Carbon quantum dot as well as preparation method and application thereof

Abstract

The invention relates to the technical field of carbon quantum dot processing, in particular to a carbon quantum dot and a preparation method and application thereof. The invention provides a carbon quantum dot. The carbon quantum dot is prepared from an original prescription and / or decoction dregs of a lung-ventilating and turbidity-eliminating prescription. The original prescription of the lung-ventilating and turbidity-eliminating prescription comprises the following components in parts by mass: honey-fried ephedra, fructus forsythiae, gypsum, rhizoma pinellinae praeparata, rhizoma atractylodis, pogostemon cablin, wine-treated rhubarb, pericarpium citri reticulatae, almond, mint, platycodon grandiflorum, rhizoma phragmitis, radix paeoniae rubra and liquorice. The carbon quantum dots are prepared on the basis of the prescription of diffusing lung and eliminating turbidity, the vacancy of preparing the carbon quantum dots from single traditional Chinese medicinal materials in the prior art is made up, the carbon quantum dots are prepared from medicine residues on the basis, and the utilization rate of the medicinal materials is increased; the carbon quantum dots prepared by using the lung-ventilating and turbidity-eliminating formula have a bacteriostatic effect and a remarkable effect.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon quantum dot processing, and particularly to a carbon quantum dot, a preparation method thereof, and an application thereof. Background Art

[0002] As a class of emerging nanomaterials (less than 10 nm), carbon quantum dots (CDs) are metal-free nanoscale positively charged quantum dots with strong fluorescence properties and certain antibacterial and antiviral potentials. They interact electrostatically with cells to exert antibacterial and antiviral effects. This material not only overcomes the disadvantages of low biocompatibility of traditional organic dyes and metal-based nanomaterials, but also has many advantages such as optical stability and low preparation cost, and has been widely used in medicine, bioimaging, sensing, electronic devices, and catalysis, especially in the antibacterial and antiviral fields.

[0003] At present, there have been studies attempting to prepare various nanoscale traditional Chinese medicine substances to improve the utilization space of traditional Chinese medicine. However, in a large number of literatures and real life, there is still little research on the reuse of traditional Chinese medicine residues. Currently, the residues of traditional Chinese medicine prescriptions are still mainly treated as waste through stacking and incineration, which not only causes waste of resources and environmental burden, but also is not conducive to sustainable development. Summary of the Invention

[0004] The purpose of the present invention is to provide a carbon quantum dot prepared from the original prescription and / or residues of the Xuanfei Paizhuo Prescription, and a preparation method thereof, and the carbon quantum dot has antibacterial effects.

[0005] In order to achieve the above-mentioned invention purpose, the present invention provides the following technical solutions:

[0006] The present invention provides a carbon quantum dot, which is prepared from the original prescription and / or residues of the Xuanfei Paizhuo Prescription;

[0007] The original prescription of the Xuanfei Paizhuo Prescription includes the following components in parts by mass: 5 - 7 parts of honey-fried Ephedra, 14 - 16 parts of Forsythia suspensa, 29 - 31 parts of raw Gypsum Fibrosum, 8 - 10 parts of Pinellia ternata processed with Rhizoma Zingiberis Recens, 11 - 13 parts of Atractylodes lancea, 5 - 7 parts of Pogostemon cablin, 5 - 7 parts of Rheum officinale processed with wine, 5 - 7 parts of Citrus reticulata Blanco, 5 - 7 parts of Armeniaca vulgaris var. ansu, 8 - 10 parts of Mentha haplocalyx Briq., 5 - 7 parts of Platycodon grandiflorus, 14 - 16 parts of Phragmites communis Trin., 11 - 13 parts of Paeonia lactiflora Pall., and 2 - 4 parts of Glycyrrhiza uralensis Fisch.

[0008] The present invention also provides a preparation method of the carbon quantum dot, including the following steps:

[0009] (1) Crushing the original prescription and / or residues of the Xuanfei Paizhuo Prescription to obtain traditional Chinese medicine powder;

[0010] (2) Mixing the traditional Chinese medicine powder with water to obtain a mixture; subjecting the mixture to hydrothermal reaction for 5 - 7 h to obtain a reacted solution;

[0011] (3) Centrifuge, ultrafilter, and concentrate the solution after the reaction to obtain carbon quantum dots;

[0012] The original prescription of the formula for dispersing lung qi and expelling turbidity is the original prescription of the formula for dispersing lung qi and expelling turbidity as described.

