Carbon dot capable of remarkably improving solubility and biological effect of baicalin

Abstract

The invention discloses a carbon dot capable of remarkably improving the solubility and the biological effect of baicalin, and belongs to the technical field of medicines. The invention relates to application of scutellaria baicalensis carbon dots (nano particles / particles / nano components), the carbon dots can obviously increase the solubility of baicalin in water, and the application comprises the biological effects of improving the solubility and bioavailability of the baicalin in water, resisting inflammation and oxidation, resisting tumors and the like.

Description

Technical Field

[0001] The present invention relates to the medical field, and in particular to a new application of scutellaria baicalensis carbon dots in the medical field. Background Art

[0002] Baicalin is one of the active ingredients in Scutellaria baicalensis, and has a wide range of pharmacological effects, such as anti-tumor, anti-inflammatory, antihypertensive, sedative, liver-protective, choleretic, antibacterial, anti-pathogen, anti-cerebral ischemic injury, anti-allergic, improving diabetic nephropathy, improving retinopathy, etc. Baicalin is a flavonoid compound with particularly low water solubility and bioavailability. It is reported that after oral administration of baicalin to rats, its complete bioavailability is 2.2%, and the bioavailability of intravenous baicalin is 4.8%. Therefore, its more effective service in clinical practice is greatly limited.

[0003] The present invention discovered that the scutellaria baicalensis carbon dots have good water solubility, a particle size of less than 10 nm, and are mainly composed of elements such as carbon, hydrogen, and oxygen. They can greatly improve the solubility of baicalin in water, and as the concentration of the carbon dots increases, the solubility-aiding effect is significantly enhanced. This discovery has opened up a new way to solve the solubility problem of baicalin. Summary of the invention

[0004] The present invention relates to carbon dots (nanoparticles / nanoparticles / nano-like components) extracted and separated from scutellaria baicalensis charcoal, referred to as RSC-CDs or RSC-NPs. The carbon dots can significantly increase the solubility of baicalin in water, and the applications thereof include improving the solubility, bioavailability, anti-inflammatory, antioxidant and anti-tumor biological effects of baicalin.

[0005] The invention provides a new application of scutellaria baicalensis carbon dots. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 .Electron microscopy characterization of RSC-CDs, Figure 1 a: HRTEM image; Figure 1 b: TEM image; Figure 1 c: Particle size distribution histogram.

[0007] Figure 2 .X-ray photoelectron spectroscopy (XPS) analysis of RSC-CDs, Figure 2 A: XPS panorama; Figure 2 B: C 1s high-resolution image; Figure 2 C: O 1s high-resolution image.

[0008] Figure 3 .Effects on LPS-induced inflammatory factors in RAW264.7, Figure 3 A: TNF-α; Figure 3 B: IL-1β; Figure 3C: IL-6.

[0009] Figure 4 .Effects on LPS-induced oxidative stress factors in RAW264.7 cells, Figure 4 A: MDA; Figure 4 B: SOD; Figure 4 C: GSH.

[0010] Figure 5 .Tumor size and tumor inhibition rate in mice, Figure 5 A: Tumor size of H22-induced liver cancer mice; Figure 5 B: tumor inhibition rate; Figure 5 C: Tumor weight. DETAILED DESCRIPTION

[0011] The technical solution of the present invention will be clearly and completely described below in conjunction with specific embodiments, but the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0012] Example 1: Extraction, purification and characterization of Scutellaria baicalensis carbon dots

[0013] The charcoal of Scutellaria baicalensis was crushed and decocted twice with water, each time for 2 hours. The decoctions were combined and first coarsely filtered through a Buchner funnel and then finely filtered through a 0.22μm microporous filter membrane. The filtrate was concentrated to 1g / mL, loaded into a 1000Da dialysis membrane, and dialyzed with water until small molecular compounds such as baicalin were no longer detected in the dialysis fluid. The dialysis fluid in the bag containing RSC-CDs was taken out and freeze-dried into powder to obtain RSC-CDs.

