging properties. Quercetin can significantly reduce the level of mtROS induced by external stimuli, inhibit the expression of Drp1 and mitochondrial depolarization, restore Δψm, reduce mtDNA damage, improve mitochondrial morphology and quantity, and inhibit the decrease of reduced glutathione (GSH) levels in mitochondria induced by heavy metal ions, restore ATP levels, and protect cells from apoptosis caused by stimulation. However, the concentration of quercetin used in in vitro experimental models involving isolated mitochondria may not be reached in vivo; at the same time, low solubility and low absorption levels as well as rapid metabolism are the main factors causing the low bioavailability of quercetin, which is not conducive to quercetin fully exerting its anti-mitochondrial dysfunction effect. Summary of the invention

[0004] The purpose of the present invention is to provide a preparation and application of ROS-sensitive liposome nanoparticles (Qu@NPs) for mitochondrial delivery of quercetin.

[0005] The present invention is achieved through the following technical solutions:

[0006] A method for preparing Qu@NPs, characterized in that it comprises the following steps:

[0007] Step 1: Synthesize ROS-sensitive bonds

[0008] ROS response element TK-COOH, the steps for synthesizing TK-COOH are as follows:

[0009] (1) Slowly drip an appropriate amount of 3-mercaptopropionic acid into a round-bottom flask filled with excess anhydrous acetone and place it in an ice-water bath;

[0010] (2) Slowly drop an appropriate amount of trifluoroacetic acid into the round-bottom flask, place the mixture on a magnetic stirrer, and continue stirring the mixture for 12 h after returning to room temperature;

[0011] (3) After the reaction is completed, the mixture is placed on ice until it is completely crystallized to quench the reaction, and the precipitate is filtered out, washed with cold n-hexane and ice water, and dried to obtain TK-COOH;

[0012] Step 2: Synthesis of mitochondria-targeted, ROS-sensitive liposomes

[0013] The mitochondria-targeted, ROS-sensitive liposome is DTPT. The steps for synthesizing DTPT are as follows:

[0014] The mixture was placed in a dry round-bottom flask, and a chloroform / DMF mixed solvent was added to the round-bottom flask to obtain a mixed solution, which was then placed on a magnetic stirrer and reacted at room temperature for 24 hours. After the reaction was completed, the reaction was stopped in an ice-water bath, and the solvent was removed by a rotary evaporator to obtain a solid, which was washed and dialyzed in deionized water for 24 hours using a dialysis bag and dried to obtain DSPE-TK-COOH;

[0015] (2) TPP-COOH, PEG2000, DMAP and EDCI were mixed uniformly in a molar ratio of 1-1.2:1:3-6:1-3, the mixture was placed in a dry round-bottom flask, and chloroform was added to the round-bottom flask to obtain a mixed solution, which was then placed on a magnetic stirrer and reacted at room temperature for 24 hours. After the reaction was completed, the reaction was stopped in an ice water bath, and the solvent was removed by a rotary evaporator to obtain a solid, which was washed and dialyzed in deionized water for 24 hours using a dialysis bag, and dried to obtain PEG2000-TPP;

[0016] (3) The DSPE-TK-COOH, PEG2000-TPP and DMAP, EDCI prepared in the first two steps are mixed uniformly in a molar ratio of 1-1.2:1-1.2:3-6:1-3, the mixture is placed in a dry round-bottom flask, and a chloroform / DMF mixed solvent is added to the round-bottom flask to obtain a mixed solution, which is then placed on a magnetic stirrer and reacted at room temperature for 24 hours. After the reaction is completed, the reaction is stopped in an ice water bath, and the solvent is removed by a rotary evaporator to obtain a solid, which is washed and dialyzed in deionized water for 24 hours using a dialysis bag, and dried to obtain DTPT;

[0017] Step 3: Preparation of Qu@NPs

[0018] The specific steps for preparing Qu@NPs are as follows:

[0019] Quercetin, soy lecithin, cholesterol, and DTPT are placed in a dry round-bottom flask in a mass ratio of 1-1.5:8-24:4-12:4-12, and a certain amount of chloroform / ethanol mixed solvent is added. After thorough mixing, the mixture is rotary evaporated for 2 hours to completely evaporate the solvent, cooled to room temperature, hydrated with deionized water, and an appropriate amount of perfluorooctyl bromide is added. After complete hydration, a cell disruptor is used for ultrasonic shearing treatment to break larger particles into small nanoparticles, and finally ROS-sensitive liposome nanoparticles for mitochondrial delivery of quercetin are obtained.