[0013] Preferably, the particle size of the traditional Chinese medicine powder is 70-90 mesh.

[0014] Preferably, the mass-to-volume ratio of the traditional Chinese medicine powder to water is 1 g: 50-70 ml.

[0015] Preferably, the temperature of the hydrothermal reaction is 150-200 °C; the pressure of the hydrothermal reaction is 2.0-3.0 MPa.

[0016] Preferably, the rotation speed of the centrifugation is 5500-6500 r / min; the time of the centrifugation is 25-35 min;

[0017] The ultrafiltration is membrane filtration;

[0018] The pore size of the membrane is 0.40-0.50 μm; the concentration time is 10-14 h; the temperature of the concentration is 90-99 °C.

[0019] The present invention also provides the application of the carbon quantum dots as described in the preparation of antibacterial products.

[0020] Preferably, the bacteria to be inhibited are bacteria; the bacteria include Escherichia coli and Staphylococcus aureus.

[0021] The present invention also provides the application of the carbon quantum dots prepared by the preparation method as described in the preparation of antibacterial products.

[0022] Preferably, the bacteria to be inhibited are bacteria; the bacteria include Escherichia coli and Staphylococcus aureus.

[0023] Advantages of the present invention:

[0024] The present invention prepares carbon quantum dots based on the formula of "the formula for dispersing lung qi and expelling turbidity", making up for the gap in the prior art of using a single traditional Chinese medicine material to prepare carbon quantum dots, and on this basis, using the medicinal residues to prepare carbon quantum dots, improving the utilization rate of the medicinal materials;

[0025] The carbon quantum dots prepared by the present invention using the "formula for dispersing lung qi and expelling turbidity" have antibacterial effects and significant effects. Description of the drawings

[0026] Figure 1 It is the infrared spectrum diagram of the carbon quantum dots described in Examples 1-3;

[0027] Figure 2 The infrared spectrogram of the carbon quantum dots described in Examples 4 to 6;

[0028] Figure 3 The inhibitory effect of the carbon quantum dots described in Examples 1 to 3 on Escherichia coli;

[0029] Figure 4 The inhibitory effect of the carbon quantum dots described in Examples 1 to 3 on Staphylococcus aureus;

[0030] Figure 5 The inhibitory effect of the carbon quantum dots described in Examples 4 to 6 on Escherichia coli;

[0031] Figure 6 The inhibitory effect of the carbon quantum dots described in Examples 4 to 6 on Staphylococcus aureus;

[0032] Figure 7 The environmental antibacterial effect of the carbon quantum dots described in Example 1 and Example 6. Detailed implementation manners

[0033] The present invention provides a kind of carbon quantum dots, which are prepared from the original prescription and / or medicinal residues of the formula for dispersing turbid substances by diffusing the lung;

[0034] The original prescription of the formula for dispersing turbid substances by diffusing the lung includes the following components in parts by mass:

[0035] Honey-fried Ephedra 5 - 7 parts, preferably 6 parts;

[0036] Forsythia suspensa 14 - 16 parts, preferably 15 parts;

[0037] Gypsum fibrosum 29 - 31 parts, preferably 30 parts;

[0038] Pinellia ternata 8 - 10 parts, preferably 9 parts;

[0039] Atractylodes lancea 11 - 13 parts, preferably 12 parts;

[0040] Patchouli 5 - 7 parts, preferably 6 parts;

[0041] Wine-processed Rheum officinale 5 - 7 parts, preferably 6 parts;

[0042] Tangerine peel 5 - 7 parts, preferably 6 parts;

[0043] Apricot kernel 5 - 7 parts, preferably 6 parts;

[0044] Mentha haplocalyx 8 - 10 parts, preferably 9 parts;

[0045] Platycodon grandiflorum 5 - 7 parts, preferably 6 parts;

[0046] Phragmites communis 14 - 16 parts, preferably 15 parts;

[0047] 11-13 parts of red peony root, preferably 12 parts;

[0048] 2 to 4 parts of licorice, preferably 3 parts.