[0014] The RSC-CDs were characterized by transmission electron microscopy and X-ray photoelectron spectroscopy (XPS). Figure 1 and Figure 2 .

[0015] Example 2: Scutellaria baicalensis carbon dots improve the solubility of baicalin

[0016] In order to investigate whether RSC-CDs can improve the solubility of baicalin (BAL), direct heating method, ultrasonic method and stirring method were used to study it.

[0017] First, excess BAL is transferred to the RSC-CDs solution to form a supersaturated solution of BAL, and then the following treatments are performed:

[0018] (1) Direct heating method: Place the above supersaturated solution in an oven and heat at 100°C for 2 hours.

[0019] (2) Ultrasonic method: The supersaturated solution was subjected to ultrasonic treatment in an ice bath (99 Hz, 10 min).

[0020] (3) Stirring method: Stir the supersaturated solution on a magnetic stirrer for 48 h.

[0021] The suspension obtained after the treatments (1), (2) and (3) was then centrifuged at 4000 rpm for 20 min to obtain the supernatant, which was filtered through a 0.22 μm microporous filter membrane and then analyzed by HPLC.

[0022] The results showed that among the three methods, direct heating method had the greatest effect on promoting the solubility of BAL. When the initial concentration of RSC-CDs was 450 μg / mL, direct heating made the solubility of BAL in RSC-CDs solution reach 124.24 μg / mL, which was significantly better than the solubilization effect of BAL by ultrasound method (CBAL: 103.71 μg / mL) and high-speed mixing and stirring method (CBAL: 71.12 μg / mL).

[0023] The concentration of pure BAL saturated solution is about 1 μg / mL, so RSC-CDs solution can significantly improve the solubility of BAL, and direct heating method has the best effect.

[0024] Example 3. Scutellaria baicalensis carbon dots improve the bioavailability of baicalin

[0025] RSC-CDs / BAL complex was prepared by direct heating method and given to Kunming mice by gavage. The control group was gavaged with the same amount of BAL suspension. Blood samples were collected at 10min, 20min, 30min, 45min, 60min, 120min, 240min, 360min, and 480min after administration to detect the content of BAL. The time-blood concentration pharmacokinetic curve was drawn, and the results showed that RSC-CDs significantly increased the area under the blood concentration-time curve of BAL, thereby improving the bioavailability of baicalin.

[0026] Example 4: Scutellaria baicalensis carbon dots enhance the anti-inflammatory and antioxidant effects of baicalin

[0027] RAW 264.7 cells differentiated after LPS stimulation, and the differentiated cells produced a large amount of toxic mediators, such as IL-1β, TNF-α, and IL-6. In this study, the levels of inflammatory factors in the cell supernatant were detected to examine the anti-inflammatory effect of RSC-NPs on BAL.

[0028] In this experiment, a control group, a model group, and a drug treatment group were set up. The control group was cultured with normal culture medium; the model group was added with LPS at a final concentration of 1 μg / mL; the drug group was pretreated for 2 hours before adding LPS; after 24 hours of drug treatment, the supernatant was taken and the ELISA method was used to determine the levels of IL-1β, TNF-α, and IL-6. Figure 3 The results showed that the inhibitory effect of the RSC-NPs / BAL complex group on TNF-α, IL-1β and IL-6 was better than that of BAL and RSC-NPs at the same dose.

[0029] The process of inflammatory response is often accompanied by oxidative stress. When the body is under oxidative stress, a large amount of MDA will be produced and the content or enzyme activity of oxygen free radical scavengers such as SOD and GSH will be inhibited, eventually leading to cellular oxidative damage. Therefore, this study selected three classic indicators, SOD, GSH and MDA, to explore the effect of the RSC-NPs / BAL complex formed after RSC-NPs solubilized BAL on the antioxidant effect of BAL. The above cell supernatants were taken to detect MDA, SOD and GSH, and the results are shown in Figure 4 , the antioxidant effect of RSC-NPs / BAL complex is better than that of BAL and RSC-NPs at the same dose.