[0020] The aforementioned method for preparing Qu@NPs is characterized in that, in step 1, the molar ratio of 3-mercaptopropionic acid to anhydrous acetone is 1:2.

[0021] The aforementioned method for preparing Qu@NPs is characterized in that, in step 1, the molar ratio of trifluoroacetic acid to 3-mercaptopropionic acid is 1:2-10.

[0022] The aforementioned method for preparing Qu@NPs is characterized in that, in step 2, the ratio of chloroform to DMF is 9:1, v / v.

[0023] The aforementioned method for preparing Qu@NPs is characterized in that, in step 2, the ratio of the solvent to the mixture is 1:9, g / ml.

[0024] The aforementioned method for preparing Qu@NPs is characterized in that, in step 3, the ratio of chloroform to ethanol is 8:2, v / v.

[0025] The aforementioned method for preparing Qu@NPs is characterized in that, in step 3, the ratio of the mixture to the solvent is 1:3, mg / ml.

[0026] A method for preparing Qu@NPs, characterized in that the Qu@NPs are prepared by the aforementioned method, and the ROS-sensitive liposome nanoparticles for mitochondrial delivery of quercetin are mainly used to treat PM2.5-induced mitochondrial dysfunction.

[0027] The present invention is beneficial in that:

[0028] (1) The present invention uses synthetic functional liposomes, soybean lecithin and cholesterol in an appropriate ratio as the liposome shell, effectively achieving the drug loading of the lipophilic drug quercetin, and improving the solubility and bioavailability of quercetin;

[0029] (2) The present invention encapsulates quercetin with a lipophilic material, thereby improving the cell membrane penetration ability, prolonging the quercetin metabolism time, and reducing the peak and valley phenomenon of direct administration;

[0030] (3) The present invention introduces the mitochondrial targeting group TPP-COOH and the ROS sensitive group TK-COOH to selectively enrich quercetin inside the mitochondria, selectively control the release of quercetin in the ROS environment, enhance the ability of quercetin to resist mitochondrial dysfunction, reduce the dosage of quercetin, and eliminate the toxic side effects of systemic administration;

[0031] (4) The Qu@NPs prepared by the present invention can effectively enter the interior of mitochondria and inhibit the increase of ROS levels and the decrease of mitochondrial membrane potential induced by PM2.5. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is the synthetic route map of the ROS-responsive group TK-COOH;

[0033] Figure 2 is the 1H-NMR spectrum of the ROS-responsive group TK-COOH;

[0034] Figure 3 is the infrared spectrum of the ROS-responsive group TK-COOH;

[0035] Figure 4 is a synthetic roadmap for mitochondria-targeted, ROS-sensitive liposomes;

[0036] Figure 5(a) and Figure 5(b) are 1H-NMR and 13C-NMR images of mitochondria-targeted and ROS-sensitive liposomes, respectively;

[0037] Figure 6 is the infrared spectrum of mitochondria-targeted, ROS-sensitive liposomes;

[0038] Figure 7 is the infrared spectrum of mitochondria-targeted, ROS-sensitive liposome-loaded quercetin;

[0039] Figure 8(a), Figure 8(b), and Figure 8(c) are the particle size, potential, and TEM images of Qu@NPs, respectively;

[0040] Fig. 9 is the in vitro release profile of Qu@NPs;

[0041] Fig.10 It is the detection diagram of intracellular ROS level;

[0042] Fig.11 It is a detection diagram of mitochondrial membrane potential level;

[0043] Fig.12 This is the diagram of cell uptake of Qu@NPs.