[0049] The present invention also provides a method for preparing the carbon quantum dots, comprising the following steps:

[0050] (1) crushing the original prescription and / or the medicinal residue of Xuanfei Paizhao prescription to obtain Chinese medicinal powder;

[0051] (2) mixing the Chinese medicine powder with water to obtain a mixture; subjecting the mixture to a hydrothermal reaction for 5 to 7 hours to obtain a solution after the reaction;

[0052] (3) centrifuging, ultrafiltering, and concentrating the solution after the reaction to obtain carbon quantum dots;

[0053] The original formula of the Xuanfei Paizhuo prescription is the original formula of the Xuanfei Paizhuo prescription;

[0054] In the present invention, the particle size of the Chinese medicine powder is 70 to 90 meshes, preferably 80 meshes;

[0055] In the present invention, the method of crushing the original prescription of Xuanfei Paizhuo prescription also includes drying the original prescription of Xuanfei Paizhuo prescription; the drying temperature is 60° C., and crushing is performed when the water content is below 12%.

[0056] In the present invention, the water content is preferably 4-8%, more preferably 6%;

[0057] In the present invention, the method of crushing the residue of the Xuanfei Paizhuo prescription further comprises drying the residue of the Xuanfei Paizhuo prescription; the drying temperature is 60° C., and the residue is crushed when the moisture content is below 12%;

[0058] In the present invention, the water content is preferably 4-8%, more preferably 6%;

[0059] In the present invention, the preparation method of the medicinal residue of the Xuanfei Paizhuo prescription is as follows: soaking and decocting the original prescription of the Xuanfei Paizhuo prescription; the soaking time is 25 to 35 minutes, preferably 30 minutes; the decocting times are 1 to 3 times, preferably 2 times; the decocting time each time is 15 to 25 minutes, preferably 20 minutes;

[0060] In the present invention, the mass volume ratio of the Chinese medicine powder and water is 1g:50-70ml, preferably 1g:60ml;

[0061] In the present invention, the method of mixing the Chinese medicine powder with water is as follows: adding the Chinese medicine powder to water, magnetically stirring at 25° C. for 10 minutes, and shaking for 30 minutes;

[0062] In the present invention, the temperature of the hydrothermal reaction is 150 to 200 °C, preferably 175 °C; the pressure of the hydrothermal reaction is 2.0 to 3.0 MPa, preferably 2.5 MPa;

[0063] In the present invention, the time of the hydrothermal reaction is preferably 6 h;

[0064] In the present invention, after the hydrothermal reaction, it is necessary to first cool to 25 °C and then perform centrifugation;

[0065] In the present invention, the rotation speed of the centrifugation is 5500 to 6500 r / min, preferably 6000 r / min; the time of the centrifugation is 25 to 35 min, preferably 30 min;

[0066] The ultrafiltration is membrane filtration;

[0067] The pore size of the membrane is 0.40 to 0.50 μm, preferably 0.45 μm; the concentration time is 10 to 14 h, preferably 12 h; the temperature of the concentration is 90 to 99 °C, preferably 94.5 °C;

[0068] The present invention also provides the application of the carbon quantum dots in the preparation of antibacterial products.

[0069] In the present invention, the bacteria to be inhibited are bacteria; the bacteria include Escherichia coli and Staphylococcus aureus.

[0070] The present invention also provides the application of the carbon quantum dots prepared by the preparation method in the preparation of antibacterial products.

[0071] In the present invention, the bacteria to be inhibited are bacteria; the bacteria include Escherichia coli and Staphylococcus aureus.