[0030] Example 5: Scutellaria baicalensis carbon dots enhance the anti-tumor effect of baicalin

[0031] In this study, an animal model of liver cancer was established by subcutaneously injecting H22 cells into mice. Mice with tumors the size of rice grains were screened and regrouped on the 7th day after tumor bearing, and drug intervention was performed to compare the anti-tumor effects of RSC-CDs, BAL, RSC-CDs / AL complex, and RSC-CDs and BAL physical mixture. The net body weight of each group of animals was weighed on the 7th day after tumor bearing. The results showed that ( Figure 5 B), compared with the control group, the net body weight of the model group mice after tumor-bearing was significantly reduced, and there was a significant difference between the data and the control group (P < 0.01). Cyclophosphamide, RSC-CDs, BAL, RSC-CDs / BAL complex, and RSC-CDs and BAL physical mixture can alleviate the phenomenon of net body weight loss in tumor-bearing mice to a certain extent after intervention, among which the net body weight of the animals in the RSC-CDs / BAL complex intervention group was statistically different from that of the model group (P < 0.05). The above research results show that compared with RSC-CDs, BAL, and RSC-CDs and BAL physical mixture, RSC-CDs / BAL complex showed better efficacy in alleviating the net body weight loss of tumor-bearing mice.

[0032] The tumors of each group of animals were further weighed and photographed, and the inhibition rate of drug intervention on liver cancer mouse tumors was calculated. The specific results are as follows: Figure 5shown. Figure 5 A shows that compared with the model group, the positive drug cyclophosphamide, BAL and SRC-CDs / BAL complex intervention can reduce the tumor size of liver cancer mice, and the above three drugs can significantly reduce the tumor weight of liver cancer mice ( Figure 5 B; positive drug, SRC-CDs / BAL complex: P < 0.01; BAL: P < 0.05), the tumor inhibition rates can reach 54.2%, 34.5% and 40.0%, respectively ( Figure 5 C). It is worth noting that the SRC-CDs / BAL complex showed a stronger anti-tumor effect compared with the BAL group animals. In addition, the physical mixture of SRC-CDs and BAL can also reduce the tumor size and mass of liver cancer mice to a certain extent after intervention, but the statistical difference is not significant compared with the data of the model group animals. When SRC-CDs were administered alone, the tumor inhibition effect on liver cancer mice was not obvious. The above results show that SRC-CDs have the potential to serve as BAL nano-delivery carriers, thereby enhancing the anti-tumor effect of BAL.

[0033] Example 6: Purification of baicalin using scutellaria baicalensis carbon dots

[0034] Take Scutellaria baicalensis, add water and boil twice, each time for 2 hours, filter, combine the filtrate, add appropriate amount of Scutellaria baicalensis carbon dots, heat at 100°C for 2 hours, filter through 0.22μm microporous filter membrane or centrifuge at 5000r / min for 30min, take the filtrate or supernatant, concentrate to a certain volume, dialyze or ultrafilter with a dialysis bag, collect the solution outside the dialysis bag or the solution outside the ultrafiltration tube, concentrate and dry to obtain high-purity baicalin (purity>60%).

Claims

1. Application of Scutellaria baicalensis carbon dots in the medical field.

2. The use of the scutellaria baicalensis carbon dots according to claim 1, characterized in that Increase the solubility of baicalin.

3. The use of the scutellaria baicalensis carbon dots according to claim 2, characterized in that The application of Scutellaria baicalensis carbon dots can improve the solubility, bioavailability, anti-inflammatory, antioxidant, anti-tumor and other biological effects of baicalin in water, and can also be used to prepare high-purity baicalin.

4. The use according to any one of claims 1 to 3, characterized in that: The scutellaria baicalensis carbon dots and baicalin are prepared into clinical preparations with pharmaceutically acceptable auxiliary materials.

5. The use according to any one of claims 1 to 3, characterized in that: The clinical preparations include, but are not limited to, injections, oral liquid preparations, hard capsules, soft capsules, tablets, suppositories, water pills, honey pills, concentrated pills, ointments, powders, emulsions, pastes, and smears.

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