[0044] Specific implementation examples

[0045] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0046] Part I: Preparation of Qu@NPs

[0047] Reagents: DSPE, PEG2000, 3-mercaptopropionic acid, 4-dimethylaminopyridine (DMAP), 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDCI), trifluoroacetic acid, sodium carbonate, (3-propylcarboxyl) triphenylphosphine bromide (TPP-COOH), acetone, petroleum ether, anhydrous ethanol, chloroform, soybean lecithin (DPPC), cholesterol, quercetin, DIR fluorescent dye, DMEM medium, fetal bovine serum, DCFH-DA, MitoSOX TM Mitochondrial superoxide indicator, PM2.5, MTT, Mito-Tracker Green, Mito-Tracker Red CMXRos

[0048] The preparation method of Qu@NPs, the specific steps are as follows: Step 1, synthesis of ROS sensitive bonds

[0049] Reference Figure 1 , ROS response element TK-COOH, the steps for synthesizing TK-COOH are as follows:

[0050] (1) Slowly drop 2 g of 3-mercaptopropionic acid into 4.37 g of pre-cooled anhydrous acetone and mix well;

[0051] (2) Slowly drop 0.43 g of trifluoroacetic acid into the above mixed solvent, place on a magnetic stirrer, and continue stirring the reaction for 12 h after returning to room temperature;

[0052] (3) After the reaction was completed, the mixture was placed on ice until it was completely crystallized to quench the reaction, and the precipitate was filtered out, washed with cold n-hexane and ice water, and dried to obtain TK-COOH (3.54 g, yield 74.5%) as a white solid powder. The structure of the white solid powder was characterized by 1H-NMR and infrared spectroscopy. The results are shown in Figure 2 and Figure 3 , Figure 2 and Figure 3 It shows that TK-COOH was successfully synthesized.

[0053] Step 2: Synthesis of mitochondria-targeted, ROS-sensitive liposomes

[0054] Reference Figure 4 The mitochondria-targeted, ROS-sensitive liposome is DTPT. The steps for synthesizing DTPT are as follows:

[0055] (1) TK-COOH, DSPE, DMAP and EDCI (43 mg, 184 mg, 15 mg, 230 mg) were mixed and placed in a dry round-bottom flask. 5 ml of chloroform / DMF mixed solvent was added to the round-bottom flask to obtain a mixed solution, which was then placed on a magnetic stirrer and reacted at room temperature for 24 h. After the reaction was completed, the reaction was stopped in an ice-water bath. The solvent was removed by a rotary evaporator to obtain a solid, which was washed and dialyzed in deionized water for 24 h using a dialysis bag and dried to obtain DSPE-TK-COOH (115.3 mg, yield 68.9%). ); (2) TPP-COOH, PEG2000, DMAP and EDCI (94 mg, 400 mg, 15 mg, 230 mg) were respectively mixed and placed in a dry round-bottom flask, and 5 ml of chloroform was added to the round-bottom flask to obtain a mixed solution, which was then placed on a magnetic stirrer and reacted at room temperature for 24 h. After the reaction was completed, the reaction was stopped in an ice-water bath, and the solvent was removed by a rotary evaporator to obtain a solid, which was washed and dialyzed in deionized water for 24 h using a dialysis bag and dried to obtain PEG2000-TPP (309.29 mg, yield 59.1%);

[0056] (3) DSPE-TK-COOH, PEG2000-TPP and DMAP, EDCI (100 mg, 244 mg, 7 mg, 115 mg) prepared in the first two steps were mixed evenly, and the mixture was placed in a dry round-bottom flask, and 5 ml of chloroform / DMF mixed solvent was added to the round-bottom flask to obtain a mixed solution, which was then placed on a magnetic stirrer and reacted at room temperature for 24 h. After the reaction was completed, the reaction was stopped in an ice-water bath, and the solvent was removed by a rotary evaporator to obtain a solid, which was washed and dialyzed in deionized water for 24 h using a dialysis bag, and dried to obtain DTPT (212.3 mg, yield 62.3%);

[0057] The structure of the white solid powder was characterized by 1H-NMR, 13C-NMR and infrared spectroscopy. The results are shown in Figures 5 and Figure 6 , Figure 5 and Figure 6 This indicates that DTPT was successfully synthesized.