[0072] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0073] Example 1

[0074] (1) Take the original prescription of "Xuanfei Paizhuo Decoction": honey-fried Ephedra 6 g, Forsythia suspensa 15 g, raw gypsum 30 g (decocted first), Pinellia ternata 9 g, Atractylodes lancea 12 g, Pogostemon cablin 6 g, rheum officinale 6 g, tangerine peel 6 g, almond 6 g, mint 9 g (added later), platycodon grandiflorum 6 g, phragmites communis 15 g, red peony root 12 g, licorice 3 g, dry at 60 °C until the water content is 10%, pulverize, and pass through an 80-mesh sieve to obtain traditional Chinese medicine powder;

[0075] (2) Take 1 g of traditional Chinese medicine powder and add it to 60 ml of water. Stir magnetically at 25 °C for 10 min, shake for 30 min, then transfer it to a reaction kettle and carry out hydrothermal reaction at 150 °C and 2.3 MPa for 6 h to obtain the reacted solution;

[0076] (3) Cool the reacted solution to 25 °C, then centrifuge at 6000 r / min for 30 min, filter through a 0.45 μm aqueous ultrafiltration membrane, and then concentrate at 99 °C in a vacuum centrifugal concentrator for 12 h to obtain carbon quantum dots.

[0077] Example 2

[0078] Referring to Example 1, change the parameters of the hydrothermal reaction to 180 °C and 2.5 MPa, and the other steps are the same as those in Example 1.

[0079] Example 3

[0080] Referring to Example 1, change the parameters of the hydrothermal reaction to 200 °C and 2.8 MPa, and the other steps are the same as those in Example 1.

[0081] Example 4

[0082] (1) Take the original formula of "Xuanfei Paizhuo Decoction" (6 g of honey-fried ephedra, 15 g of forsythia, 30 g of raw gypsum (decocted first), 9 g of pinellia ternata, 12 g of atractylodes lancea, 6 g of agastache rugosa, 6 g of rheum officinale, 6 g of tangerine peel, 6 g of apricot kernel, 9 g of mentha haplocalyx (added later), 6 g of platycodon grandiflorum, 15 g of phragmites communis, 12 g of red peony root, 3 g of licorice root), soak it in water for 30 min, heat it to boiling for 20 min, change the liquid and then heat it again, dry it at 60 °C until the water content is 10%, pulverize it, and sieve it through an 80-mesh sieve to obtain traditional Chinese medicine powder;

[0083] (2) Take 1 g of traditional Chinese medicine powder and add it to 60 ml of water. Stir magnetically at 25 °C for 10 min, shake for 30 min, then transfer it to a reaction kettle and carry out hydrothermal reaction at 150 °C and 2.3 MPa for 6 h to obtain the reacted solution;

[0084] (3) Cool the reacted solution to 25 °C, then centrifuge at 6000 r / min for 30 min, filter through a 0.45 μm aqueous ultrafiltration membrane, and then concentrate at 99 °C in a vacuum centrifugal concentrator for 12 h to obtain carbon quantum dots.

[0085] Example 5

[0086] Referring to Example 4, change the parameters of the hydrothermal reaction to 180 °C and 2.5 MPa, and the other steps are the same as those in Example 4.

[0087] Example 6

[0088] Referring to Example 4, the parameters of the hydrothermal reaction were changed to 200 °C and 2.8 MPa, and the other steps were the same as in Example 4.

[0089] Experimental Example 1 Characterization and Testing of Carbon Quantum Dots

[0090] The carbon quantum dots described in Examples 1 to 6 were measured using a Fourier transform infrared spectrometer, where the light was 400 - 4000 cm -1 , the sampling amount was 1 mg, the number of scans was 4, and the resolution was 8.

[0091] The measurement results are as Figures 1-2 shown. The infrared spectra of Examples 1 to 3 are as Figure 1 shown, where Y150 is the carbon quantum dot of Example 1, Y180 is the carbon quantum dot of Example 2, and Y200 is the carbon quantum dot of Example 3; the infrared spectra of Examples 4 to 6 are as Figure 2 shown, z150 is the carbon quantum dot of Example 4, z180 is the carbon quantum dot of Example 5, and z200 is the carbon quantum dot of Example 6.

[0092] The main functional groups of the carbon quantum dots were determined by infrared spectroscopy analysis. The main peak at 3394 cm -1 is due to OH stretching vibration or NH stretching vibration; an absorption peak appears at 2932 cm -1 due to the asymmetric stretching vibration of C=O=C; an absorption peak appears at 1622 cm -1 due to C=O stretching vibration or NH bending vibration; an absorption peak appears at 1419 cm -1 due to CN stretching vibration or in-plane bending vibration of OH; an absorption peak appears at 1154 cm -1 due to C-O-C stretching vibration; an absorption peak appears at 1031 cm -1 due to C-O stretching vibration; an absorption peak appears at 668 cm -1 due to out-of-plane bending vibration of C=O=C or OH bending vibration.

[0093] Experimental Example 2 Inhibitory Effects on Escherichia coli and Staphylococcus aureus

[0094] (1) Preparation of carbon dot solution: Carbon dot solutions with a concentration of 150 mg / ml were respectively prepared by taking the carbon quantum dots described in Examples 1 to 6;

[0095] (2) Preparation of bacterial solution: Weigh 0.09 g of nutrient broth and 0.15 g of tryptic soy broth, add them to 50 ml of water respectively, shake well, and perform autoclaving at 121 °C for 150 min. Then add 10 μl of Escherichia coli bacterial solution and Staphylococcus aureus bacterial solution preserved in the laboratory to them respectively in a laminar flow hood, and culture them at a rotation speed of 100 r / min and a temperature of 37 °C for 10 h;

[0096] (3) Preparation of diluent: Weigh 0.9 g of nutrient broth and 1.5 g of tryptic soy broth, add them to 50 ml of water respectively to prepare Escherichia coli diluent and Staphylococcus aureus diluent. Shake well and perform autoclaving at 121 °C for 150 min. Use the prepared diluent to dilute the Escherichia coli and Staphylococcus aureus in step (2) to obtain the diluted bacterial solution, where the diluted concentration of Escherichia coli is 1.5×10 3 CFU / ml, and the diluted concentration of Staphylococcus aureus is about 1.5×10 2 CFU / ml;

[0097] (4) Bacterial inoculation: In a laminar flow hood after 30 min of ultraviolet disinfection, use a pipette gun to aspirate 100 μl of carbon dot solution and add it to a culture medium containing 100 μl of Escherichia coli with a concentration of 1.5×10 3 CFU / ml and Staphylococcus aureus with a concentration of 5×10 2 CFU / ml, and spread it evenly. Set a control group without adding carbon dot solution. Aspirate 100 μl of the diluted bacterial solution into the culture medium, and then transfer it to an incubator and culture it at 37 °C for 24 h. Observe the growth of bacteria on the surface of the culture medium. The culture medium is ordinary agar medium (for Escherichia coli) and tryptic soy agar medium (for Staphylococcus aureus).

[0098] The results are as Figures 3-6 shown. Figure 3 The inhibitory effects of the carbon quantum dots described in Examples 1 - 3 on Escherichia coli are shown. From left to right are the control group, Example 1, Example 2, and Example 3; Figure 4 The inhibitory effects of the carbon quantum dots described in Examples 1 - 3 on Staphylococcus aureus are shown. From left to right are the control group, Example 1, Example 2, and Example 3; Figure 5 The inhibitory effects of the carbon quantum dots described in Examples 4 - 6 on Escherichia coli are shown. From left to right are the control group, Example 4, Example 5, and Example 6; Figure 6 The inhibitory effects of the carbon quantum dots described in Examples 4 - 6 on Staphylococcus aureus are shown. From left to right are the control group, Example 4, Example 5, and Example 6.

[0099] As can be seen from the figure, the carbon quantum dots described in Examples 1 to 6 have inhibitory effects on Escherichia coli and Staphylococcus aureus, and among them, the carbon quantum dots in Example 1 and Example 6 have the best antibacterial effects.

[0100] Experimental Example 3 Environmental Antibacterial Experiment

[0101] The carbon quantum dots described in Example 1 and Example 6 with the best antibacterial effects were selected for the experiment.