[0058] Step 3: Preparation of Qu@NPs

[0059] The specific steps for preparing Qu@NPs are as follows:

[0060] Quercetin, soy lecithin, cholesterol, and DTPT (1 mg, 12 mg, 4 mg, and 4 mg) were placed in a dry round-bottom flask, and 9 ml of chloroform / ethanol mixed solvent was added. After thorough mixing, the mixture was rotary evaporated for 2 h to completely evaporate the solvent, cooled to room temperature, and hydrated with deionized water. An appropriate amount of perfluorooctane bromide was added. After the hydration was complete, a cell disruptor was used for ultrasonic shearing to break the larger particles into small nanoparticles, and finally Qu@NPs were obtained. Part II: Characterization of ROS-sensitive liposomal nanoparticles for mitochondrial delivery of quercetin

[0061] 1. Particle size, potential and TEM detection

[0062] The loading status of quercetin in Qu@NPs prepared in the first part was detected by infrared spectrometer.

[0063] The particle size and potential of Qu@NPs prepared in the first part were detected by Malvern particle size analyzer.

[0064] The morphology of the Qu@NPs prepared in the first part was detected by TEM. The results are shown in Figures 8(a), 8(b) and 8(c). As shown in Figures 8(a), 8(b) and 8(c), the Qu@NPs have a particle size of about 103 nm, a Zeta potential of -26.56 mV, a regular spherical shape, uniform size, good dispersion and high stability.

[0065] 2. In vitro release

[0066] Take 1 ml of Qu@NPs sample and put it into a dialysis bag (MWCO = 3 kDa), and then put it into 100 ml of release medium containing 10 μM and 100 μM H2O2. After 0, 1, 3, 5, 7 and 9 hours of reaction, take out 1 ml of solution and add 1 ml of fresh release medium, measure the quercetin concentration, and calculate the ROS-triggered drug release rate. At the same time, in order to explore whether the ROS response key TK plays a role, the same experiment was performed using Qu@NPs without TK. The in vitro release results are shown in Fig. 9 .Depend on Fig. 9It can be seen that the release rate of Qu@NPs in the release medium containing 100μM H2O2 is significantly faster, and the release rate of Qu@NPs in the release medium containing 100μM H2O2 is the fastest in the first 5 hours, indicating that Qu@NPs can release a large amount of quercetin in a short time to clear ROS in a high concentration ROS environment; by comparing the release rate of Qu@NPs without TK in the release medium containing 100μM H2O2, it can be found that Qu@NPs without TK can basically not effectively release ROS in a high concentration ROS environment, indicating that Qu@NPs in the release medium containing H2O2 mainly depends on the action of the ROS response bond TK, and this action increases with the increase of the concentration of H2O2 in the release medium. The experiment shows that TK has good ROS response characteristics.

[0067] Part III: Qu@NPs against PM2.5-induced mitochondrial dysfunction

[0068] 1. Detection of intracellular ROS levels

[0069] The intracellular ROS level was detected using the fluorescent probe dichlorodihydrofluorescein diacetate (DCFH-DA), which is suitable for both adherent and suspended cells. Therefore, it is also suitable for the adherent BEAS-2B cells used in this study. The cells were seeded in a 96-well plate at a density of 1×104cells / well and exposed to PM2.5 for 12h. The cells were then observed to have regular morphology, adherence, and good condition, and then subjected to different treatments. After treatment, the cell culture medium was carefully aspirated and serum-free medium with 10μM DCFH-DA was added to each well according to the manufacturer's instructions. Subsequently, the cells were incubated in a 37°C, 5% CO2 incubator for 20min. After washing three times with phosphate buffered saline (PBS), the excess DCFH-DA was removed and the fluorescence intensity was measured using a multifunctional microplate reader with an excitation wavelength of 485nm and an emission wavelength of 530nm, respectively. Qu@NPs, PM2.5, and cells were co-cultured to detect the scavenging ability of quercetin on intracellular ROS.