[0102] Alcohol was sprayed for disinfection within the area of 3 pieces of 5 cm * 5 cm (25 cm 2 ) of the curtain at the main entrance of the teaching building. Then, 1 ml of distilled water (blank control group), the carbon dot solution of the carbon quantum dots described in Example 1 (the preparation method refers to Experimental Example 2), and the carbon dot solution of the carbon quantum dots described in Example 6 (the preparation method refers to Experimental Example 2) were respectively applied within this range. Sampling was carried out after 24 h, and the sampling steps were as follows: Four ordinary nutrient agar plates were taken and marked as control, empty 3, 1503, and 2003. A sterile cotton swab was dipped in sterile physiological saline and gently wiped on the surface of the selected curtain, and then gently smeared on the surface of the corresponding marked culture medium (the control was not smeared). The culture medium was inverted and cultured in an incubator at 37 °C for 48 h, and the growth of bacteria on the surface of the culture medium was observed. The results are as Figure 7 shown.

[0103] From Figure 7 it can be seen that the carbon quantum dots described in Example 1 and Example 6 both showed antibacterial properties, and among them, the carbon quantum dots in Example 6 had the best antibacterial effect.

[0104] As can be seen from the above examples, the present invention provides a carbon quantum dot, its preparation method and application. The present invention uses the "Xuanfei Paizhuo Decoction" formula as the raw material to prepare carbon quantum dots, which makes up for the gap in the prior art of using a single traditional Chinese medicine material to prepare carbon quantum dots. On this basis, carbon quantum dots are prepared using the medicinal residues, improving the utilization rate of the medicinal materials; the carbon quantum dots prepared by the present invention using the "Xuanfei Paizhuo Decoction" have antibacterial effects and the effects are significant.

[0105] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A carbon quantum dot, It is characterized in that The carbon quantum dots are prepared from the original prescription and / or the residue of Xuanfei Paizhao prescription; The original prescription of the Xuanfei Paizhu prescription includes the following components in parts by weight: 5-7 parts of honey ephedra, 14-16 parts of forsythia, 29-31 parts of gypsum, 8-10 parts of French pinellia, 11-13 parts of atractylodes, 5-7 parts of patchouli, 5-7 parts of wine rhubarb, 5-7 parts of tangerine peel, 5-7 parts of almond, 8-10 parts of mint, 5-7 parts of platycodon, 14-16 parts of reed root, 11-13 parts of red peony root, and 2-4 parts of licorice.

2. The method for preparing carbon quantum dots according to claim 1, It is characterized in that The steps include: (1) crushing the original prescription and / or the medicinal residue of Xuanfei Paizhao prescription to obtain Chinese medicinal powder; (2) mixing the Chinese medicine powder with water to obtain a mixture; subjecting the mixture to a hydrothermal reaction for 5 to 7 hours to obtain a solution after the reaction; (3) centrifuging, ultrafiltering, and concentrating the solution after the reaction to obtain carbon quantum dots; The original formula of the Xuanfei Paizhuo prescription is the original formula of the Xuanfei Paizhuo prescription according to claim 1.

3. The preparation method according to claim 2, It is characterized in that The particle size of the traditional Chinese medicine powder is 70 to 90 meshes.

4. The preparation method according to claim 3, It is characterized in that The mass volume ratio of the traditional Chinese medicine powder and water is 1g:50-70ml.

5. The preparation method according to claim 4, It is characterized in that The temperature of the hydrothermal reaction is 150-200° C.; the pressure of the hydrothermal reaction is 2.0-3.0 MPa.

6. The preparation method according to claim 5, It is characterized in that The centrifugal speed is 5500-6500 r / min; the centrifugal time is 25-35 min; The ultrafiltration is membrane filtration; The pore size of the filter membrane is 0.40-0.50 μm; the concentration time is 10-14 hours; and the concentration temperature is 90-99° C.

7. Use of the carbon quantum dots according to claim 1 in the preparation of antibacterial products.

8. The use according to claim 7, It is characterized in that The inhibited bacteria are bacteria; the bacteria include Escherichia coli and Staphylococcus aureus.

9. Use of the carbon quantum dots prepared by the preparation method according to any one of claims 2 to 6 in the preparation of antibacterial products.

10. The use according to claim 9, It is characterized in that The inhibited bacteria are bacteria; the bacteria include Escherichia coli and Staphylococcus aureus.

Images