[0070] The results of intracellular ROS level detection are shown in Fig.10 .Depend on Fig.10 It can be seen that after treating cells with PM2.5 and Qu@NPs, it was found that PM2.5 induced an increase in ROS levels in Beas-2b cells in a dose-dependent manner. When PM2.5-induced model cells were treated with Qu@NPs, it was found that NPs without quercetin had almost no effect on the intracellular ROS level. As the quercetin concentration increased, the ROS level gradually decreased, indicating that Qu@NPs effectively reduced the increase in ROS levels induced by PM2.5 in cells.

[0071] 2. Mitochondrial membrane potential detection

[0072] Cells were seeded in 96-well plates at a density of 1×105 cells / mL. After different treatments, cells were washed twice with PBS / HBSS and then incubated with Mito-Tracker Red CMXRos at 37°C for 30 min. After washing with PBS / HBSS to remove free fluorescent probes, the fluorescence intensity was detected. (Red, Ex / Em: 579 / 599).

[0073] The results of mitochondrial membrane potential detection are shown in Fig.11 .Depend on Fig.11 It can be seen that: Experimental studies have found that PM2.5 induces a decrease in the membrane potential of BEAS-2B cell mitochondria in a dose-dependent manner, and 200μg / ml PM2.5 can significantly reduce mitochondrial membrane potential. After treatment with 40μg / ml Qu@NPs, this trend was effectively reversed, significantly increasing the mitochondrial membrane potential. This shows that Qu@NPs can effectively improve PM2.5-induced mitochondrial dysfunction.

[0074] 3. Mitochondrial colocalization

[0075] The cells were seeded into a laser confocal culture dish at 5×104 cells / well to 1×105 cells / well, cultured for 24 hours, and then treated with liposomes containing DIR for 3-6 hours. After the treatment, the culture medium was carefully aspirated, and the culture medium containing the above markers was added, incubated for 20 minutes, and then washed three times with PBS and observed under a laser confocal microscope (Mito-Tracker Green has a maximum excitation of 490 nm, a maximum emission of 516 nm, and green fluorescence; Dir has a maximum excitation of 748 nm, a maximum emission of 780 nm, and deep red fluorescence)

[0076] The results of mitochondrial colocalization detection are shown in Fig.12 .Depend on Fig.12 It can be seen that Qu@NPs can effectively enter the mitochondria to exert their effects, and with the increase of time, the ability of mitochondrial targeting continues to increase.

[0077] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of various changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for preparing ROS-sensitive liposome nanoparticles (Qu@NPs) for mitochondrial delivery of quercetin, characterized in that: The following steps are involved: Step 1: Synthesize ROS-sensitive bonds The ROS response element is propane-2,2-diylbis(thio)]diacetic acid (TK-COOH). The steps for synthesizing TK-COOH are as follows: (1) Slowly drip an appropriate amount of 3-mercaptopropionic acid into a round-bottom flask filled with excess anhydrous acetone and place it in an ice-water bath; (2) Slowly drop an appropriate amount of trifluoroacetic acid into the round-bottom flask, place the mixture on a magnetic stirrer, and continue stirring the mixture for 12 h after returning to room temperature; (3) After the reaction is completed, the mixture is placed on ice until it is completely crystallized to quench the reaction, and the precipitate is filtered out, washed with cold n-hexane and ice water, and dried to obtain TK-COOH; Step 2: Synthesis of mitochondria-targeted, ROS-sensitive liposomes The mitochondria-targeted, ROS-sensitive liposome is DSPE-TK-PEG2000-TPP (DTPT). The steps for synthesizing DTPT are as follows: (1) TK-COOH, distearoylphosphatidylethanolamine (DSPE), 4-dimethylaminopyridine (DMAP) and 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDCI) are mixed uniformly in a molar ratio of 1-1.2:1:3-6:1-3, the mixture is placed in a dry round-bottom flask, and a chloroform / DMF mixed solvent is added to the round-bottom flask to obtain a mixed solution, which is then placed on a magnetic stirrer and reacted at room temperature for 24 hours. After the reaction is completed, the reaction is stopped in an ice water bath, and the solvent is removed by a rotary evaporator to obtain a solid, which is washed and dialyzed in deionized water for 24 hours using a dialysis bag, and dried to obtain DSPE-TK-COOH; (2) (3-propylcarboxyl) triphenylphosphine bromide (TPP-COOH), polyethylene glycol-2000 (PEG2000), DMAP and EDCI are mixed uniformly in a molar ratio of 1-1.2:1:3-6:1-3, the mixture is placed in a dry round-bottom flask, and chloroform is added to the round-bottom flask to obtain a mixed solution, which is then placed on a magnetic stirrer and reacted at room temperature for 24 hours. After the reaction is completed, the reaction is stopped in an ice water bath, and the solvent is removed by a rotary evaporator to obtain a solid, which is washed and dialyzed in deionized water for 24 hours using a dialysis bag, and dried to obtain PEG2000-TPP; (3) The DSPE-TK-COOH, PEG2000-TPP and DMAP, EDCI prepared in the first two steps are mixed uniformly in a molar ratio of 1-1.2:1-1.2:3-6:1-3, the mixture is placed in a dry round-bottom flask, and a chloroform / DMF mixed solvent is added to the round-bottom flask to obtain a mixed solution, which is then placed on a magnetic stirrer and reacted at room temperature for 24 hours. After the reaction is completed, the reaction is stopped in an ice water bath, and the solvent is removed by a rotary evaporator to obtain a solid, which is washed and dialyzed in deionized water for 24 hours using a dialysis bag, and dried to obtain DTPT; Step 3: Preparation of Qu@NPs The specific steps for preparing Qu@NPs are as follows: Quercetin, soy lecithin, cholesterol, and DTPT were placed in a dry round-bottom flask in a mass ratio of 1-1.5:8-24:4-12:4-12, and a certain amount of chloroform / ethanol mixed solvent was added. After thorough mixing, the mixture was rotary evaporated for 2 hours to completely evaporate the solvent. The mixture was cooled to room temperature, deionized water was added for hydration, and an appropriate amount of perfluorooctyl bromide was added. After complete hydration, a cell disruptor was used for ultrasonic shearing treatment to break larger particles into small nanoparticles to finally obtain Qu@NPs.

2. The method for preparing Qu@NPs according to claim 1, characterized in that: In step 1, the molar ratio of 3-mercaptopropionic acid to anhydrous acetone is 1:

2.

3. The method for preparing Qu@NPs according to claim 1, characterized in that: In the first step, the molar ratio of trifluoroacetic acid to 3-mercaptopropionic acid is 1:2-10.

4. The method for preparing Qu@NPs according to claim 1, characterized in that: In step 2, the ratio of chloroform to DMF was 9:1, v / v.

5. The method for preparing Qu@NPs according to claim 1, characterized in that: In step 2, the ratio of solvent to mixture was 1:9, g / ml.

6. The method for preparing Qu@NPs according to claim 1, characterized in that: In step 3, the ratio of chloroform to ethanol was 8:2, v / v.

7. The method for preparing Qu@NPs according to claim 1, characterized in that: In step 3, the ratio of the mixture to the solvent was 1:3, mg / ml.

8. A Qu@NPs, characterized in that: Prepared by the method according to any one of claims 1 to 7.

9. Use of the Qu@NPs according to claim 8 in treating PM2.5-induced mitochondrial dysfunction.

10. A method for preparing Qu@NPs, characterized in that: Prepared by the method of claim 1.

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